Software – Page 14 – alessandrina.com

Color reduction/conversions, Mac Os

A recent forum post brought up the question that rises periodically on how to reduce colors in photographs, scans, etc. so as to be able to in turn use the image in a low-resolution medium such as knit. There are very many ways to achieve this. The post had specifically asked for low cost or free alternatives using Mac software, so I began playing, and compiled the following document detailing some of my processes, addressing large scale, non-repetitive images in Color reductions for knitting. The document samples were simple, straightforward conversions, with no further “tweaking”.

Mac Os: iPhoto, Preview, further software downloads:

Free: img2trak, HyperDither, XnConvert

99 cents One bit Camera
an option for Mac users, Bitcam

Free to try, $39.95 to buy GraphicConverter, the developer site
diffusion, halftone, pattern, custom A tutorial for owners of Photoshop diffusion, halftone, pattern, custom With thanks to my test subjects: Rocco One bit camera and my sofa fabric

An online service that will do the conversion for you: Knitpro, and a free service GitHub May 2019: ditherlicious

A later post on the topic, showing the many faces of Rocco

Knit QR codes 1, repeats from BW images

A video on this topic. I work using Mac OS 10.10 at the moment. When I first wrote on this topic, I downloaded a then free converter The app, Aztec Code Generator, is now no longer free (11/2015) but costs $ 1.99 to purchase. There is a still free, online QR generator

my beginning code

the original image size was reduced to 60 pixels square, and in turn to 40 pixels square respectively, then magnified to 600 times for superimposing the single stitch grid as described in the video; screen-captured image saves are needed for saving gridded images

the 60 stitch repeat

the 40 stitch repeat

using the Aztec code generator to control output size

saved

X1,000, cropped and gridded

not all units are created equal: areas numbered indicate where some of the horizontal units are 5 wide rather than as most 4, and closer inspection will reveal the same for some vertical units. Reconfiguring the grid ie to 4X4 pixels would be an alternative way to “resize” the image, but fails because of the disparities when the unit is applied overall

trying the same process on this BW jpeg, the resulting repeats require further cleanup and editing along edges of shapes

using GIMP: 40 stitch repeat, no additional scaling, converted to 1bit BW, could use a bit of clean up, I prefer to work with a black grid

24 stitch

as an afterthought: results using img2track to pixelate the same image before gridding

please note these scroll graphs are not accurate working repeats to be knit as they are

it is always a good idea to test tiling for any “surprises” before any actual knitting

11/2015_Knitting’ low resolution is reflected in the number of stitches and rows per inch or per repeat. In this instance, Gimp was again used to scale and process the image

Today’s generated image: happy holidays QR code, Aztec code generator, 300 pixels square including white border

color mode converted to 1-bit B&W; 100 stitch repeat

scaling, gridding for 30 stitch repeat

for 24 stitch repeat: note loss of detail as stitch and row counts are reduced

h&h24

and happy holidays via the free, online generator using the generator options to control available output size

The above begs many questions. Upon investigation, it appears there are 18 2D bar code variants, some static, some dynamic. Qrme is a UK site that provides information on trackable QR codes, forums, and more. Their page shows scaled in size codes modules.

HK pattern, software charting.

I have reached the point where decades old (89 and earlier) magazines that got “saved” are now being peeked at, and if not given away, then recycled. There may be some bleed through here from pages I have “saved” once again. Browsing through I found some designs not appropriate for machine knitting for one reason or another, but still creating interesting surfaces and the chance to explore using intwined’s other features. The program will create text from a chart, or chart from typed text with some limitations. One of the latter is a very large cable as seen in the attached document. PDF exports can happen within the program if one is specific in the sequencing of creating its documents. The 1989 pattern had only text for the repeat; I typed it, and had the chart pretty much created for me except for the problem row 5. Here is the resulting Intwined created PDF with some of my comments: cable_diamond. The following is the graph I edited, with my illustration for the execution of row 5

the blue line separates the slip stitch section, which can serve as a border on each side of the cable panels, the red lines the edges of the 12 stitches involved in the cable. The green stitches are put on a cable needle and brought to the front of the work, the next 6 stitches are knit first, then the ones from the cable needle to complete the crossing.

