案例库 · 工程与运营 · 技术决策 · 1998-2020s
这条还没译成中文,下面是英文原文。
H.264 won video by halving MPEG-2's bitrate and shipping in hardware
H.264/AVC matched MPEG-2 quality at half the bitrate, and once it was built into Blu-ray and phone hardware it became the universal video codec.
ITU-T / ISO/IEC (MPEG)
那一手
Video compression needed to get smaller as screens grew. MPEG-2, standardized in 1993, was the foundation of DVD and broadcast, but HD video on it needed 15-20Mbps, which was heavy for broadband and discs. In 2003, the AVC/H.264 spec became a standard.
H.264's defining advantage was efficiency: it achieved the same video quality as MPEG-2 at about half the bitrate, allowing better HD at lower cost. That made it the ideal fit for Blu-ray, which adopted it as one of its mandatory video compression formats, as well as for the fast-growing world of online video.
When it was first standardized, H.264 was said to be too complex and difficult to embed in hardware. Over time the complexity became a non-issue as decoding moved into dedicated LSIs and IP cores, so a low-cost chip could handle it in phones, cameras and players.
The result was convergence. Because virtually every Blu-ray player, smartphone and HD device shipped with H.264 decoding built in, it became the common video format across disc, broadcast and the web — the codec chosen not just for quality but because it was already in the hardware everyone owned.
为什么管用
- Half the bitrate at the same quality justified a jump from MPEG-2
- Blu-ray made H.264 a mandatory video format, guaranteeing a market
- Hardware decoding removed the performance burden critics feared
- One codec in devices, discs and streaming created network effects
可以搬走什么
An audio-visual standard wins not only by being good but by being the one delivered in the dominant hardware of the moment, so adoption stops being a choice and becomes the default.
后来呢
H.264/AVC became the most widely used compressed video format, running Blu-ray, broadcast, mobile video and nearly all online video. MPEG LA's patent pool licensed the essential patents, with hundreds of companies signing on, so the commercial terms were workable. The standard held for well over a decade before HEVC/H.265 and then open codecs like AV1 began to take over for higher resolutions, but H.264 remained the default baseline for playback everywhere.
资料来源
- Commentary: H.264 Video — The Format of Convergence
- Inter BEE 2014 Report 2: A Wealth of Encoding Technologies
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