getPixelColor

Retrieve RGB values of any PlacedItem regardless of format by parsing raw binary, all in pure scripting.

By request on the Illustrator forums

Given any image within the Illustrator canvas, like a very ugly 3x3 pixel PNG:

Grab the RGB values of any given pixel, list of pixels, or entire image. Note that coordinates are 0-based and top-down:

getPixelColor(pixels?: number[]|null, options?: <Options>)

All options are optional, with default values being:

{
  // Function called at the very end of execution
  onComplete: null,
  // Function to modify binary data before parsing begins
  onBeforeParse: null,
  // Function to return parsed binary rawdata
  onAfterParse: null,
  BMP: {
    // File location of temporary image
    imagePath: Folder.userData + "/pixelGetColor.BMP",
    // Whether image is automatically deleted after use
    deleteImage: true,
    // File location of temporary action
    actionPath: Folder.userData + "/exportBMP.aia",
    // Whether action is automatically deleted after use
    deleteAction: true,
  },
  // Whether to return as native RGBColor or if false, as JSON
  returnColor: true,
  // Whether to return from parsing containing metadata about file such as width and height
  verbose: false,
  // Whether to remove duplicate colors
  removeDuplicates: true,
  // Whether to, if only one color is found, return the color directly instead of a 1-length array
  flattenResults: true,
}

Examples using above 3x3 PNG:

Reading a single pixel:

getPixelColor([0, 1], {
  // Easily write yourself a log via lifecycle hooks:
  onAfterParse: function (result) {
    alert(result); // [{"r":53,"g":255,"b":29,"a":0}]
    // This function is not included but simple to make:
    writeFile(
      Folder.userData + "/results.json",
      JSON.stringify(result) // JSON is also not included, just for demonstration
    );
  },
});

Reading multiple pixels, with additional metadata:

getPixelColor(
  [
    [0, 1],
    [1, 1],
  ],
  {
    verbose: true,
    onAfterParse: function (result) {
      writeFile(
        Folder.userData + "/results.json",
        JSON.stringify(result) // JSON is also not included, just for demonstration
      );
    },
  }
);

{
  "width": 3,
  "height": 3,
  "bpp": 4,
  "bitDepth": 32,
  "pixelData": [
    { "r": 53, "g": 255, "b": 29, "a": 0 },
    { "r": 29, "g": 203, "b": 255, "a": 0 }
  ]
}

Reading every pixel of the canvas:

getPixelColor(null, {
  onAfterParse: function (result) {
    writeFile(Folder.userData + "/results.json", JSON.stringify(result));
  },
});

[
  { "r": 246, "g": 40, "b": 255, "a": 0, "x": 0, "y": 0 },
  { "r": 255, "g": 184, "b": 44, "a": 0, "x": 1, "y": 0 },
  { "r": 100, "g": 100, "b": 100, "a": 0, "x": 2, "y": 0 },
  { "r": 53, "g": 255, "b": 29, "a": 0, "x": 0, "y": 1 },
  { "r": 29, "g": 203, "b": 255, "a": 0, "x": 1, "y": 1 },
  { "r": 251, "g": 127, "b": 127, "a": 0, "x": 2, "y": 1 },
  { "r": 255, "g": 255, "b": 255, "a": 0, "x": 0, "y": 2 },
  { "r": 0, "g": 0, "b": 0, "a": 0, "x": 1, "y": 2 },
  { "r": 0, "g": 0, "b": 255, "a": 0, "x": 2, "y": 2 }
]

Note the Y values here aren't correct and are inverted. This is due to BMP encoding being linear from left > right and bottom > top. Will fix this soon but running out of time on a weekday.

Getting every color of the canvas:

getPixelColor(null, {
  /* 
    Since returnColor is true by default, onComplete lifecycle acts similar to onAfterParse with the 
    exception that it processes the results (like removing duplicates and transforming to vanilla colors)
  */
  onComplete: function (result) {
    writeFile(Folder.userData + "/results.json", JSON.stringify(result));
  },
});

[
  [RGBColor],
  [RGBColor],
  [RGBColor],
  [RGBColor],
  [RGBColor],
  [RGBColor],
  [RGBColor],
  [RGBColor],
  [RGBColor],
];