40 results about "Quantization distortion" patented technology

It is an object to improve coding efficiency by suitably setting, with respect to input information in moving image coding, a parameter for quantization calculation at the time of quantization. Various parameters for quantization calculation are set by a parameter setter 103, quantization is performed with the set parameters for quantization calculation by a quantizer 102, a coding cost J is calculated from a generated code amount R and a quantization distortion amount R obtained as a result thereof, and a parameter judgment unit 107 for quantization calculation selects, as a parameter for quantization calculation having highest coding efficiency, a parameter by which the coding cost J becomes minimum.

A highly linear analog-to-digital (ADC) conversion system has an analog front-end device in cascade with a standard ADC converter, and a tunable digital non-linear equalizer. The equalizer corrects the quantization distortion, deviations from ideal response, and additive noises generated by the analog front-end device and ADC converter. The equalizer is formed by three main parts: Generate Function Streams Unit, Finite Impulse Response FIR filters and a summer. The equalizer receives the unequalized output from the ADC converter and generates a plurality of monomial streams in a systolic fashion. Each of the monomial streams is passed through a corresponding linear finite impulse response FIR filter. A convolution sum of all outputs from the FIR filters produces a unique equalized output with the non-linear distortion reduced to a satisfactory level. The FIR filter coefficients are determined by an Identity Equalizer Coefficient Unit, and a Test Signal Generator with different types of test signals. The FIR filter coefficients are set to minimize an error function.

The present invention relates to the compression of color image data. A combination of hard decision pixel mapping and soft decision pixel mapping is used to jointly address both quantization distortion and compression rate while maintaining low computational complexity and compatibility with standard decoders, such as, for example, the GIF / PNG decoder.

A transmit processor that includes a transmit frequency domain equalizer (TX FEQ) that pre-compensates packets in the frequency domain to flatten transmit filter response to improve spectral mask and reduce PER. The TX FEQ taps may be selected so that the average power at output equals the average power applied to the input. The TX FEQ may be designed to yield 64 QAM packets with no quantization distortion at the input of an Inverse Fast Fourier Transform (IFFT) processor. The 64 QAM constellation map points and TX FEQ gain values are selected to avoid exceeding the bit resolution of the IFFT processor. The tones may be bound together into zones to reduce implementation complexity by reducing the number of TX FEQ taps.

A FAWNA that allows high-speed mobile connectivity by leveraging the speed of optical networks. Specifically, SIMO FAWNA, which comprises a SIMO wireless channel interfaced with a fiber channel through wireless-to-optical interfaces. Received wireless signal at each interface are sampled and quantized prior to transmission. The capacity of the FAWNA approaches the capacity of the architecture exponentially with fiber capacity. It is also shown that for a given fiber capacity, there is an optimal method of operating wireless bandwidth and number of interfaces. An optimal method to divide the fiber capacity among the interfaces is shown, which ensures that each interface is allocated a rate so that noise is dominated by front end noise rather than by quantization distortion. A method is also presented in which, rather than dynamically changing rate allocation based on channel state, a less complex, fixed rate allocation may be adopted with very small loss in performance.

The present invention relates to the compression of color image data. A combination of hard decision pixel mapping and soft decision pixel mapping is used to jointly address both quantization distortion and compression rate while maintaining low computational complexity and compatibility with standard decoders, such as, for example, the GIF / PNG decoder.

A dither system for a quantizing device, such as a multi-stage pipelined analog-to-digital converter (ADC), derives a dither signal from a clock signal having a sample frequency, the dither signal having a frequency that is one-third of the sample frequency. The dither signal is easily converted to analog and added at the input of the quantizing device to an analog signal to be digitized. A cancellation signal circuit generates a cosine-wave signal from a digital version of the dither signal and programmable coefficients that are a function of amplitude and phase. The cosine-wave signal is combined with the digital output signal from the quantizing device to produce a corrected digital output signal having reduced quantization distortion.

