What is Gapless playback?

tamalet · Post by **tamalet** » Wed Oct 20, 2010 8:41 am

I tried again at my desktop.

Test 1: I enabled the silence detector. "Only in the last 45 seconds" was enabled but I disabled it. I played Something in the Way. Guayadeque plays like 2 minutes of silence and 45 seconds before the end it moves to the next track.

Test 2: I restart Guayadeque, play the song, it plays until the end with all the silence then it skips the next songs as described above. It was actually worse because I had smart mode on. It would play a few seconds of a song and it will continue skipping and adding more songs.

Test 3: restart again, play the song. After a few seconds of silence it skips the rest of the tracks.

Test 4: as Test 3.

Note from Test 2 on I manually move the track slider to save time and to not get bored of the same song

anonbeat · Post by **anonbeat** » Wed Oct 20, 2010 1:35 pm

What level had you configured ?
WHen you remove the time limit option does the new tracks get the signal over the thresold you have configure ? if no its normal that the tracks skip

Please let me know

Thanks for your help

anonbeat · Post by **anonbeat** » Wed Oct 20, 2010 1:44 pm

Also I want to explain that the level checked is not the instantaneous one but the decay one. The one you see in the Vumeters as a single line fading all the time. This is to prevent lower levels from short times to triger the skip.

tamalet · Post by **tamalet** » Thu Oct 21, 2010 3:53 am

On my desktop it was at the default, -50.
I had to disable it because at some point a few times when a song started it was skipped.
On my notebook, during the testing I moved to -55.

anonbeat, does my suggestion about "hidden tracks" make sense to you?

rotwang888 · Post by **rotwang888** » Thu Oct 21, 2010 10:50 am

Wow, this thread got really long before I found it. If you're still collecting opinions, I have one. Gapless playback (even if the name could be misleading) should be no gap between tracks. If there is continuous sound from one track to the next, the sound should be continuous. If there is 3 seconds of silence at the end of the track, it should be saved, and if there is a hidden track with 20 minutes of silence at the beginning, it should play 20 minutes of silence. Anything that automatically removes silence or jumps to some point in a track should be optional and not enabled by default.

camaron · Post by **camaron** » Thu Oct 21, 2010 11:00 am

rotwang888 wrote:Wow, this thread got really long before I found it. If you're still collecting opinions, I have one. Gapless playback (even if the name could be misleading) should be no gap between tracks. If there is continuous sound from one track to the next, the sound should be continuous. If there is 3 seconds of silence at the end of the track, it should be saved, and if there is a hidden track with 20 minutes of silence at the beginning, it should play 20 minutes of silence. Anything that automatically removes silence or jumps to some point in a track should be optional and not enabled by default.

Given the overwhelming support for this interpretation it is obvious that I was plain wrong.
The issue came about when writing up documentation for Guayadeque. As you have just explained it Guayadeque does provide proper gapless playback and this will be reflected/ explain in the documentation. (by the way the documentation also will explain how to play improper gapless playback....)

genesys87 · Post by **genesys87** » Fri Dec 24, 2010 11:31 am

camaron, a note on gapless playback: mp3 format doesn't have gapless support built in*, so in general mp3 files will never be gapless (ie: you'll always hear a glitch between tracks); this problem can be circumvent encoding a bunch of mp3 files with lame using the option --nogap (the player must obviously support this tag**).
wav files don't suffer this problem because they're not compressed; ogg format is built properly to avoid this problem.

* gapless problem result from two factor: 1) the player close and reopen the audiostream after each song (nowadays I think every player don't do it anymore, they use buffer to avoid it); 2) mp3 has frames of fixed length, so at the beginning an at the end there is always a little silence inserted by the encoder to pad the frame to the correct length

** the --nogap option insert a tag in the mp3 that says the length of silence inserted by the encoder in the beginning and ending frames.

camaron · Post by **camaron** » Fri Dec 24, 2010 12:14 pm

Interesting genesys: you just gave me one more reason to stick to flac. It is true that I've heard other people complain before about that glitch with mp3.
This is something by the way which I can't quite understand: with the ever-increasing storage capabilities for digital media why people compromise in sound quality? But that's a different topic....