Timing temporarily off with playback 25% and timestretch

[bokkiej]

When syncing the notes to the music, I like to use playback rate of 25% and timestretch. This makes it easier to spot desync. However, when I'm working, sometimes the music isn't synced with playback. For instance, when I have added a leading silence, music still plays from the beginning. This isn't on playback rate 100%, seems to be random (so I can't tell how to reproduce), still occurs after pausing, and rewinding sometimes seems to solve the issue (maybe even always, not sure).

 

At first I thought I was crazy but then it happened while the music clearly wasn't in sync with the waveform graph, so it really seems to be a bug.

 

Using r1306.

 

(Next to that, I have to applaud you for your efforts! :))

[raynebc]

I tested it out on my computer just to make sure it wasn't a problem with leading silence, and when I added a measure of silence, the time stretch playback still was synced to the adjusted chart.

 

The time stretch playback is a lot more processor intensive than normal playback. It's possible that it's causing EOF to lag during playback, so it may lose sync with the graphics until you seek or pause and resume playback. My development computer is kind of low powered compared to my lab computer that I use for fun stuff like playing Rocksmith PC, emulating Wii games, doing video capture, etc, so depending on what other programs I have running, it can cause EOF to lag. Some things will cause more lag than others, ie. having Audacity open seems to cause extra CPU cycles to be drained on my computer. You could try going into Task Manager and giving EOF "above normal" process priority (go to processes tab, find eof.exe, right click on it, select Set Priority and change the priority from normal). If you have a multi-core processor, EOF only has one thread so it can only use up to one core, so increasing the priority may be the best thing you can do to help it. It's best not to give it any higher than "above normal" priority though, in case EOF hangs it could make the rest of your computer less responsive until you terminate EOF.

[bokkiej]

Will try! I do have a 'fairly decent' i5-3570k though so if I have this problem, probably more people have it. I'll look into cpu utilization later on :)

[Tmlt]

I have noticed this too, but figured it was a problem with my somewhat crappy gfx card. Will try the "above normal" priority thingy

[MVega]

I had this problem this morning, but it went away when I stopped playback, repositioned the cursor and restarted it.

 

I have a feeling the loss of sync happened because I didn't wait long enough before hitting the spacebar, as if it takes a second or two for EOF to calculate the new speed (Note: I work on an old -- 8 years? -- computer running XP, which may account for that lag.)

[raynebc]

Only the first time stretched playback for an editing session of a project will take a couple seconds to process the song. Subsequent time stretched playbacks should start without delay, but as mentioned it can cause your computer to lag. I've tried this on multiple fast computers and it stayed pretty much perfectly synced even when I changed speed during playback.

[bokkiej]

Hooray, I´m able to reproduce it! Problem doesn´t seem to be high cpu usage. It stays below 60% for the used CPU (I'm not reporting total CPU usage! Because that would factor in other cores but you said it doesn't use them so that wouldn't give useful results) and and also isn´t affected by changing priority to above normal.

 

Open notes.eof, press F5, change playback rate to 25%, zoom to 1/1, play from the beginning, rewind with arrow or rewind button in GUI to before first notes, it automatically keeps on playing and notice: music is played about .15 seconds before it should according to the waveform graph. At least, it is on my pc ;). 

 

Files can be found here, music files included.

 

EoF r1308 used.

[raynebc]

I wasn't able to reproduce this on my lab computer. My development computer is slower and the reason it desynces is because of lag. Results may vary from one computer to the next.