495results about How to "Reduce bit rate" patented technology

The invention discloses a motion vector forecasting method in a resolution quantizing structure, wherein, forecasting motion vectors of macro blocks in enhancement layers are acquired by utilization of relativity of motion vectors of a time domain, a space domain and an interlayer domain. The realization process is that: on the time domain, candidate motion vectors of the time domain are acquired from motion vectors of macro blocks with the same position with the prior frame; on the space domain, candidate motion vectors of the space domain are acquired from motion vectors of adjacent blocks; on the interlayer domain, candidate motion vectors of the interlayer domain are acquired from corresponding motion vectors with low space domain resolution hierarchy; candidate motion vectors with minimum motion estimation cost are selected to be forecasting motion vectors by selection among the candidate motion vectors of the time domain, the space domain and the interlayer domain. The invention has the advantages of capability of acquiring more accurate forecasting motion vectors, capability of compressing code rate of motion vectors, and obtaining of performance gain.

An encoder/decoder is based on a combination of two audio or video channels to obtain a first combination signal as a mid-signal and a residual signal derivable using a predicted side signal derived from the mid-signal. A decoder uses the prediction residual signal, the first combination signal, a prediction direction indicator and prediction information to derive decoded first channel and second channel signals. A real-to-imaginary transform can be applied for estimating the imaginary part of the spectrum of the first combination signal. The prediction signal used in the derivation of the prediction residual signal, the real-valued first combination signal is multiplied by a real portion of the complex prediction information and the estimated imaginary part of the first combination signal is multiplied by an imaginary portion of the complex prediction information.

The invention relates to a video compressing and encoding method with an alpha transparent channel, comprising the following steps of: inverting the acquired video image to the image in the format of RGB or YUV4:4:4/YUV4:2:2/YUV4:2:0; compressing the acquired data in the alpha transparent channel in a no-damage mode; encoding and compressing video data for the video image in the specific format according to the frame format of MPEG-2 I and saving the compressed data in the alpha transparent channel in the compressed data structure of the video image. The method realizes the encoding of a specific video picture, can use a standard MPEG2 encoder for encoding, and effectively reduces video bitrate when ensuring the high quality of the video so as to realize the video data encoding with high quality, high efficiency and low cost. Because the data of the alpha transparent channel and the compressed data of the video image are saved in the same file, the video compressing and encoding method not only simplifies the process of processing the image at the later period and the information sharing between file management and a program, but also reserves the original video which is not added with the data of the alpha transparent channel.

The embodiment of the invention discloses a prediction coding and decoding method between frames, comprising the steps as follows: a coding end determines the coding type and carries out coding operation by comparing the gained template match movement vector of the current block with the movement vector prediction value; a decoding end receives code streams coming from the coding end and determines the decoding type and carries out the decoding operation by comparing the gained template match movement vector of the current block and the movement vector prediction value. The embodiment of the invention also discloses a coding device and a decoding device used for prediction between frames. The method and the device can save code rate excellently during the prediction process between frames.

The invention discloses an intra-frame lossless compression coding method based on an HEVC (high efficiency video coding) frame, wherein the method is low in time complexity and high in prediction accuracy and increases compression ratio. By the aid of the HEVC frame, a coding unit can be adaptively divided according to image flatness, the best division scheme is determined, and the optimal prediction mode is selected. DPCM (differential pulse code modulation) differential codes are used for preliminary prediction, prediction errors are possibly large when only the differential codes are used for an area with complex texture, and accordingly, prediction values are corrected for the area by means of error compensation. By combining the two methods, reduction of time complexity and improvement of prediction accuracy can be effectively compromised. Distribution characteristics of residual errors depend on the prediction mode, so that the scanning sequence of the residual errors is determined according to the prediction mode, and entropy coding can be more effective.

The invention discloses a method for expressing three-dimensional scenes. The method comprises the following steps: firstly, according to input multipath video image sequences and information extracted from each video image sequence, identifying and extracting the semanteme and the edge of an object in an actual scene and acquiring the depth information of the three-dimensional scene, and segmenting a video image at a middle view point on the basis of the depth information; adding block information extracted from video images of other view points in the blocked position of a blocked object according to the block relation between the segmented objects; and finally, according to the extracted depth information, expressing the depth of each object by a depth function or by both depth level and depth change mode. The invention also discloses a television system for processing input multipath video image data by the method.

