Misleading information in bmp format

Complaint
1

so while following bmp format docs i found a misleading information at color palate section. so according to the docs 16, 24. 32 bit bmp image never contain any color Palette or color table. which is not right because i found this image which is a 565 16 bit bmp image containing a color table and also ExtraBitMask.

2

@ovpoddar

In general, BMP images with 16-bit, 24-bit, or 32-bit color depths typically do not contain a color palette (color table). The palette is most commonly associated with BMP images that have lower color depths (like 1-bit, 4-bit, or 8-bit). However, there can be exceptions based on specific encoding methods or variations of the BMP format.

For instance:

  • 16-bit BMPs: They can use different encoding formats like RGB 555 or RGB 565. Some BMPs might contain additional structures, like a color table or extra bitmasks (for transparency or color channel information), even though this is not the default behavior.

  • The RGB 565 variant you mentioned might be using the color table for more precise color mapping or other encoding purposes, though this isn’t the norm for most BMPs.

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