Lossless compression method for large-format remote sensing image

Abstract

The invention discloses a lossless compression method for a large-format remote sensing image, and belongs to the field of image processing. The method comprises the following steps: dividing a large-format remote sensing image into independent coding regions which are not overlapped with each other; identifying the dynamic range of the pixel of each independent coding area, and determining the quantized bit number of the pixel; calculating a lossless compression parameter of each independent coding region according to the quantization bit number of each independent coding region; and according to the lossless compression parameter of each independent coding region, carrying out lossless compression on the independent coding region until lossless compression of the large-format remote sensing image is completed. According to the invention, a large-format remote sensing image is divided into a plurality of independent coding areas which are not overlapped with one another; the dynamic range of each independent coding area is identified as the local dynamic range of the large-format remote sensing image, the characteristic that the local dynamic range of the large-format remote sensing image is lower than the fixed dynamic range of the camera is effectively used, the overall lossless compression ratio is increased, compression parameters can be adjusted according to the local dynamic range, and lossless compression of the large-format remote sensing image is achieved.

Description

technical field [0001] The invention belongs to the field of image processing, and more specifically relates to a lossless compression method for large-scale remote sensing images. Background technique [0002] With the continuous development of our country in space fields such as earth observation and deep space exploration, the resolution of remote sensing images is increasing day by day, and the amount of data is increasing. The contradiction between the huge data volume of large-format remote sensing images and the limited downlink bandwidth of satellites and grounds has become the main contradiction restricting the development of the space field. Image compression technology is an effective way to solve this problem. [0003] The lossless compression ratio is closely related to the dynamic range of the camera image. Generally speaking, for the same scene, the smaller the number of quantization bits of the camera image, the higher the lossless compression ratio; the lar...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the defects and improvement needs of the prior art, the present invention provides a lossless compression method for large-scale remote sensing images, the purpose of which is to solve the problem that each image sub-block is still compressed using a uniform and fixed dynamic range, resulting in a relatively low compression ratio

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