Developing 24 stitch optical illusion patterns for use on punchcard machines and more.

I have recently become obsessed with designs that fool the eye in any number of ways, and although knitting them in more than 2 colors is possible, I prefer the ease of only using 2.
Floats are likely to be too long in these knitting patterns for knitting them as single bed fair isle.
Software facilitates but is not necessary to develop repeats, the process may even be performed on graph pater with colored pencils if one so chooses.
Punchcard machine users are not always included in conversations, this post  addresses some ways of developing full 24 stitch designs and performing the necessary color separations for knitting them as DBJ where each color in each design row knits only once.
Brother KMs: punchcards and their use  reviews the basics including DIY development of simple motifs repeated in symmetrical tiled patterns.
The Manual for the Brother KR 830 offers this advice on DBJ knitting: Using lili buttons along with the slip stitch setting in both directions on the ribber carriage reduces motif elongation and keeps the aspect ratio of the planned designs closer to that in the originals than when choosing other DBJ techniques.
Ribber needle tapes are marked with lines followed by spaces. If the start under the first ribber needle on the left is on a blank space on the needle tape, simply end on the right with a needle over a line marking, or the reverse.
I am often asked why in my own illustrations the slide lever on the ribber carriage, a Brother “thing”, is always in the center position.
Reducing variables exponentially reduces errors.
If the lever position is not changed after those first rows or accidentally changed during knitting, the knit gauge will change. An example: working on final projects, more than one student in my knit studio design classes realized only after completing front and back or the second sleeve that the rib with the alternate lever setting not changed resulted in a visibly different rib height in the second piece.
Necessary adjustments can be made in yarn mast and respective carriage tensions, along with yarn choices appropriate for the technique.

ArahPaint and/with/or Gimp with a sprinkle of Mac Numbers have become my preferred go-tos for developing knit designs.
Designing can begin with simple drawings which do not require complex software knowledge and help to build confidence, using the electronic equivalent of graph paper and colored pencils.
Beginning with ArahPaint, with the goal of developing a 24 stitch pattern: load a new square picture, with an odd number of cells, in this case 13X13
Choose from the default palette, or set the number of colors to 3 and adjust the the results to include white, black, and one other clearly contrasting color Draw some starting lines/shapes that can be outlined with single pixels pencils Using the single pixel pencil tool, fill outlines in with color 3 To eliminate double pixels, mirror the image using the 25X13 pngrepeat mirroring using the 25X25 png Using the rectangle select tool, again to avoid double pixel lines, trim a row from the top and the right side of the design the 24X24 cropped result tiled as is with with the palette reduced to black and white The question remains as to how best to knit similar designs on any machine.
The floats are too long for FI, the repeat is best suited for DBJ.
The easiest color separation for DBJ is the one where each color in each design row knits twice.
To have each color in each design row knit only once, electronic machines offer the KRC button. The same result can be obtained in punchcard knitting by custom color separating the design.
When knitting DBJ with these separations, the 2 most common causes of stripes on both sides of the fabric are beginning the preselection row on the right, rather than the left, or as in my swatch, forgetting to push in both slip buttons.
This separation process for me is a very quick one using Gimp, I have not yet sorted a similar one in ArahPaint.
Using color to alpha as described in previous posts, the required files:
24X24 BW
24X48
24X48 color invert
24X4 with the top rows in a color picked from the program’s built in palette. Use Colors, white to alpha, to render the white see through. Copy the file to the clipboard, and use it to bucket fill with pattern  a new 24X49 (col inv png 48+1 blank row at top) bucket filled with the clipboard patternthe pink color to alpha, renders it see through, th last row is cropped, to 24X48, and is copied and pasted on the original 24X48 imageThe proof of concept swatchIf you enjoy designing with pencils in paint programs, the same approach can be used to produce a larger repeat, which makes the illusion more noticeable, ie in this 36X36 design.
Open a new window with an odd number of cells,  ie. 19. Copy and paste the upper left of the design on the new upper left corner, keep filling in linesRepeating the steps described previously, the 19X19 png is mirrored -1 in both directions, and trimmed to a final 36X36 design Modifications resulting in added shapes beginning to appear can be small in developing variations while continuing with the 24 stitch constraint.      Repeating the process, the files in sequence   The proof of concept was knit using the color white for the first preselection row to the right and as the first knit color row to the left, the color inverted version of the original repeat.  The KRC electronic separations are intended to begin with the white pixels in the designs, but the knitter can change that sequence based on their preferred placement of dark vs light colors.
Visualizing the reverse color placement in a knit swatch using Gimp  Mosaic and maze knitting, also known as floatless fair isle, has been discussed in many other posts.
The appropriate color separation shares much of the process with that for DBJ but the starting image is used as is, not rendered double length to start with.
The convention is the same as for fair isle, floats wider than 5 stitches are generally avoided.
In the 40 stitch design, there are spaces as wide as 15 cells with no contrasting color ones, which will be responsible for float formation.
Answering the “what if” question if the 24 stitch design design was used as a possible maze design.
The Gimp process in shorthand While the DDJ separation is used as is, this separation must be rendered double length in order for it to be executed single bed with the knit carriage set to slip in both directions, and color changes every 2 rows.
Using color invert on the final file, reduces the white cell, skip stitch float counts from a maximum of 15 to one of 6. Tiling will check on repeat alignments but has no relationship to the final look of the knit, where the slipped stitches will be gather the knit ones near them. The resulting swatch is highly textured, some of those extra long slipped stitches could be amended by making small changes in the design if it were to be developed further.  

For electronic models, the second 24 stitch repeat extended to 30X30
36X36  

ArahPaint in knit design 4 illustrates a way where following guidelines in Easily generate random weaves it is possible to quickly generate more random DIY designs for use in multiple techniques and stitch counts.

