Sansa c200 won't play a large mpc file

[eevan]

I have a Musepack compressed CD image along with the cuesheet. It's filesize is 85 MB.
It played nicely in r17437-080510, but when I upgraded to r17518-080515, the player shows the WPS, disk access icon is constantly on and the system freezes. Today I tried with r17576-080518, but it's the same.

Smaller mpc files play ok with all builds. Also, I removed the cuesheet file and tried to play the file without it, but the problem is still there.

[Buschel]

Hi, the were quite some changes to mpc the last weeks. So here are some questions to be able to track your issue down:

1. are the files which do not play anmore sv4, sv5 or sv6 files? you can check via several tools on your pc.
2. can you track down the first version with which this happens. mpc-related changes were r17438, r17446 and only performance related r17507, r17552 and r17562.

thanks

[eevan]

Hi, thanks for reply!
I can answer to your first question immediately. All my mpc files are SV7.0

I'm downloading the builds that you specified right now. I'm willing to help you track this down

[Buschel]

ok, then r17446 is my top-candidate from what you describe -- but let's see

[eevan]

I'm unable to find exact previous builds. There are only previous daily builds, so I found 17451, installed it, and the player stucks when I try to playback the mentioned file.

[Buschel]

just to make sure: r17435 works fine?

[eevan]

I have just checked the r17435 and the file plays.

I kept r17437 as a backup. That's how I spotted the problem. Maybe that's the last build without this problem.

[Buschel]

Ok, next questions:

- what's the duration of the file (in seconds)?
- how many frames does it have?

[eevan]

Code: [Select]

File Size : 85.5MB (89 714 356 bytes)
Last Modified : 2008-05-18 19:25:58
Duration : 59:57.373 (158644164 samples)
Sample Rate : 44100 Hz
Channels : 2
Bitrate : 200 kbps
Codec : Musepack
Codec Profile : Musepack 'Standard'
Frames:  137,712
Encoding : lossy
Tool : mppenc Beta 1.16
<STREAMVERSION> : 7

[Buschel]

Perfect, thanks a lot. I think I've got an idea about where the bug may be located -- I'll give an update in this thread.

Last question for today: With your working revision -> Does seeking work fine with this file? Like seeking to 10%, 20%, 50%, 80%, 90% of the file?

[eevan]

Don't mention it
Your work is much harder. I just have to try several builds. I'm glad I was helpful.

OK. About seeking. Well, it's not working ok. Everything that follows is happening on r17437. I thought that's because of the cuesheet, so tried without it. And it goes like this: I fast forward to about 6 minutes and it finds that position and plays nicely. Then I fast forward to 13 minutes something and I hear a horrible mess for a second or so, and it continues playing from about 7 minutes. The same goes for bigger leaps. I think that it works ok if I fast forward just a few minutes.

Thanks!

[Buschel]

Hi, please try r17584. The seeking within large files should still not be possible, but it shouldnÄt crash on load.

[eevan]

Hi!
Great, it's not crashing anymore indeed!

Thanks!

[Buschel]

I am working on the seek-mechanism right now. I guess there'll be an update here soon.

EDIT:
For those of you who are able to compile rockbox: FS#9015 (http://www.rockbox.org/tracker/task/9015) contains the rework of mpc buffered seeking. With this patch seeking should be working even for large files of >28.5min duration.

EDIT2:
Rework of seek buffer submitted with r17604. Seeking within large files is possible now.

EDIT3:
Fixed some backward seeking stuff that was still not properly working with r17606.

[eevan]

I've just came from work, and downloaded the new build.
I read your commit comments and tested everything.

It works great!

The only thing I noticed is that the playback resume after power on takes quite a lot of time if the previous position was in the second half of the file, but it does not crash and finds the exact position. That isn't really an issue. In fact, it works like a charm