50results about How to "Improve subjective and objective quality" patented technology

The invention discloses a learning-based low-bit-rate compression image super-resolution reconstruction method. The learning-based low-bit-rate compression image super-resolution reconstruction method comprises the steps: offline part: firstly compressing low-resolution images by adopting different compression mass parameter values; then filtering the compressed images, taking the quantizing distortion degrees of the filtered compressed images as characteristics, classifying the filtered LR images according to the distortion degrees and establishing a classified sample library, and performing super-resolution model training on all samples respectively. In an online part, the flowing steps are carried out: firstly, filtering input images, then judging a compression distortion class, selecting the sample library and the super-resolution model of the corresponding class according to the judgment result, so as to realize the learning-based super-resolution restoration. Compared with other algorithms, through using the method, the sample library can be self-adaptively regulated so as to match the input LR images according to different distortion degrees, the influence of blocking effect distortion on the super-resolution of the images can be effectively overcome, and compared with the method of directly performing super-resolution restoration on the low-bit-rate distortion images, the images reconstructed by adopting the method has high subjective and objective quality.

The invention relates to a local feature transformation based face super-resolution reconstruction method. The method includes: performing nonnegative matrix decomposition for a low-resolution sample library matrix so as to obtain a local feature expression of a low-resolution image; transforming local features to a global feature space by the aid of a transformation relation between the local feature expression and a sample space reconstruction coefficient; as for the inputted low-resolution image, acquiring possessed features of the low-resolution image, then transforming to a sample space so as to obtain a global feature, and using a high-resolution sample library to substitute for a low-resolution sample library so as to obtain a high-resolution image; and using the high-resolution image obtained by reconstruction as an initial value, using a maximum posterior probability frame for iterative optimization of the inputted low-resolution image so that better image reconstruction quality is obtained. A global face super-resolution algorithm based on transformation of the image local features to the global feature is provided, detail representation capability of the global face algorithm is enhanced, and objective image quality of the reconstructed high-resolution image is improved.

Provided is an improved sample adaptive offset filtering method based on histogram analysis. The method comprises the steps of analyzing histogram distribution according to gray values of sample values in coding tree blocks of a reconstruction frame, classifying the coding tree blocks according to the histogram distribution, dividing adaptive sample offset filtering into a narrow coding tree block mode, a wide coding tree block mode, a double-center coding tree block mode and a default mode, respectively calculating the optimal rate distortion cost values under different classification modes, selecting the mode corresponding to the minimum rate distortion cost value as a truly-adopted band filtering mode and coding and transmitting a corresponding band starting position and an offset value. Three more accurate and more efficient filtering classification methods are newly added according to the characteristics of coding tree block histogram distribution so as to improve the accuracy of the sample adaptive offset filtering method, and the subjective and objective quality of videos can be effectively improved under the condition of same code rate.

The invention discloses a method for hiding the loss errors of three-dimensional video macro blocks. According to the method, the motion and static states of the macro blocks in a lost frame are estimated by prejudging the magnitude of time domain relevance between adjacent time domain frames of the lost frame and adjacent frames among viewpoints, the macro blocks are classified into motion macro blocks and static macro blocks, and lost macro blocks are restored by adopting a direct time domain frame copying method specific to static macro blocks with high time domain relevance, so that the calculation complexity is low, and the subjective and objective quality of the type of lost macro blocks can be improved; and specific to the motion macro blocks, an optimal candidate macro block is selected from candidate macro blocks pointed by each vector in a candidate vector set of the lost macro blocks by adopting two boundary matching principles, optimally matched macro block recovery or multi-direction interpolation method recovery is adaptively selected according to the boundary distortion value of the optimal candidate macro block, so that the subjective and objective quality of the lost macro blocks moving vigorously can be improved, and a very good recovering effect can be achieved on the lost macro blocks positioned on the edge of an object.

A voice signal processing method according to an embodiment of the present disclosure for overcoming the problem includes: acquiring a real-time near-end noise signal; acquiring a far-end voice signal according to an incoming call; measuring subjective speech quality and perceptual-objective speech quality of test signals generated based on a reference signal and the real-time near-end noise signal; selecting at least one speech quality enhancement method based on the subjective speech quality and the perceptual-objective speech quality, and determining parameters that are to be applied to the selected at least one speech quality enhancement method; and enhancing speech quality of the far-end voice signal by using the selected at least one speech quality enhancement method, based on the determined parameters, :herein the test signals are generated by mixing the acquired real-time near-end noise signal with the reference signal whose speech quality is enhanced by applying a combination of parameter values to speech quality enhancement methods.

