Editing captured video

[jmstacey]

I have a WinTV-PVR USB2 and I am attempting to digitize our old Hi8 home videos. The capture card has a builtin mpeg2 encoder so the files are just dumped to my hard drive, which was great (at first).

But I need to "touch up" the videos as much as possible. Such as cropping to get rid of the distortion on the edges.

I'm looking for any recommendations you might have to try and avoid any further degradation of the video by unnecassry reencodes.
The best way that I can think of is mpeg2 -> avi -> mpeg2

I just want to make sure there is not better way later to find out I could have done something differently.


Thanks!

[setarip_old]

Hi!

You could instead use TMPGEnc for that type of editing - with no need to convert from and then back to MPEG-2 format...

[jmstacey]

Isn't TMPGEnc a tool to convert avi to mpeg1/2? What about the other processes, such as running it through a denoiser or resizer in virtualdub?

[setarip_old]

Isn't TMPGEnc a tool to convert avi to mpeg1/2?That is only ONE of the several capabilities of TMPGEnc. Another is its ability to process already-existing MPEG files, which is why I said,You could instead use TMPGEnc for that type of editing - with no need to convert from and then back to MPEG-2 format...

[communist]

For highest quality I would capture lossless (Huffyuv etc.) -> touch up in Avisynth -> MPEG2 encoder (or whatever your destination format is).

I wouldnt recommend capturing in MPEG2 if you need to filter / enhance the video further, except you're short of hard disk space.

If capturing to MPEG2 is the only option you have then capture in MPEG2 -> frameserve via DGIndex / DGDecode to Avisynth, do the processing there -> encode with your encoder of choice.

[jmstacey]

Ok, I think I have the process I'm going (have to use).
mpeg2 source can't be avoided due to the capture device. So speaking of capture device, are there any programs that can use the wintv's hardware encoder so I don't have to buy a software encoder. Then I can just setup virtualdub as a frameserver and have the hardware decoder do the work. Hopefully speeding things up.

[olyteddy]

I too have the USB2 PVR. You can set up a capture profile that will minimize encoding artifacts. I'd recommend 8 Mb constant bit rate with GOPs set to 6. Unfortunately, you can't add filters to already encoded material without re-encoding. Over on the Hauppauge board IIRC I saw some registry settings that allow you adjust the Conexant encoder's filters.

[jmstacey]

I saw some registry settings that allow you adjust the Conexant encoder's filters.

That sounds interesting. Any idea what kind of tweaks are possible? I haven't found anything on that yet.


What I'm trying now is capturing at 12Mbits/sec (max) and going through avisynth to quenc. But I'm having trouble. I have just a simple script.

DirectShowSource("F:\Jon's Video\Part2.mpg", fps=29.970)

The video plays faster than it should in virtualdub, but the length is the same. (dropped frames?) The original mpeg plays perfectly fine and 29.970 is reported through both virtualdubmod and windvd.

The results in Quenc are the same. The video is fast, sound is normal, and every so often the screen goes grey.

This is with avisynth 2.5. I will try 2 after some sleep and I can find the ConvertToYV12() module.

[communist]

Use DGIndex/DGDecode to frameserve it to Avisynth. Also It would be a good idea to use Avisynth 2.5.6.

[olyteddy]

Google 'Hauppauge Tweak Tool'. It says its for the PCI PVRs, but many of the settings will work on the USB2.

[jmstacey]

Would something like the WinTV usb2 be something worth trying? According to the specs it transfers the raw video to your computer without hardware decoder. Does anybody know if I would be able to capture that directly to a lossless codec through virtualdub?

[setarip_old]

mpeg2 source can't be avoided due to the capture device.Have you tried TMPGEnc, as I suggested earlier in this thread?

[jmstacey]

I can finally move on to a more important issue, dropped frames due to poor tape quality. I'm working on some 20 year old mini casette tapes and there are many areas where the capture device can't digitize the video although audio comes through alright.
So when the dvd is made there are parts of the video that freeze or stutter.

Are there any graceful methods of fixing it in such a way that the dropped frames are not noticeable during playback? Cutting it out wouldn't work very well as that would probably leave 5min of the original 30min of video :scared:

Frame drops always occur when the vcr player adjusts tracking, which takes several seconds. I thought about capturing the video twice (2nd time focusing on the bad areas), are there any programs that can compare the two files, sync them and replace the master with any available frames that might have been captured on the 2nd (or 3rd+) rounds?

setarip_old,
Sure did and it works fine, but I don't feel like forking over additional money just to reencode an already mpeg2 video. I was able to exchange the Hauppauge for the Pinnacle 700 (same price) so now I get the best of both worlds (raw avi output or hardware mpeg2/4 encoding).

[setarip_old]

to reencode an already mpeg2 videoAs far as I know, using TMPGEnc as follows does not involve reencoding:

TMPGEnc>>File>>MPEGTools>>Merge&Cut

Be thata s it may, it's good to hear trhat you've found a hardware solution to your dilemma ;>}