Over the years I have written on an assortment of methods for color separation in knits including DBJ, a summary post with links to previous shares: dbj-and-color-separations-some-previous-posts-links/
and in the-start-of-a-blog-index/
A variety of textures and patterns may be used to achieve fabrics that are very different in appearance, using a very simple pattern along with cam button or lock setting changes. The first chart was generated at that time using Intwined Pattern Studio, a program that for a time appeared to be very promising and then moved on to lack of updates for Mac making it useless in 2013, followed by none for Windows as well, with no successful use of it reported in forums in years, but one may still purchase it 
The manual color separation method for punchcard machines.
The elongated X2 repeat version of the triangle drawn in Gimp 
As for more than 2 colors per row, performing the color separations may be achieved manually, various software is now available for performing the work in instants.
Ayab offers an elegant color separation solution, heart-of-Pluto, that will knit single passes for each color per row on the front of the knit, resulting in 3 color patterns with limited design stretch, and no worries about the placement of one color over any stitches preceding it in the same color on the previous pass.
The difference in the same design being knit with the standard, elongated version, allowing for two passes with the same color before each color change and the Pluto version. 
knit using img2track, the vertical stretch is manually set to X2, 
A “hack” 2021/01/24/img2track_multiple-colors-per-row-dbj-each-color-knitting-only-once/
For more information on the various DAK separation charts and related swatches including limitations encountered, see post: DBJ, more than 2 colors per row 4
There is a Russian punchcard site that will allow entering personal repeats or selecting one from their extensive library, where it is possible to obtain related 2-color dbj separations as well. The punchcard color separation may be created manually, a slow process, while the punchcard templates in Dak are achieved with a few, quick clicks of a mouse. The repeat may be created as a graphic file, in my case a png created with Gimp, the elongation in Arah because Gimp fails to scale small repeats cleanly. The image may then be opened as a graphic file,
stitch and row counts should match, and save the stp 
if experimenting with changing selections and this window appears it is OK to click on No 
The separation methods in DAK:
Method C separates each color row into separate rows of knitting, rows do not have to be repeated in pairs, and the double-length switch will need to be used in Japanese knitting machines 
The elongated triangles repeat template is different from what would be produced with the above set at double length, may be used as is to produce a variety of fabrics including quilting
Yarn choice and design make a big difference. Here the yarn is far too thin, and the repeat too narrow in width, but the possible result is illustrated. The main bed is set to slip in both directions throughout. The ribber setting needs to slip in both directions for every other pair of rows. When the ribber slips, the main bed will knit the color that will create the pockets, where there are many single stitches selected here, the KC was set to KC1. When the color is changed and the ribber is set to knit again, stitches in that color will knit on both beds, sealing the fabric in those areas and forming a solid color background on the reverse side. Here the white forms the pockets, and the floats after a pair of passes are seen in this photo. 
Because the yarn is so thin there is a considerable grin through on both sides, the areas marked with arrows indicate where the white pockets were lightly stuffed with yarn ends 
For a review of quilting on machines including Passap see 2018/02/15/revisiting-machine-knit-quilting/, and using a second knit carriage with a modified sinker plate for knitting stitches on main bed only, making ribber settings fixed throughout, and allowing for tension adjustments for each color yarn.
Methods A and B are both used in Japanese machines when each color is intended to be knit for 2 rows with color changes on the left.
Method A works on pairs of rows. If the pattern does not consist of identical pairs of rows there are likely to be yarn error messages that resolve when the design is lengthened in height X2.
The original triangle elongated to 8X16 
If pngs are created outside the program, they may be doubled in length unless the repeat is designed that way. 
The associated menu options in Dak when the plan is to work in double jacquard 
How the different jacquard setups process the specific repeats:
Method B creates the same separation as the default built-in KRC one in Japanese electronics. If knitting DBJ it may be used with DAK if the pattern is downloaded as fair isle but the machine will then need to be set for dbj. If additional colors are used, pairs of rows will follow a single pass for color1. The print preview templates, if generated within the stitch count restriction for use on punchcards, may be used as guides for punching the required holes, this would be the card for that 8X8 triangle repeat, a tad shy of the recommended 36 rows, 
Passap card reader techniques saved from long ago experiments. 
Other separation methods in the Passap are handled by the console with the entry of specific knitting technique numbers.
That said, the DAK color separation is applicable for printing reader templates if still using Passap E6 reader cards or punching for the Duo with Deco.
Method C see the top of the post
Method D separates each color into a separate reader card and is used to download to the Silver Reed PEI or the Passap E6, appears to use superimposing of layers, and matches method 4 in my post.
Method E is suitable for machines with a color changer on each side, like the Brother CK 35. It works on pairs of rows and separates each row into a pass with each color. A 3-color jacquard would have six passes with colors separated as follows: 
Method F is a Half-Milano separation. Each pattern row is separated into a pair of passes for each color, but the second row for each color has no patterning, so the ribber stitches only knit as the carriage returns to the left side, a possible way of creating repeats for drop stitch lace on Brother machines. 
