This property determines the precision of the output color
The value is specified in terms of the number of bits used to
represent each channel of color. This can be 1, 8 or 16.
All color spaces support 8 and 16
bits per channel. Only the Gray color space supports 1 bit per
The TIFF output format supports all output precisions. The JP2
(JPEG 2000) and PSD (Photoshop) formats support 8 and 16 bits per
channel. The JPG, GIF, PNG and .BMP. output formats support 8 bit
RGB and 8 bit Gray only.