An image codestream's header: its size, components and precision as the codestream declares them.
public ImageHeader(int Width, int Height, int Components, int BitsPerComponent)
The number of samples in each row.
The number of rows.
The number of colour components (without an opacity channel).
The precision of the components; the greatest when they differ.
ISO 32000-2 §7.4.9 and §8.9.2. Returned by TryReadHeader(ReadOnlySpan<Byte>, ImageFilterContext, out ImageHeader).