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SomeJoe
11th September 2009, 05:13
Neuron2,

I have an MPEG-2 elementary stream that I am unable to automatically index with DGIndex. This stream is from a commercial DVD (which I own). When attempting to load the .m2v into DGIndex, I get the following error:

"Cannot find audio or video data. Ensure that your PIDs are set correctly in the Stream menu. Refer to the Users Manual for details."

The stream is an MPEG-2 elementary stream (.m2v) straight off the DVD (extracted with DVDDecrypter in demux mode), not a transport stream, so as I understand it, PIDs should not be an issue. If you try Detect PIDs: PAT/PMT, it tells you it could not find any PAT/PMT tables. If you try Detect PIDs: PSIP, it tells you it could not find any PSIP tables. However, if you do "Detect PIDs: Raw", you get a list about a mile long of meaningless PIDs. One of them is 0x15 (21), which appears to be the correct PID, and selecting that and doing Set Video actually allows it to work. Windows Media Player will actually play this file, and there appears to be nothing wrong with the DVD, so I'm at a loss as to why DGIndex is unable to do this automatically.

I have attempted to cut a segment of this MPEG-2 using DGSplit (tried both a 50MB and a 100MB chunk), but when I load these into DGIndex, I don't get an error (although it still will not play or decode any video). Even more strange, attempting to select PID 0x15 (21) like I did above results in the error:

File contains all nulls!

I finally tried a 250MB chunk, and that now seems to trigger behavior identical to the original .m2v (4GB) -- an error message regarding PIDs, and then manual selection of PID 0x15 (21) allows video decoding.

I can only assume that this MPEG-2 stream is wildly odd for the first few hundred MB until there is some structure later on in the file that DGIndex finally recognizes enough to begin to decode video.

I will PM you a link where you can download the 250MB chunk. I didn't want to post this link in the open forum.

neuron2
11th September 2009, 21:04
It was a slow download but I have it now. But I can't look at it until this evening. Please standby...

EDIT: Found the cause. Unusual picture data emulating transport sync bytes. Will release a fix this evening.

neuron2
12th September 2009, 00:44
Here's a fixed version of DGIndex:

http://neuron2.net/dgmpgdec/dgindex156b3.zip

SomeJoe
12th September 2009, 05:27
:thanks:

Thanks, neuron2!

Will test and post back ...

(By the way, I think the same bug exists in the DGMPGIndexNV tool ... I haven't tried the latest Beta9, but Beta7 was giving very similar behavior)

neuron2
12th September 2009, 05:56
:By the way, I think the same bug exists in the DGMPGIndexNV tool ... I haven't tried the latest Beta9, but Beta7 was giving very similar behavior) Yes, I've already fixed it locally and the fix will be in the next beta. Fortunately, it's a very rare case.

SomeJoe
14th September 2009, 02:29
Will test and post back ...


Verified - 1.56b3 works for this MPEG stream no problem.