The invention discloses a DIBR method based on block projection. The method comprises the steps of firstly acquiring a color image of and a depth image of a reference viewpoint and vidicon geometrical parameters of two viewpoints, dividing a reference image into a plurality of block areas, carrying out projection change on each block area, finally integrating all block areas in a target viewpoint image, and repairing cavities to achieve a final target viewpoint image. The DIBR method doesn't directly use a point-by-point mode to carry out viewpoint change to generate new viewpoints, so that the target viewpoint image is prevented from being affected by the continuity of the depth image. Simulation experiments and actual data are utilized to compare the performance of a traditional method and the performance of the DIBR method based on the block projection to verify the effectiveness of the DIBR method. Furthermore, the target viewpoint drawing quality is improved, and the transmission bandwidth is reduced.

The invention belongs to the field of a 3D (three dimensional) video and relates to a processing method for a color aliasing and shadow part in three dimensional video virtual viewpoint synthesis. The method is realized by selectively mapping the color aliasing and shadow part corresponding to the left-right viewpoint depth map boundary part and judging whether the color aliasing and shadow part is remained or not. According to the method, the distortion of the synthesis virtual viewpoint boundary position caused by the color aliasing and shadow part is eliminated and the subjective quality and objective quality of the virtual viewpoints are improved.

Primary and alternate optimization procedures are used to improve the ITU-T G.723.1 speech coding standard (the “Standard”) by replacing the Hamming window of the Standard with an optimized window, with two windows, or with two windows and an additional performance of an autocorrelation method. When two windows replace the Hamming window, at least one of which is an optimized window, generally the first is used to determine optimized unquantized LP coefficients which are used to define an optimized perceptual weighting filter, and the second is used to determine optimized unquantized LP coefficients which are used to determine optimized synthesis coefficients. Optimized windows created using the primary and alternate optimization procedures and used in the Standard yield improvements in the objective and subjective quality of synthesized speech produced by the Standard. The improved Standard, methods, and window can all be implemented as computer readable software code.

The invention discloses low code rate video coding method and system. The low code rate video coding system comprises a first determination processing module, a first regular coding module, a second determination processing module, a second regular coding module, a next coding frame determination processing module and a next coding frame setting module. The low code rate video coding method monitors a visual sensitive area of a film source image, can perform timely regulation, can limit a coding mode of the area, and can improve subjective and objective quality of video compression when the complicate film source is compressed with a low code rate.

Primary and alternate optimization procedures are used to improve the ITU-T G.723.1 speech coding standard (the “Standard”) by replacing the Hamming window of the Standard with an optimized window, with two windows, or with two windows and an additional performance of an autocorrelation method. When two windows replace the Hamming window, at least one of which is an optimized window, generally the first is used to determine optimized unquantized LP coefficients which are used to define an optimized perceptual weighting filter, and the second is used to determine optimized unquantized LP coefficients which are used to determine optimized synthesis coefficients. Optimized windows created using the primary and alternate optimization procedures and used in the Standard yield improvements in the objective and subjective quality of synthesized speech produced by the Standard. The improved Standard, methods, and widows can all be implemented as computer readable software code.

The invention discloses a picture coding method and system. The method comprises the following steps: carrying out intraframe coding on macroblocks required to be coded to acquire the macroblocks of the intraframe coding; subtracting the luminance component in luminance blocks in the macroblocks of the intraframe and the luminance component in luminance blocks in the macroblocks required to be coded, subtracting the luminance component in Cr chrominance blocks in the macroblocks of the intraframe coding and the luminance component in Cr chrominance blocks in the macroblocks required to be coded, and subtracting the luminance component in Cb chrominance blocks in the macroblocks of the intraframe coding and the luminance component in Cb chrominance blocks in the macroblocks required to be coded to acquire a luminance difference block, a Cr chrominance difference block and a Cb chrominance block; coding at least one of the luminance difference block, the Cr chrominance difference block and the Cb chrominance block so as to realize additional coding on the macroblocks required to be coded; and adding an additional coding result of the macroblocks required to be coded and the macroblocks of the intraframe coding to acquire a final coding result of the macroblocks.