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:
Jul. 13, 2004
Filed:
Oct. 09, 2001
Robert N. Hurst, Hopewell, NJ (US);
Sarnoff Corporation, Princeton, NJ (US);
Abstract
Processing is applied to convert an input compressed video bitstream into an output compressed video bitstream having a different bit rate and/or representing different imagery from the input bitstream. The bitstream conversion processing is adjusted based on control parameters that are generated by comparing analogous measurements made to the input and output bitstreams so that subsequent measurements of the output bitstream will more closely match subsequent measurements of the input bitstream. In certain embodiments, the bitstream conversion processing involves decoding the input bitstream, optionally applying image processing functions to the resulting decoded video data, and re-encoding the resulting processed video data to generate the output bitstream. In one embodiment, the quantization data used during quantization of DCT coefficients during the re-encoding process are scaled using quantization re-scale factors (QRFs) generated by comparing the arrival margin for each frame in the input bitstream to the arrival margin for the corresponding frame in the output bitstream, where the arrival margin is defined as the amount of time between when the last bit of a frame has entered the decode buffer and when that frame is removed from the buffer.