The present invention relates to the compression of color image data. A combination of hard decision pixel mapping and soft decision pixel mapping is used to jointly address both quantization distortion and compression rate while maintaining low computational complexity and compatibility with standard decoders, such as, for example, the GIF / PNG decoder.

The invention discloses a partition-based video steganography analysis method and system having the neighbourhood optimal probability. The method comprises the following steps of: selecting one from a partition mode set according to features of a video; for one video frame, counting a set of neighbourhood optimal SADs in all macro-block partition modes, calculating steganography analysis features of one video frame, and combining the features to obtain final steganography analysis features of one video frame; and, according to this, sequentially extracting steganography analysis features of all frames in one video. Oriented on detection of a video motion vector steganography method, aiming at the problem that the traditional prediction residual-based steganography analysis features are easily interfered by quantization distortion, the partition-based video steganography analysis method and system disclosed by the invention realize universal and precise steganography analysis to the motion vector steganography method through combination of quantization of macro-block partition to quantization distortion and neighbourhood optimal probability features.

Disclosed is an encoding device and others capable of suppressing quantization distortion while suppressing increase of a bit rate when encoding audio or the like. In the device, a dynamic range calculation unit (12) calculates a dynamic range of an input spectrum as an index indicating a peak of the input spectrum, a pulse quantity decision unit (13) decides the number of pulses of a vector candidate outputted from a shape codebook (14), and a shape codebook (14) outputs a vector candidate having the number of pulses decided by the pulse quantity decision unit (13) according to control from the search unit (17) by using a vector candidate element {−1, 0, +1}.

The present invention discloses a video data distribution unit, device and system. The main content of the present invention is that: a video driving module receives the video data and forward transmits the video data to a video data receiving device via a first matching resistor, and a video control module obtains the voltage of a first node in the first matching resistor and located at a video data output end and the voltage of a second node located at a video data input end, extracts a reverse control signal in a blanking zone when the voltage of the first node is higher than the voltage of the second node, transmits the extracted reverse control signal to a video data acquisition device and utilizes the reverse control signal to trigger a video interference elimination module to control the voltages of the two nodes of the first matching resistor, so that the extracted reverse control signal is not transmitted back, and the correct and continuous extraction and the forward transmission of the reverse control signal are guaranteed. Moreover, the digital analog conversion is not needed, and the quantization distortion and processing delay problems brought by the digital processing are avoided.

Disclosed are an analog-to-digital conversion method and apparatus capable of reducing quantization distortion in a receiver supporting multi-standard radios for which digital signal processing must be differently performed. The analog-to-digital conversion apparatus includes a first filter for filtering an input analog signal into a plurality of sub-band signals, a down-sampler for down-sampling the sub-band signals, a sub-band processor for allocating quantization bits for the sub-band signals, respectively, and digitizing the sub-band signals by using the allocated quantization bits, an up-sampler for up-sampling the digitized sub-band signals, and a second filter for reconstructing the sub-band signals into one digital signal. Multi-standard radio signals can be processed into digital signals in a receiver to which SDR is applied, and quantization distortion can be reduced during a procedure of converting the radio signal into the digital signal.

In a speaker distance calculation part of a speaker recognition apparatus, a quantization distance is obtained between a voice feature vector of a voice feature vector sequence produced from a voice of a speaker to be recognized and a representative vector of a codebook. The voice feature vector is quantized based on the quantization distance. And a quantization distortion is obtained by using a high order voice feature vector group of the voice feature vector sequence. In a recognition part of the speaker recognition apparatus, speaker recognition is executed based on the quantization distortion, which is for example, an average value of a plurality of the quantization distortions.

In a speaker distance calculation part of a speaker recognition apparatus, a quantization distance is obtained between a voice feature vector of a voice feature vector sequence produced from a voice of a speaker to be recognized and a representative vector of a codebook. The voice feature vector is quantized based on the quantization distance. And a quantization distortion is obtained by using a high order voice feature vector group of the voice feature vector sequence. In a recognition part of the speaker recognition apparatus, speaker recognition is executed based on the quantization distortion, which is for example, an average value of a plurality of the quantization distortions.

