iPod Video crossfade causes hang when changing CODEC?

[Pond]

Can't find other mentions of this so wanted to check here before submitting a bug on the tracker.

I have an 80GB iPod Video with RockBox r15915-071213. It has about 13K songs on, the majority in Q2.5 Vorbis and some at <= 128kbps CBR MP3. Crossfading works well between MP3 tracks or between Vorbis tracks, but glitches badly if trying to fade between Vorbis and MP3. This is with crossfade mode "Crossfade" - I've not tried "Mix". With longer crossfade times, there's a high chance that the player will just hang altogether and need rebooting.

Even with crossfading turned off, I note that track skipping between Vorbis and MP3 items can be very time consuming and problematic too. Is the player having to do a lot of work to switch decoder code into place, say?

Possibly related:

  http://forums.rockbox.org/index.php?topic=13926.0

Can anyone else replicate the problem?

BTW, I tried Rockbox some time ago and found it barely usable on an older iPod, with frequent crashes - but it wasn't designated as 'stable' on iPod then. There are still gitches, but things are overall immeasurably better now; thanks to all contributors for your ongoing hard work

[LambdaCalculus]

I tried Rockbox some time ago and found it barely usable on an older iPod, with frequent crashes - but it wasn't designated as 'stable' on iPod then. There are still gitches, but things are overall immeasurably better now; thanks to all contributors for your ongoing hard work

December 28th will be my first year anniversary of using Rockbox... damn, how time flies and things change.

As for your crossfading problem, I haven't really seen this happen between Vorbis and MP3, at least not on my end. My Vorbis files are Q5, and my MP3s are usually high-rate VBR. What did you use to create the files, out of curiousity?

[Pond]

What did you use to create the files, out of curiousity?

The overwhelming majority of the Vorbis files were converted from FLAC source to Vorbis copy with an OggDropXPD build incorporating the aoTuV tweaked encoder on a Win32 platform.

For material that's sourced in MP3 format at or below 128kbps, the files already small and further lossy encoding on such a poor quality source would be a really bad idea, so I use those directly. As a result, the encoding software can be just about anything. I've had a look at a few of the MP3s and see no common pattern. The iPod just can't seem to reliably crossfade from Vorbis to MP3 or back.

I wonder if this is just a quirk of my particular current daily build.

[LambdaCalculus]

Try updating, but keep a copy of r15915 on hand so you can see if it still occurs.

Also, try some builds between 15915 and now (r15948), so you can zero in on where exactly it was fixed, if at all.

[Pond]

OK, I'll try to find time for this in the next day or two and post back. Thanks for the prompt response.

[Pond]

Hmmm... I ran a clean build downloaded a few minutes ago, changing only the default settings to turn on crossfade and set a 5 second fade in and out time. I could not provoke any faults. I returned to the original firmware with the same playlist - fault shows up. So I copied the newer firmware data over the old firmware (always a dodgy move, but I was feeling adventurous) and it boots fine, showing the new build version, but still glitches during crossfades.

Clearly, more investigation (on my part) is required.

[Llorean]

Please use the "Modify" button as clearly stated in the Guidelines you are required to do when nobody has responded.

[Pond]

Please use the "Modify" button as clearly stated in the Guidelines you are required to do when nobody has responded.

Apologies; I thought that I was clearly adding new information. Since my message stated that I believe I have further work to do myself, I didn't see it as some kind of malicious "bump" attempt (and am surprised that it seems to have been construed as such). Specifically, I thought I was acting under the phrase "That wasn't a bump, I honestly had more to say", from your own message as the last entry in this thread:

  http://forums.rockbox.org/index.php?topic=13864.0

Sorry for the misunderstanding. I'll use "modify" in future, even though (to me personally, based on rules of other forums) it feels rather unnatural to do so in this context.

[Llorean]

If you read that full post that you've linked, I said clearly "there is no objective way to know whether something is 'I had more to say' vs 'I found more to say as a means of bumping'". It's not that it "seems like a bump" as "it doesn't matter whether it seems like a bump, we ask that you always edit if nobody has responded." Is this unclear in the actual guidelines? (The post you linked is merely a discussion of them, and still says what I said here.)

If you honestly add more information, do it in an edit. The rules are not unclear on this, they don't say "unless it's honestly new information."

It may feel unnatural to you, but we ask very strongly that you abide by our rules while posting in our forums. Edited posts still show up as "new" so people taking an interest can still see things have changed, while preventing any argument over whether anything was a bump or not.

[Pond]

If you read that full post that you've linked, I said clearly "there is no objective way to know whether something is 'I had more to say' vs 'I found more to say as a means of bumping'". It's not that it "seems like a bump" as "it doesn't matter whether it seems like a bump, we ask that you always edit if nobody has responded." Is this unclear in the actual guidelines? (The post you linked is merely a discussion of them, and still says what I said here.)

I think this is where the confusion arises - I'm not trying to be difficult, honest! As I said earlier, I'll definitely follow this forum's rules. But I still can't see the "no objective way..." quote you give above in that thread to which I linked. You go on to say that the thread is "merely a discussion of them" (the guidelines), so I'm reading the wrong thing entirely, I suspect.

Sorry to continue to take up your time on this, but please could you point me at the right thread (e.g. private message if you prefer not to perpetuate this topic)? I can't find any post relating to actual guidelines except for the thread at http://forums.rockbox.org/index.php?topic=13864.0 which seems to discuss guidelines, containing 5 messages, but does not actually lay any guidelines down.

Ultimately a single sticky thread that says "rules are 'foo'" would be useful for dim people like me who can't quite figure out what's going on, because everyone else seems to already know and nobody has listed the rules explicitly.

[Llorean]

http://forums.rockbox.org/index.php?board=38.0 <-- Look at the first thread here...

[cool_walking_]

http://forums.rockbox.org/index.php?board=38.0 <-- Look at the first thread here...

It might be a good idea to duplicate this in the other forums, or better yet, put a link to it in the "POSTING IN THIS FORUM" threads.

[Pond]

It might be a good idea to duplicate this in the other forums, or better yet, put a link to it in the "POSTING IN THIS FORUM" threads.

That would be useful, but thanks, Llorean, for pointing me in the right direction. I'll read through it carefully.

Have a good Christmas, all.

[EDIT, 25-Jan-2008] Following on from the original problem...

I've not got anywhere with the crossfade hang, due to being generally more distracted by the problems I mentioned with skipping tracks. It all sounds very like the following bug:

http://www.rockbox.org/tracker/task/8397?histring=ipod