谷歌vp9编码方式草案.pdf

Network Working Group A. Grange Internet-Draft H. Alvestrand Intended status: Informational Google Expires: August 22, 2013 February 18, 2013 A VP9 Bitstream Overview draft-grange-vp9-bitstream-00 Abstract This document describes VP9, a video codec being developed specifically to meet the demand for the consumption of video over the Internet, including professionally and amateur produced video-on- demand and conversational video content. VP9 is an evolution of the VP8 video codec that is described in [bankoski-rfc6386] and includes a number of enhancements and new coding tools that have been added to improve the coding efficiency. The new tools that have been added so far include: larger prediction block sizes up to 64x64, various forms of compound INTER prediction, more modes for INTRA prediction, #8539;-pel motion vectors, 8-tap switchable sub-pixel interpolation filters, improved motion reference generation, improved motion vector coding, improved entropy coding including frame-level entropy adaptation for various symbols, improved loop filtering, the incorporation of the Asymmetric Discrete Sine Transform (ADST), larger 16x16 and 32x32 DCTs, and improved frame level segmentation. VP9 is under active development and this document provides only a snapshot of the current state of the coding tools as they exist today. The finalized version of the VP9 bitstream may differ considerably from the description contained herein and may encompass the exclusion or modification of existing coding tools or the addition of new coding tools. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Int