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logicTrAp
01-06-2002, 06:37 PM
I've recently gotten a Tivonet and am trying to extract some video to make VCDs or SVCDs from my HDR212, upgraded with an extra 100GB disk. However, I'm having difficulty...
Trying to use ExtractStream to extract split audio and video streams causes it to hang after extracting a couple of hundred megs (of a1.4GB show, 1 hour long, recorded at best quality). Extracting raw tystreams with both sendstream and ExtractStream produces tystreams which look to be about the right size (Although somewhat different between the two, which isn't so surprising given the sendstream comments about length calculation). Once I have the tystream however, I'm having some problems getting it into a useful form. splitstream produces, for both sendstream and extractstream-extracted streams, roughly the following (from the 1.4GB input tystream):
31 megabyte audio file
499 megabyte video file
939 megabyte "badchunk" file
In both cases it spits a lot of errors out, like
Warning: large sequence mismatch. Expecting 0:0, got 15f:9ef98d24 in chunk 0 rec
ord 0 last audio time 00:00:00.0 last video time 00:00:00.0
No first frame, skipping chunk 0
...
audio failure 0:0x1f0 0x73:0x5e:0xe7 chunk 2 last audio time 00:00:00.0 last vid
eo time 00:00:00.0
Warning: found even earlier Audio frame, add -0.000000 to min audio delay chunk
2
Warning: found even earlier Video frame, add 266.944444 to min audio delay chunk
2
...
etc.
Listening to the audio, it does start at the correct place, but is only a bit over 20 minutes long. I can't find anything on Linux that will play the video (vlc, ogle and xine all seem unhappy with it). Taking another track, I tried used tyc to convert the tystream directly to an mpeg file. This produces:
453MB mpeg file from sendstream
842MB mpeg file from extractstream
Both files seem to start at the same place (they play fine with vlc) but the sendstream file is only about 34 minutes long while the extractstream file shows up as being about 1 hour, 4 minutes long. However, they both seem to start about 10 or 15 minutes into the program. While converting, tyc spits out lots of error messages like:
Skipping chunk bad timebase
Timecode jumps!
Skipping bad time check.
Skipping chunk bad timebase
Skipping chunk bad timebase

Anyone have any hints? I greatly appreciate any help. I've put up the relevant log files at
http://www.chiappa.net/~chris/tivostream
I'm fairly handy with C and Linux and have the Tivo cross compiler working, so I can try any hints offered.

logicTrAp
01-06-2002, 06:42 PM
I should also note that I'm using 2.5.1 and VBR. Is this likely to cause problems?

Attack
01-06-2002, 11:45 PM
Extracting VBR streams don't work from everything I have read.

You should use TivoApp (http://home.earthlink.net/~garyw90/TivoApp.html) with Tivoweb. The main thing you need to do is edit your hosts file and make tivo point to the ip of your tivo.


Also if you could give me any help at getting the cross compiler working with RH7.

logicTrAp
01-07-2002, 12:08 AM
That sucks, I guess the American Gothic marathon I recorded is toast then. Damn shame given that SciFi doesn't even show it regularly any more. At least I know for the future now tho...

TivoApp's not an option since I don't use Windows. At least for the Cross Compiler, I just downloaded the binaries I found somewhere (don't have the link offhand) and have been using that...

Thanks for the hint

Attack
01-07-2002, 12:41 AM
You should still download TiVoApp as he has some bug fixes added to extractstream. It was able to extract a show that I could not get with any other extraction software.

logicTrAp
01-07-2002, 01:18 AM
Unfortunately, even with a non-VBR recording, neither sendstream nor the tivoapp ExtractStream are having any more luck...they extract fine but both tyc and splitstream produce similar errors and tyc produces very little actual video (~200KB from a 630MB tystream). Anyone else have any hints?

Attack
01-07-2002, 12:40 PM
Sorry, I don't know what the problem could be :( , as I just extracted last nights :) Futurama :) about 20 minutes after it aired. I used the TiVoApp and had it do a split a/v file. I played the mv2 file in Power DVD and it played all the way thru with out any errors.

logicTrAp
01-07-2002, 11:09 PM
I've made some progress - it seems that while the various tystream conversion programs don't work very well, the ExtractStream that comes with TivoApp is somewhat happier when extracting and doing the audio/video splitting itself. With it, I was able to extract a half hour non-VBR simpsons episode and then remux it with mplex on the Linux box and it seems to have done fine. However, trying the 1 hour VBR American Gothic episode I'm really trying to extract it gets most of it, but gets some errors about sector mismatches and in the end the extracted video is missing a couple of minutes chunk in the middle, after which the audio quits. However it looks like Jeremy Gordon over at the Yahoo ExtractStream group has been making some progress with more robust extraction - http://groups.yahoo.com/group/ExtractStream/message/788 as has Ray Waldin in the DirecTivo hacking forum, so I'm somewhat hopeful that things may be working better in the future :)

logicTrAp
01-11-2002, 12:50 AM
attack - think you mentioned you were looking for the cross compiler. It's here - http://www.mib.org/~agt/TiVo/