At present, in color management technology, the so-called color feature connection space adopts the chromaticity space of CIE1976Lab. Colors on any device can be converted to this space, forming a "universal" description way, and then color matching conversion. In the computer operating system, the task of implementing color matching conversion is completed by the "color matching module", which is of great significance to the reliability of color conversion and color matching.

This requires each set of devices to generate a profile, the color signature file of the device. We know that different devices, materials and processes exhibit different characteristics when it comes to rendering and transmitting color. In color management, the color presented on one device is presented on another device in high fidelity, which requires us to understand the characteristics of color presented on various devices. Since a device-independent color space, CIE1976Lab chromaticity space, has been selected, the color characteristics of the device are represented by the relationship between the description value of the device and the chromaticity value of the "universal" color space, which is the color description file of the device.

File header, which contains the basic information of the color feature file, such as file size, type of color management method, version of file format, device type, color space of the device, chrominance space of the feature file, operating system, device manufacturer, color restoration target, medium of the manuscript, light source chrominance data, etc., the file header accounts for 128 bytes. Tag table, which contains the tag number name, storage location, data size information, but does not contain the specific content of the tag, tag number name occupies 4 bytes, and each item of the tag table accounts for 12 bytes. Tag element data, it is in accordance with the tag table instructions, in the specified location to store the color management required by a variety of information, according to the complexity of the tag information, the size of the tag data varies.

Firstly, for a manuscript with normal colors, scan input is carried out by scanner first. Since the scanner profile provides the corresponding relationship between the colors on the scanner (namely the three stimulus values of red, green and blue) and the chroma space of CIE1976Lab, the operating system can obtain the chroma value Lab of the manuscript color according to this conversion relationship.