libmfimage

Library for reading / writing images from multiple file formats in a way suitable for color management and manipulating them.

The main purpose is reading image files, if suitableobeying color space instructions embedded in them in a coprehensible way and indicating if no color space instructions are included, so that the image loaded in memory can now be used in a color managed application.

There are also manipulation routines (flip, rotation, separation, combination, levels & gamma, brightness+contrast, alpha-channel manipulation, compositing obeying alpha-channel) for images available as well as single color value coversion routines for often used color space conversions (icc-profile ↔ icc-profile, icc-profile ↔ L*a*b*, icc-profile ↔ sRGB, RGB ↔ HSV, L*a*b* ↔ LCh).

Writing images is limitted to some formats, at least in the initial version. The best implemented format for writing images to disk is tiff, which by design allows flexible, lossless, compressed and multi-page images - everything one could ask for!

Its design goals are to be as operating system independant as possible, easy to use and maintain, high performance capable. And of course dealing with colors in the "right" way, allowing an ICC workflow to be built ontop of it, giving you all the required information from the image file you need for that at a small footprint.

The original purpose of this library was to be the backend for image reading/writing/manipulation of the mfscan sane frontend.

Features:

• reading/writing images from multiple file formats, inlcuding GIF, TIF, JPEG, JP2, PNG, BMP, PCX, TGA.
• When suitable, assigning color spaces to the image (e.g. PNG sRGB, JP2 sRGB, PNG cHRM/gAMA, embedded ICC profiles)
• Support to convert color spaces based on littleCms
• Using wide-spread standard and de-facto standard image format libraries like GIFLIB, libtiff-4, libjpeg-turbo, openJpeg, libpng.
• Wide range support for subformats (for example CMYK JPEG, TIF Compressions, ...)

Internal image handling

Color Model	channel depth	alpha
RGB	8, 16, float	✅
GRAY	8, 16, float	✅
CMYK	8, 16, float	✅
L*a*b*	float	✅

Supported Image File formats:

File Format	Read	Write
TIFF	✅	✅
JPEG	✅	📋
JP2	✅	📋
PNG	✅	📋
BMP	✅	✅
PCX	✅	◽
TGA	✅	◽
PSD	📋	◽
PDF	📋	📋
📋 = planned

Sub-Formats supported for reading

###TIFF

Color Model	BitDepth	AlphaChannel
Monochrome	1, 4, 8, 16	✅
RGB	8, 16	✅
RGB Palette	4, 8	✅
CMYK	8, 16	✅
CIELab*	📋	📋

Compression: Uncompressed, RLE, FaxG3, FaxG4, LZW, JPEG, Deflate, Packbits, Thunderscan, LZMA2 Organisation: Continguos, Planar / Stripes, Tiles Multipage: ✅

###JPEG

Color Model	BitDepth	AlphaChannel
Todo: Describe

###JPEG2000

Color Model	BitDepth	AlphaChannel
Todo: Describe

###PNG

Color Model	BitDepth	AlphaChannel
Todo: Describe

###BMP

Color Model	BitDepth	AlphaChannel
Todo: Describe

###PCX

Color Model	BitDepth	AlphaChannel
Todo: Describe

###TGA

Color Model	BitDepth	AlphaChannel
Todo: Describe

###TGA

Color Model	BitDepth	AlphaChannel
Todo: Describe

###PDF Embedded JPEG images in PDF pages. Not yet implemented. Todo: Describe deaitls

Language & Operating system:

The library is internally written in C++(11/14), but also comes with an external C-interface to simplify usage from other languages and for Windows dlls.

License

Dual-license: GPLv3, commercial license available on request.