The elongated triangle template was split into 2 pages for viewing, they are combined in this image 
This may be the associated Passap Reader technique, but I have no way to test it 
Processing the template using numbers: a table is created twice the length of the 8X16 triangle repeat, followed by hiding the 32 odd-numbered rows, positioned in front of the scaled punchcard template, stitch markings are traced 
the rows are then unhidden, the repeat is checked, matched here to the F jacquard separation in Dak
The numbers table is processed in Gimp to obtain the png for knitting the now 24X64 pattern 
Proof of concept swatches: the long stitch in 2 colors, 
and the pattern executed as a tubular FI knit: I had yarn issues, hence the dropped stitches. Both swatches were knit to approximately the same point in the pattern repeats, there are obvious quality differences in width and length. In tubular knits, there are differences in the width and height of the knit on each side. The front is a slip stitch with floats, drawing the fabric in, while the ribber knits every stitch every other row. With a good choice of yarn and pattern, loosening the tension on the top bed may ease this problem. As often happens, casting on and binding off need special considerations ie to allow for any fabric stretch when off the machine or to leave a tubular knit open at either or both ends if that is the goal. More info on tubular knits including on Passap
DAK has been a purchase made out of curiosity, and my use of it has been very limited since my designing needs are met by using other programs that are free to users and generate and accept files in multiple formats, while the Brother Knitleader or even simple use of the magic formula solves knitting any desired shape in any gauge.
That said, if one can generate the templates produced in DAK, the screengrab of the result may be used to generate a PNG with ArahPaint using the weave-from-grid feature that is then knit-ready on any electronic machine able to accept downloads. The method is far quicker than using Numbers and Gimp. 
When automating the repeat edits are possible and very easy using the lace module, these first drafts were created in Numbers, 
I have to admit the first time I tried to knit both the associated png, mirrored and not, I experienced patterning errors. Whether due to operator fatigue, static, or any other possible cause, on a different day both designs knit successfully, and my appreciation of the module is growing steadily. The results for this, a complex shape, are quick and awesome when compared to the amount of time it would take to draft the pattern outside the program.
An stp was created, the template is marked 74 rows in height, filled in as the stp was generated, right side facing 
Numbers and Gimp reduced the template to a png 14 stitches wide by 52 rows long, needed to be mirrored using the number one button on the 930 for successful knitting, 
matches the original illustration. Dak makes slight modifications very easy. The untested brick repeat, 28X104, developed using Arah followed by its png 
changing that central shape
The amended design drawn in repeat in dak visualizing the knit, 
The print preview template: 
the resulting png, 14 stitches by 68 rows, also knit using the number one button on the 930 
the proof of concept swatch 
The brick repeat developed in Arah, now 28 stitches by 136 rows, 
its png 
comparing the initial three knit results for differences, the samples were knit using the same yarn at the same tension 
A test for the second brick repeat, here visualizing results with a screengrab of the stp. 
The test swatch is for a single repeat width, the initial yarn used ran out, hence the color change, the second yarn was thinner and broke, but there is enough to get a sense as to how the overall alignment of the knit shapes will appear, including that horizontal chevron between the shifting leaves. The png required mirroring when used on the 930. 
A proof of concept swatch: the yarn was too thin for the many transfers and broke, so on the right, there are fewer stitches than initially planned. At the bottom there is a single instance of 2 rows knit after all the transfers, there are 6 rows knit after each transfer series in the remainder of the swatch. Color changes could be added in multiple places to interact with the wavy shapes 
it would need to be drawn eliminating the pairs of blank rows between transfers to match the original repeat because all those carriage passes are consecutive. Drafts with no blank rows between alternating transfers are not accepted by the program and ruled out in any template preview as well. 
The complexity of working with a “simple” repeat: over the years I accumulated a notebook full of copies from Japanese magazine pages with what I believed to offer interesting potential, this repeat happened to be one. The markings for the knit rows on the right, and the two blank rows at the bottom identify it as suitable for Studio punchcard machines, and it would appear to be easy to translate for knitting on Brother thanks to those 2 blank rows between transfer cell markings. 
Developing the Brother repeat in Numbers for beginning with transfers to the left. The repeat is recognizable as a mesh variant, more information for mesh design repeats may be found in the 
the repeat on the right was created in Gimp. 
The 12X18 png 
was mirrored for use on my 930, some cables were added. A 1X1 crossing in the thin yarn used in the sample would have been nearly invisible. The placement, in this case, is at the top of the full repeat, after the first knit row before returning to transfers for design row 1, an easy way to track the hand technique. The 2X2 crossing used might need help with definition and placement in a wider vertical knit strip 
Creating the stp: the size of the png was used to create the image file, which required cropping, in Dak this would be the menu language after activating the proper tools. the stp size is 12X16, 
The template generated for a Brother punchcard machine illustrates the problems and some of the confusion if the template repeat is used for actual knitting, especially on the punchcard machines. Drawing the eyelet and dragging the mouse one cell to the left is the intuitive way to draw for transfers to the left. The symbols appear to be right-side facing by default and if they are in turn mirrored by the program prior to saving, when the templates are generated, the intent for use of the design would match. The numbers on the left are in the punchcard template, adjusted by cropping the two extra rows in the Brother electronic template by the software, do not reflect the actual design row numbers. The starting row is wrong for the Brother lace carriage operation from the left to produce the first row transfers to the left in actual knitting. As far as determining sequences for knit row placement, that is left up to the punchcard knitter’s experimentation. The minimum repeat for a punchcard to roll continuously is 36 rows, that fact needs to be considered if punching cards. The repeat shift for the first transfers to happen toward the left is illustrated on the right. 
