Can't create graph that grabs HDV samples

[Mike]

I am unable to create a graph that grabs samples from an HDV source (like a Canon HV30 connected via firewire in HD mode). In GEP I can get preview working using the M$ DTV-DVD Video Decoder but I cannot insert samplegrabber into this graph as it won't connect to this decoder (I've read it only outputs VIH2). If I replace this decoder with the GPL MPEG-1/2 Decoder I can connect samplegrabber, but this decoder does not want to work in GEP (output SD black frames). I know this decoder works fine using another app btw. Any suggestions?

[Dee Mon]

Is it possible to save a stream from camera to a file and reproduce the situation without the camera?

[Mike]

I grabbed to original stream and saved 10 seconds to disk. Plays fine in WMP but if I try to render it in GEP (or GE) it can't. If you want to have a look you can find it here.

[Dee Mon]

Thanks for the file!
I've just tried to play it in GEP and had no problems. I used GPL MPEG-1/2 Decoder 0.1.2 and Haali Media Splitter 1.8 from the K-Lite Codec pack.







Do you use the same version of the decoder?

[Mike]

Impressive! I do not have Haali installed as it caused lots of problems with earlier projects (also I do not know if I could even add it to my commercial products). What surprises me is that you can get SG to connect to the MPEG decoder, while I could not. When I'm back in the office I'll have to compare version numbers.. I assume you too are unable to get it working using M$ demux?

[Dee Mon]

I don't have MS DTV-DVD Video Decoder but instead I've got MS MPEG-2 Video Decoder which works fine.

[Dee Mon]

I've just tried it on a Windows 7 now, there MS DTV-DVD Video Decoder is present.
It does output only VideoInfo2, and sample grabber indeed cannot accept this data. This is a limitation of the sample grabber filter. In one of our products (Video Enhancer) we had to make a filter which converted VideoInfo2 stream to VideoInfo and inserted it before the sample grabber.

GPL MPEG decoder works fine in Win7 too.

[Mike]

Thanks, but getting back to my question: you cannot make it work with the M$ demux right? Only with Haali? I can't use that I'm afraid..

[Dee Mon]

Mike, this is a limitation of the sample grabber filter which is a part of DirectShow itself. It has nothing to do with application it's used in - GraphEdit, GEP or anything else. If MS DTV-DVD outputs only VideoInfo2 the issue doesn't depend on the source filter, so Haali or File Source - doesn't matter.

In other words: MS DTV-DVD and sample grabber cannot be connected directly. You need to either change one of them to an alternative (other decoder or your substitute for sample grabber), or insert a converter between them.

If you can't change the decoder, just take an example of TransInPlace filter from DirectShow samples and make a substitute for sample grabber which can accept VideoInfo2 streams.

[Mike]

Afraid you do not understand my question. I cannot make it work with GPL MPEG-1/2 and the M$ demux, as the grabber won't connect to the decoder (see my first post). You have proven that it can, so the problem must be in the demux, hence my question.
If you still do not understand my question, I could also ask: can you make it work without haali?

[Dee Mon]

Yes, I can make a graph with GPL MPEG decoder and sample grabber without Haali:



In this case the file is read by File Source Async (standard DirectShow reader) and splitted by Gabest Mpeg Splitter from the K-Lite codec pack.

GPL decoder receives Mpeg2Video, so someone must parse the stream and make Mpeg2Video out of raw file data. Haali reader did this, and when it's not used another splitter must be used, in this case the Gabest's splitter. I don't see Microsoft demux in the list of filters, a decoder is not a splitter.

[Mike]

Again you use a component not generally available (or for sale) although I specifically mentioned this limitation

Maybe the file is not exact the same as the hdv stream from the camera, in that case I need a demux, not a splitter. At least intelligent connect always adds a demux.

So it seems that

1. hooking up the camera is not the same as playing the file (which really makes point 2 mute), and

2. although the file plays fine in WMP you cannot play it in DirectShow using standard Windows filters.

It is interesting how easy it is to setup a graph for DV (sample)capture, while it (apparently) is extremley difficult to do this for HDV. I was hoping you could do this but I guess you at least need an HDV camera for that. Thanks anyway.