Image compression method and apparatus

摘要

A method and apparatus for image compression. The method includes: calculating a total bit length that is needed for compressing any one segment line and an ideal bit length that is needed for compressing any one segment; for each segment in any one segment line, acquiring a quantization parameter and a compression mode for compressing the segment and an actual bit length that is needed for compressing the segment by using the acquired quantization parameter and compression mode; distributing a redundancy bit length of one or more simple segments in the segment line to one or more complex segments in the segment line, and re-acquiring quantization parameters and compression modes for compressing every complex segment of the one or more complex segments; and compressing every segment in the segment line by using the acquired quantization parameters and compression modes.

主权项

1. An image compression method for compressing an image to be compressed in units of segment and constituting a segment line by using all segments in one or more lines in the image to be compressed according to a predetermined setting, the method comprising:
calculating a total bit length that is needed for compressing a segment line and calculating an ideal bit length that is needed for compressing a segment in the segment line; acquiring a quantization parameter and a compression mode for compressing the segment and an actual bit length that is needed for compressing the segment by using the acquired quantization parameter and compression mode, wherein a segment whose quantization parameter is not larger than a predetermined threshold in the segment line is called a simple segment, and a segment whose quantization parameter is larger than the predetermined threshold in the segment line is called a complex segment; distributing a redundancy bit length of one or more simple segments in the segment line to one or more complex segments in the segment line, and re-acquiring quantization parameters and compression modes for compressing every complex segment of the one or more complex segments, wherein the redundancy bit length of the one or more simple segments is the sum of bit lengths obtained by subtracting the actual bit lengths from the ideal bit lengths of every simple segment of the one or more simple segments; and compressing every segment in the segment line by using the acquired quantization parameters and compression modes.