As initially given, with the lace carriage starting on the left, the first transfer row would be to the right. In many cases, this may not matter, but in this instance, where the knit rows happen after 2 or 4 LC passes respectively, the template offers another instance of the fact that the knitter using it needs to have previous understanding and experience in creating the particular stitch type. This version does not have an accompanying swatch. 
Analyzing the electronic template for interactive knitting: it is correct in marking rows for LC operation from the left with the first transfer row made to the right, matching the above chart. 
Eliminating the rows marked with red would yield a workable punchcard repeat, with loss of the cues for the proper sequence for LC passes.
For good measure, the repeat is also drawn as stitches and produced the punchcard template with a first blank row identical to that generated when using symbols 
Using the pencil tool to draw the transfers differently resulted in a series of error alerts, so not an option.
When manuals are chosen in any module, there is an option offered to download the associated pdf 
by clicking on the arrow key 
Update: 
The lace module is an extremely attractive solution for speeding up the lace design process whether from published charts or DIY. The left mouse button is used to draw as usual, but the right mouse button is used when drawing shared transfers in fine lace on Brother, or simple lace in Studio km.
The designer may enter patterns on this view as well, but I prefer to work with symbols
It is best to begin testing with a small repeat when exploring new techniques, find his format easier to use than drawing on “stitches”. There are several options for the canvas ground color, the default is in blue. As a first step, saved as an stp, Dak opened my saved file as pictured in this view. 
DAK row numbers do not refer to design rows, they reference row counts as would be seen in any row counter registering carriage passes
If a symbol is missing from the drawing, the program alerts the knitter to the error. Here there are no eyelets represented. 
There was no warning for the error in the last row of the test stp, where in the last row two stitches were being moved in opposite directions on the same row. If the content is considered accurate, this window will appear, the safe button will be highlighted, click OK 
wrong side facing is chosen for the purl side view. 
Stitch pattern print previews, using default settings for layout:
This stp pattern was also created using the pencil tool in combination with symbols. In the print preview, there were 2 errors in the Dak printouts, the three blank rows rather than 2 in the outlined section between transfers, and transfers in 2 different directions occurring on the same row with the same carriage pass. I have no way to test whether the same issue would occur in interactive knitting using my own stp file. My repeat, drawn in Numbers on the right, is numbered in design rows. 
choices can also be made on how to represent stitch units If the plan is to create a punchcard template and the repeat is too wide, an error message appears 
Paper size measurements in page set up other than US letter
other associated menu choices 
It is possible to save the template as a bmp of the full image. The size of the file is shown to the right of the pixel count number settings for the clipboard or bmp file, which will vary in proportion to the stitch and row count. Click on the floppy disk icon to save. 
Regrouping after a review of my pencil tool repeat by Softbyte support: the original stp has an error in it on row 11 where yours truly had eyelets being created by having the same stitches moved in opposite directions in the same row. It is interesting that I was able to save the stp without receiving an error message as seen in this instance below when the pattern was being redrawn with transfer symbols on the wrong row, 
As an additional lace template test, I repeated the process on a portion of an stp file shared generously shared by a DAK FB group knitter along with photos of a completed, lovely lace sweater using it. The results are shown sideways because of the repeat length. The 950i template places four rows at the end of each lace sequence, while as seen in the published repeat of a different lace beside it, there should only be 2. The carriage passes made by the KC in traditional lace knitting though they advance the row counter, do not advance the pattern unless it is selecting needles as well, ie in trims that combine lace with the slip stitch setting. Exceptions to the 2 blank rows rule occur when the lace shape reverses direction such as in zig-zags, or when plain knit or pattern rows are planned deliberately to mix and interact with the lace design. 
Please see the previous 
The electronic preview continues to have a series of 4 blank rows between transfer segments. The punchcard template has 2 blank rows between each transfer segment and matches the published pattern with a 3-row exception toward the top of the card. The renderings below begin with the DAK punchcard template on the left with its confused numbering, the extra empty row at the bottom of the repeat was eliminated. The overall repeat is mirrored. It is followed by the published pattern associated with the chart, pixels are then marked for left and right transfers, followed by my amended final repeat, which when knit on the 930 required mirroring. 