A distortion removal system for reducing the quantization distortion that results from quantization of a signal by sample-by-sample quantization techniques is disclosed. The distortion removal system uses the signal previously quantized with the sample-by-sample quantization techniques to determine an expected quantization distortion. The expected quantization distortion is determined for each of a plurality of frames of the signal. The expected quantization distortion is removed from each of the frames of the signal.

The invention discloses a learning-based low bit rate compressed image super-resolution reconstruction method, and the algorithm is divided into an offline part and an online part. In the offline part, the low-resolution image is first compressed with different compression quality parameter values; then the compressed image is filtered, and then the quantized distortion degree of the filtered compressed image is used as a feature, and the filtered LR image is classified according to its degree of distortion. Establish a classification sample library for multiple classes, and then use each type of sample to train the super-resolution model. In the online part, the input image is firstly filtered, and then its compression distortion category is determined. Then, according to the determination result, the sample library and super-resolution model of the corresponding category are selected to realize super-resolution restoration based on learning. Compared with other algorithms, the method of the present invention can adaptively adjust the matching sample library for input LR images with different degrees of distortion, and can effectively solve the impact of block effect distortion on image super-resolution, and directly solve the problem of low bit rate Compared with the super-resolution restoration of the distorted image, the image reconstructed by the method of the present invention has higher subjective and objective quality.

An image compression method comprises the following steps applied to at least one image: decorrelating the image by applying thereto a mathematical transform to obtain a set of coefficients, decomposing the image into blocks and, for each block of the image, quantizing the coefficients using a dead-zone uniform scalar quantizer having a semi-dead zone of size T and a quantization step size Δ, and coding the quantized coefficients, the size T of the semi-dead zone of the scalar quantizer being determined by minimizing the difference between an estimated quantization distortion D(T), dependent at least on size T, and a target quantization distortion Dc.

An image compression method comprises the following steps applied to at least one image: decorrelating the image by applying thereto a mathematical transform to obtain a set of coefficients, decomposing the image into blocks and, for each block of the image, quantizing the coefficients using a dead-zone uniform scalar quantizer having a semi-dead zone of size T and a quantization step size Δ, and coding the quantized coefficients, the size T of the semi-dead zone of the scalar quantizer being determined by minimizing the difference between an estimated quantization distortion D(T), dependent at least on size T, and a target quantization distortion Dc.

The invention discloses a method, a device and equipment for removing human eye perception redundant video codes. The method comprises the following steps: simulating perception characteristics of a human eye vision system to calculate a perception redundant threshold; and modulating the quantization coefficient to suppress the image. According to the method, the influence of quantization distortion in video coding on perception distortion is fully considered, multi-dimensional perception redundancy threshold values are calculated by simulating perception characteristics of a human eye visionsystem, different modulation coefficients are set according to different quantization QPs, and overlapping of the quantization distortion and the perception distortion is effectively reduced.

Provided are a quantization device and quantization method which reduce coding distortion with a small degree of calculation, and achieve adequate coding performance thereby. A multistage vector quantization unit (102) treats a number of candidates N which are designated prior to operation in the first-stage vector quantization unit (201-1), decrements the number of candidates by one beginning with the second-stage vector quantization unit (201-2-201-J) and continuing with each stage thereafter, and, if the number of candidates is three or less, assesses the quantization distortion at each such stage, treating the number of candidates at the following stage as a predetermined value P if the quantization distortion is greater than a prescribed threshold, and treating the number of candidates at the following stage as a value Q that is less than the predetermined value P if the quantization distortion is less than or equal to the predetermined threshold.

A FAWNA that allows high-speed mobile connectivity by leveraging the speed of optical networks. Specifically, SIMO FAWNA, which comprises a SIMO wireless channel interfaced with a fiber channel through wireless-to-optical interfaces. Received wireless signal at each interface are sampled and quantized prior to transmission. The capacity of the FAWNA approaches the capacity of the architecture exponentially with fiber capacity. It is also shown that for a given fiber capacity, there is an optimal method of operating wireless bandwidth and number of interfaces. An optimal method to divide the fiber capacity among the interfaces is shown, which ensures that each interface is allocated a rate so that noise is dominated by front end noise rather than by quantization distortion. A method is also presented in which, rather than dynamically changing rate allocation based on channel state, a less complex, fixed rate allocation may be adopted with very small loss in performance.

