H264/AVC视频解码时AVC1和H264的区别

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我一直疑问为什么有些视频解码时显示格式是:H264，大部分又是：AVC1
0 o7 f/ e1 _, |7 x) D5 s; Q" I我在搜索编程资料时在微软的msdn上发现的：
( I$ f9 H( |  t+ T 原文:http://msdn.microsoft.com/en-us/library/dd757808(v=vs.85).aspx
) G- w9 M% O' R. D/ {. q FOURCC:AVC1 描述:H.264 bitstream without start codes.
$ H! z* l' g4 d* H" B8 J6 b/ V FOURCC:H264 描述:H.264 bitstream with start codes.
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H.264 Bitstream with Start Codes
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H.264 bitstreams that are transmitted over the air, or contained in MPEG-2 program or transport streams, or recorded on HD-DVD, are formatted as described in Annex B of ITU-T Rec. H.264. According to this specification, the bitstream consists of a sequence of network abstraction layer units (NALUs), each of which is prefixed with a start code equal to 0x000001 or 0x00000001.
, V+ |9 _" Q' T  Y  J* I这段话的大致意思是：带有开始码的H.264视频一般是用于无线发射、有线广播或者HD-DVD中的。这些数据流的开始都有一个开始码：0x000001 或者 0x00000001.
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H.264 Bitstream Without Start Codes

+ `3 M! w" `. `3 B4 \9 j The MP4 container format stores H.264 data without start codes. Instead, each NALU is prefixed by a length field, which gives the length of the NALU in bytes. The size of the length field can vary, but is typically 1, 2, or 4 bytes.
这段话的大致意思是：没有开始码的H.264视频主要是存储在MP4格式的文件中的。它的数据流的开始是1、2或者4个字节表示长度数据。
: m4 Q8 V0 f. G+ r; ]原文中的"NALU"简单说是H.264格式中的最基本的单元，是一个数据包。
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