The invention discloses a planar projection method and a coding method of a 360-degree panoramic video. Active region area of a plane figure formed by projecting a spherical surface to a plane is just equal to area of spherical surface, thus, area of an object can be guaranteed to be constant and be stretched or resized never; and according to the corresponding coding method of the 360-degree panoramic video, almost 40% of blank region is processed by a skipped macroblock mode, only limited bit needs to be coded, little data is consumed, proportion in a whole frame is very low, and it can be considered that only the active region consumes data, thus, coding for almost 40% of figure area is saved, and corresponding code rate is saved.

The invention discloses a video coding method for coding blocks inside the embedded frame; in every fixed frame interval, the invention can perform forcible frame internal coding in a specified region for a preceding estimated frame (P frame); the macro block reconstructed in predication for coding blocks in reference of the forcible frame can be deemed as a preferential reference block; if the reference block pixels in the macro block coding are inside the coding block or preferential reference block in the frame, the reconstructed macro block is still a preferential reference block. The preferential reference block can be reconstructed from the coding block frame inside the embedded frame. The invention is applicable to video monitoring and video conferences and able to increase I frame interval on the premise of guaranteeing random access points; therefore, the invention can lower bit spending.

A B picture mode determining method and apparatus in a video coding system includes the steps of: setting sum of absolute difference (SAD) initial values of a 4×4 and 16×16 intra prediction mode, a forward prediction mode, a backward prediction mode, a bi-directional prediction mode and a direct prediction mode; calculating the SAD values of each mode; and selecting a mode having the smallest SAD value from the SAD values of the modes as a prediction mode for a B picture coding. A penalty value in consideration of the overhead bit of each mode is set as an SAD initial value, and especially, in order for the direct mode to be selected for the flat regions having the zero motions, the SAD initial value of the direct mode is set as −16×QP₀(QP), so that the bit rate is considerably reduced and the coding performance of image information can be improved.

The delay in a multi-channel audio coding apparatus and a multi-channel audio decoding apparatus is reduced. The audio coding apparatus includes: a downmix signal generating unit (410) that generates, in a time domain, a first downmix signal that is one of a 1-channel audio signal and a 2-channel audio signal from an input multi-channel audio signal; a downmix signal coding unit (404) that codes the first downmix signal; a first t-f converting unit (401) that converts the input multi-channel audio signal into a multi-channel audio signal in a frequency domain; and a spatial information calculating unit (409) that generates spatial information for generating a multi-channel audio signal from a downmix signal.

The invention discloses a method for encoding a range image in a stereo-television system. The method comprises the following steps: 1) the edge strength value of each pixel in the range image is calculated, and then the edge strength value of each macroblock is calculated based on the edge strength value of the pixel point; 2) all the macroblocks in the range image are divided into three types, i.e., strong edge macroblocks, medium edge macroblocks and weak edge macroblocks; 3) the lower quantification parameter is configured for the strong edge macroblocks, the medium quantification parameter is configured for the middling edge macroblocks and the higher quantification parameter is configured for the weak edge macroblocks; and 4) the range image is encoded by utilizing the video coding technique based on the quantification parameter configured for all the macroblocks in the range image. The lower quantification parameter is configured for the strong edge macroblocks, so that the edge information of the range image is effectively protected and the quality of the free viewport image description of the client is improved.

The invention discloses a panoramic video positive mapping method and a panoramic video reverse mapping method, and relates to the field of a VR (Virtual Reality) video. In the invention, according to the positive mapping method, based on a main viewpoint, regions I, II and III on a spherical surface are respectively mapped to corresponding regions on a plane, wherein the region I corresponds to a region with an included angle of 0 degree to Z1, the region II corresponds to a region with an included angle of Z1 to Z2, and the region III corresponds to a region with an included angle of Z2 to 180 degrees. According to the panoramic video positive mapping method, a spherical surface corresponding to a panoramic image A is mapped onto a plane square image B; and according to the panoramic video reverse mapping method, the plane square image B is mapped back to the spherical surface to carry out rendering playing. According to the panoramic video positive mapping method and the panoramic video reverse mapping method which are disclosed by the invention, a resolution of the video can be greatly reduced, a code rate of panoramic video encoding and complexity of encoding and decoding are effectively reduced, and the aims of reducing the encoding code rate and ensuring video quality of an ROI region are fulfilled.

