公开(公告)号：CA2796179C

公开(公告)日：2016-08-09

申请号：CA2796179

申请日：2001-12-18

Applicant: GEN INSTRUMENT CORP

Inventor： LIU VINCENT ,  CHEN JINGYANG ,  WU SIU-WAI

IPC: H04N19/14 ,  H04N7/50 ,  H04N19/142 ,  H04N19/177 ,  H04N21/44

Abstract: A controller allocates a bit size for a current frame in a group of pictures of a first compression-encoded digital video signal that is to be spliced following transmission of the group of pictures with a second compression-encoded digital video signal. The signals are spliced after a predetermined switching time. The spliced signals are buffered by a decoder buffer and then decoded by a decoder. When the second signal has a variable bit-encoding rate and the current frame is not decoded until after the predetermined switching time, the maximum bit size is determined in accordance with an estimate of the decoder buffer fullness at the predetermined switching time. When the second signal has a predetermined maximum variable bit-encoding rate and the current frame is not decoded until after the predetermined switching time, the minimum bit size is determined in accordance with the predetermined maximum bit-encoding rate of the second signal.

公开(公告)号：CA2457614C

公开(公告)日：2012-06-12

申请号：CA2457614

申请日：2002-08-09

Applicant: GEN INSTRUMENT CORP

Inventor： WU SIU-WAI ,  LIU VINCENT

IPC: H04N19/114 ,  H04N19/156 ,  H04N19/51

Abstract: The invention relates to an improved system and method for encoding digital images within frames for digital television transmission. Every anchor frame in a first pass encoder is encoded as a P-frame. Groups of macroblocks, such as slices in the P-frame, are alternately encoded as I-slices and P-slices. This allows both I and P encoding complexity to be computed in a single pass, without having to encode the same frame twice. Accordingly, the I-frame decision can be made at a second pass encoder instead of at the first pass encoder, thus taking advantage of a look-ahead pipeline architecture to more effectively align the I-frames with scene changes.

公开(公告)号：DE60231205D1

公开(公告)日：2009-04-02

申请号：DE60231205

申请日：2002-05-14

Applicant: GEN INSTRUMENT CORP

Inventor： LIU VINCENT ,  NEMIROFF ROBERT S ,  WU SIU-WAI

IPC: H04N21/234 ,  H04N21/236 ,  H04N21/81

Abstract: A mechanism for splicing advertisements, local programming and the like into a digital video transport stream is provided. In order to achieve proper splicing, an appropriate number of frames is inserted between bitstreams to properly close a GOP of the first bitstream into which a second bitstream carrying the spliced content is inserted. Program clock references (PCRs) of the bitstreams are adjusted as necessary in order to force continuity between the bitstreams. For inserting advertisements, the PCR of the program stream and ad stream can be tracked, and the PCR of the program stream can be used both before and after splicing. For local program insertion (which are typically substantially longer than advertisements), the PCR of the local program can be used, after adjustment thereof with an offset to maintain continuity at the splice point. The PTS and/or DTS of the inserted bitstream can be modified to keep them continuous at the splice point for both video and audio streams. The spliced bitstream is transcoded to maintain a desired output bit rate, and to provide overflow/underflow protection of the video buffers.

公开(公告)号：CA2449124C

公开(公告)日：2008-07-15

申请号：CA2449124

申请日：2002-05-14

Applicant: GEN INSTRUMENT CORP

Inventor： WU SIU-WAI ,  NEMIROFF ROBERT S ,  LIU VINCENT

IPC: H04N21/234 ,  H04N21/236 ,  H04N21/81

Abstract: A mechanism for splicing advertisements, local programming and the like into a digital video transport stream is provided. In order to achieve proper splicing, an appropriate number of frames is inserted between bitstream to properly close a GOP of the first bistream into which a second bitstream carrying the spliced content is inserted. Program clock references (PCRS) of the bitstreams are adjusted as necessary in order to force continuity between the bistreams. For inserting advertisements, the PCR of the program stream and ad stream can be tracked, and the PCR of the program stream can be used both before and after splicing. For local program insertion (which are typically substantially longer than advertisements), the PCR of the local program can be used, after adjustment thereof with an offset to maintain continuity at the splice point. The PTS an/or DTS of the inserted bistream can be modified to keep them continuous at the splice point for both video and audio streams. The spliced bitstream is transcoded to maintain a desired output bit rate, and to provide overflow/underflow protection of the video buffers.

