5 results about "Image compression" patented technology

The invention discloses a hybrid image compressing method based on block classification. In the invention, blocks are divided into text/ image block, natural image block and hybrid block according to different features of text/image area and natural image area of original images in the aspect of color and texture; then a compression mode in which palette coding, Hextile coding and LZW coding are combined is used in the text/ image block, a JPEG lossy compression mode is used in the natural image while the algorithm of the combination of the two modes is used in the hybrid block. The invention has the advantages that based on the block classification method, the text/image area and the natural image area can be divided up accurately, and that the blocks are respectively encoded can keep rather acuminate edge of the text/image block so as to enhance visual effect on the basis of ensuring higher compression efficiency and upgrade the peak signal to noise ratio of reconstructed images; the complexity of the algorithm is lower.

The invention discloses an image compression encoding and decoding devices without visual loss, and encoding and decoding methods. The encoding method involves, first of all, dividing each row of an image into a plurality of micro-blocks, analyzing the micro-blocks, and determining the types of the macro-blocks; performing graphic encoding on graphic-type micro-blocks, performing intraframe mode prediction on non-graphic-type micro-blocks, and solving residual errors between current macro-blocks and predicted macro-blocks; analyzing the residual errors, and performing wavelet transformation on the residual errors needing wavelet lifting to obtain transformation coefficients; then according to image content, adaptively performing code rate control, and forming bit surface encoding on the input residual errors or the transformation coefficients to obtain final code rates; and finally, through combination with the predicted macro-blocks, reconstructing the macro-blocks. According to the invention, the purpose of high-quality and high-speed transmission of a single row of the image at a constant code rate is achieved, the image after compaction and an original image are free from the visual loss, the complexity is quite low, and fewer resources are occupied.

A method of image compression comprises the steps of recursively transforming a image using a Discrete Wavelet Transform. This creates a plurality of levels including at least a first level, multiple intermediate levels, and a low-low pass subband of the last level. The transformed image at each level is quantized, and datapacking the quantized image is performed. The step of datapacking further includes, encoding of the first level using adaptive run length of zero cofficients; encoding of the intermediate levels using run-length coding of zero coefficients and a predetermined two-knob huffman table for non-zero coefficients and encoding of the low-low pass subband using a low frequency packing algorithm.

The invention discloses an image compression method based on multi-scale feature coding. The image compression method comprises the steps: obtaining a selection vector through the averaging of the absolute values of gradient spectrums of image features of a training set, and guiding different channel features to select the coding resolution through the selection vector; meanwhile, recovering the features of low-resolution coding at a decoding end through a super-resolution network; and finally recombining the features of low-resolution coding with the features of high-resolution coding to forma complete feature spectrum, and mapping the complete feature spectrum back to an original image. According to the image compression method, difference processing is carried out according to the characteristics of the image characteristics, and the characteristics easy to recover from the context information are transmitted at low resolution, so that the code rate is saved; and for complex fine features, high-resolution transmission is adopted, so that the loss degree is reduced.

The invention provides a processor for screening aviation image information which belongs to the aviation electronic field. The processor includes a power supply module, an image collecting module, an electronic image stabilization module, a moving target detection module, an image compressing module, an image simulation display module and a serial port module. The screening processor is inputted in a stimulation signal with PAL standard that is converted into a digital image through the image sampling module, then the image is processed anti-shake by using the electronic image stabilization module, one route of the anti-shake image is processed moving target detection and outputting image with PAL standard and through the image stimulation display module, other route is processed image compression and outputs compression data through the serial port module. The invention has advantages of low consumption, high flexibility and real time and so on, can satisfy needs of air patrol and dynamic real-time monitor in many industries such as public security, traffic, safety supervision, country's territory, sea, petroleum, water conservancy, electrical power, urban construction, agriculture, forest industry and environmental protection and so on by combining with various industry appliance data processing and analysing software.