/// <summary>
/// Gets an enumerable array of bytes representing each row of the image.
/// </summary>
/// <param name="image">
/// The <see cref="ImageBuffer"/> for storing and manipulating pixel information.
/// </param>
/// <param name="lookups">
/// The array of <see cref="Color32"/> containing indexed versions of the images colors.
/// </param>
/// <param name="alphaThreshold">
/// The alpha threshold.
/// </param>
/// <param name="paletteHistogram">
/// The palette histogram.
/// </param>
/// <returns>
/// The enumerable list of <see cref="byte"/> representing each pixel.
/// </returns>
private static IEnumerable <byte[]> IndexedPixels(ImageBuffer image, Color32[] lookups, int alphaThreshold, PaletteColorHistory[] paletteHistogram)
{
byte[] lineIndexes = new byte[image.Image.Width];
PaletteLookup lookup = new PaletteLookup(lookups);
// Determine the correct fallback color.
byte fallback = lookups.Length < AlphaMax ? AlphaMin : AlphaMax;
foreach (Color32[] pixelLine in image.PixelLines)
{
int length = pixelLine.Length;
for (int i = 0; i < length; i++)
{
Color32 pixel = pixelLine[i];
byte bestMatch = fallback;
if (pixel.A > alphaThreshold)
{
bestMatch = lookup.GetPaletteIndex(pixel);
paletteHistogram[bestMatch].AddPixel(pixel);
}
lineIndexes[i] = bestMatch;
}
yield return(lineIndexes);
}
}
/// <summary>
/// Gets an enumerable array of bytes representing each row of the image.
/// </summary>
/// <param name="image">
/// The <see cref="ImageBuffer"/> for storing and manipulating pixel information.
/// </param>
/// <param name="lookups">
/// The array of <see cref="Color32"/> containing indexed versions of the images colors.
/// </param>
/// <param name="alphaThreshold">
/// The alpha threshold.
/// </param>
/// <param name="paletteHistogram">
/// The palette histogram.
/// </param>
/// <returns>
/// The enumerable list of <see cref="byte"/> representing each pixel.
/// </returns>
private static IEnumerable<byte[]> IndexedPixels(ImageBuffer image, Color32[] lookups, int alphaThreshold, PaletteColorHistory[] paletteHistogram)
{
byte[] lineIndexes = new byte[image.Image.Width];
PaletteLookup lookup = new PaletteLookup(lookups);
// Determine the correct fallback color.
byte fallback = lookups.Length < AlphaMax ? AlphaMin : AlphaMax;
foreach (Color32[] pixelLine in image.PixelLines)
{
int length = pixelLine.Length;
for (int i = 0; i < length; i++)
{
Color32 pixel = pixelLine[i];
byte bestMatch = fallback;
if (pixel.A > alphaThreshold)
{
bestMatch = lookup.GetPaletteIndex(pixel);
paletteHistogram[bestMatch].AddPixel(pixel);
}
lineIndexes[i] = bestMatch;
}
yield return lineIndexes;
}
}