Lace tool use instructions begin on page 299 of the third module user manual, Stitch designer. From the manual: when the Lace tool is clicked, lace patterns can be created by using the LMB or RMB to click and hold on the stitch cell where the eyelet needs to be, after which the mouse can be dragged in the required transfer direction and let go on the stitch that needs the corresponding decrease. Intermediate transfer stitches will be added automatically where appropriate. If the button is clicked and the stitch pattern has a method that is incompatible with lace, the warning that is shown on the right will be displayed. The Wrong side facing texture is probably the most natural choice because this is generally considered the normal method of knitting on Japanese knitting machines. Sections of Lace and Fair Isle may be used in the same stitch pattern and either Fair Isle or Wrong side facing texture are good choices when working with lace patterns.
The associated template preview for the punchcard nearly matched the one that was obtained with the pencil tool chart, but had some differences: the previous image was mirrored although no dak settings were changed. As in all punchcard template numbering, the knit row numbers are skipped in the sequence on the left, so they will not match design row numbers, and the small flower motif is placed differently 
A wider swatch
When attempting to use this repeat for a continuous one, unless the total number of rows is an even number, the second repeat will reverse the direction of the transfers, resulting in mispatterning and multiple side-by-side empty needles. Changing the total repeat to 48 rows by adding another blank row places all transfers properly. The 12X48 png
Adding extra knit rows at the top of the repeat ie. 6 or 8 may make the alignment of the 2 shapes to each other more pleasant.
A half drop repeat is also possible. To achieve this test of a repeat drawn in a paint program, I knit 2 rows after the last “flower” eyelet and had to flip the repeat horizontally before continuing for the top half of the repeat, producing a very different look. 
There is a transfer error in the knit swatch on the right where I “repaired” a dropped stitch. Edits would be needed if one is determined to make this pattern automated as a continuous design.
my edit in a spreadsheet, the yellow cells mark rows missing in order to get the lace carriage back to the left side before the next pair of all knit rows. 
opened in ArahPaint, and drawn in brick repeat, shifting the top by 6 cells. The green lines mark the original single blank rows followed by the pairs of added blank rows with no markings, the needed corrections 
the Arah image was saved as a png, knit on my 930 using img2 track, and mirroring
The proof of concept swatch for the now fully automated pattern 
The appearance of the chart or template changes if 2 empty rows are added to represent the KC passes. It may help one understand what is happening but in Brother machines, 2 of the 4 blank rows here would need to be eliminated for the pattern to knit properly. 
Making distinctions in the programming for the repeat depends on its use. If one is using DAK for interactive knitting, by necessity those extra rows are needed to allow for the view onscreen of the rows involved in the plain knitting with the knit carriage. I would assume knitters are instructed to set the knit carriage to KCI or KCII, each carriage will advance the knitting for a row with each pass, extension rails are a necessity since each carriage needs to engage the belt for patterning. Using the same repeat for drawing on a mylar sheet or for download outside the DAK environment the greyed-out 2 extra rows can be eliminated by marking squares or entering pixels and punching holes (depending on repeat width), and the remaining repeat should work.
A Studio repeat adjusted for use on Brother also illustrates that the number of knit rows is only two, the LC passes can vary in number between knit rows. Here LC passes are marked with outlines around pertinent row numbers on the right 
These samples are from Brother punchcard volume 4:
multiple rows of knitting (8) marked aside a single pair of blank rows 
a pattern published on a full Brother mylar sheet 
this is from a studio mylar, the same holds true in terms of the number of empty rows between transfers, 
The LC can move only one needle at a time, so when multiple needles need to move to place the eyelets properly, the options are to use a hand tool to perform the moves or to develop a pattern with multiple transfers in each segment of the final repeat. The full repeats are often very long.
There is a handy option in Dak when thumbnails is chosen from the image menu, one can browse through saved folders containing compatible file-formats including the images in those Brother magazine downloads. The small preview will identify the specific file size. When you left-click on your choice, it will appear enlarged at the bottom left of the view window, it has been moved from its corner in my screengrab, 
left-click OK on the enlarged image, it will open in the program window. Minimize the size until no further reduction is allowed by using the magnifying glass or the scroll function in the mouse. This is a different operation from scaling the original to a different size. The save-as option for the image offered at that point are:
For choices emulating export in other paint programs, right-click on the image, choose copy, open a paint program (Arahpaint is my favorite at this moment), and from its image it menu choose paste. 
Using Arah’s color exchange, the image may then be converted to black and white for 2-color work and is saved in a format usable with other software and in other machines. 
but if the image needs to then be reduced to BW, Arah is the easier and predictable tool to use.
It is useful to establish working history using the same design motif. In the first image, left-click on red, the from color, right-click on white, the to color, click on the double arrow to make and apply the change
The print dialogue allows for saving patterns as bmps. 
choices may then be made about file name and the location for the save, 
If there are no “short” needles in the image being processed as in the last screengrab above, there will be an error message onscreen, pointing out problems in the numbers of colors present in rows ie more than 2 for FI. This is fixed by clicking on either the “needles” of one of the two active colors in the yarn palette to make one color the ground, the other the contrast. The results from this process for printable bmp files are shown below, not for a bmp that may be used to knit the pattern on an electronic machine using a different download method. Here the resulting stitch pattern picture is shown in color reverse as well. 
