Color incorrect using image converter result.

Hello Gordon,
I don't know if I found bug, but i've encontered strage behaviour. Converted png image using https://www.espruino.com/Image+Converter
Original image is RedHeart.png [attached]
Result for converted [attached] is

var img = {
  width : 48, height : 48, bpp : 4,
  buffer : require("heatshrink").decompress(atob("xAAbzOZzAKHxILBCxQACBSALFGIotCDBALGBggKGEYgLGBgYiHEYYLIBgQKIEZYXOBZAMBERIjLC5oLKC5YLLABYX/C8CnKABa/LC/p4UOwIXYJCgWCC7BISIwYwTCwgwRFwoXYJCAWGGB4uHGB4WIGBouJGBoWKGBYuLGBYWMGBIuNGBIWOGA4uPGA4WQGAouRGAoWSGAYuTGAYWUC7GJIyoA9A"))
}

Result in IDE emulator and actual device [attached] is BLUE as seen in one of the screenshots. Is it error in https://www.espruino.com/Image+Converter or something else?

My code to display picture is following:

const fontName = "6x8";
  const fontSize = 3;
  g.clear();  // clear screen
  g.reset();  // default draw styles
  g.setFont(fontName, fontSize);
  g.drawImage(img, 48, 125);

3 Attachments

Bangle.js doesn't support 4 bit RGBA - it assumes that all 4 bit images use the Mac palette. You can see what color formats are supported here: https://www.espruino.com/Reference#l_Graphics_drawImage

It really was my issue- incorrect color format. Thak you

Yep - RGBA is there to help with other devices. You could actually still draw the image in RGBA if you supplied your own palette though: http://www.espruino.com/Reference#l_Graphics_drawImage

Just to add - in this sort of case I'd actually recommend you use either black and white 1 bit (or 2 bit if you want a really smooth image). While you end up with a black and white image, you can just use g.setColor("#ff0000") before you draw to make it red (or whatever colour you want)