The type of metadata, this is typically the name of the chunk from which is originates.
The number of significant bits for each channel. The format of this property depends on the IPngDetails.colorType of the image:
0 (Greyscale): number2 (Truecolor): [number, number, number]3 (Indexed): [number, number, number]4 (Greyscale and alpha): [number, number]6 (Truecolor and alpha): [number, number, number, number]
A metadata entry that defines a bit depth less than or equal to the image's bit depth which allows potentially storing bit depths not equal to 1, 2, 4, 8 or 16 within pngs. Since the assembled data is output as a 32-bit image or 64-bit image, this is only useful in the library for handling non-standard bit depths of 9 to 15.