The invention discloses an audio bandwidth extension coding and decoding method and device based on a deep neutral network. The device includes a coding unit and a decoding unit. The coding unit includes an envelope preprocessor module, a high-frequency parameter extraction module, a low-frequency coding module and a code stream generation module. The decoding unit includes a code stream input module, a high-frequency parameter decoding module, a low-frequency signal decoding module, an auto-encoder parameter prediction module, a deep neutral network fine structure prediction module, a high-frequency signal reconstruction module, and a signal synthesis module. A fine structure of a high-frequency portion is predicated through autocorrelation between a signal low-frequency portion and a signal high-frequency portion by using a deep neutral network prediction method; then, the fine structure and edge information, obtained by a coding end, of the high-frequency portion are combined, and the signal high-frequency portion is reconstructed; and finally, the signal low-frequency portion and the signal high-frequency portion are fused, and a final recovery signal is obtained. Compared with a conventional method, the method has the advantages that the code rate is greatly reduced, and the tone quality is equivalent to that of the conventional method.

The present invention discloses a code integrating system and method and a decode integrating system and method, which belongs to the multimedia signal processing and information source coding field. The code integrating system comprises a receiving module, an extracting module, a sort module, a sub-coder, a control module, a merge module and a packing and transmitting module; the decode integrating system comprises a receiving and unpacking module, an analyzing module, a sub-decoder, a control module and a buffer memory outputting module. The code integrating method comprises that relevant information is extracted from the multimedia signal and one route main signal; the main signal or the multimedia signal is classified; the main signal is coded by the sub-coder, and then merged with various parameters and outputted after packing. The decode integrating method comprises that code stream data is received, the main signal is gained by decoding after unpacking and analyzing, and the main signal or the processed main signal is outputted. The present invention can fully exert the ascendancy of various individualized multimedia coder, and meet the requirements of subjective feeling characteristics and different channels.

The invention relates to a loop filter method used in image code process. Wherein, it comprises: first, calculating the number of similar points in the margin of filtered code block, and according to said number and if there is frame internal block, to decide the block effective value of said code block; then according o the pixel difference between two sides of block margin, judging if the block margin is the real edge of picture; at last, processing filter treatment on the code block according to the block effective value, when it is false edge. The invention improves the flat area filtration, to obtain better effect on the block removal effect of flat area.

The invention discloses a multi-viewpoint video signal coding method based on vision. The method is characterized in that the interested area of a video image is divided through setting a vision significance image of a coded video image; and in the subsequent coding process, smaller coding quantization parameters are adopted at the interested areas of human eyes, while greater coding quantization parameters are adopted at non-interested areas of human eyes. Although less code rates are distributed for the areas with lower attention of the human eyes for the method provided by the invention, the areas can not abstract the attentions from the human eyes for distortion caused by the coding, the influence to the whole quality of the image is not obvious, and simultaneously the code rates are saved greatly; and greater code rates are distributed at areas with high attention of the human eyes, and the whole subjective vision quality of decoding images can be improved, thus the efficiency of multi-viewpoint video signal decoding is improved.

The invention discloses a new asymmetrical panoramic video mapping method and a corresponding inverse mapping method. The mapping method comprises the steps of mapping a sphere corresponding to a panoramic image or a video A into a two-dimensional image or a video B; projecting the sphere to an isosceles rectangular pyramid with a quadrate bottom surface, and then projecting the rectangular pyramid to a plane; adopting isometrical projection for a region of a main viewpoint in projection and adopting a higher sampling density to ensure high video quality of the region of the main viewpoint; and adopting a lower sampling density for a region of non-viewpoint to save a code rate. With the asymmetrical mapping technology for the panoramic video, the resolution ratio of other regions in the video is greatly reduced and the code rate needed for encoding of a virtual-reality video is effectively saved on the premise of guaranteeing the video quality of the region of the main viewpoint unchanged. The asymmetrical mapping technology for the panoramic video provides a method for mapping the video from the plane to the sphere; and through the method, a planar video can be mapped back to thesphere for rendering and viewing.

