amcluesent;539645It's because the MP3 codec creates compressed files using fixed size blocks of data, each block give a number of ms of music.
So whenever a track is compressed by mp3, there's likely to be unused space in the last data block which then creates a gap in the playback. Some mp3 codecs like LAME add in meta-data to define how much of the data block is unused and some players can use the meta data to ignore the blank data. [/QUOTE Wrote: > > > Yeah, I've read about this problem. But an mp3 frame, as I understand > it, is only a few hundredths of a second, and any gap introduced to > fill it out will be a fraction of that. I understand that such gaps are > audible, but they're not the ones I would be worried about. > > This came up for me when I downloaded an mp3 of the Richard Harris > album "A Tramp Shining," and I noticed that some of the songs are > divided into two tracks. For example, the first song, "Didn't We," is > track 2, track 1 being a "Prelude" that lasts only about 30 seconds. > But that's not the way it is on the audio CD, at least not the one > available in the U.S. On the CD, there's just a single track for > "Didn't We" that obviously (from the timing) includes the prelude. So I > was worried that the division of the song into two tracks might mean > that my playback of the album I downloaded might introduce a pause in > the middle of the song that wasn't present on the original album. > > One thing I've learned from this discussion is that I don't have to > worry about this. The gap between tracks introduced by the CD "pregap" > is always at least 2 seconds by design, which rippers mimic by adding > periods of silence to the beginnnings and ends of the tracks. If the > pregap isn't used, then the ripper won't add any silence. Playback > systems don't add any delays of their own, they play tracks > sequentially without gaps. The result is that the structure of the CD > is reproduced pretty well, albeit with the occasional audible gap of 10 > ms or so when older, lossy file formats are used. > > In the case above, the album might have been ripped from a version of > the CD (the likeliest case, I think), or the files might have been > divided by somebody. But either way, there shouldn't be any space added > that wasn't there originally. > > It's surprising to me that I haven't been able to find an "idiot's > guide" to these issues on the Web somewhere. There's plenty on how to > avoid gaps when buring CDs, but very little on gaps when ripping. -- dpotts ------------------------------------------------------------------------ dpotts's Profile: http://forums.slimdevices.com/member.php?userid=29782 View this thread: http://forums.slimdevices.com/showthread.php?t=77714 _______________________________________________ ripping mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/ripping