Figurative designs in mosaic knitting

Designs may be developed to incorporate lines and grids by outlining motifs, filling in the results with grids or lines, and even color inverting the results.
From an early 2013 post:
Each number on the grids below represents 2 consecutive rows of knitting. The design may be elongated in the drawing of the final repeat itself prior to punching holes, marking mylar or pixels, or elongated using the built-in setting in the KM used, whether electronic or punchcard.
Color changes are required every 2 rows.
The grids: After a motif has been separated, usually color 1 is represented in row 1, and all odd-numbered rows
color 2 is represented by row 2 and all even-numbered rows
long horizontal lines in mazes usually occur on odd-numbered rows
even-numbered rows typically have no more than 2 black squares marked side by side
on odd-numbered rows, the white cells slip
on even-numbered rows, the black cells slip
odd-numbered rows are knitted in the primary color (black cells)
even rows are knitted in the contrasting color (white squares)
Forming shapes and or text on the vertically symmetrical grid: 
2023
These single-bed knits are ideal when float control is an issue, or when one wishes to reduce the bulk of fair isle techniques. There are, however,  geometric design restrictions and the resulting patterns may be too “busy” for some.
Separated designs interrupted by black or white lines rather than single-cell dots are knit using slip stitch on the single bed, or in every needle rib with the knit carriage set to slip or even tuck in both directions on the top bed, and the ribber set to knit in both directions, a very different fabric.
The basic procedures for drawing figurative repeats may be worked out using graph paper or image processing programs, depending on what tools are available.
Working in Gimp, generate a file in a basic grid, which in turn may be tiled to any dimensions needed. Using the bottom grid is problematic in creating figurative mosaics using the connect-the-dots technique. Attempted vertical lines do not connect cleanly.   Cautious planning is required in executing figurative designs.
Clean-up will often result in solid color surrounding shapes or the addition of some short solid lines.
Doodling with blocks on both grids in a spreadsheet.  Text becomes more complicated if one seeks to emulate favorite fonts or to work on a small scale.
A spreadsheet using multiple colors may make the drawing easier to start with. By necessity, repeats will once more need to be large.
With practice, one develops favorite ways of reaching the chosen goal. Large shapes may be superimposed on either dotted grid for final editing depending on what sort of border one wishes to add in designs for end-use in large pieces such as blankets.   Figurative drawing occurs on rows marked with black pixels on the grid where black dots line up vertically.
White rows remain blank except where the black dots in the shape’s outline need to connect vertically.
After the outline for the motif is created, the filling-in of the shape is executed connecting dots once again.
By necessity, these shapes need to be large.
My first design is 68 stitches wide by 40 high. Processing the image is done on the same design. When color-separating Mosaics the design is not elongated.
Using the steps described in previous posts on a copy of the initial file: color invert, It is interesting to observe that the knitted result matches this image.
The file may begin as black and white indexed, but prior to adding colors the mode needs to be changed to RGB.
Add a third color beginning on every other row beginning on row 1,    using layer, transparency, and color to alpha, the third is removed, leaving black and white.  The alpha file is copied and pasted on the original resulting in a knittable mosaic repeat that requires elongation X2.
Check that the file is in indexed BW mode prior to saving it for knitting, it will need to be elongated X2 if used as is.  The above doubled in height, now 68 stitches wide by 140 high, may be knit as is.  Those solid black areas are OK. On the corresponding design rows, needle selections on nearly every needle will take place, those needles will knit the color in use at the time.
The tuck setting is possible, the final appearance will be quite different. For my swatch, I used the slip setting.
Slip-stitch pieces tend to have vertically straight side edges, while tuck ones tend to have wavy ones.
The floats on the purl side are still only 2 stitches wide.
The all-knit areas are not reduced in height, so they ripple initially and became flattened with blocking in this case, but caused the top and bottom of the horizontally striped segment to curve.
Starting knitting using the light color as opposed to dark will color invert the design.
The blue yarn used here is wool and the yellow is acrylic.
The swatch was steamed and pressed.
The dark color is dominant.  Visualizing the color inverted image using the photograph of the swatch rather than actually knitting it:  A 48X46 heart to play with for DIY Beginning in a spreadsheet followed by transitioning to Gimp can use a similar dot-to-dot design concept. It offers the opportunity to make adjustments before fixing on placement for the final black pixels over other colors. Moving away from dot to dot to “visually pleasant” does not necessarily work.
The flower design chosen and committed to for the moment is 37X32, visualized on possible backgrounds, and placed on a final one drawn with straight diagonal lines in pattern, for the test knitting  Aside from whether accurate tiling is possible for that final repeat, it has far too many white rows uninterrupted by black squares. As in any slip-stitch fabric, a stitch is held in every white cell or unpunched area location until a black cell or punched hole follows it, the result is very elongated single stitches on the knit side: There is a limit as to how big a part of any final mosaic repeat can truly be freeform.
It helps to develop a library of personal grid variations, to be willing to observe some basic rules, and to have an affinity for the overall look of the results.
In terms of the basic grids, the horizontal stripes have already been shown in the fish to produce 2-row all-knit stripes in alternating colors where they are placed in the design.
The vertical stripes create this result when proofed, and it can be recognized in the png for the body of the fish  Developing a DIY background: I find it easier to work on such designs on a large table in Numbers, which allows for placing a variety of colors and in the same document more easily, and then converting the outcome to a BW indexed png in Gimp. The smallest isolated repeat, in this case, is a square, 20X20 Make certain it tiles correctly before proceeding:
The final file doubled in length shows no areas where extended slip stitch rows might be an issue. This step is not necessary as one begins to trust the process. Returning to that flower, on the white-to-alpha ground, a 37X32 saved file, open it in Gimp.
Open a second file, using the background-repeat, and tile it X2 in both height and width to a matching 40X40 size.
Copy and paste the flower onto it in what appears to be a visually pleasing location, clean up the surrounds, and save the png.  Proceed with the now familiar steps: The final repeat must be elongated X2, color inverting may provide a better sense of what cells knit or slip, and it may be used to knit the design.     The working 40X80 repeat: Once again, the completed swatch visually matches the original file, color inverted.
The latter provides a sense for guessing if the knit results are pleasing and it offers a way to explore different colorways or matching yarn colors.
Pursuing the dot-by-dot concept can lead to endless DIY designs. Playing with motif scale in Numbers: Isolating part of the design in Gimp: 42X44  A variation using multiples on an 80X80 canvas.  Loving that DIY background? To create a frame
1. choose a finished canvas size, ie 120X120, and fill it by tiling the DIY background
2. open a second file to, in this case, 80X80, in any color including white. I chose yellow as a way to place black border lines more easily
3. copy and paste the second file onto the first
4. add a solid color border at the inner and outer edges of the frame, outlining the shape at its center.  At this point, any image also 80X80 may be simply opened in Gimp, copied, and pasted over the yellow. Files to play with: the frame with a transparent center to be pasted in place on other graphic files,  Here with a dot-to-dot center to draw on, and the file with central flower motifs to use or edit further.  The final choice then needs to be made as to how to use the final image.
One option is to separate the motif for use as a single bed 2 color slip stitch, and the second is to simply use the built-in KRC color separation in electronic machines to knit it as DBJ.
Motif definition requires large-scale designs limited by patience and imagination.
Autofill, command key and other shortcuts can help execute them more easily and quickly in spreadsheets as a first step.
This start of a hummingbird, inspired by a small segment of a Pinterest find, is already 54X101 pixels, ending my exploration of these knits for the moment.  

When editing or developing large images a series of guides may be useful. To configure them, see pos:t Gimp update for Mac 2

Color separations for larger scale mosaics and mazes

There are generators online for many generators to aid with knitting design. In 2015 I published a post on working with generated mazes: Gimp charting 1
The mosaic and maze graphics before their color separations are not suitable for fantasy fair isle double bed knitting. There are too many vertical white pixel rows begging for carriage jams no matter the machine used. The same long lines of black or white cells make them unsuitable for traditional fair isle knitting.
Visual clues are helpful as steps get navigated.
There are many ways to achieve the same goals. In converting small-scale repeats, one option is to begin with a file previously used and separated, magnified to 1800X.
1. using the rectangle select tool, begin on row 1, extending the handle outside the image, I work from left to right
2. hold down the shift key, and continue selecting every other row. As each row is selected, it is outlined with dots. The handles to the right and left of that row serve as guides as to the last row worked, moving up as separation progresses. Clicking on the rectangle select tool at any point fixes the layer, and the dotted lines will disappear. The process could be performed in steps, with guides placed before color inverting the previous steps in the sequence and moving on to the next. The guides remain until they are removed by clicking on the check mark beside show guides, or with the Image / GuidesRemove all Guides command.
This method may be more error-prone than using layers or colors to alpha to render rows transparent when developing large designs.
3. after each pertinent row has been selected, choose the color invert option, and save the resulting file. The first step is completed in the separation.
The file then must be color-inverted and lengthened X2 before knitting. The result matches the separation in the previous post.   Holding down the shift key when using the pencil tool on any image produces very different results.  My samples continue to be knit on the 930 using img2track, a download program I find reliable and easy to use. The only errors in programming I have encountered were due to operator errors, not software ones.

Since 2015 working with larger images has become far less daunting as my methods for color separations of mazes and mosaics have evolved.
Laura Kroegler’s online Mosaic Pattern Generator is still available. Returning to it, and using these parameters the pngs were downloaded both in red and then again in black and white. A 38X38 stitch repeat was isolated, and using Layer/Transparency/Color to Alpha a knittable mosaic design was obtained which, when knit, would require elongation X2 for color changing every 2 rows The last file, doubled in length to 76 rows in height, requires no further processing The separations are achieved now in just minutes.
The proof of concept swatch: when using repeats that are so much wider, one must commit to far larger swatches to test them. In addition, the placement in the final piece may matter with shifting the pattern to highlight a preferred center, here the machine was allowed to place the design as a simple overall one on 78 stitches by 116 rows. There are droves of inspiring large-scale mosaic crochet images published nowadays, which led me to wonder about DIY similar large graphic mosaics in machine knitting.
I performed the first color separation with shortcuts, mirroring the cleaned-up repeat, did not verify each step with tiling, and committed to knitting a test swatch. A 68X136 repeat X2 in width and at least 40 more rows in height, produced a 16X24 inch test swatch, wherein a couple of missing pixels became noticeable.
The swatch was also knit using slip in both directions on the main bed, which produces a narrow, short fabric as opposed to wide and short when using the tuck setting. Back to the drawing board.
The initial approach is similar to that used in creating mock filet crochet shapes on the machine.
With present tools the results process is easy and quick: to begin with, choose any symmetrical design where the shaping of the motif occurs in single rows, this one measures 23X23  scale the file X3 in both directions to 69X69 save this brush to use later for bucket-fill in the design.     Choose fuzzy select by color/black, each shape will be surrounded by a dotted line bucket fill the selections with the saved pattern click on rectangle select to fix the layer, work on and clean up the repeat, and check a magnified version for any missing or misplaced pixels.  Save the png. for reference before continuing to work. Make one of 2 choices. If the goal is to place a motif and to add borders or horizontal additional design stripes, create a new canvas, larger than the above, fill it with the same pattern, and then Colors/Invert.  Click on the rectangle tool to fix the layer.    Change the white color to alpha in the previously processed snowflake, click on the rectangle tool again copy and paste the file onto the color-reversed grid, and click on the rectangle tool.  Check the pasted image visually, and continue adding any other designs.  If the goal is to produce an all-over design, crop the shape on the dotted ground, and save it as a 69X69 repeat. Pasting the original on an equal-sized color reversed dotted ground does not work.  Tiling the result of the cropped repeat will show the need for cropping it by one row at the top and one column to the right.   The resulting repeat, 68X68 tiled X3 in each direction for a visual check.  Using the process previously described
1. open the 68-stitch file in Gimp, and magnify it to at least 800X for a visible grid
2. open file/new, equal size and magnification
3. copy and paste 1 on 2, click on the rectangle select tool
Colors/invert, click again on the rectangle tool or anywhere in the work window 4: magnify further if needed. Using the pencil tool fill in every other row beginning with row 2 in a contrasting palette color, and click on the rectangle tool 5. Layer, transparency, color to alpha, as described in the last post, click on rectangle tool 6. Copy and paste this result onto the 68-stitch file in the first window, there will be lots of dotted lines onscreen  Click on the rectangle select tool to paste the image in place. Since those large areas of white will be knitted in a tuck or slip fabric, the above result needs to be color inverted. If used as is, set the machine’s built-in double-length function.  Doubling the length of the file before the download to km Added info on the technique may be found in the post on More separations for various knits using Gimp, color to alpha
This sequence presents the method of working in a different way than above, and sequential files are provided to test in DIY experiments begin with the 68X68 image color invert it open a new file, 2 rows high with an added color, and save it to the clipboard, white color to alpha use the brush to fill the color inverted image,  red color to alpha and paste the resulting image on the original double the file in length for knitting as mosaic, results matching the previous experiment  Part of the view on the img2track screen for the 68X136 file is ready for download. Committing to proving the concept:  Using the same approach of tripling the original, the repeat was used to render a larger-scale mosaic. The process becomes fiddly because using the fuzzy select tool and the bucket-fill-in pattern does not work cleanly on areas only 3 pixels wide.
That said, it is possible obstinately, in stages, to get from this, 36X54 To a 36 by 56 mosaic
A last edit Perhaps falling in the category of “don’t have to simply because I can”.

