[vorbis] vbr / cbr / abr API calls

[Akos Maroy]

Hi,

Maybe this is documented somewhere, if so, please send me a link to the 
documentation.

My question is: how to set up different (VBR, CBR, ABR) modes when 
calling the Ogg Vorbis API?

Currently I do:

CBR:

     ret = vorbis_encode_setup_managed( &vorbisInfo,
                                        getInChannel(),
                                        getOutSampleRate(),
                                        -1,
                                        getOutBitrate() * 1000,
                                        -1)
        || vorbis_encode_ctl( &vorbisInfo, OV_ECTL_RATEMANAGE_AVG, NULL)
        || vorbis_encode_setup_init( &vorbisInfo);

<p>ABR:

     ret = vorbis_encode_init( &vorbisInfo,
                               getInChannel(),
                               getOutSampleRate(),
                               -1,
                               getOutBitrate() * 1000,
                               -1 );

VBR:

     ret = vorbis_encode_init_vbr( &vorbisInfo,
                                   getInChannel(),
                                   getOutSampleRate(),
                                   getOutQuality() );

<p>Are these calls correct?

What effect do the max_bitrate, min_bitrate parameters have in the CBR 
and ABR modes?

When measuring performance, it seems that the ABR mode takes a lot more 
(about twice) processing power than VBR of even CBR. why is that?

Thanks,

<p>Akos

<p><p>--- >8 ----
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