Hayaki Saito

When canceling control sequences such as SIXEL, I recommend outputting the control character `0x18 (CAN)` or `0x1A (SUB)`. Although few terminals implement this behavior as described in the DEC manuals,...

> Also note that none of these controls will do anything to prevent incomplete frames from being displayed on a real terminal (or a serious emulator), because sixel images are...

@j4james > Are you using 180 dpi by any chance? Yes, I should have read the manual more carefully -- 256 colors aren’t available in the default 180 dpi mode....

> As for the LJ250 “256-color” mode, it’s essentially a halftone: It sprays the three primaries to form the 2^3 = 8 base colors on a 180 dpi grid, then...

I tried printing at 180dpi 8color. ``` $ converters/img2sixel images/snake.jpg -m images/map8.six -R | tee snake-map8-testprint.six.txt > /dev/cu.usbserial-2 ``` [snake-map8-testprint.six.txt](https://github.com/user-attachments/files/22703869/snake-map8-testprint.six.txt)

The 8 colors in `images/map8.six` are likely suboptimal; the inter-color distances aren’t ideal for dithering, so we probably need to derive a new set of 8 colors from a color...

@j4james Thank you. I’m not a color expert, but here’s my current thinking -- there are four color spaces involved: (1) A base space for palette mapping and diffusion To...

I printed the LJ250’s 256-color chart; the red box marks the base 8 colors. I didn’t know about "colorimeters", but chatGPT suggested that’s the proper tool -- since I don’t...

@Crispy-fried-chicken Thank you for the report. For regression testing, may we add the PoC file you provided to the repository?

@Crispy-fried-chicken I can’t reproduce. The argument order in your example looks off: ``` -k -g -g -d jajuni -c 100x100+10+5 a_dither -h 60 -o -s average -e -f lum -d...