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:
A method for implementing B-frame prediction in video compression comprising the steps of (A) setting a prediction flag (i) “off” if B-frames are used for block prediction and (ii) “on” if B-frames are not used for block prediction, (B) if the prediction flag is off, generating an output video signal in response to an input video signal by performing an inverse quantization step and an inverse transform step in accordance with a predefined coding specification and (C) if the prediction flag is on, bypassing the inverse quantization step and the inverse transform step.
摘要:
The present invention discloses a system and method for rate control of MPEG video streams to achieve a target bit rate in a transcoder at the best visual quality possible. The invention monitors video buffer fullness for selecting the amount of rate reduction necessary to achieve a target bit rate. The invention also utilizes a method for selective requantization of DCT coefficients to assure visual quality.
摘要:
A method for implementing non-reference frame prediction in video compression comprising the steps of (A) setting a prediction flag (i) “off” if non-reference frames are used for block prediction and (ii) “on” if non-reference frames are not used for block prediction, (B) if the prediction flag is off, generating an output video signal in response to an input video signal by performing an inverse quantization step and an inverse transform step in accordance with a predefined coding specification and (C) if the prediction flag is on, bypassing the inverse quantization step and the inverse transform step.
摘要:
A method for deinterlacing a picture is disclosed. The method generally includes the steps of (A) generating a plurality of primary scores by searching along a plurality of primary angles for an edge in the picture proximate a location interlaced with a field of the picture, (B) generating a plurality of neighbor scores by searching for the edge along a plurality of neighbor angles proximate a particular angle of the primary angles corresponding to a particular score of the primary scores having a best value and (C) identifying a best score from a group of scores consisting of the particular score and the neighbor scores to generate an interpolated sample at the location.
摘要:
A method for transcoding from an MPEG-2 format to a VC-1 format is disclosed. The method generally comprises the steps of (A) decoding an input video stream in the MPEG-2 format to generate a picture; (B) determining a mode indicator for the picture; and (C) coding the picture into an output video stream in the VC-1 format using one of (i) a VC-1 field mode coding and (ii) a VC-1 frame mode coding as determined from the mode indicator.
摘要:
A method for transcoding from an MPEG-2 format to an H.264 format is disclosed. The method generally comprises the steps of (A) decoding an input video stream in the MPEG-2 format to generate a plurality of macroblocks; (B) determining a plurality of indicators from a pair of the macroblocks, the pair of the macroblocks being vertically adjoining; and (C) coding the pair of the macroblocks into an output video stream in the H.264 format using one of (i) a field mode coding and (ii) a frame mode coding as determined from the indicators.
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:
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.
摘要:
A method for processing an input signal is disclosed. The method generally includes the steps of (A) extracting a compressed signal and a first checksum from the input signal, (B) generating a decompressed signal by decompressing the compressed signal, (C) calculating a second checksum for the decompressed signal and (D) generating a result by comparing the first checksum to the second checksum.