Speex dev - Mar 2005 - speex and single frame decompression

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Hi,

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I've started thinking about speex and speex stream. I wonder to know if
speex can do this:

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Let assume we already have PCM stream encoded with speex (e.g. saved in a
file or memowy):

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frame1 | frame 2 | frame 3 | frame 4 | ... | frame N-1 | frame N,

where frame n is a single (20 ms) speex frame.

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Now we decompress only a part of that stream, let say (3 frames):

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frame 2, frame 3, frame 4? -> pcm_frame_2, pcm_frame_3, pcm_frame_4,

where pcm_frame_n?is a pcm format signal generated by decoding n-th speex
frame

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and then

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decompress another path od the same encoded stream:

frame 1, frame 2, frame?3, frame 4? -> pcm_frame_1', pcm_frame_2',
pcm_frame_3', pmc_frame_4',

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Question: pcm_frame_2?? ???? pcm_frame_2'?? will by identical?

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I thik, above quiestion coul'd be simplified to: "is speex
stateless?"

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Regards

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Janek

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> I thik, above quiestion coul'd be simplified to: "is speex
stateless?"
Speex is *not* stateless. The same applies to all CELP codecs.

	Jean-Marc

-- 
Jean-Marc Valin <Jean-Marc.Valin@USherbrooke.ca>
Universit? de Sherbrooke

Jean-Marc Valin wrote:
>>I thik, above quiestion coul'd be simplified to: "is speex
stateless?"
>>    
>>
>
>Speex is *not* stateless. The same applies to all CELP codecs.
>
>	Jean-Marc
>
>  
>
What about iLBC? I think that is an exception. Its the only one I can 
think of, though, and it pays dearly in bit rate for being stateless.

Regards,
Steve