need help with screenshots for codec comparison

[Doom9]

I'm telling you, those screenshots will be the end of me. Here's how it usually works: since all codecs use overlay, I'm having two copies of MPC open.. the movie in the first one grabs the overlay so I can snap the movie in the 2nd window. So far so good and it worked flawlessly before. Now apparently all codecs seem to use different overlay mechanisms that create some problems.

Using a divx5 clip as primary source I can snap ffvfw, xvid, vp6, divx3 and the original avisynth script in the secondary mpc copy (the one without overlay).

But opening 3ivx, nerodigital and rv9 in the secondary mpc leads to discoloration (I can snap it though). In order not to get discoloration I can use another primary video clip like XviD in YV12 output mode. Then I don't have any discoloration problems in the secondary player, but the secondary clip uses overlay so I cannot make screenshots. Now for 3ivx and NeroDigital I have found a solution: Render the AVI in Graphedit and add the Color Space converter before the output which forces YUV2 output that I can apparently capture just fine. The only problem.. I cannot play the graph in MPC and without MPC taking screenshots is a major problem because you cannot tell the player to go to frame X. So is there any way to get a graph to play in MPC?

For RV9 it's even worse because I cannot even render that in Graphedit.

So, I'm looking for a way to make screenshots from within MPC from 3ivX (v4.5), NeroDigital and RV9 content without discoloration. Any ideas? I've tried pretty much every combination of primary and secondary source and every possible primary source color space output (the xvid and ffdshow filter allow to specify the output colorspace), but without any success.

Now please, I wouldn't post if it were obvious so please only post if you have a working solution that you have tested.

Also, I have already tried AviSynth scripts (DirectShowSource) using the Convert commands AviSynth offers... ConverToRGB24, CovertToYUY2 and CovertToYV12 are a nogo.

And I really do need the stuff filtered so opening a file in VDub isn't a solution (plus it wouldn't work for RV9 anyway).

[Manao]

Why not using a basic avisynth script with only DirectShowSource, and make the screenshots from VDubMod ?

[Doom9]

manao: last time I tried that I couldn't use VDub(Mod)s Go to function.. it would leed to freezeing. Now it seems AviSynth's directshowsource is finally usable wrt to go to which solved 3ivx and NeroDigital (thanks!), but RV9 remains a problem because that's not DirectShow.

[scharfis_brain]

@doom9: why don't you just disable all HW-acceleration of your Video-Card?

Just set this slider to to LEFT:
http://home.arcor.de/scharfis_brain/samples/HW.png

Then every Overlaying mechanism is disabled and Screenshots can be done easily.

[celtic_druid]

RV9 should work fine using directshow, that is if you have Gabest's dshow real splitter installed.

[DAvenger]

Just use VMR7 or 9 in mixing mode and you can take as many screenshots as you want ;)

[Atamido]

As a small test, you might try putting all of the videos into a single MKV. If the codecs and Directshow all want to play friendly you should be able to take a screenshot of several at the same time. Of course, DirectShows combination of threading and buffering might put all of the videos at different spots, but if it worked it would save a load of time.

Something like this. (http://www.jkfanclub.com:81/Multiple_video_streams.png)

[Doom9]

@davenger: this does indeed work but the color tones are different than in standard mode.

@celtic_druid: indeed it works but it seems the colors are off a bit, too.

But, then I figured out that the "normal" MPC mode actually makes rmvb clips appear darker.. I compared against other codecs and the original and the color tones seem to be fine. So thanks to all of you.

@Pamel: that sounds like an interesting option but as you I have my doubts. Already now, I have to deal figure out delays in number of frames for different codecs to get the same frame. I have offsets for ffvfw (3 frames), divx3 (-1 frame), divx5 (+1 frame) and the avisynth script (+1 frame).. and that's only for Matrix.. who knows what lurks ahead for the other two sources and RV9.