Formats

Only RGB, YCbCr, and Grayscale color spaces are supported. When reading a YCbCr image, it is converted to RGB on input. CMYK, YCCK, and proprietary color spaces are not supported.

When writing RGB images, ImageTools[Write] uses the YCbCr color space, which is the standard for JFIF formatted JPEG files. When writing grayscale images, the Grayscale color space is used.

JPEG reading and writing support is based on the Independent JPEG Group's "libjpeg", version 6.2. See copyright.

All TIFF images returned by ImageTools[Read] are converted to grayscale, RGB, or RGBA data.

When writing to TIFF files, ImageTools[Write] produces 8-bit per color channel, contiguous plane, LZW compressed, RGB or grayscale files (depending on the image data to be written).

TIFF reading and writing support is based on Silicon Graphics' "libtiff" library, version 3.6.1. See copyright.

When reading 1-bit, 4-bit, or 8-bit color mapped images, ImageTools[Read] returns grayscale data if all the colors in the image's color map are shades of gray, or RGB data otherwise.

Only 8-bit and 24-bit BMP files are supported by ImageTools[Write]. Grayscale data is written in 8-bit color mapped format (where all the colors are shades of gray). RGB data is written in 24-bit true color format.

When reading color mapped images, ImageTools[Read] returns grayscale data if all the colors are shades of gray, or RGB data otherwise. When reading grayscale images with an alpha channel, RGBA data is returned.

When writing a PNG file, ImageTools[Write] produces a 24-bit RGB, 32-bit RGBA, or 8-bit grayscale file depending on the image data being written.