Images at this stage of the process may be knit double-bed as a “fantasy fair isle” with no further separation.
On an electronic machine, download the repeat, program it for the number of needles in use on the top bed, and select the KRC separation button.
The first preselection row will need to be from left to right.
The main bed is set to tuck in both directions, the ribber to N in both directions.
There will be lots of non-selected needles tucking on rows with large numbers of side-by-side white cells. Because the fabric is being knit using every needle on both beds, each main bed tuck loop will have a knit stitch on the opposite bed anchoring it down. Those rows will appear more compressed, producing narrower horizontal lines The yarns used were very thin single strands of  2/28 at tension 4/3. The result is a very lightweight and loose knit with lots of drape. The 72 stitches by 140 rows swatch measured 16 inches in width by 10 rows in height. Perhaps a good method for summer shawls, worth exploring in thicker yarns for blankets. A closer look at the structure:  A larger BW design was processed using no modification of the original 75X71 motif. When using Gimp/File/Save, the result is a .xcf document similar to PSD files in Photoshop. It will store layers, transparency settings, and more information associated with and parts of the same project. Note to self: before deleting the .xcf make certain that at least the final png has been saved.

If one is familiar with image processing and fond of the maze appearance in designs, there is a font to try: Mazeletter
The downloadable associated documentation and source for inspiration: http://mazeletter.xyz/Mazeletter.pdf.
A sample text: in a 129X32 BW version with no pixel clean-up  Mosaic4way, is potentially usable for single bed fair isle or dbj.  The BW file, 199X32
There are variable loss of detail or added random pixels when scaling designs containing more than 2 colors. ArahPaint’s guess weave from grid tool is the best I have found for scaling such samples to knittable sizes.

Gimp Update for Mac 3_more on color separations

The latest version Gimp Download site
I am self-taught. As I learn new tools, my workarounds may be convoluted and more complicated than they need to be and evolve with time. I do not delete older posts or their content, but do occasionally add links to later posts or dated notes.
I began designing and charting in the days of having to draw on graph paper and cutting up results to see if the repeats would tile properly when knit, or to place them for alignment variations such as half drop or brick.
Scanning amounted to tracing with a marker onto blank sheets of acetate or tracing paper.
The availability of commercial acetates for purchase at seminars, printed in pairs of matching horizontally striped sheets in lines separated in a variety of widths, offered an advance in scaling designs to a knit aspect ratio. Copy machines became useful friends.
DBJ designs in the punchcard studio, when I began teaching, were accomplished at first with the use of cards themselves as templates and overlays, involving a series of time-consuming methods for each type of separation ie.  So many such processes are now nearly instantaneous by comparison.
Earlier this year the post Using Layers in Gimp for color separations explored several fabrics beginning with B/W motifs.
Sometimes lightbulbs go off leading to other ideas for achieving results in quicker or easier ways.
This color separation method for mosaics continues to use Layers but in a different approach.
A spreadsheet may still be used if preferred to draw the initial draft of the design, working in black and white only would be fine, and the import could then be processed in Gimp.
Mosaics and Mazes are generally knit with color changes every 2 rows using either the slip stitch or tuck carriage setting in both directions. Beginning with any DIY or published design, to knit the motif using the tuck setting, there are basic rules to remember.
This illustrates possibilities using a random 6-stitch repeat, A.
If the plan is to set the knit carriage to tuck in both directions, the design would need to be color-reversed to BThe white cells in B represent loops held on corresponding knitting machine needles, the limit in Japanese standard machines is often 4. Black cells represent knit stitches, generally seen in groups or on either side of tuck stitches/ white cells, to anchor the loops down for proper stitch formation. There are some infrequent exceptions to that rule.
When uncertain as to results in developing DIY designs, begin with a published repeat to build up confidence. This is a hand-knitting resource for endless inspiration, no separations are provided in the book text.  There are always many ways to achieve the same task depending on the specific program used, one’s level of skill, and individual thought process.
This method uses multiple windows in progression.
When starting out, save the result in each step for added practice or in case any step is accidentally deleted.
This is by Kathleen Kinder, published in Floatless Fair Isle, p. 87 Though the final designs are saved as black and white pngs or bmps, to work using colors in separations, the mode needs to be set to RGB. For very small repeats, use view, show grid,
magnify 1800X, type in a number for a preferred value,  or use the command key in Mac and the scroll wheel of your mouse to do so. Using the pencil tool draw the repeat in black and white Selecting file, new, open a canvas in the same size and magnification, with each step a new icon appears at the top left of the Gimp window to select any file, simply click on the corresponding icon, use Edit Copy or command C, and then edit, paste or command V to place files onto new selections.
Copy and paste the first image onto the blank canvas and colors-invert the result  To draw straight lines on a Mac, use the pencil tool to place the starting pixel. Hold and drag the mouse to the desired endpoint. As this is done, a guiding line will appear. When the endpoint is reached and the mouse is released, that line disappears and the selected area will fill with the chosen color.
When using the 2-pixel brush, the mouse must be placed slightly into the second row of cells before dragging it for the line to remain straight and in the proper rows. If an error is made, choose Edit, Undo, to eliminate any step.  Continue to work on the color inverted file, and beginning with row 1 fill in every other row with a distinctly different color. To fix any layer before continuing, click on the rectangle select tool, and then again anywhere in the work window.
Getting rid of the red: this will be the immediate appearance of the image in the window, disregard it.
Right-click on Color/white, choose the foreground or background color or left-click on the Color bar, and click again to choose the color from the palette window. Choose rectangle-select cool, click on the result to fix the image, and the color window will disappear. The result: Copy and paste the file onto the initial image, there will be dotted lines upon the placement,  Click on the rectangle tool again, and then in the work window for the final png repeat. Change the image Mode to Indexed BW if its end use is a download to an electronic machine  Why is it different than the Kinder repeat? It is easier in drawing to color in white squares as opposed to black, so the repeat in the pub is the above, color reversed.  Punchcard machine users may mark the black squares and then punch all others.
The last step: if colors are to be changed every 2 rows, remember to use double length or to program/punch the last png double length.  An illustration for the full double-length punchcard repeat. The above, 12X36 repeat was color reversed and tiled twice to meet the 24-stitch width requirement. The 36-row height also meets the minimum height requirement for punchcards to roll in continuous patterning.
Mark the black cells in the image below on the card, and punch all the white ones. These fabrics are often more interesting using the tuck setting than the slip stitch one.
I have a lifetime supply of copper yarns from my jewelry-making days. This repeat is more a maze than a mosaic. Using a fishing line or wire can sometimes also produce interesting effects.
The blue yarn is composed of 3 strands of 2/48 cashmere/ wool.
The wire is a 32 gauge coated copper magnet wire which tends to flatten the final knit. On the machine, it is hard to recognize repeats due to the very short floats, and the unusual fiber rows can appear to be see-through Using a light color wool rayon as the second color. Using a separated 16X16 repeat from the 2020 post to knit a swatch for Instagram, I noticed a solid 3X3 block in the center of one of the shapes. Because the wire is see-through to some extent, the white stitch floats behind the blocks are noticeable. The copper wire used was 40 gauge, 3 plied. The higher the gauge number the thinner the wire strands, nearly invisible when threaded and while being used. Because the knit tension was as tight as possible, the stitch definition is lost in a few spots.
The original design motif, on the left, was missing a white cell in the location of the red cell. It was quickly converted using only Gimp.  Comparing the old repeat to the new, that problem pixel may easily be located. The corrected file before lengthening X2,  double length  Proofing a pattern is best done using comparable weight, familiar yarns. Here thin poly and 4-pound fishing line are used as the second color It takes a bit of squinting to see the match.  Testing the same repeat in more “friendly” and equal-thickness yarns This 24X28 repeat from the earlier post is reworked in this method repeating the process described here, it took longer to render the repeat than to perform the color separation.  The tiled alignment check
The steps are in sequence and produce a result matching that achieved in the previous post. A reminder: step #6 result would need to be doubled in height, whether by altering the file prior to download or by using the built-in functions in the machine after the download. The theoretical color separation to knit the mosaic as DBJ where each color knits twice, the repeat single length, 24X56 double length, 24X112

