When is a "corrupted" .ts file NOT?

[htewam]

I am using Gbpvr 1.3.11 configured with an HVR-1600 (Digital) capture card to record from Comcast with Clear QAM channels.

Because I am a MVP user, I have been using ffmpeg to transcode from the recorded .ts files over to .mpg. For 20+ channels, this set up seems to work (although I haven't yet fine-tuned the transcode options available through ffmpeg).

However, on about 5 of these clear QAM channels (and only these specific channels), I end up with a transcoded .mpg file that has audio but no video. Investigating further:
- If I simply try to play back the resulting .ts file under gbpvr (on the PC), the .ts file looks just fine (both audio and video) -- so the built-in .ts reader seems to like the format of the recorded file
- When I examine the ffmpeg log (during transcoding), I see lots of errors
- When I simply try to "read" the .ts file (e.g. Ffmpeg -y -I "my_ts_file.ts") yields the following message:
my_ts_file.ts: I/O error occurred
Usually that means that input file is truncated and/or corrupted.

Are there some additional switches that need to be set for ffmpeg to make sense out of these "special" .ts files? ffmpeg doesn't seem to have any problem reading the .ts files recorded for the other channels.

I took a brief look at the gbpvr/logs but (at first glance) didn't see anything different about these specific channels vs all of the other digital clear QAM channels.

Thanks in advance.

[htewam]

Belatedly, I just took a new look through support and saw this thread which seems to be related: http://forums.nextpvr.com/showthread.php?t=43146

But my situation seems a bit different because I just set up the channels about 5 days ago, I can use the "digital mapping" preview window in config and I can see the correct channel, and I can view it with Live TV... I just can't seem to transcode the recorded .ts.

[sub]

I think its probably just a case of ffmpeg not liking something that the broadcaster is doing in the encoding of these channels. There isnt a GB-PVR setting that is likely to affect this, but you might find that updating the version of ffmpeg helps.

[htewam]

Thanks sub. I downloaded the most recent ffmpeg and that version no longer reports the .ts as corrupted... my initial playing with it now gets me the video but no audio... but I will continue to play with the settings.

One thing that surprised me was that the ffmpeg in the gbpvr/Third Party had a copyright of 2006 (I didn't have time to jot down the version info)... this seems like a pretty old version (ffmpeg seems to get lots of updates).

Anyway... this gives me a starting point.

[zehd]

Thanks sub. I downloaded the most recent ffmpeg and that version no longer reports the .ts as corrupted... my initial playing with it now gets me the video but no audio... but I will continue to play with the settings.

One thing that surprised me was that the ffmpeg in the gbpvr/Third Party had a copyright of 2006 (I didn't have time to jot down the version info)... this seems like a pretty old version (ffmpeg seems to get lots of updates).

Anyway... this gives me a starting point.

Yep, the version that ships with GB-PVR hasn't changed in a long time. Mostly, working out just fine. Switching to newer and newer versions can cause a lot of trouble, because programs, (especially ffmpeg) don't adhere to backward compatibility all that well.

A version of FFmpeg that I've been playing with is 0.5. It's quite good, handling most of the newer files and codecs. There was some talk about upgrading the version that ship with GB-PVR on the next release, but that may not be a priority.

[sub]

Yeah thats pretty much the case. If I was updated ffmpeg each release, then I'm going to need to spend alot of time testing that stuff. The reality is that I dont have that time available, and ffmpeg is used for stuff in GB-PVR that I'm generally not interested in.

As Zehd mention, I have talked about updating it recently, but I havnt done anything about that yet.