The invention provides a video compression method and device based on a just noticeable distortion model. The method comprises the steps: carrying out the DCT after an image is partitioned after a video frame is inputted, obtaining a spectrogram corresponding to each image block, and then calculating the texture complexity T of each image block; according to the texture complexity T of each imageblock, calculating a JND0 value corresponding to each image block on the premise of not considering quantization distortion; according to the JND0 value, calculating a JND value corresponding to eachimage block on the premise of considering quantization distortion; and according to the JND value corresponding to each image block, performing encoding preprocessing on the video frame, reducing a DCT coefficient value of a corresponding position of the video frame, and removing visual redundancy in the video frame to obtain an encoded video frame. The method has the advantages that visual redundancy in the video is effectively removed, larger compression gain is obtained, and the method better conforms to the characteristics of a human eye visual system.

The invention discloses a multi-level codebook vector quantitative method for compressed encoding of a hyperspectral remote sensing image and relates to the technical field of image processing. According to the method, a spectral vector of the hyperspectral image is divided into a low-dimension part, a middle-dimension part and a high-dimension part according to the distortion condition, then a large-size codebook is adopted in the low-dimension part with large distortion, a medium-size codebook is adopted in the middle-dimension part with not large distortion, a small-size codebook is adopted in the high-dimension part with small distortion, and therefore the multi-level codebooks are adopted, the mode that only a quarter of the weight training code index of the low-dimension part is extracted after dispersion degrees are ranked is combined, and the targets of effectively reducing the quantizing distortion of the hyperspectral image and obviously reducing calculation amounts of all parts are achieved with the same compression ratio. On the condition of the low calculation complexity, high-quality compressed encoding of the hyperspectral image is achieved with higher speed, and the method has the actual application value and is a hyperspectral image lossy and nearly lossless compression scheme good in compression performance.

The invention relates to a method for processing quantization distortion information of the DCT coefficient in video coding, which comprises the steps of S1, loading a distribution model of the DCT coefficient, wherein the distribution model of the DCT coefficient is composed of a Laplacian distribution part and a uniform distribution part; S2, optimizing the uniform distribution part of the distribution model of the DCT coefficient; S3, determining a quantization distortion estimated value function DLPTCM according to the distribution model of the DCT coefficient and a quantization reconstruction method; and S4, optimizing the quantization distortion estimated value function according to the optimized tail uniform distribution part of the distribution model of the DCT coefficient. Compared with the prior art, a quantization distortion estimation algorithm is calculated for a DZ+UTQ quantization method on the basis of a quantization distortion calculation method and the distribution model of the DCT coefficient, and the quantization distortion estimation algorithm in allusion to the construction rules well solves the application thereof in other optimization algorithm fields.

A quantization device and quantization method are provided that reduce coding distortion with a small degree of calculation and achieve adequate coding performance thereby. A multistage vector quantization unit treats a number of candidates N that are designated prior to operation in the first-stage vector quantization unit, decrements the number of candidates by one beginning with the second-stage vector quantization unit and continuing with each stage thereafter. If the number of candidates is three or less, the multistage vector quantization unit assesses the quantization distortion at each stage, treating the number of candidates at the following stage as a predetermined value P if the quantization distortion is greater than a prescribed threshold, and treating the number of candidates at the following stage as a value Q that is less than the predetermined value P if the quantization distortion is less than or equal to the predetermined threshold.

The present invention relates to the compression of color image data. A combination of hard decision pixel mapping and soft decision pixel mapping is used to jointly address both quantization distortion and compression rate while maintaining low computational complexity and compatibility with standard decoders, such as, for example, the GIF / PNG decoder.