FFDShow don't load correct codec, Mpeg2

[marcorocchini]

Hi @ all

here attach my reference file: output.avi

it's a mpeg2 avi file

I can import it on my nle (blade 2.2) if I install on the system (windows xp) ffdshow and able it to read "mpegInAvi"

I also have to do this association: vidc.mpg2=ff_vfw.dll in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32

Now I can open it in my nle, but strangely ffdshow open it with libavcodec/mpeg1 or libmpeg2/mpeg1 ... not with the mpeg2 codec and playback is wrong, 1°frame is black and image is pixelated.

The same thing happens when I try to open it in virtualdub: no mpeg2 codec loaded in the ffdshow = wrong playback

Can I force ffdshow to open it with the mpeg2 codec?

[El Heggunte]

My copy of VirtualDub opens MPG-in-AVI fine, and I don't need to set

"vidc.mpg2=ff_vfw.dll" @ HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32 ,

so my guess is, it's that new entry in the Registry which doesn't let ffdshow work correctly on your machine

If I were you, I would start looking for a less-outdated and less problematic NLE

[marcorocchini]

no simply you have installed ffdshow with the "virtualdub plugin" (=ffvdub.vdf in the plugin directory of virtualdub)

if you uninstall ffdshow and reinstall it without the virtualdub plugin option, you can not open output.avi with ffdshow.

But if you add vidc.mpg2=ff_vfw.dll in the registry .. magically virtualdub open it with ffshow

[jagabo]

The ffmpeg source plugin for VirtualDub works fine with your video here. It shows it's using the mpeg 2 decoder.


Using the AVI source reader/splitter in VirtualDub with ffmpeg's VFW decoder works but shows blocky artifact problems with random seeks.

[marcorocchini]

however in my pc the .avi file saved by virtualdub have initial frames (the firts 3-4 frames) broken, do you any solution to avoid this? thanks

[marcorocchini]

ps I have do use the directshow channel in my nle, that do the same problem: initial frames wrong.

The same defect happens to virutaldub when import from ffdshow VFW decoder.

Otherwise can I adapt ffmpeg-decoder for my nle so I put a dedicated driver (e.g. driver.dll) in a directory and I set the registry vidc.mg2=c:\driver.dll

but I now this driver have to be a VFW driver, so my answer is: only exist ffdshow to the world or any other vfw-ffmpeg based decoders?

[poisondeathray]

As mentioned in the other thread , directshow is not necessarily frame accurate, and should NEVER be used for editing (or non linear seeks, or any scrubbing)

[jagabo]

Your source was cut from a video with open GOPs. The first few frames can't be reconstructed because they need information from the prior GOP. Just use Trim() to remove them.