Double jacquard using punchcard machines shared manual methods for including one avoiding the elongation by matching the electronic built-in KRC color separation. Using Layers in Gimp for color separations introduced an approach using only Gimp.
There are times that the 2-color separation for DBJ which knits each color in each design row twice is necessary for the intended knit technique.
When testing new methods, one may begin with files that have already been proofed. This file is created so no elongation is required, beginning with the shape elongated X4.
From the layers post, the double-length separation where each color in each design row knits twice Duplicating the result using layer/ transparency  Longer repeats can become more complicated to separate. Testing the results by necessity requires larger swatches.
Using Stitchworld #548, a 24X40 repeat, as with mosaics1: draw the desired repeat in Gimp
2: when the drawing is completed, tile the repeat to check alignment, save the image if desired, or discard it
3: in the original window, scale the image to double its original height, now 24X80
4: using file, new, open an image on a white ground in the same size and magnification, a minimum of 800X, with grid view, as the first window
color invert
continuing on the same image, changing magnification as needed for ease of visibility ie 1800 X, choose a palette color, and using the pencil tool fill in every other row beginning with design row 1 using it
5. using color to alpha will remove the blue color in this case, and the image will change in appearance, the blue is now transparent. Copy the result.
6: use the second image, and paste it directly onto the one in the first work window.
For the repeat to knit successfully as DBJ, the resulting  24X80 file will need to be lengthened X2 to 160 rows in height for accurate patterning to occur. The design lengthened X4, using a 2-pixel pencil beginning on rows 3 and 4,
produces a 24X160 file that requires no elongation.  In this DBJ version, the first preselection row is made toward the color changer, followed by color changes every 2 rows.
My proof of concept is knit with the knit carriage set to slip/slip and the ribber setting left to N/N, creating long stitches.
The height of the design, any bleed-through, elongation, drape, and stretch, are variables influenced by carriage setting changes on either or both knit and ribber carriages.
By default, DBJ knitting requires many more carriage passes than 2 color patterns knit single bed as fair isle.
My swatch does not begin at design row 1 because I forgot to set the knit carriage to slip after the first preselection row and color changing on the left.  Scaling the knit for a sense of the degree of elongation The above separation is the default one in Passap knitting machines.
Japanese electronic knitting machines perform the separation where each color in each design row knits only once automatically by engaging the KRC function.
Punchcard users can achieve the same results for repeats that meet the width constraints using a maximum of 24 stitches or factors of 24 in width.
The separation where each color only knits once from the layers post began with the result where each color in each design row knits twice: My first effort using layer transparency to separate for each design row color knitting only once begins with the double length separation opened in Gimp, not necessary as seen in notes that follow.
Using the pencil tools, marking begins on the second and then even numbered design rows.
When # 5 is color reversed, it matches the separation using layers in the above far right  Using the same concept, the first test began with the separation already completed for the repeat that would knit each color in each row twice.
Toggling magnification helps to make the height of the repeat manageable. Errors are easy to spot and correct if noticed early, a few rows of pencil marks can simply be undone. Save the final png, also 24X160. The separated design is suitable for punchcard machines, my swatch is knit on a 930. Since these separated designs are programmed as fair isle designs, there will not be any color change prompts provided by some machine models.
The first preselection row, as when using the KRC function, is made from left to right. The knit carriage is set to slip both ways. The ribber carriage is also set to slip both ways on an even number of needles, and lili buttons are in use. The visual difference in scale between the two different techniques and color separations.  The simplified method begins with the original design scaled X2 to 24X80. The 2-pixel pencil tool is used to mark the resulting design beginning on rows 2 and 3, skipping the next 2 rows, and repeating the process
Committing to a larger test swatch: The repeat though successful in this case is different from half the first one obtained the long way, the concept merits testing with other motifs.   Years ago I shared the way punchcard knitters may create a DBJ card using a series of templates. The starting 8X8 design was often used in my 2 color DBJ posts. On the right, it is repeated across 24 cells, as it would be in a punch card.  Using layer/Transparency/Alpha the same results can as when using the card templates may be attained in just minutes. Here each color in each row would be knit only once:  In this case, the final result would need to be elongated X2 in order to knit each color in each design row twice. This separation requires no elongation. If the plan is to print a template to aid in marking a card prior to punching, one way to determine the required template size is to measure a punchcard with a ruler in mm.
The width of the card is fixed to a print width of 108 mm since the card will always be 24 cells wide. No calculation is required.
In height, the 60 rows on the factory blank card measure 300mm, 5mm for each cell.
I cropped the chosen image to the top 39 rows and scaled it to 108X195 mm.
(39X5).
When printing on US letter size, with no adjustments other than to the image, the limit appears to be no more than 45 rows per page. I was not able to print directly from Gimp.
The file, exported, opened in Preview, and then printed, is shown with a card superimposed on the printout over a makeshift light box, ready for easy punchcard marking even though the printed cells were not all of the same ink density.   2024 the subject of elongation in DBJ designs recently made the rounds in forum again. I was not quite sure where to share this, settled on here
Vertical striper backing on Brother machines is rendered possible by manipulating ribber needles in conjunction with the use of lili buttons.
This swatch uses the same 40X44 pixels design The tension and yarn selection choices remained fixed.
1: conventional striper backing, with the ribber set to knit in both directions
2: half striper backing, with the ribber set to knit from left to right and to slip from right to left. In this technique as the carriages move from right to left, floats will be formed on the top bed. As larger number of needles are knit on either bed, the tension should be adjusted accordingly, here it was not, resulting in those dropped stitches. The floats peek through behind the resulting hole.
3: the traditional birdseye backing, resulting in the narrowest portion of the swatch.

 

 

 

ArahPaint and Gimp in knit design 3

Previously published:
ArahPaint and Gimp in knit design 2
ArahPaint meets Gimp in knit design 1

Subsequent posts on using Gimp Layers to process images:
Using Layers in Gimp for color separations
Layer/Transparency/Color to Alpha Gimp Update for Mac 3_more on color separations

Gimp allows one to work on multiple images with only a single window open, left mouse clicking on any one of the images will bring it into view for editing. In the dark theme, it is hard to see the difference, but a lighter border actually surrounds the active image distinguishing it from the others, outlined here in yellow In Arah, multiple windows may be opened at any one time, and left-clicking on any one of them will bring it to the front for editing.   When working using the same file in more than one window, the degree of magnification needs to match in each.
Spreadsheets and paint programs may be used to achieve color separations for designs intended for specialty fabrics, many worked on the double bed.
Two places to begin exploring them here are for knitting single-bed mosaics and double-bed jacquard in its form where each color in each design row knits twice.
It is unlikely to happen often in knitting that more than 6 colors are used in any one fabric except perhaps in an elaborate color-changing fair isle.
The palette that appears in Arah when opening a new file is random, as seen here when two new files of the same size are loaded  If one’s preference is to reduce the number of colors, the specific number may be set by choosing from the colors menu, editing the number identified as that for the working palette, changing it to the new value, in this case, 6, and the palette reduction occurs as seen in A. For most knit repeats a black color is handy, any one of the 6 colors or more may be adjusted as described in the previous post, seen in B, where black has been added, replacing the color in position 1. More Gimp information: https://docs.gimp.org/2.10/en/gimp-palette-dialog.html
Some of the related content in brief: the former versions of GIMP had a “Save palette” command. Palettes were stored in a specific folder via the preferences pane. Easy to do and manage. It no longer exists.
To save the palette of an image, indexed or not, you must now import it from the image.
The “Palettes” dialog is dockable: from the Image menu, select Window, Dockable Dialogues, Palettes.
A few dozen more or less randomly chosen palettes are supplied with GIMP.“Import Palette” allows you to create a new palette from the colors in a gradient, image, or palette file.
Right-click in the space to the right of the illustrated palettes to call up the import option, or for palette editing. It is not necessary to index the image, this image was used in RGB mode. A palette name can be assigned, and if previously used, a number will be appended by the program.
The number of colors: the default is 256, you can set the number to any you choose. Gimp will try to create a palette by spacing the number of colors evenly across the range of the gradient or image. Each screengrab in the top row shows the initial selections for gradient or image, and the second row of screengrabs notes other changes made when choices were available and the results. White dots mark selections as seen while using the program.   Using the same image, indexed to 5 colors, the custom palette is rendered in a one-step process. The gradient seen in the first position on the top left was randomly assigned by the program and does not influence the results. The Columns selection number settings only influence the way the palette is displayed and have no effect on the way the palette is used. The lower the number, the larger the display size of each color unit.
Double-clicking on any palette color will magnify the palette view on the theme color background. Left-clicking on any color makes it available for drawing, the selection will have a dotted bounding line and the selected color will be assigned to the foreground position,  Right-clicking on a color results in these options.  The imported palette will be added to the Palettes dialog and is automatically saved in your personal palettes folder when you quit GIMP so that it will be available in future sessions.
In Arah, the color palette will always display the colors of the active layer. The working image contains colors intended for use in my designs.  In addition, please see the note from the developer in the comment at the end of the post.  The palette tools: A: if you press this icon the program will underline the colors actually used in the image, since all colors are used in this case, each color is underlined in either white or black in this instance  D: adds color(s) to the palette  B: removes unused colors in the above palette, it would restore the original colors
C: removes duplicate colors, not applicable in this instance
E: removes the last unused color, will not work if all colors are used.
Changing color positions in the palette: to switch the position of two colors in the palette, click the chosen color in the palette, move the cursor to the color you want to switch the position with, and press the left mouse button while holding the Ctrl key on the keyboard. In this instance, the color was duplicated in the new position.  Knitters designing for dbj are likely to work with a limited range of colors, often 3 or 4 max, in specific palette ranges to ready images for download.
If color separations for 3 or more colors are done in shades of grey in terms of technical details, you need a pattern image that is 8-bit greyscale, with each color in a range of 8-bit values. So for 4 colors, it would be 0-63 color 1; 64-127 color 2; 128-195 color 3; 196-255 color 4.
Binary images have only 2 possible intensity values, normally displayed as black and white with values of either 1 or 255 for white, and often 0 for black.
That convention may have led to the selection of white as color 1 in automatic separations such as the KRC Japanese one, where white is selected first. In a greyscale or color image, a pixel can take on any value between 0 and 255. Designing for fair isle, or when attempting to visualize and illustrate slip and tuck fabrics with frequent color changes, more colors may be required even though the final download will be in black and white. There is a quick way to add random colors assigned by the program and based on the initial palette: The magic wand tool allows you to work on consistently colored areas without having to select and outline each.
To alter a single color using the bucket tool, click on the wand, then on the color single color area you wish to change, it will become outlined by bounding lines.
Click on one of the colors in the expanded palette, and it will automatically appear in the foreground color position, and it may then be used to bucket fill the chosen area. Flatten the image using the merge-down tool.
If the foreground color, in this case, white/0, needs to be changed, in order 
to choose all pixels in the foreground color, click on the wand, and use Tools > Select by color or Shift+W. This function works only on 8-bit pixel images. Click on the color you wish to use to replace the ground, and bucket fill with the newly selected color. Flatten the image using the merge-down tool.
Changing multiple color blocks in the same color could be selected by the tool, but filling each of them one at a time was required.  In Gimp a similar tool is the fuzzy select, which also allows for changing the color in a selected area or for selecting and changing all pixels in that color. Selected areas will also be outlined in dashed bounding lines. Bucket fill may then be used to replace color(s). The option is offered to choose either foreground or background for the fill.  2023 in Gimp 2.10.34 use and hold the shift key prior to selecting and using the bucket fill tool to change all the areas outlined by dashed lines. The bucket-fill tool itself now works again on any area with a defined boundary, no other, following action is necessary.