公开(公告)号：DE69726508T2

公开(公告)日：2004-09-23

申请号：DE69726508

申请日：1997-08-04

Applicant: GEN INSTRUMENT CORP

Inventor： CHEN XUEMIN ,  LIU VINCENT

IPC: H04N7/32 ,  G06T7/00 ,  G06T9/00 ,  H03M7/40 ,  H04N13/00

Abstract: Disparity estimation between the right and left view pixel luminance values in a stereoscopic video signal is optimized by determining the minimum least-square-error between macroblocks of the right and left view pictures. Affine transform coefficients and disparity vectors which correspond to the minimum error are also determined and transmitted in the data stream for use by a decoder in reconstructing the right view picture. The scheme can be implemented either locally, at the macroblock level, or globally, at the picture level. At the macroblock level, least-square-error optimization may occur for each individual macroblock in the right view picture. In this case, affine transform coefficients are provided for each macroblock. At the picture level, the sum of the least-square-errors is minimized after the blocks of the right view picture are matched to the left view picture. In this case, only one set of affine transform coefficients are required for the entire right view picture. Or, block matching between an affinely transformed left view picture and the right view picture may be performed after minimizing the sum of the least-square-errors. The scheme is particularly useful in minimizing the effects of cross-channel luminance imbalances due to camera variations and scenes with significant changes in brightness or contrast, and is compatible with stereoscopic video systems such as the MPEG Multi-view Profile (MVP) system.

公开(公告)号：CA2396308A1

公开(公告)日：2003-12-25

申请号：CA2396308

申请日：2002-07-29

Applicant: GEN INSTRUMENT CORP

Inventor： HE YOUNG ,  LIU VINCENT ,  WU SIU-WAI

IPC: H04J3/04 ,  H04N7/24 ,  H04N7/26 ,  H04N7/50 ,  H04N7/58

Abstract: Methods and apparatus for statistical multiplexing in a dual pass encoding scheme are provided. A first pass encoder encodes alternate slices of anchor frames as I- slices and P- slices respectively in order to generate statistics fox both I and P frame encoding for the same anchor frame. A second pass encoder determines the encoding complexity estimates for a plurality of frames in a look-ahead pipeline and sums the encoding complexit y estimates of selective frames in the look-ahead pipeline to determine the initial need parameter for a current fi~ame to be encoded. The second pass encoder computes a need parameter for encoding the current frame based on the initial need parameter. The need parameter is used by a statmux processor to determine the encoding bit rate for second pass encoding of the current frame.

公开(公告)号：AU2002356070A1

公开(公告)日：2003-03-03

申请号：AU2002356070

申请日：2002-08-09

Applicant: GEN INSTRUMENT CORP

Inventor： WU SIU-WAI ,  LIU VINCENT

IPC: H04N19/114 ,  H04N19/156 ,  H04N19/51 ,  H04N7/26 ,  H04N7/50 ,  H04N7/36

Abstract: The invention relates to an improved system and method for encoding digital images within frames for digital television transmission. Every anchor frame in a first pass encoder is encoded as a P-frame. Groups of macroblocks, such as slices in the P-frame, are alternately encoded as I-slices and P-slices. This allows both I and P encoding complexity to be computed in a single pass, without having to encode the same frame twice. Accordingly, the I-frame decision can be made at a second pass encoder instead of at the first pass encoder, thus taking advantage of a look-ahead pipeline architecture to more effectively align the I-frames with scene changes.

公开(公告)号：CA2457614A1

公开(公告)日：2003-02-27

申请号：CA2457614

申请日：2002-08-09

Applicant: GEN INSTRUMENT CORP

Inventor： WU SIU-WAI ,  LIU VINCENT

IPC: H04N19/114 ,  H04N19/156 ,  H04N19/51 ,  H04N7/26 ,  H04N7/36 ,  H04N7/50

Abstract: The invention relates to an improved system and method for encoding digital images within frames for digital television transmission. Every anchor frame in a first pass encoder is encoded as a P-frame. Groups of macroblocks, such as slices in the P-frame, are alternately encoded as I-slices and P-slices. This allows both I and P encoding complexity to be computed in a single pass , without having to encode the same frame twice. Accordingly, the I-frame decision can be made at a second pass encoder instead of at the first pass encoder, thus taking advantage of a look-ahead pipeline architecture to more effectively align the I-frames with scene changes.

公开(公告)号：DE69429377T2

公开(公告)日：2002-08-22

申请号：DE69429377

申请日：1994-01-18

Applicant: GEN INSTRUMENT CORP

Inventor： LIU VINCENT ,  FOX JOHN

IPC: H04N7/32 ,  G06T1/60 ,  H04N5/14 ,  H04N7/26 ,  H04N7/36

公开(公告)号：CA2422125A1

公开(公告)日：2002-03-28

申请号：CA2422125

申请日：2001-08-20

Applicant: GEN INSTRUMENT CORP

Inventor： LIU VINCENT ,  NEMIROFF ROBERT S ,  LUTHRA AJAY ,  WANG LIMIN ,  WU SIU-WAI

IPC: H04N7/26 ,  H04N7/50 ,  H04N7/24

Abstract: An efficient processing system, such as for transcoding video data. In an embodiment that is suitable for single or multiple processor embodiments, a processing mode is set for each input video frame, e.g., as a full transcode mode (740), which uses motion compensation, a requantization mode (755), whi ch avoids motion compensation, or a bypass mode (750). The processing mode selection is based on a number or processing cycles that are available to process a frame, and an expected processing requirement of the frame. The bypass or requantization modes are selected to avoid a buffer overflow of th e processor.