公开(公告)号：US20030090591A1

公开(公告)日：2003-05-15

申请号：US10243081

申请日：2002-09-12

Applicant: STMicroelectronics S.r.I.

Inventor： Davide Concion ,  Emiliano Piccinelli ,  Danilo Pau

IPC: H04N005/14

CPC classification number: H04N19/40 ,  H04N19/59

Abstract: A process for format conversion of DCT macroblocks in an MPEG video bitstream that are divided into blocks, each of which includes a plurality of microblocks. In each DCT block, the significant frequencies are identified and preserved, isolating a corresponding microblock preferably consisting of the microblock on the top left of each block and setting to zero the coefficients of the remaining microblocks. On the microblock thus isolated there is performed an inverse discrete cosine transform, and the microblock thus obtained is merged with the homologous microblocks obtained from the other blocks comprised in a respective starting macroblock, so as to give rise to a merging block. The merging block thus obtained undergoes a discrete cosine transform so as to obtain a final block, which can be assembled into a macroblock with converted format.

Abstract translation: MPEG视频比特流中的DCT宏块的格式转换处理，被分成块，每个块包括多个微块。 在每个DCT块中，识别和保存有效频率，隔离优选地由每个块的左上角的微块组成的相应微块，并将剩余微块的系数设置为零。 在这样隔离的微块上，执行逆离散余弦变换，并且由此获得的微块与从包含在相应起始宏块中的其他块获得的同源微块合并，以产生合并块。 如此获得的合并块经历离散余弦变换，以获得最终的块，其可以被组合成具有转换格式的宏块。

公开(公告)号：US20020186774A1

公开(公告)日：2002-12-12

申请号：US10075087

申请日：2002-02-11

Applicant: STMicroelectronics, S.r.I.

Inventor： Danilo Pau ,  Daniele Alfonso ,  Fabrizio Basso ,  Emiliano Piccinelli ,  Alessandro Cremonesi

IPC: H04N007/12

CPC classification number: H04N19/59 ,  H04N19/40 ,  H04N19/48 ,  H04N19/90

Abstract: A process and a system is described for generating an MPEG output bitstream starting from an MPEG input bitstream. The output bitstream has a resolution modified with respect to the resolution of the input bitstream. -In the input bitstream, first portions that substantially do not affect and second portions that do affect resolution variation are distinguished. The second portions are then subjected to a function of modification of the resolution obtained by filtering the second portions in a domain of the discrete cosine transform, and then are transferred to the output bitstream. A corresponding computer program product is also provided.

Abstract translation: 描述了从MPEG输入比特流开始生成MPEG输出比特流的过程和系统。 输出比特流具有关于输入比特流的分辨率修改的分辨率。 - 在输入比特流中，区分基本上不影响的第一部分和确实影响分辨率变化的第二部分。 然后对第二部分进行通过对离散余弦变换的域中的第二部分进行滤波而获得的分辨率的修改的功能，然后被传送到输出比特流。 还提供了相应的计算机程序产品。