Click on the rectangle select tool and then on any spot in the work area or on the image to set the image. The dashed lines will disappear.
In terms of saving the palette in Arah for future use, I saw no specific directions in the manual.
The color palette displayed is always the one used in the active layer. As a workaround: open the image, and the associated palette will be displayed. The repeat begins drawn 24 pixels in width, by 24 in height.
Select clear from the edit menu, or bucket fill area with white
If the size of your intended drawing area is different, choose the option Resize Image from the Image menu. With the chain link intact, the new canvases are created keeping the aspect ratio. Enter a new value for width/height, hit return, or move the cursor to the alternate value, and its number will automatically change to a matching one. Click OK to use the new canvas, or reset if you wish to return to the original 24 by 24 pixel one for a different edit.
With a broken chain link as one of the two values is altered, a preview is available. If both values are to be changed, break the chain link, enter the two values in turn, and a preview appears for each step. Ok is used again prior to saving, or choose reset to return to the previously used setting. Color separations can make specialty fabrics possible to knit which are outside the possibility of doing so simply by changing cam settings. Two instances are mosaics and DBJ where each color in each design row knits twice. Separating each may be done in two ways. The first method, convenient for longer repeats, requires that the result be elongated X 2, whether in the repeat design software or after download to the machine or using the elongation X2 function in the punchcard models. For illustration purposes here I will be working to create files that do not require elongation.
Mosaics and Mazes are constructed in similar ways and are sometimes referred to as floatless fair-isle even though technically speaking usually 2 stitch floats do appear on the purl side in the alternate color used with each color change.
Many such repeats may be knit using both the slip and tuck settings, the latter is the more interesting of the two on the purl side.
When learning structures it may be worth beginning with a published design.
Kathleen Kinder decades ago published two books, one with 24 stitch repeats, the other with 40 stitch repeats, with the separations included as well This, by Barbra Walker and intended for hand knitting, offers a huge library of designs for inspiration and conversion Following specific rules it is also possible to develop DIY repeats from scratch. That said, the repeat used in this blog post happens to have a known value of 12 pixels by 12Magnification in Gimp is achieved by selecting or typing in new percentages at the bottom of the window.
Entering and exiting the full screen may be controlled via the view menu To exit, it right-click at the very top of the window to expose menu options and select deselect full screen.  In Arah, if you press any number from 0-9 on the keyboard, you will change the zoom directly to that level (1 means 100%, 6 means 600%, 0 means 1000%). The plus + and minus keys- as well as the magnifying lens icons, will zoom in and out To use the entire space available in the window, choose Fit to Window from the view menu or select Ctrl+zero.
If working in more than one window this option makes repeats the most visible, scaling back can be done by counting the number of selections, helping to match the new picture magnification to the first.
Press the escape key on the keyboard to return to the original 100% view.
To work using the full screen, select the option from the view menu. To exit, right-click at the very top of the window to expose menu options, and select exit full screen Separating the design: ultimately the planned final graphic repeat would be a BW png used for electronic download, programmed as a fair isle one, but knit using tuck or slip settings, it may be drawn initially using only in those 2 colors. Black may need to be added to the palette selections.
One may always draw on a large canvas and then crop as needed, but as a starting point, it may be easier to simply match canvas size to the published repeat being used.
It is handy to have an extra column to help track image processing during the separation, the repeat above is identified as being composed of 12X12 pixels, one could begin with a 13X12 canvas.
A second way to provide the 13th column is to work using 2 windows, matching magnification,  and the second with a different, larger pixel measurement than the first. Copy the contents of the original work area and paste them into the larger canvas in the other window. Crop to new size if necessary.
To illustrate the two-window process, here the original BW repeat has already been drawn and elongated X2
A. Use the rectangle-select tool to capture the whole image in the first window, bounding lines in the colors of the palette in use will outline the selected area
B. Use the edit menu or command C to copy the selection, edit paste, or command V in the new window to place it.
When pasting on a different size ground, the bounding lines will also appear in the new image, the contents remain moveable,
C. Place the selection where desired on the new canvas,  when satisfied use the X, merge down tool to flatten it.
The quicker method begins with a canvas one pixel wider than the repeat, 13X12.
Adjust magnification, for comfortable viewing in the editing process.
View: show grid 2
Colors: set the number of colors to 6, and adjust the #1 color to black, white is in position 0 in the palette by default
Activate the pencil tool, and draw a vertical line on the far right in an easy-to-see color choice other than white or black
Using black, fill in pixels for your first draft of the pattern repeat
Image multiply YX2, resulting in 13X24
Using the pencil tool fill in the first 2 design rows followed by every other pair with white. Magnify image A to a comfortable work viewing size.
B and C: using the rectangle select tool, with the left mouse button, place the pointer on the purple pixel, drag the mouse across each pair of marked rows, release the mouse, and use Command I to color invert, and merge down to eliminate the bounding box.
The purple pixels will change color as well, making it easier to track what rows have been altered already.
D: crop the image, removing the row with colored cells for the final repeat
If for some reason you are processing an image that is color reversed, the steps are identical, but tuck or slip stitch fabrics, black pixels or punched holes knit, white pixels or unpunched squares tuck or slip. For this reason, the cropped final result would need to be color inverted prior to knitting or punching holes. This separation for 2-color DBJ results in its potential use in many fabrics other than DBJ and may be performed by some programs used to download multiple color patterns to the machines prior to knitting the fabric. One such fabric is drop-stitch lace.
Punchcard machine users would need to separate the colors manually, or if Dak is available, the separation may be done using the program and a corresponding template may be printed as a guide to punching holes.
This method is the automatic default one for any 2-color DBJ knit on the Passap.
Each color in each design row will be knit with each pair of consecutive color passes. Completing one design row containing 3 colors will require 6 carriage passes, 4 colors 8, and so on.
The built-in color separation in electronic machines wherein each of only 2 colors in each design row knits only once does not apply when using more than two colors,  though it is possible using Dak or by downloading a special card reader technique to program separately from the design when using the Passap E6000 in addition to the pattern repeat.
This separation of a 2 color pattern results in an elongated version of the design regardless of any dbj backing used.
Begin with a 2 color image,  an extra column of pixels is added here as well:
A: multiply YX4 to 13X48
B: mark alternating pairs of rows in the extra column with a contrasting color
C: following the color cues on the far right column, on rows with no added color use the pencil tool to replace black pixels with white, leaving only the orange cells
D: on rows marked with the third color replace the orange pixels with white, leaving only the black pixels
E: crop the image eliminating the extra column
adjust the remaining orange color to black
index the result to B/W, and the image is ready to save and use The difference between single repeats for each type of fabric, no further elongation is required. A: mosaic, B: DBJUsing layers in Gimp opens up the possibility of several color separations for fabrics using only 2 colors.

Both img2track and Ayab are capable of opening 2 color images.
In img2track this is what would appear, after the download the KRC function needs to be activated in the knitting machine.  Ayab: the repeat should be programmed in width equal to the number of needles planned to be in use. The color change happens as the file is loaded into the program, the ribber classic option is used to render results that would match the KRC knitting machine selection after an img2track download. Here the repeat is also tiled in height.  My personal preference is to work with images designed in black and white. With the 910 presently stored, my blog swatches are knit on a 930 using img2track.