the swatch: knit side

the purl side

…

Hand to machine knitting, symbols 1

One of the critical differences in viewing work as it progresses on the knitting machine is that the “front” view of the fabric unless the work is removed from the needles through a variety of techniques and turned over on the needle bed, is the purl side. Early machine manufacturer punchcard book publications made an effort to help hand knitters make the transition. A chart from brother publishing knit_sym96 illustrates one such effort. Here the middle icon in the how to work column is the stitch formation one would need to achieve on the MK to get the same “look” as the HK samples. Some symbols apply to both types of knitting, some should be mirrored horizontally to make sense, and in the case of the crossing stitches at the top right of the second column, there is a bit of confused identity.

Over the years there has been an interesting transition from handwritten stitch by stitch instructions to the introduction of symbols ranging from homegrown on graph paper, to simple word processing and later software generated ones. Some international differences occurred in published works, and internationally agreed-upon symbols for both knit and crochet eventually evolved. There are many design programs on the market now, I have linked to some in past posts. As knitters have venues for publishing their own repeats and patterns and tools have multiplied, symbols do not always necessarily have the same meaning, and stitch codes are no longer universal.

I have been wanting to find a way other than using excel to build a stitch library usable for machine knitters in an easily accessible program that would do some of the “work” for me. I have experimented with 2 programs. One was knitbird, which I would not recommend for this purpose, the other Intwined Studio which is proving far more flexible and worth the modest investment for me. I work on MacOS10.8, the Intwined version for this OS is beta. There are some small glitches, but this is a tool worth exploring. The option is there to add one’s own symbols to the stitch library. I have begun working on a machine knitting set with icons created in a combination of other programs and Inkscape, the one suggested in the tutorial by the developer. Some charts created with Intwined may be seen in my previous post on sideways pleated skirts. Below is a chart including some MK symbols in my personal library, also using the option to the color background for them in the program itself rather than editing the chart image after the fact.

To download Inkscape: site. The workaround to get the program to work in Mac OS10.8 may be found here.

The combination of color with symbols in published patterns for both hand-knit and crochet is beginning to proliferate. I find the visual color cues help track patterns more easily, have done it in HK in the past, one such example is my chain cable experiment in my January 3rd post.

Some illustrations for lace symbols HK vs MK may be found in my post from February 25, 2012 “back to lace”.

My latest shawl

Still working on lace pieces, sorting out the differences and issues in this knit fabric type. My shawls are one-of-a-kind or limited edition items. The fiber content and finished sizes vary.

This is the repeat as it may appear in a hand-knit lace graph. Not enough symbols in Knitbird, the design was achieved by using the Aire River knitting font, and applying appropriate symbols to an excel grid

border transition detail shot

the shawl

Oh the math! “magic formula”

There are many knitting programs that will perform the necessary calculations, as well as a variety of knit calculators. The diophantine formula is the basis for what is known to some knitters as the “magic formula”. In the early 1980s, Alles Hutchinson authored a small book on the subject. There is a bit of personal leeway in the results, and the formula may be used in calculating even complex shapes with the proviso that one has the patience to break such shapes into series of simpler ones.

There are many online resources for information and calculators to sort out the math, including a triangle calculator. The original website’s offerings are now closed, but the info remains available here
https://web.archive.org/web/20200224005535/http://www.getknitting.com/ak_0603triangle.aspx

Using the gauge to match the previous post of 4S and 6R per inch the calculation for the pie divided into five triangles breaks down into the web calculator result pictured below:

The longhand method for the same calculation follows and also translates to: bring into hold 2 stitches for 4 times, 1 stitch for 80 times. Stitches in shaping are proofed as above: 88 stitches shaped over 84 rows.