Transport stream support in DVD2AVIdg/MPEG2DEC3dg

[neuron2]

I've just added ATSC transport stream support to my DVD2AVIdg/MPEG2DEC3dg package. The latter does correct decoding and random access without losing frames. I'd be interested in feedback from members of this forum. My intent is to add support for other transport formats, but I will need pointers to specs and test streams.

Please go to the DVD2AVI forum to get the 1.3.0 version of my package.

Thank you.

[Doom9]

when it comes to DVB you should find the necessary specs at www.dvb.org, more specifically: http://www.dvb.org/index.php?id=57

I'm not sure about ISDB, but we used to have a rather vocal Japanese HDTV supporter around.. maybe he can enlighten us as I've been unsuccessful in finding too much info about the Japanese broadcast standard.

[kikounet]

Thank you very much!

And where is the last version of MPEG2DEC3dg (the one that should match with DVD2AVIdg)?

I do my satellite captures with ProgDVB (save in *.MPG mode) then try to convert them with Gordian Knot.

[neuron2]

Originally posted by kikounet
And where is the last version of MPEG2DEC3dg (the one that should match with DVD2AVIdg)? It's packaged with DVD2AVIdg.

I don't know if it will play your streams. Please tell me. If not, I will make it do so. Thank you.

[SeeMoreDigital]

Originally posted by neuron2
Please go to the DVD2AVI forum to get the 1.3.0 version of my package. Are you able to provide a direct link please?


Cheers

[neuron2]

Sure.

http://neuron2.net/fixd2v/decodefix130beta6.zip

Be sure to use DVD2AVIdg and MPEG2DEC3dg as a pair.

[SeeMoreDigital]

Originally posted by neuron2
Sure.

http://neuron2.net/fixd2v/decodefix130beta6.zip

Be sure to use DVD2AVIdg and MPEG2DEC3dg as a pair. Hey, I've done a quick test and it appears to work great!


Cheers

[neuron2]

Thanks. Lots of cool things are coming:

PAT/PMT and PSIP parsing (PID detection)
PVA format
stream cutting (delete commercials)
etc.

[trbarry]

stream cutting (delete commercials)

YES! :)

- Tom

[Doom9]

@neuron2: one thing about the commercials: Do you plan to do actual cutting (thus restricted to b-frames for an "out" cut and i-frames for an "in" cut) or just limit the d2v output (so that it's frame accurate) (or both)? While the former is most useful for people that do no further processing of the output (well.. assuming it's DVB or D1 res ATSC.. I doubt most people will keep the full HDTV TS), the latter would be most useful for people that'll re-encode their captured streams.

[neuron2]

Before DVD2AVIdg has frame accuracy, I can only do GOP level granularity. The idea is that the parser can be told to stop delivering audio and video for given LBA ranges that correspond to GOPs. This should be good enough for people that don't post-process. You can always get frame accurate in post, but then you have to handle audio separately. What do you think of that?

BTW, get 1.3.0 RC2. RC1 was brain-dead.

[Doom9]

I see you reformulated your question. Basically I see two ways to cut a TS / PVA / mpg from a digital TV source:

1) cut the actual file. Assume you have your capture ts/pva/mpg source, and you cut away commercials, resulting in a smaller ts/pva/mpg that contains just the video and audio you're intersted in.

2) you create your d2v file that contains only parts of the source you're intersted in. So, instead of physically cutting ads away and create a new file that contains the movie without ads, you create a d2v that just contains what you're interested in. Many programs these days take d2v files as input, so if you could mark ranges in dvd2avi, and then create a dvd2avi project file, the d2v would be used to frameserver only the range from the recorded content that you're really interested in.

the best way to be frame accurate so far is either to use avisynth (if you're going to re-encode) or use a program like cuttermaran that can re-encode up to one gop (in case you want cutting down to a frame-accurate level rather than just an i-frame level).

[neuron2]

Well, obviously I am thinking of 2) until DVD2AVIdg gets frame accurate.

I too have been contemplating frame accuracy and reencoding.

BTW, it is a misconception that you can always cut safely at an I frame. Ergo: IBBPBBPIBBPBBP. You can't cut safely at the second I frame without reencoding.

Is the source for cuttermaran available?

[Doom9]

Is the source for cuttermaran available?Yes, you can download it here: http://people.freenet.de/toarnold/cuttermaran/cuttermaran_e/download.htm

IBBPBBPIBBPBBP. You can't cut safely at the second I frame without reencoding.Hmm.. now I need a lesson as I don't see what would prevent cutting at the 2nd i-frame.

[neuron2]

Originally posted by Doom9
Yes, you can download it here: http://people.freenet.de/toarnold/cuttermaran/cuttermaran_e/download.htm Excellent! Thank you very much.

Hmm.. now I need a lesson as I don't see what would prevent cutting at the 2nd i-frame. If you make the cut you are left with this: IBBPBBP. The first frame in display order is the first B frame (it's before the I frame in display order!), so the forward reference frame for that B frame is in the GOP that you cut away, unless the GOP is closed. This is one of the root causes of the frame losses of the non-DG versions of DVD2AVI/MPEG2DEC3. Ever heard of Xvid's 'B frame lag'?

Remember that in MPEG the encoded order of the frames is different from the display order. A re-ordering is performed by the decoder. The closed GOP flag is there to tell the decoder if it is safe to cut at that GOP. Most of the time it isn't for IBBP... patterns. For IPBB... patterns it is always safe because the two reference frames for the first B frame are within the GOP.