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 separate for mosaic knitting using only GimpWorking on the black and white indexed repeat, use 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 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 tiled for repeat alignment check, 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. 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 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