At this time I am continuing to knit on my machines with punchcards and using Ayab, or img2track on my electronics, have no immediate plans to change that, hence my interest in using DAK software features while keeping in mind the possibility of using the final repeats on other machine models.
The information available to me as I began this post:
When exploring design potential in any paint program, it is best, to begin with, to use a small repeat that can be clearly identified when tiled in various configurations, resized, and pixel edited. If drawing is with the goal to produce a BW bitmapped image for download of 2-color patterns, drawings can happen in those colors to start with. If color separations are planned in the development of the design, then 2 color images including black may be preferable.
To work on the image, magnification will be required. This may be achieved several on the Mac, one is to click repeatedly on the magnifying lens icon in the toolbox, and the other is to press any number from 0 to 9 on the keyboard, and the zoom will instantly change for 1 at 100%, to 6 for 600%, to 0 for 1000. The latter is minimal for building repeats on a viewable grid, the magnifying lens may be used to reach a comfortable starting view. The zoom level for both increases and decreases may be changed during drawing operations as well.
and the program may be used in full-screen mode on your device by making the very last selection in the View menu. 
In addition to the image grid, like Gimp, ArahPaint 6 also allows for positioning aids: guides. They are horizontal or vertical lines that are temporarily displayed on an image. To create a guide, double-click on the dark blue arrow displayed on one of the rulers in the main window. The guide is then displayed as a dashed line following the pointer. To move a guide after it has been created, hover a mouse pointer over the blue arrow and click and drag it to remove the guide to a new location. To delete a guide, double-click on the arrow. After a guide is created, another triangle in a different shade of blue appears below it. Use that to create the next guide, repeat as often as wanted both horizontally and vertically. To remove all guides choose View, Remove Guides. 
One use for the lines can be to mark plain knit rows between transfer markings in lace punchcards as illustrated in this Gimp image 
The foreground (upper square) and background color (lower square) are used in drawing operations. They are numbered 1 and 0, not to be confused with the same numbers assigned to colors in the working palette. The starting palette may be altered to include black. Double-click on the foreground color at the top, the #1, not in the space below the palette icon. A color selection window will appear, choose, and click OK. This change is lost if one quits the program. 
If satisfied with the drawn repeat, use the selection tool to isolate the final motif. 
Pillar repeat also using offset in pixels 
Other offset options through the use of fractions
Playing with mirroring positions, producing a minimum 2 by 2 repeat, 
the result looks akin to the pillar repeat drawing above, but tiling again to check for alignment may yield surprises that can be viewed as design features or errors, 
Repeats may be built in a more controlled manner using the image/duplicate X menu, 
a half drop was added 
and the repeat was tiled to test alignment 
The duplicate tool enables the repeat of an image or part of an image in a fast way. All duplicate tools with the exception of Mirror X-1 and Diamond work similarly to the drawing in repeat tool if the new picture option is enabled. The mirror X-1 works the same as the normal mirror, except the last pixel of the image is omitted from the image 
Eliminating those double pixels can be achieved by cropping. The first mirror is for Y-1, the cropped image is tested for tiling by drawing in repeat 
Drawing lines: use the straight-line icon button to activate the tool, select the line thickness by selecting a number of pixels to be used then move the mouse pointer to a line starting point on the canvas and press the left side of the mouse, dragging it until the line is of the desired length and angle. When the line is at that desired length release the mouse.
The thick lines option works only at line width 1, which will keep the single pixels connected 
If you double-click on the line icon, the Straight-line icon is activated. Now you can draw horizontal, vertical, or diagonal lines. If you move a mouse horizontally—it doesn’t need to be perfectly straight, the drawn line is horizontal. If the angle between a line and the horizontal axis exceeds the angle of 23 degrees, the drawn line will be diagonal at 45 degrees. If you move the mouse toward the vertical axis, the line will be drawn as a vertical line.
The same process, using an 8X8 repeat drawn in repeat X3 in width to 24 stitches and X5 to 40 rows in height meeting the punchcard minimum height 
Finding the repeat first on the complete resulting new image on left and testing its tiling, followed by finding the repeat again, cropping to the selection, and tiling that as well on the right 
If the goal is to knit a scarf, 72 stitches wide, crop either repeat to a chosen 72 stitches in width, tile in length in either program to visually check alignment. If knitting in DBJ for approximately 1200 rows is the goal, one may obtain a visualization of the results ie for 1296 consecutive rows. 
A black pixel border could be added to the 72 stitches by copying and pasting the image on a larger canvas that will accommodate that border, or the border may be added by filling in pixels vertically to the edges of the original. Some repeats to play with: the 120 X 96 png 
The bottom half, 120 X 48, isolated in Gimp, 
tiled in length X4 to get a sense of some of the possible differences I c
I can see the process becoming addictive once a single personally pleasing starting repeat is developed, and its, in turn, becoming a possible source for collections of designs. 