A note for Mac users like myself using desktops with the M1 chip and Mac OS Monterey. Img2 track requires an FTDI driver for its download cable, on June 6 finally released a beta version of a more recent driver, I do not plan to install it at this moment, function in the upcoming Ventura OS would be unknown.   Ayab does not launch automatically. These are the steps necessary to run the program, following suggestions by Adrienne Hunter via the Ayab FB group:
open a Terminal window (Applications/Utilities/Terminal) and type these two lines:
cd /Applications/AYAB.app
./Contents/MacOS/AYAB
The app may also be found and then opened via using Spotlight search if you prefer  Once the program is quit unless you choose to keep the terminal icon
in your dock, it will disappear and the above process will need to be repeated. Once the text has been entered, and Ayab has been launched, a message similar to this will appear, showing your last log in. To launch Ayab again, simply use the up arrow key and hit return to repeat the command  Creating an AYAB desktop shortcut for Mac that will work without opening the terminal each time
Using Finder, open Applications and find AYAB. Right-click on AYAB and select “Show Package Contents”.

Locate “AYAB” under MacOS. While holding down the command and option buttons, click and drag that icon to the desktop. This will create an ayab shortcut that does the terminal stuff for you you can change the icon by copying and pasting the icon image in “get info” but it works fine without it. These icons will appear in your dock after double clicking on the icon   The ayab window opens with only the load image option highlighted Click on the load image file to open an image, and the remaining features of the program will now be available If you quit ayab, the terminal window remains active Quitting terminal called up this window for me only the first time I did so.

Visualizing maze or mosaic potential from tuck or slip stitch repeats

I have written extensively on mosaics and mazes, color separations required for drawing their motifs, and visualizing the resulting patterns while planning slip stitch or tuck repeats. A recent exchange with a knitting friend, Tanya Cunningham, brought up her idea of using Gimp to investigate the potential of self-drawn tuck patterns becoming pleasing mazes or mosaic designs in color. Tanya has worked extensively with img2track and can be found in the FB group and Ravelry. It had not occurred to me to reverse engineer designs for this purpose. Tanya uses Gimp in a different way than I do, I am hoping she will share her process for this purpose when documented.
I have grown comfortable and fast with the combined use of Numbers and Gimp to achieve what I desire in terms of color separations. At the moment, on the assumption that estimating the overall shape is the goal, a black-and-white processed rendering may be a sufficient representation of the result.

Punchcard books are a great source of “safe” tuck designs. The best are those that have columns one stitch wide by 2 rows high. They are also more interesting if there are areas of solid black. Patterns from publications intended for use on electronics are often color reversed to start with in order to minimize drawing pixels or to make the design easier to read and will have lots of blank areas. Punchcard users would need to punch the ground as opposed to the design, electronic users can achieve the goal by the flick of a switch or a quick software command. For my first series of steps and methods, I am using the repeat that appeared as a knit using different settings in the post on mazes and mosaics from universal patterns.
Presented on the left, the repeat would be suitable only for thread lace or FI with very long floats. Color reverse allows one to use it for tuck and slip stitch, whether in one color or with color changes every 2 rows. The color separation to approximate the result with color changes begins with the same process as that used for designing mosaics. Once the image is rendered as a correct B/W PNG with no apparent errors, it is copied and pasted on a larger canvas, and the mode is converted back to RGB. The red cells make it easier to keep track of rows that need to be color-inverted. Using the shift key and rectangle tool, multiple pairs of rows can be selected sequentially and color inverted. Beginning the selection with the very edge of the black squares on the left does not interfere with changing the color of the extra columns on the left side of the design. If pixels are added accidentally drawn in any of the 4 extra columns on the left, they can easily be removed when the completed conversion is cropped to selection for the final repeat. The completed color separation can then be filled to match imagined colors.
The repeats of the final knit pose the problem that results from working on a square grid and comparing the results, which usually form a rectangular one.
The representation of the linear patterns on the knit side of the piece cannot factor in some of the added distortions created by the stitch type used.
I process my images in Pages or Numbers, depending on which document contains my most recent work and happens to be open.
The final may be rescaled in Gimp.
Most knits approach a 4:3 ratio, with gauge variants in highly textured fabrics.  To preserve a clean design, tile and save the original, screengrab the resulting image, load it in Gimp, and rescale to that ratio.
Repeat the motif for the same number in both height and width when tiling it. The colored versions before and after scaling, compared with the slip-stitch swatch. It is possible to produce a rectangular grid to start with on which to draw in Gimp, but the larger canvas size occupies a significantly larger space on the screen, complicating the process. For small designs, however, that may be an option to give one the sense of aspect ratio for the design in the final knit ie in representational FI. To resize the grid in uneven proportions, the chain-link below the spacing values needs to be broken This repeat is designed for an electronic, and requires color-reverse.
Since it is 24 stitches wide it may also be modified and used on a card.
In this instance, the original marks for rows and stitches are single height.
The image is processed, matching the original, rendered double-height, color reversed, and then alternate pairs of rows were color inverted to render the repeat used in the test swatch Once again, the possible change in scale is estimated. The repeat though only 24 stitches wide, is 92 rows high. On the left the repeat is shown as it appears on a square grid, to its right is the scaled 4:3 version, in a pixel count approximating the size of the swatch. It takes a bit of squinting to see the pattern more recognizable in the longer repeat in the larger tile The swatch was pressed, becoming wider than when first off the machine. It was knit using the slip stitch setting, which could also be executed in a tuck stitch, and would both widen and shorten the fabric and make the purl side more interesting.
The software can provide a preview of the result far more quickly than knitting samples, but again, the previews are only approximations of the scale, and cannot show distortions to lines as one adds more texture.
Repeating the process starting with a diamond shape that as given is only suitable for thread lace or FI with problematic floats,  and with a check tuck pattern that may change in aspect ratio considerably when knitted The proof of concept swatch, knit in tuck stitch, begins to show the distortion by the stitch formations, textures vs plain knit, easily seen at the top edge. The bind-off is around 2 gate pegs in order to allow enough stretch.  Anyone familiar with either or both programs may find this a very quick way to visualize the scaling and moving of motifs within DIY designs and their possible outcomes prior to test knitting

Mosaics and mazes charting meet Numbers, GIMP 3

If working in Numbers, the solution to doubling the height of the final repeat for mazes or mosaics may be achieved by simply doubling the height of each cell prior to screen grabbing the table and processing the resulting image in Gimp. Here the cells for a single repeat in the table on the left are copied, pasted, and altered from 20X20 pixels to 20X40Working in 1800 magnification, using rectangle select, every other pair of rows is chosen and then color inverted. B: the process continues for the height of the repeat. Until each new pair of rows is selected fully, the last color inverted pair is bordered in a dotted outline C, useful in tracking the last worked location. As the subsequent pair of rows is selected fully, the dotted border will disappear. The processed repeat  Its tiled visual check  Proof of concept: the bottom half is knit using the slip stitch setting, the top half in the tuck setting. The added texture on the tuck stitch purl side makes the fabric a more interesting, reversible one, and wider than its companion.  For a different way of working with two-color initial images using only Gimp, see tips in Gimp update for Mac2.The process used on the beginning repeat, redrawn in 2 colors and then, in turn, elongated X2 or drawn double long to start with, tiled to check alignment. There are 2 options for altering colors in 2-row segments to achieve the separation, the first is color invert, the second is value invert, found in the colors menu. Both require color filling in of cells so as to obtain the final BW image, the value invert option, in this case, would require only filling in the green to white, but in managing larger images I believe having the additional colors make the process easier to track accurately. The color invert option will substitute a third color and white on every other pair of rows. Flood fill the original color 2 on rows containing black pixels with white, then fill color 3 pixels with black on rows containing white pixels: The mazes that are often seen in game-playing, puzzles, historical sources ie in Chinese design references, may not work out for knitting with this method, the result can be quite muddied.  I recently found a new to me online maze generator http://www.ludiculus.com/maker/mazes.html.  Changing the pixel width by default also doubles the image in height, making smaller designs for knitting problematic  This was a quickly drawn maze using it, shown with its cropped repeat on the right, then tiled. Numbers processing to ready the repeat for final gimp editing: The repeat when tiled predicts muddied results which are noticeable in the knit swatch. Because of the side-by-side areas with multiple white cells, the slip setting is used, not tuck. The single slipped lengthened stitches do not produce an easily recognized secondary design on the knit side Getting back to clearer pattern results: when using electronics, it is possible to create far wider and taller repeats for download. The technique to achieve them uses the same process. That said, there are quicker ways to attain the final repeat illustrated in the 2024 posts on using Gimp color to alpha through the Layer> Transparency option or Colors> Color to Alpha.
A new working repeat, 38X34 pixels: its tiled appearance  My starting table in numbers with hidden rows, beginning to isolate a smaller repeat the isolated repeat, double-length the color separation in progress
When knit, that white cell pair of rows break up the overall shapes and shifts the pattern in the top and bottom half When I tiled my next draft, I decided I preferred a cleaner join at the center The final adjusted repeat knit using the tuck stitch setting in both directions, KCI, first row left to right, leading with the dark color and here with the lighter color In progress, on the km  the relaxed, 3D-ish view on the reverse why projects can take longer than planned The finished, relaxed scarf with pressed edges only, retaining the conical striped formsThe repeat knit double length, changing colors every 2 rows, becomes something quite different, with a sharp curl to the purl side

Mosaic and maze inspiration from additional sources

Reviewing properties of both: maze patterns have long vertical and horizontal lines broken by regular gaps and the pattern lines change course from the vertical to horizontal, and vice versa. Maze cards can be identified by completely punched row segments, some alternating with every other square marked for two rows, usually geometrically shaped. Areas of stocking stitch produce horizontal colored stripes, and alternating pattern stitches that slip or tuck cause the vertical stripes, which are sometimes pulled nearly diagonal by the influence of tuck or slip. The fabric will be unbalanced because the number of needles slipping or tucking will not be the same on every row. Odd rows usually form 2 color horizontal stripes, even rows vertical stripes, with color changes occurring every 2 rows.
Mosaics have a brick arrangement (tessellae), with clear perimeters and cores, and stepped diagonals (frets) that are partially formed bricks, their positive and negative spaces are created by the use of contrasting colors. The stripe sequence is not as obvious. The punchcard does not resemble the original design.
In single bed work, the reverse of the fabric will show the original design in the texture of its slip or tuck stitches. There usually will be no floats longer than one or two stitches.
The knit side may look like a fair isle but the back lacks any long floats, hence the name “float-less fair isle”
The row gauge is compressed. Tuck fabrics are short and wide, slip ones tend to be short and thin. Some patterns elongate in washing. The tension used is usually one number higher or more than that used for stocking stitch for slip patterns to reduce their narrowing. Tuck knitting may need adjustments to lower tensions. Smooth yarns in contrasting colors are the easiest to establish an easily recognized test pattern, the choices that follow may then be far more personal.

