Using VDub Without Quality Loss??

[christopheramos]

Hello,

I want to load a MPEG 2 video files (20 minute TV episodes) into vdub for using a filter. I have two questions:

1. I guess that my first step will be to use Vdub MPEG 2 rather than the regular Vdub program (because my import files are not in .avi format)? Is this correct? and

2. Is there a way to export the file without quality loss? Or without any noticable quality loss? (These files are going to be played on a regular standalone DVD player and TV). I've tried frameserving in the past, but the output file looks worse than the import file. And if I save it as a straight un-compressed .avi file, it's going to be HUGE!!!

Thanks!
Chris

[gadgetguy]

1 - Yes
2 - No. You are recompressing a compressed file. There will always be some loss of quality, but how noticable it will be depends on the quality of the source and the capabilities of the encoder. (Both the software and the person using it).

[christopheramos]

Well, I would say the quality of the source MPEG files is 8 out of 10.

I am looking for the best way, then, to limit loss. Should I frameserve through an encoder (like TMPGEnc Plus or something), or use something else?

Thanks!

[gadgetguy]

Yes, frameserving to an encoder would be the best way. Which encoder is best is not a question I can answer since I don't re-encode mpeg2, but many people swear by TMPGEnc Plus, so I would think that if set correctly, it should produce an acceptable output.

[christopheramos]

gadgetguy,

I was just curious, if you don't re-encode to MPEG2, what do you?

[jagabo]

Instead of VirtualDubMPEG2 or VirtualDubMod you could use AVISynth for filtering and frameserving. That would allow you to leave the video in YV12 format. That would be faster and avoid the small degredation caused by YV12/RGB conversion in VirtualDub. Filter setup in AVISynth is much more of a pain though.

[christopheramos]

Yeah, I've heard great things about AVISynth, but I got to admit, I tried it and could not figure it out at all. So I gave up, looking for something simpler.

[gadgetguy]

Most of the source material I work with is in DV-AVI which I then encode to mpeg2 for DVD authoring. I don't think of mpeg2 as a suitable source format, so the only thing I do with mpeg2 as the source is simple cuts without re-encoding using Cuttermaran.

[christopheramos]

Yeah, I plan to use Cuttermaran for editing out commercials, as it won't reauthor, but the problem with wanting to use a vdub filter means that I am going to have to re-encode somehow.

I guess I'm just looking for the best way to do that and retain as much quality as possible.

[gadgetguy]

... but the problem with wanting to use a vdub filter means that I am going to have to re-encode somehow...

That's true, and as I stated the best bet for using Vdub filters will be to frameserve to an encoder, but it will be up to the encoder to minimize the loss.

Depending on what filters you want to use, AviSynth would probably be better and faster, but as you pointed out, it is much more difficult to learn to use than Vdub, (but well worth the effort IMO).

Edit: I think that if I were to going to attempt this, I would use HCenc as the encoder and experiment with different matrices on small samples to see what would give me the best results with the filtered source. HCenc allows you to specify the number of frames (and which frames) to encode so you wouldn't need to cut the video up before frameserving. And you could target the frames that would seem to be most troublesome.

[redwudz]

What I have done with MPEGs is to do the filtering With VirtualDub Mod and save out the video as DV, then edit the DV to remove commercials. DV is one of the easiest formats to edit as every frame is a key frame so frame accurate editing is easy. Then I encode the result to MPEG-2. DV is fairly low loss and the convenience of being able to do frame accurate edits is worth it for me. For editing, I put the DV back into VDM and use that, then frameserve that to TMPGEnc encoder.

To convert to DV with VirtualDub, or my choice, VD Mod, you need a DV codec. I use the Panasonic DV Codec.

For lower losses, directly frameserving to your encoder, or best, using a program like AVISynth for the filtering and frameserving would probably have the lowest losses. But I still don't know AVISynth very well.

Most of the time my video starts as DV, so I can do it all in VDM and just frameserve it to the encoder. I convert the DV audio to AC3 with ffmpeggui before authoring.

[christopheramos]

Okay, thanks! I am getting a better picture of this now.

So, after I import the MPEG 2 files and use Cuttermaran to edit out the commercials, my next step will be to load it into Vdub, Vdub Mod, or Vdub MPEG.

When I run the file through a filter in Vdub, what is the best output format? In terms of wanting to play these files on a standalone DVD player?

I plan to frameserve using TMPGEnc XP. But for what I want to do, should I my export video (from TMPGEnc XP) remain in MPEG 2 format? Or such I export it in a different format, for best results?

Thanks!
Chris

[jagabo]

The regular version of VirtualDub does not read MPEG 2 so you have to use VirtualDubMPEG2 or VirtualDubMod.

When frameserving you are passing video directly from VirtualDub to TMPGEnc. TMPGEnc will save the video as MPEG 2.

If you are using a regular set-top DVD player you have to save as MPEG. That's the only thing they play (MPEG video in a VOB container). There are many restrictions on the frame size, frame rate, bitrates, etc. So you must use DVD compatible settings. Then you must use DVD mastering software to create all the other information needed for DVD.

If you have a Divx/DVD player you can skip TMPGEnc and save directly from VirtualDub as Divx or Xvid AVI.

[christopheramos]

Okay, but what you mean by this quote:

"Then you must use DVD mastering software to create all the other information needed for DVD."

Are you talking about the settings in my DVD authoring program (DVD Lab Pro 2)?


Thanks!

[jagabo]

Okay, but what you mean by this quote:

"Then you must use DVD mastering software to create all the other information needed for DVD."

Are you talking about the settings in my DVD authoring program (DVD Lab Pro 2)?

Yes.

[christopheramos]

Great!!! Thanks. Just one last thing. Jagabo said:

"There are many restrictions on the frame size, frame rate, bitrates, etc. So you must use DVD compatible settings."

How/where can I learn more about the proper settings for these things?

Thanks!
Chris

[jagabo]

What is DVD: https://www.videohelp.com/dvd

You can use the presets in TMPGEnc to get DVD compatability.