Hi! Inspired by the discussion about mixing Vorbis streams and so on I came to the question whether Vorbisstreams can be, just like MP3, reencoded without further loss. As I heard, and I am pretty sure that it's true, MP3 files can be decoded and reencoded unlimited times without further quality loss (of course the same encoder with the same preferences has to be used all the time). Is this also possible with .OGG? Thanks, Moritz --- >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 'vorbis-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.
Moritz Grimm wrote:> > Hi! > > Inspired by the discussion about mixing Vorbis streams and so on I came > to the question whether Vorbisstreams can be, just like MP3, reencoded > without further loss. > > As I heard, and I am pretty sure that it's true, MP3 files can be > decoded and reencoded unlimited times without further quality loss (of > course the same encoder with the same preferences has to be used all the > time). Is this also possible with .OGG?No, but not with mp3, either. With most mp3 encoders, a file that has been 10 to 20 times recoded sounds very bad. Cheers, Segher --- >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 'vorbis-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.
On Wed, Feb 21, 2001 at 08:15:01AM +0100, Moritz Grimm wrote:> Inspired by the discussion about mixing Vorbis streams and so on I came > to the question whether Vorbisstreams can be, just like MP3, reencoded > without further loss. > > As I heard, and I am pretty sure that it's true, MP3 files can be > decoded and reencoded unlimited times without further quality loss (of > course the same encoder with the same preferences has to be used all the > time). Is this also possible with .OGG?I'd like to see the mp3 encoder which does this. In prior expirments I found that all the mp3 encoders I could find would eventually reach a almost steady-state output after many encode-decode cycles, but the output sounded much worse then the first generation. In a simmlar test, Vorbis faired much better. However, there are many decisions made based on the content of the audio (window switching, floor shape, etc) so it's unlikely that 'lossless' reencoding is possible with the current encoder. However, in actual tests, vorbis fairs well.. I ran audio through a number of encode/decode cycles (I believe 50) and ended up with something that sounded just like the orignal on a quick surface listening. --- >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 'vorbis-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.
>As I heard, and I am pretty sure that it's true, MP3 files can be >decoded and reencoded unlimited times without further quality loss (of >course the same encoder with the same preferences has to be used all the >time). Is this also possible with .OGG? >Nope, this definately isn't possible with vorbis. It ALSO isn't possible with mp3, though. Michael --- >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 'vorbis-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.