After a while repeat units begin to become familiar. Pondering possibilities: Here the design knit as a fair-isle pattern would produce long floats, going through the steps of converting it for “floatless fair isle” proves of no benefit.

I previously wrote about the use of weaving
drafts as inspiration for other textile techniques, ie. knitting.
Endless published drafts may be found online or in books that might be interpreted for use with mosaic/maze single bed knitting. Having electronic machines available lifts restrictions in pattern width, while repeats too large for narrow items such as scarves may become useful for shawls or blankets. One such repeat,  with .pngs shown for both single and double-height:

This repeat is 36X36 before being lenthened X2 

A different sort of challenge was posed by this 18X18 image with a row shift in areas with a large number of both filled-in or blank squares. As one moves up its magnified version in Gimp it becomes apparent that a row will have a very long float in one of the two colors. One option is to skip that row, resulting in the green gridded repeats for the converted motif both shown both for single and double length. The result in the knitting test swatch produces an unplanned color shift which could be declared to be a design feature, or one can continue with editing the inspiration source. Repeating the separation process with a new graph produces a workable cousin to the original Generally when creating these patterns on Brother machines, patterning selection varies for each pairs of rows. I got distracted while making the above swatch by a phone call, got to the point where there is a very obvious solid black all knit row in the repeat, but “forgot” its presence. I assumed I was having a selection or a carriage issue and scrapped the knitting off. Note to self: “remember to always check the programmed design before you do that again in the future”.

 

 

Mosaics, mazes, and DBJ charting meet Numbers, GIMP 2

Please see the post Gimp Update for Mac 3   written in December 2022 for a simpler and quicker method of color separating maze/mosaic repeats using only Gimp and related swatches. 
I shared some working methods to achieve these color separations in 2019/06/29/mosaics-and-maze…numbers-and-gimp/. Mosaics and Mazes came on my radar once more recently, Numbers and Gimp have both been updated, and a few more ideas have occurred to me for managing the necessary color separations. The process as described here assumes that there already is some comprehension of GIMP and a spreadsheet’s basic functions. These are 2 more samples from Barbara Walker’s book on mosaics, offering the repeats in both 16-stitch wide and 24-stitch versions. It is always a good idea after isolating the repeat to tile it in order to get a sense of how multiples line upI was lazy about doing that with the first version of the colored repeat in Numbers and got the result in this swatch  due to a missing black cellThe second try, see edit below to amend another missing cell  Beginning with the long method to create the design repeat in the color separation suitable for elongated dbj: the built-in color separation in most Japanese machines for DBJ (179 and color reverse in Passap) will knit each color in each design row only once, as happens on the single bed in knitting fair isle, which in turn is far quicker to knit in that setting than by using slip stitch with color changes every 2 rows. The first preselection row is from the left to the right, the first color knits once before colors are changed every 2 rows.
The dbj color separation that knits in each color for each design row twice begins with preselection from the right and continues with color-changing every 2 rows. The produced image will be twice as long as the original design, not desirable for keeping the aspect ratio as close to the original as possible, but a necessity in creating some alternative types of fabrics.
To start, create a table, making certain that cells are square and equal in size, height, and width. I prefer 20 X20 or more when working with small repeats. The zoom factor can be adjusted, increased for more visibility, and reduced prior to screen grabs that are planned to be further processed in Gimp. At less than 75% while creating charts, adding numbers or text, and sometimes changing the qualities of individual cells is harder to achieve. Large-size images may be scrolled through during the formatting process The working design repeat is 16X16. Create a new table that is 16 cells wide, twice its height, 32.  While holding down the command key, select all the odd-numbered rows planned for the final chart repeat, any errors can be corrected by clicking again on the same spot, still holding the key down. The process may be done in steps, releasing the key in between selecting groups  Choose the hide rows option, hiding 16 rows, Fill in cells the chosen 2 colors Add a column to the table. It will be colored, select the column and choose the no color fill option for it, then resize far wider by clicking and dragging the symbol 
at the upper table right to allow for copying and pasting the full repeat more than once.
Select the chosen repeat in 2 colors, copy and paste it to its right. The rows are re-numbered in the new “chart” thus providing a new set of even/odd-numbered rows. On the new odd-numbered rows, select by holding the command key, choose black squares on each now odd-numbered row, and used no color cell fill option to render them white. Release the key at any point to work on gradually selected groups of cells.  If there is an error, while still holding the command key click on the individual cell or cell group again to erase the action, continue the process. Again, holding the command key selectively, on even-numbered rows add colored cells immediately above any empty cells in the row below.  It could be done all in black, but for me, that becomes difficult to keep accurate when separating large repeats. With some familiarity with spreadsheet creation, this can be fairly quick work. Copy and paste the table content once more. In the new table holding down the command key, on even-numbered rows change colored squares to black resulting in the repeat on the far right. The latter in turn will need to be doubled in height once more prior to knitting the final fabric, whether in the software or by the machine in the downloaded design To produce the .bmp file: copy and paste only the BW portion of the above table once more. Using the cell format option, remove all interior borders,  and if you prefer an outside guide, add an exterior border try zooming at 75% zoom, screengrab the table content, with an added blank border surrounding it, and import the result into Gimp. Choose crop to content, which will eliminate the extra white space around the image The final image needs to be double-height, so using the scale option choose image scale to 16 by 64 using the broken chain link prior to entering your numbers. These were my steps in scaling, I always check one more time for image size prior to saving. That is reflected in the last pair of numbers, with the now intact chain link symbol

When I first used Gimp I devised and explained this method for mosaic color separations in prior posts.  The expectation in working with such repeats is that on any rows there will be no more than 2 white squares marked side by side. On odd-numbered rows in the separation, the contrasting color squares slip, while on even-numbered rows the black squares slip. On odd-numbered rows, the main color (black squares) knits, on even-numbered rows the contrast color knits.
I think of row one/ odd rows as needing to knit black squares, row 2, and even rows having to knit white squares rather than marking in the traditional manner for slipped stitches on each row. I now have found a far quicker alternative to color separation for mosaic knitting using only GimpWorking on the black and white indexed repeat, using a magnification of at least 1800X. Using the rectangle select tool choose every other row beginning with the second one in the chart. That row will be highlighted by a white dotted line. Choosing will swap black and white cells in that row. Continue the process on every other row. It is not necessary to select the tool each time, as you advance and select the next row, the one just left remains briefly outlined in white dashes, making it easier to advance correctly in the design.
Import the black and white table, process as described, scaling for my final image to 16X32: This repeat posed by a quandary. The file may be used as-is and doubled in length after download. For doubling the height in Numbers, prior to importing the final screengrab into gimp, please see post:  2021/01/27/mosaics-and-mazes-charting-meet-numbers-gimp-3/
Because of my personal preference for not using elongation when knitting pieces in these techniques, I tested doubling height in Gimp with no success at all. However, I was successful in doing so using 2 paint programs, both available for free download for Mac. The first has an amazing range of features, including the illustrated resizing options https://www.arahne.si/products/arahpaint/

and https://paintbrush.sourceforge.io/downloads/, which allows for scaling by percentages or pixels Comparing the results for the elongated repeat, errors in the first are obvious, there should be no white squares anywhere repeating for more than 2 rows Proof of concept December 2022: knitting the above again intending to share the result in Instagram, I noticed that 3 stitch/ row color block, which did not bother me at the time, but with the float showing behind the wire, I went about inserting that center cell. The red pixel in the image on the left marks the trouble spot. The remaining images illustrate using my latest Gimp separation method to rework the original png: comparing the final result to the one in this post:
The new file prior to lengthening X2,  double lengthReturning to 2020:
A review of a design from 2012/10/15/mosaics-and-mazes-from-design-to-pattern/, separated this new way the repeat charted in Numbers tiling for viewing the repeat alignment revealed errors that will result in missing colored squares in the final fabric, which may not be noticed until after eyeballs have had a rest. The amended repeat was color-separated working in indexed black and white and shown compared with the punchcard  Here the final .bmp  repeat is also compared with the color image in the previous post. It will need to be doubled in length for use with the color changer, the first preselection row is from right to left. End needle selection will ensure that each color knits the first and last needle on each side of the piece. The double-length repeat, 24X56 Another very quickly separated repeat copied from 2015/10/03/working-with-generated-mazes-charting-1/

adapted for maze knitting, eliminating long floats, to be lengthened to double-height drawn double-height via a paint program Because there are no more than 2 white squares on top of each other, and no two side by side, I tested the pattern in tuck stitch, which produced some added texture. I had a major aargh moment with yarn where dropped stitches are seen at the top of the swatch Using the maze generator by Laura Kogler, the larger BMP newly created with the program was imported into Gimp, explored in two renditions, eliminating double lines in the one on the right The proof of concept swatch for the version on the right, knit in tuck stitch the double-length BMP ready for knitting,  14X68