October 2021: I have recently purchased both a PC and DAK software. At the moment I am not planning the purchase of any cables, the initial patterns 
Create a new picture in the same dimensions, fill in the proper cells
The resulting punchcard image 
The color exchange was easy and straightforward with self-drawn images in the opening palette when creating new documents in Gimp. It failed when working on a segment of published patterns. The Arah manual helped me find the solution. Converting the images from true color mode to color palette mode: the original image and its palette, this is not a “correct” working repeat, 
Converting for use with an expanded palette
To change the color of the foreground, double click on it, choose black from the upper left corner of the colors window, the image and its foreground color will change accordingly. 
The successful exchanges 
This repeat would work fine with a reduction to 3 colors, but the proof of concept uses a reduction to 4 colors for both repeats. The two shades of green will need to be exchanged separately, each shade is processed using the sliders on the far right, also note the crosshair. 
With added experience, I discovered part of the problem is that after restarts or working on multiple images, the interpolation setting changes randomly to cubic, and issue are resolved if the setting is changed to none again. 
The Arah scaling appears to be quicker and far more accurate also when used on some published images that would require a lot of clean-up after resizing in Gimp. That said, when working with very large images Gimp offers the opportunity for controlled scaling to any size, keeping the image aspect ratio or not. This reference is described in translation as a pattern design course for Silver Reed knitting machines. 
The publication offers many large-scale repeats that are suitable for punch lace, but also for what translates to “braided patterns” which when studied may be intended for fair-isle with enormous floats or for DBJ. No stitch and row counts are given, the goal is to match the manual 54X56 stitch and row count.
In Gimp, reducing colors: A 
Use scale image to desired dimensions, checking first that values are a full multiple of the expected final repeat pixel count. If not, scale first to a full multiple of each value with aspect ratio off (broken chain link), then scale again with aspect ratio on (intact chain link), edit with a superimposed grid, cleaning up the repeat: C. 
single click on the yellow above to place it in this selection, double click on it 
use sliders again to achieve the white, click OK
ArahPaint will also scale larger images in pixel units. Resizing may be achieved through the use of the image menu Resize option, 
I found the final Arah scaling to be less accurate and requiring more cleanup than the repeat obtained using both programs 
Planning a repeat suitable for a punchcard, the uncropped repeat F is opened in Gimp, and pattern fill is used in white areas to ready the file for tuck knitting. The image is then map tiled to check alignment once more, and if satisfactory, it can be saved, ready to be knit 
With experience, one can quickly imagine ways to clear errors and alter images. Electronic machines free us from repeat width constraints. Widening the zag repeat to 48 stitches, working in Arah, check vertical alignments first, 
Pattern fill may be accomplished in ArahPaint using brushes made from selection and then enabling those brushes with bucket fill. This functionality using multiple brushes to replace colors in the original is shown in this video: 
Working on a possible tuck repeat using only Arah Paint: draw and save the image you wish to superimpose on the ground. I chose to use the color red for visibility. Draw a new image, keeping magnification constant, ie using 0 for 1000 X. Draw a repeat unit for the brush you wish to use, choose repeat from the View menu, click on the stamp icon shown outlined in red, and the available brush will appear immediately below it. 
Lots of knitters appear to be interested in large, nonrepetitive images. Depending on the machine used and its memory, the repeat may need to be split horizontally or vertically. Before electronic machines, many art-to-wear pieces were created by knitting repeats broken down horizontally into the punchcard widths, completing the height of each panel and then joining the strips together. Nowadays there are online tools for many tasks including dividing large images. For DIY, in the first instance, Arahpaint is used to split the “large” file in half horizontally, the resulting image saved. The action happens from left to right, so to achieve the split for the second half, the full-size original is flipped horizontally, split, and flipped again. Followers of my blog have seen the images of my friend Rocco recurring intermittently over the years. Dividing the image horizontally 
The same may be done vertically in a matter of seconds beginning with Image, Halve Y, and then using the mirroring tool 
Color separations: the critical difference in the use of the Arah rectangle tool from that in Gimp is that it cannot be used for sequential selections of pairs of rows in color separations such as those for DBJ or mosaics. In those instances, the Arah image, scaled to the appropriate height may be saved, then opened, and processed in Gimp. For DBJ with each color in each design row knitting twice, design the shape and scale in length in Arah, save and open in Gimp for the separation, see post on working with 
Mosaics: draw the desired repeat in Arah, double it in height, save the image, open in Gimp and proceed with mosaic color separation 
The plan is to create a repeat which may be knit using color changes every 2 rows. Each design row knits each color twice, so the standard built-in KRC separation is not a consideration, though the same cam settings may be used in those fabrics as well.
End needle selection is canceled, the first and last needles are in work on each side on the ribber knitting every row, the first preselection row is from right to left, cam buttons are set after the left side is reached. Knitting in these samples began with the blue yarn in the number 2 position in the color changer. The ribber remains set for knitting in both directions throughout, the images on the right do not reflect the amount of surface 3D textures.