The invention discloses multi-channel video stream encoder and decoder based on the depth image rendering. When encoding the video stream, the multi-channel video stream encoder and decoder can also encode the central channel video stream image frame and the depth map according to the video encoding standard method; the predicting map of the neighboring auxiliary channel to be encoded can be obtained by adopting the depth image rendering technology according to the image frame and the depth map after the channel is reconstructed, and converting, quantizing and entropy encoding can be performed to the shielding information. When the multi-channel video compression code is decoded by the multi-channel video stream encoder and decoder, the physiologic tendency of the human visual system can be utilized, and a virtual channel positioned at the center position of the two neighboring channels can be obtained by adopting the depth image rendering technology according to the image frames and the depth maps of the two neighboring channels. At the display terminal where the decoder of the invention is adopted to output the video stream, each vertical visual point is composed of a high-quality channel and a virtual channel, and the audience can get the good vertical visual experience.

The invention belongs to the technical field of video processing, and particularly relates to a stereoscopic video perception and coding method for a just-noticeable error model based on DOF. The method includes the steps that (1) a brightness JND model based on the DOF and parallax is calculated; (2) a texture JND model based on parallax is calculated; (3) the JND model DJND (x,y) based on the DOF is obtained according to a nonlinear combination model; (4) the JND model based on the DOF is used for stereoscopic coding by resetting quantization parameters. By means of the method, time, space and inter-view redundancy can be effectively eliminated, S3D video image quality and vision comfort are successfully improved, a texture and an edge area keep a very comfortable vision effect, and a stereoscopic video code rate is greatly lowered on the premise that stereoscopic visual perception quality is improved and maintained.

A system and method for bandwidth management by controlling the bit rate of a signal stream in real time according to available link bandwidth. Applications include multiple-channel video data streams over a limited-bandwidth link such as a Digital Subscriber Line. A video signal is transrated at the head end to multiple streams having different bit rates, by a multirating device which sends the multiple streams over a network, along with metadata containing information about the data structure and parameters of the streams. At the network access edge, a demultirating device uses the metadata to select the stream with the highest video quality whose bit rate does not exceed the available bandwidth of the end-user's access link. This scheme provides multiple unicast signals to different end-users in place of a single multicast signal, supports multiple high-definition channels over a limited bandwidth link, and is compatible with standard encryption methods.

A novel method and apparatus for efficiently coding and decoding data in a data transmission system is described. A concatenated coding scheme is presented that is easily implemented, and that provides acceptable coding performance characteristics for use in data transmission systems. The inventive concatenated channel coding technique is well suited for small or variable size packet data transmission systems. The technique may also be adapted for use in a continuous mode data transmission system. The method and apparatus reduces the complexity, cost, size and power consumption typically associated with the prior art channel coding methods and apparatuses, while still achieving acceptable coding performance. The present invention advantageously performs concatenated channel coding without the necessity of a symbol interleaver. In addition, the present invention is simple to implement and thereby consumes much less space and power that do the prior art approaches. The present invention not only eliminates the need for a symbol interleaver between the outer and inner codes, but it also enjoys a drastically reduced implementation complexity of the inner code Viterbi decoder. The preferred embodiment of the present invention comprises an inner code having short length block codes derived from short constraint length convolutional codes utilizing trellis tailbiting and a decoder comprising four four-state Viterbi decoders having a short corresponding maximum length. The inner code preferably comprises short block codes derived from four-state (i.e., constraint length 3), nonsystematic, punctured and unpunctured convolutional code. One significant advantage of the preferred embodiment of the present concatenated coding technique is that packet data transmission systems can be designed to have variable coding gains and coding rates.

This invention relates to a disguise communication method based on phone identification used in military secrecy communicatioin and facsimile apparatus system including: generating secret information code stream based on phone identification, serial and parallel transformation and generating being inserted cryptographs based on random cryptographic keys, testing cleartext sonant frame formant and insertion of random cryptograph information and secret information extraction in the following steps: 1, generation of water print and insertion, 2, extraction of water print.