The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 2005
Filed:
Jun. 13, 2001
Shankar Moni, San Jose, CA (US);
Andrew W. Walters, San Jose, CA (US);
John A. Tardif, San Jose, CA (US);
Padma Parthasarathy, Fremont, CA (US);
Shankar Moni, San Jose, CA (US);
Andrew W. Walters, San Jose, CA (US);
John A. Tardif, San Jose, CA (US);
Padma Parthasarathy, Fremont, CA (US);
Microsoft Corporation, Redmond, WA (US);
Abstract
Systems and methods for transcoding a transport stream or a video stream. A video stream includes a quantization matrix and a quantization scale that define how DCT frequency coefficients are quantized. A transport stream is transcoded by updating the quantization matrix and/or the quantization scale such that a new set of DCT frequency coefficients may be generated. Typically the quantization scale and/or the quantization matrix are updated such that the DCT frequency coefficients are more coarsely quantized such that their encoding consumes fewer bits. The quantization matrix can be updated such that select frequency coefficients are affected. Transcoding can operate at any level of the video stream, such as the frame level, the slice level, or the macroblock level. The bit rate of the video stream can therefore be adjusted or altered according to a current quantization level and a current bit rate.