Hi, I'm about finished developing a QuickTime component that supports Speex (on MacOS X and Windows).. As it is now the user can set complexity (SPEEX_SET_COMPLEXITY) and quality (SPEEX_SET_QUALITY / SPEEX_SET_VBR_QUALITY) and to wether to use VBR or not. Will these options make it possible to produce all combinations of bitrates/qualities? Or should I also use SPEEX_SET_MODE/SPEEX_SET_LOW_MODE/SPEEX_SET_HIGH_MODE to accomplish this? /Pontus --- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/ To unsubscribe from this list, send a message to 'speex-dev-request@xiph.org' containing only the word 'unsubscribe' in the body. No subject is needed. Unsubscribe messages sent to the list will be ignored/filtered.
> I'm about finished developing a QuickTime component that supports Speex > (on > MacOS X and Windows).. As it is now the user can set complexity > (SPEEX_SET_COMPLEXITY) and quality (SPEEX_SET_QUALITY / > SPEEX_SET_VBR_QUALITY) and to wether to use VBR or not. Will these > options > make it possible to produce all combinations of bitrates/qualities? Or > should I also use SPEEX_SET_MODE/SPEEX_SET_LOW_MODE/SPEEX_SET_HIGH_MODE > to > accomplish this?The first thing to know that setting quality from 0-10 is in fact a more user-friendly of setting the mode. That being said, for narrowband encoding, all modes are available with at least one quality setting (sometimes two quality settings point to the same mode because there are less than 10 modes). For wideband encoding, not all possible mode combination (one mode for the low-band, one for the high-band) are available with the 10 quality settings, but those that aren't available are mostly useless anyway (e.g. a combination that gives you very good quality above 4 kHz, but very poor below that is useless). In most cases I would suggest not making the modes directly available, unless maybe for "expert users". The only other place where it can be useful is that modes have a specific bit-rate/quality associated to them, while the mapping between the "quality settings" and the modes are not guarantied to remain the same in the future. That being said, you probably better keep what you have now. Hope this helps. Jean-Marc -- Jean-Marc Valin, M.Sc.A. LABORIUS (http://www.gel.usherb.ca/laborius) Université de Sherbrooke, Québec, Canada -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 242 bytes Desc: signature.asc Url : http://lists.xiph.org/pipermail/speex-dev/attachments/20021012/503e03f5/signature.pgp
Thanks! Btw, have you tried using SBR-technology or similar with speech codecs? That might be a good idea I thought.. But I don't know if it produces as good quality with speech codecs as it does for music codecs. Do you know if there is any open source variant of SBR? /Pontus -----Ursprungligt meddelande----- Från: owner-speex-dev@xiph.org [mailto:owner-speex-dev@xiph.org]För Jean-Marc Valin Skickat: den 13 oktober 2002 05:57 Till: speex Ämne: Re: [speex-dev] Speex modes <p>> I'm about finished developing a QuickTime component that supports Speex> (on > MacOS X and Windows).. As it is now the user can set complexity > (SPEEX_SET_COMPLEXITY) and quality (SPEEX_SET_QUALITY / > SPEEX_SET_VBR_QUALITY) and to wether to use VBR or not. Will these > options > make it possible to produce all combinations of bitrates/qualities? Or > should I also use SPEEX_SET_MODE/SPEEX_SET_LOW_MODE/SPEEX_SET_HIGH_MODE > to > accomplish this?The first thing to know that setting quality from 0-10 is in fact a more user-friendly of setting the mode. That being said, for narrowband encoding, all modes are available with at least one quality setting (sometimes two quality settings point to the same mode because there are less than 10 modes). For wideband encoding, not all possible mode combination (one mode for the low-band, one for the high-band) are available with the 10 quality settings, but those that aren't available are mostly useless anyway (e.g. a combination that gives you very good quality above 4 kHz, but very poor below that is useless). In most cases I would suggest not making the modes directly available, unless maybe for "expert users". The only other place where it can be useful is that modes have a specific bit-rate/quality associated to them, while the mapping between the "quality settings" and the modes are not guarantied to remain the same in the future. That being said, you probably better keep what you have now. Hope this helps. Jean-Marc -- Jean-Marc Valin, M.Sc.A. LABORIUS (http://www.gel.usherb.ca/laborius) Université de Sherbrooke, Québec, Canada <p>--- >8 ---- List archives: http://www.xiph.org/archives/ Ogg project homepage: http://www.xiph.org/ogg/ To unsubscribe from this list, send a message to 'speex-dev-request@xiph.org' containing only the word 'unsubscribe' in the body. No subject is needed. Unsubscribe messages sent to the list will be ignored/filtered.