Designing your own motifs in expanded graphs: start with a template for either of the 2 grids shown below,  and fill cells in or remove them. Remember these charts, unless knitted as a machine or software-separated dbj, will require a careful color separation.  Beginning ideas for motifs, borders, and alphabets

A collection of previous posts on this topic in reverse chronological order
2019/06/29/mosaics-and-maze…numbers-and-gimp/
2015/10/21/working-with-gen…-gimp-charting-2/
2015/10/03/working-with-gen…mazes-charting-1/
2012/10/15/mosaics-and-maze…design-to-pattern/
2013/05/06/mosaics-and-mazes-drawing-motifs/
2012/10/15/mosaics-and-maze…design-to-pattern/
2012/09/22/mosaic-and-maze-…-on-the-machines/

Mosaics and mazes charting meet Numbers, GIMP, and DBJ

A category search for machine knitting/mosaics and mazes design will lead to my blog posts on the topic. Among later posts, one method for color separations for this fabric using Gimp alone may be found in 2021/07/18/gimp-update-for-mac-2/.
Previous posts on working with Mc Numbers include: knit charting using Numbers 2  which covers basics, keyboard shortcuts, and more,
Numbers to GIMP for creating images for electronic download, charting knits color separations 2, charting knits, color separations 1, lace mesh motif charting, charting knit repeats using numbers 1, visualizing knit cables, knit graph paper 

Rules for and appearance of designsMosaics and mazes: machine knits_ from design to pattern

To knit these fabrics use one light color and one dark for major contrast is recommended. Matching the dark yarn to dark squares and reversing their positions may produce interesting optical variations. The resulting knit has reduced floats and is not as bulky as traditional Fair Isle. Many patterns published in punchcard machine pattern books will produce such patterns when knitting on a single bed, changing color every 2 rows. White squares need to be 2 rows high, no more than one square wide. A page from one such reference: What appears as a maze designs in the swatch photos below would actually be unsuitable for use in the mosaic separation discussed in this post. The cards are designed for tuck (or slip) with color changes every 2 rows. The approach for planning and charting out such fabrics would be a very different one

There are a few rules in designing your own: in mosaics, the odd grid rows should contain single or dark-colored squares plus any cells used to create horizontal lines. The even grid rows usually have single or adjacent light squares but only single dark squares. As with any other fabric access to electronics allows for use of small repeats that can be color reversed or lengthened X2, whereas punchcard knitters need to meet the usual constraints in motif size in width and height. Tile features in software can often give clues to errors such as skipped cells or edges at top and sides of repeat that do not line up, avoiding having to actually test the repeat in knitting to evaluate the same.

Pre-drawn motifs that require color separation are available in a variety of sources. Kathleen Kinder published 2 books with repeats one for 24, the other for 20 and 40 stitch punchcards, including isolated electronic repeats as well.

The original “swatch” inspiration for this post and its repeat were pictured in Mosaic Knitting page 110the numbering system reflects every other row worked alternating sides of the work it is shown here with a superimposed table grid with its cells outlined in a thick border and positioned in front of a scaled screen grab of the original motif (arrange/ aspect ratio turned off)use command key to select a series of cells to be filled in with color, I chose to use black the cell borders can be edited as wished. Here borders were removed by selecting none, then, in turn, the outer border was highlighted in an easy to identify a thicker red line

Below are more variations on borders and numbering for the start of the machine knitting repeat. Adding digits to the Numbers original repeat serves as a guide to appropriate size scaling in GIMP. One way to obtain the repeat size is to type digits in at least 2 cells at the desired location in any row or column. Select both cells, click on the yellow dot, and drag it to the last cell in the series here I went into autopilot: the repeat is isolated. The lengthen X 2 requirement can be achieved later in GIMP or as here via the table/ arrange/ size option in Numbers (wrong step for mosaic/ mazes)
I change the outer border to one point dotted to have a guide for a screengrab The captured image may then be imported into GIMP, image mode is changed to color indexed, B/W bitmap, and it is scaled to the appropriate size. The view grid, snap to grid options are in use.
I worked in 1800 magnification, created a new canvas 2 pixels wider than the original on the left, copied and pasted that image onto the new canvas. In the center illustration, RGB mode is once again in use. The added green pixels serve as guides for using rectangle select to capture each of the rows containing them in turn and then using invert value from the colors menu to reverse background and foreground within each of those rows.  The completed color separation is shown on the far right, with those 2 extra rows on its left side the last image needs to be once again converted to BW mode. The 2 extra rows of pixels on left are cropped off, the image is scaled to twice as long for use with the color changer, and the original 12X14 repeat is now 12X56
the actual BMPthis is the charted and tiled original repeat. There are classic differences from what is typically thought of as “floatless fair isle” in it. The very last row ie is in one color only.  When those 2 passes are made with the “no knit” color with the change knob set to KC I, the first and last needle will be selected. Push them back to B position prior to knitting the next row to avoid side to side floats.  Because of the maze component floats of as many as 7 stitches are created on the purl side in one of the 2 colors. A quick proof of concept swatch: this is a slip stitch fabric, note the difference in width between the patterned area vs the plain knit. If one has a ribber and the appeal lies simply in the lines created by both mazes and mosaics, those features can be retained with DBJ, and the fabric will lie flat. There will be limitations as to the thickness of the yarn used. a “pretend” longer repeat
The question has come up in forums as to whether the DBJ separation can be used for mosaics and mazes. The “Japanese” one, which prevents elongation by knitting each color for each row only once does not since these shapes rely on knitting the same needle selection twice in each color. The default separation in the Passap or the designer self-drawn one that will knit each identical spot in the motif separation twice. The design is elongated. Susanna wrote a technique for use on the E6000 for having the console perform the color conversion for true mosaic knitting. The repeat shown earlier in this post separated for DBJis compared here with the earlier wrong separation for “mosaic knitting” and found to appear identical. The process was a quicker way than that of dealing with different colors for ground and design
different pairs of colors, same results Back to the drawing board: row height is as in the original repeat being extra careful, not necessary, the process can be inverted once more to check the repeat color separation the actual knitting repeat, double-length before downloading to machine the corresponding proof of concept swatch,  with shorter floats than when the DBJ separation is used single bed tiling of the original repeat and its color reversed image illustrate the optical difference between switching dark and light color starts This repeat is from Kathleen Kinder’s (24-stitch) Floatless Fair-Isle book, p.86the repeat of the design separation on the right is intended for use in electronics with color reverse and double length chart separated using GIMP for mosaic knitting matches her repeat Recently on Facebook mazes turned up as a topic in machine knitting once more. Most maze generators online that I have found are designed for printing out game solving images ie here is one from http://hereandabove.com/maze/mazeorig.form.htmlfor knitting purposes unikatissima and Laura Kogler offer alternatives. Years have gone by since I first wrote on mazes and mosaics. The repeat worked with below was used in my post. 

Here I am revisiting the same image. To begin with, a repeat is isolated and processed in numbers (top row), and then in turn in Gimp. Always tile repeat to check for any errors and to see if the final image represents what was planned.
The repeat (8X16) is then doubled in length for knitting after that single all-white row was edited out (middle images). The repeat is now 8 rows wide by 32 rows in height
One of the yarns is chenille, the other a wool. The chenille is slightly thicker and fuzzy, so some of the yellow rows are almost hidden but the pattern is definitely there. Here the design is knit using both slip (bottom) and tuck (top) settings. Again, there is a noticeable difference in width produced by each stitch type. Observations: make certain that after the image is isolated in Numbers cell size is converted to square/ equal measurements in width and height before importing and scaling its screen grab in GIMP if not already so. It will likely load in RGB mode, convert to Indexed before scaling. Added colored squares are only possible if you return to RGB mode. After rows with colored squares are cut, return the image to indexed before saving as BMP for knitting. If any pairs of rows do not have 2 consecutive rows of cells in either color check your pattern. In DBJ the final repeat should be 4 times in numbers of rows in height to the original one, and thus divisible by four.  The separation first doubles height for each row for 2 colors. Then height is doubled once more to allow for color changes every 2 rows. In Mosaics and Mazes, the color reversal happens on every other row in the original design. When that is completed, the height will be doubled for actual knitting to allow for color changes every 2 rows, with the final row count double that of the original motif. Rules for tuck knitting apply here as in any other technique. If white squares in the final chart have black ones on either side of them, the appearance is that tuck would be possible. Examining needle preselection is an easy way to assess that possibility.  Reversing the colors used in actual knitting may yield interesting changes in the appearance of the fabric. 

Julie Haveland Beer shared a file on how to Convert Mosaic Knitting Chart to KM Skip Stitch Diagram (shared with her permission), as mentioned in my post on numbers-to-gimp-to-create-images-for-electronic-download/