问题描述
从配置文件中识别h264配置文件和级别sdp中的-level-id?
如何识别约束的实际含义?例如，我有一个profile-type-id: 42801e可以翻译为:
How does one identify what the constraints actually mean?For example I have a profile-type-id: 42801e that translates to:
如何将其与表在这里?
以上参考资料表明Constraint_set0_flag: 1表示它是受约束的基线配置文件.但是，如何将标志与()区分基准配置文件和约束基准配置文件的三个不同的否相关?
The above reference identified that the Constraint_set0_flag: 1 means that it's the Constrained Baseline Profile. But how to relate the flag to the three different NO's (from the table) that differentiate the Baseline profile from the Constrained Baseline Profile?
更新
无法确认上述有关识别Constrained Baseline profile的信息是正确的. 参考(第306页):
Can't confirm that the above, about identifying the Constrained Baseline profile, is correct. Reference (page 306) for that statement:
Decoders conforming to the Constrained Baseline profile at a
specific level shall be capable of decoding all bitstreams
in which all of the following are true:
– profile_idc is equal to 66 or constraint_set0_flag is equal to 1,
– constraint_set1_flag is equal to 1,
– level_idc and constraint_set3_flag represent a level
less than or equal to the specified level.
似乎只有第一个条件得到满足，但第二个条件是错误的.基准资料状态的参数
It seems only the first condition is fulfilled but the second is false. The parameters for the Baseline profile state
它们都存在.
推荐答案
您能澄清您的问题吗?你到底不明白什么?您已经将42801e解析为受约束的基准配置文件级别3.0".
Can you clarify your question? What exactly don't you understand? You have already parsed 42801e as Constrained Baseline Profile Level 3.0.
由constraint_set0_flag = 1标识的受约束的基线"配置文件意味着编码流不使用此配置文件之外的任何功能(例如Wikipedia表中的FMO或ASO)，因此可以使用任何支持受约束的基线"的解码器进行解码，主配置文件或高级配置文件.使用Baseline Profile(不受约束)Profile编码的流可以使用此附加功能(或不使用，但仍未指示为Constrained)，但是如果将其用于流中，则比仅支持Constrained Baseline，Main或High Profile的解码器将不支持能够对其进行解码.
Constrained Baseline Profile identified by constraint_set0_flag=1 mean that encoded stream don't use any of the features outside of this profile (like FMO or ASO from wikipedia table) and so can be decoded with any decoder with support of Constrained Baseline, Main or High profiles. Streams encoded with Baseline Profile (not Constrained) Profile can use this additional features (or not use but still not be indicated as Constrained) but if they will be used in stream than decoders which support only Constrained Baseline, Main or High profiles wouldn't be able to decode it.
更新
我错了.这是基准配置文件级别3.0，因为constraint_set1_flag = 0，因此没有任何受约束的基准配置文件的指示.
I was wrong. It is Baseline Profile Level 3.0 because constraint_set1_flag=0 and so there is no indication of Constrained Baseline Profile.
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