摘要:
The present invention discloses how a transcoder may be used to reduce the bit rate of an MPEG-2 stream by transmitting only the visible area of the movie specified by pan-scan directives. Because the pan-scan conversion is performed prior to transmission, not immediately before display, the non-viewed portion of video does not need to be transmitted.
摘要:
This invention discloses a fast two-dimensional inverse Discrete Cosine Transform (iDCT) that adapts to compressed video source statistics to reduce execution time. iDCT algorithms for sparse blocks eliminate calculations for some zero coefficients and are implemented with quad-word parallel single-instruction-multiple-data (SIMD) multimedia instructions. It is observed that end-of-block marker value histograms vary little within single shots. An adaptive control mechanism is proposed that selects the optimal set of iDCTs to prepare for an entire shot from its first frames (to reduce software overheads and penalties). This introduces no degradation of decoded video quality as compared with a conventional SIMD 8×8 iDCT implemented with Intel MMX instructions.
摘要:
A method for inverse telecine. The method generally includes the steps of (A) checking if a current field of a plurality of fields in a video sequence repeats in the video sequence according to a pattern-based approach where the current field fits a telecine pattern, (B) checking if the current field repeats according to a first pattern-less approach where the current field complies with at least one of a plurality of rules and (C) generating a signal for an encoder in (i) an asserted state if the current field repeats and (ii) a deasserted state if the current field does not repeat.
摘要:
A method for composite noise filtering is disclosed. The method generally includes the steps of (A) generating a selection value in response to a stationary check identifying one of a plurality of blendings for a current item of a current field, (B) generating a filtered item in response to one of (i) a first of the blendings between the current item and a first previous item co-located in a first previous field having an opposite phase of composite artifacts from the current field and (ii) a second of the blendings between the current item and a first motion compensated item from the first previous field and (C) switching between the first blending and the second blending in response to the selection value.
摘要:
A video decoder comprising (i) a post-processing filter block, (ii) a comfort noise addition block and (iii) a video value/range adjustment block, where the comfort noise addition block is integrated into a video output path of the video decoder. The post-processing filter block may be configured to perform one or more of noise reduction, spatial filtering and temporal filtering on luminance data. The comfort noise addition block may be configured to add comfort noise to the luminance data. The video value/range adjustment block may be configured to adjust one or both of a value and a range of the luminance data.
摘要:
A video encoder comprising an encoder circuit, a quantizer circuit and a control circuit. The encoder circuit may be configured to generate a number of coefficient values in response to a video stream and a number of quantized values. The quantizer circuit may be configured to generate the number of quantized values in response to the coefficient values, two or more quantization dead zones and two or more offsets. The control circuit may be configured to set the two or more quantization dead zones and the two or more offsets to different values. The two or more quantization dead zones and the two or more offsets are independently programmable.
摘要:
A method and apparatus for processing a video block extracted from an encoded bitstream. The method generally includes the steps of (A) generating a normal block by inverse transforming the video block, the normal block having a normal resolution, (B) generating an alternate block from the video block, the alternate block comprising image detail (i) present after the inverse transforming and (ii) absent from the normal block and (C) generating an output block based on the normal block and the alternate block, the output block having an output resolution greater than the normal resolution.
摘要:
The present invention is directed to an improved method for the binarization of data in an MPEG data stream. The invention makes use of unary binarization to create codewords up until an index threshold. Once the threshold has been met, succeeding code symbols have appended to them an exp-Golomb suffix. This hybrid binarization scheme reduces the number of binary codewords to be processed by a Binary Arithmetic Coder (BAC), thus reducing the computation required by the BAC.
摘要:
The present invention extends the generalized Lloyd algorithm (GLA) for vector quantizer (VQ) codebook improvement and codebook design to a new linearly-constrained generalized Lloyd algorithm (LCGLA). The LCGLA improves the quality of VQ codebooks, by forming the codebooks from linear combinations of a reduced set of base codevectors. The present invention enables a principled approach for compressing texture images in formats compatible with various industry standards. New, more flexible compressed texture image formats are also made possible with the present invention. The present invention enhances signal compression by improving traditional VQ approaches through the integrated application of linear constraints on the multiple pattern and signal prototypes that represent a single pattern or block of signal samples.
摘要:
This invention discloses an intra-frame complexity based dynamic GOP system and method for the encoding of MPEG-2 video streams. The present invention may be used as a rate control tool to improve video quality. The selective insertion of low complexity I frames in scene changes such as fades is disclosed. It is disclosed that the selective use of I frames in certain scene change situations can improve encoder performance, particularly when encoding at a low bit rate.