2010-05-01から1ヶ月間の記事一覧

Chapter 6: Description of Algorithms / 第6章 アルゴリズムの詳細

VP8

As the intent of this document, together with the reference decoder source code, is to specify a platformindependent procedure for the decoding and reconstruction of a VP8 video stream, many (small) algorithms must be described exactly. 参…

Chapter 5: Overview of the Decoding Process / 5章 復号処理の概要

VP8

A VP8 decoder needs to maintain four YUV frame buffers whose resolutions are at least equal to that of the encoded image. These buffers hold the current frame being reconstructed, the immediately previous reconstructed frame, the most rece…

Chapter 4: Overview of Compressed Data Format / 4章 圧縮データフォーマットの概要

VP8

The input to a VP8 decoder is a sequence of compressed frames whose order matches their order in time. Issues such as the duration of frames, the corresponding audio, and synchronization are generally provided by the playback environment a…

Chapter 3. Compressed Frame Types / 3章 圧縮フレーム種類

VP8

There are only two types of frames in VP8. VP8にフレームの種類は二つしかない. Intraframes (also called key frames and, in MPEG terminology, I-frames) are decoded without reference to any other frame in a sequence, that is, the decompresso…

Chapter 2: Format Overview / 2章:フォーマット概要

VP8

VP8 works exclusively with an 8-bit YUV 4:2:0 image format. In this format, each 8-bit pixel in the two chroma planes (U and V) corresponds positionally to a 2x2 block of 8-bit luma pixels in the Y plane; coordinates of the upper left corn…

Chapter 1: Introduction / 1章 はじめに

VP8

This document describes the VP8 compressed video data format created by Google On2, together with a discussion of the decoding procedure for this format. It is intended to be used in conjunction with and as a guide to the reference decoder…

VP8のビットストリーム仕様書を翻訳したよ(1章)

VP8

ざっくり翻訳してみたので晒してみる.こんな変な日本語読むぐらいなら,素直に英語のまま理解した方が早そうです…….でもまぁ何かの助けになれば. 仕様書よりも実装が正しいらしいw 古いMPEGとの違いは,DCT処理における厳密性で,いかなるドリフトも許容…