Lock settings are easier to achieve on the Passap than switching out cam buttons in Brother machines. This was knit using 4 carriages. Color one knits with the main bed set to tuck both ways, color two knits with the main bed set to slip both ways. The slip stitch reduces the width of the fabric considerably 
Here each color alternately tucks and slips. The choice of cam buttons matters, tucking first from left to right, slipping from right to left, with cam buttons set COL after the first preselection row 
This last cam setting appears to my eye to produce a texture “close enough” to the inspiration fabric. Attempting to add more colors: the repeat, D, is still 18 X 88 but is now shifted slightly. 
The existing repeat may be reduced further to 18 X 64, eliminating some of those extra rows in the center of the chevron shape 
Whether or not the design is intended to retain chevron shapes in alternating textures, actions may be plotted pre knitting in any way that visually makes sense to the person designing the pattern and tools available to them. 
Reversing the png so that the more textured stitches will begin with the color in yarn position 1
Using either repeat, color changes now occur after every 32 rows knit. Another color change location clue is in the needle selection change above and immediately following the red border in the chart on the left. 
Adding colors can be planned cautiously or allowed to happen randomly depending on the preferences of the designer and end-use. Ribber fabric designs are not visible until several inches have been knit, too late to catch color sequence errors. Some machines allow for memo placements or sounds to help track color changes, but only within the initially programmed repeats. A quick spreadsheet can provide customizable checkboxes or added information. For an attempt to retain chevron shapes in different textures: 
A PDF including row numbers and space for notations 
The test swatch and observations: patterning was begun with color 2, yellow.
Continuing on a 24 stitch repeat, the original design may be rendered at double height and separated once more, doubling the separation height to 96 rows 
There are days when either or both machine and knitter need a break. At the start of the first swatch, the cam buttons were not set, resulting in plain knit stripes. At its top, the purple did not get picked up properly from the color changer, and the knitting of course fell off the machine. On a second try, the same issue happened again with the purple yarn. Multiple incidences of such events were fondly nicknamed “dropitis” by my students. The test is on 24 stitches, the width of a single repeat, the triangles are much more balanced in size, this knitter is putting this pattern to rest. 
Another even more complex inspiration from a sweater attributed to Falke, Spring 20 collection, using similar stitch structures, but in addition, also transferring stitches between beds exposing a purl striped ground.
For some reason, I found the commands erratic when working on the translated version of the site, and fared much better in the original language publication.
Screengrab the final image surrounded by extra white cells, and open it in GIMP.
Getting a preview of how a finished garment might appear, here the tiled version is 192 pixels in width and one may glean some idea as to whether that repeat should ever really be used in a sweater or even a blanket. Further image scaling or cropping can happen based on the knit gauge. 
A very quick rendering imagining pattern and color placements using a simple sweater outline 
Collections of every other needle repeats for processing with a similar approach may be found in these volumes, available for free download
Both volumes include accompanying swatch illustrations.
For a better, printed match size, after capturing the image from the PDF for a single page outside image edges, opening it in Gimp, and cropping it to content, it is then possible to scale the results to measurements of a factory punchcard equal in width and adjusted for the number of rows in the image. My card required print measurements were 14.1cm by 26.1. Scaling executed with an aspect ratio that is too long. 
breaking the chain-link, removing size constraints 
The results with the selection of even rows simply shift the result up a row 
Test in your version of the program to see whether releasing the shift key prior to making edits changes them. Either way, being consistent in the choice makes for less confusing results. Experimentation takes a matter of seconds.
using the rectangle tool, either odd or even rows may be chosen, remaining consistent for the height of the repeat in a scale to suit the end fabric goal. Here the original file is lengthened X2
working with the original file lengthened x4. The selections can happen on every row or every other, whether singly or in pairs. Note the difference between making the first selection on the first pair of rows or the second. 
2021: 
single click on the filing cabinet icon on the right, 
double click on the patterns folder, and its own window will appear, 
and the new folder will be added within the brushes one 
For future use, any saved brush may be dragged and dropped into the named personal pattern folder icon, or into the folder after it has been expanded or opened in its own window. My opened brush folder 
When exporting self-drawn brushes, the option is offered for adding spacing surrounding the shape, here a 10% addition was chosen 
To save personal patterns, instead of choosing the file cabinet icon in preferences, one may choose the folder icon, following a similar series of steps to those above, including verifying the contents of the newly created folder 
Use Windows, Dockable Dialogues, choose Pattern. The patterns will show on the right
Click on the paint bucket, then on the pattern you wish to use on right, hover over the canvas with the paint tool, click on it and the image will fill in the chosen pattern.
Foreground and Background colors: in RGB Mode, click on the foreground color to select a new color for the grid, click OK 
This command is found in the image menubar through 
You can create as many guides as you like, positioned wherever you like.
Built-in or custom brushes may be superimposed on a bucket-filled ground. Create an image in the desired width and height, here 24 X 24, and magnify at least X 800 for a grid view.
The color exchange window will appear. Here the white “from color” is left undisturbed. Select the dropper next to the “to color”, then click on the image on the color you wish to change, a palette window will appear. Make your choice, the color exchange window will now have substituted the chosen color for black, click OK, and white design areas are now changed to the chosen blue globally. 
