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24 lines
1.3 KiB
Text
24 lines
1.3 KiB
Text
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notes for encoders
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====
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two types of encoders:
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1) File encoders. These write directly to a file.
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2) Stream encoders. These return the encoded audio data in a user-provided buffer
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For example, an AAC encoder could implement a file encoder for MP4/M4A files, but these aren't streamable.
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ADTS AAC however, would be streamable.
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====
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Two ways of feeding the data
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1) Push model. The user of the class passes data in a user-owned data buffer.
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2) Pull model. The implementor of the class pulls data from a user-provided callback (data is stored in an implementor-owned buffer)
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Push encoders should be used when the incoming audio data is not immediately available (live recording, CD ripping).
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Pull encoders should only be used when all the audio data is immediately available (e.g. WAV file).
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When in doubt, use a push encoder. Pull encoders offer a potential advantage of better memory usage (fewer memcpy's in most implementations), but a push encoder should serve all needs.
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====
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Note that encoders should be as non-blocking as possible (except for, obviously, computation, file I/O and thread synchronization for multi-core-aware encoders).
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It it not reommended to Sleep(), select() [network I/O], etc. Stick to what the API was designed for :)
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