The process may then be repeated with the second color if desired. The color exchange window will show white as the default “from color”. Click on the white bar, choose black from the palette window or use the dropper to select black from the image. The from color will then appear as black. Repeat selection with the dropper from the right of the “to color” bar on any black pixels in the image, choose the color from the palette window to replace it, and the color exchange window will display the new “to color”. Click OK, and job done. 
The process may be repeated multiple times on the same design or used on large-scale ones, giving one some idea as to whether or not to really commit to the estimated colors. 
I recently had reason to review old PC files from my Passap knitting days and came across several cut files that when converted to png format appeared in colors rather than black and white, leading me to experiment with color exchange again. The image for the first experiment is part of a crib blanket by Cheryl Giles
It is possible to colorize images originally drawn in black and white. The color exchange options will remain fixed throughout the process. The image may be worked on continuously and exported when color exchanges are completed, or saved and imported again after each step. The color exchange here happens consistently on the chosen background color, changing that quickly becomes familiar and easy. There are times that the repeat being processed will turn black onscreen, trust in the process and continue.
Developing custom palettes in order to visualize different colorways while using the same repeat:
this window will open with selections for possible palette choices 
click on your choice, then click on the palette icon, and your color choices will appear, click on the white, to create a new background color. 
My success with series of other images in using color exchange has been spotty. Online forums reveal this is a recurrent issue with no clear solutions. Suggestions include stipulating that the cause may be the version of Mac OS in use. Color reductions using 
The image itself may be scaled concurrently to tweak grid border alignments. The final grid size below is 18X18, the image size is shown after scaling from a width of 277 pixels (with a broken link at that time) to a final 270 pixels in width 
The screengrab of the above center, with a superimposed new grid; note the image, in this case, was also offset for better placement, a 3-pixel pencil was used to isolate the border of the possible smallest repeat 
Translating the colored image to BW indexed may take several steps and some clean-up if only Gimp is used to process it. With the colored large-scale isolated repeat, the image is opened in Gimp. The Threshold tool transforms the current layer or the selection into a black-and-white image, where white pixels represent the pixels of the image whose Value is in the threshold range, and black pixels represent pixels with Value out of the threshold range. It may be activated from the pull-down colors menu or from the toolbox. 
Color separations: there are occasions where very small repeats need to be scaled in height only for color separations. I have found such scaling to be inaccurate using the option, such as here, both of the small, single repeat, and in scaling its tiled version. The triangle motif was used in many of my early posts on color separations for DBJ and its backing options. 
The appearance of the final repeat when color is reversed 
Another comparison of the 2 options for altering every other pair of rows in the specific color separation for a mosaic repeat. There is less filling in of cells with a different color, but in large files especially, I feel the result would become far more visually confusing to track. 
Working with potential knit repeats the scale is reduced further. Magnification is useful for the evaluation of repeats. The smallest repeat segments for use on electronic machines may be isolated. The filter, map, and tile option easily verify how the repeats line up overall. Cropping a 24-stitch width and tiling that also visualizes the suitability of the repeat for use on punchcards with the 24-stitch limitation. Grid view helps identify any need for “clean up”.
and a type of symmetry and accompanying settings, click on pencil tool, the motif will appear as on the above right, paste the image on the new canvas, undo and repeat setting adjustments until satisfied with the distribution of motifs.
The 24X50 repeat: 
To decrease crowding, using the original image, the new canvas is now 40X60, with the shift decreased from 12 to 8 pixels. The result did not tile properly when mapped, using magnification 800X with a viewed grid the final repeat, 29X60 was isolated 
Being more deliberate with the math leads to a full, successful repeat 
Using that small triangular 8X8 repeat
Again, preemptive math will yield images that avoid further processing. It is up to the user to recognize any problems, the repeat here needs to and can be isolated correctly from the file on the left, it is actually only 16 rows high. Here the adjusted repeat is created on a 24X16 canvas with the same symmetry settings, and filter/mapped/tiled 
The above repeat was cropped and adjusted to 16 stitch width and 8 row height, the file saved, and the process repeated 
Using symmetry once more, remember to adjust the pencil size. 
I was unable to use color exchange successfully on the above images, but with the saved 2 colors indexed red and white repeat both img2track and ayab appeared to load the repeat successfully. 
The map color exchange was successful using the steps described at the top of the post when beginning with the repeat drawn in a black and white version. 
Nearly all my previous dbj pieces have been knit on a Passap E6000. The 930 experience for such repeats is new to me. With some help from Tanya Cunnigham in reviewing the steps required when using img2track, I returned to cellular automata repeat saved years ago.
That provided an opportunity to decide I preferred the reverse color placement as well as wanting a thicker ply for the white, resulting in twice the fun with 2 colors, and another scrapped sample 
I was able to achieve a reasonable repair on the knit side, but the birdseye pattern on the reverse is a bit scrambled. 
There is also potential for exchanging colors to get a sense of how the pattern might appear in different colorways