Doom9's Forum - View Single Post - MJPEG to DVD with cropping, filters and CCE/HC/QuEnc MPEG2 encoder

manolito · 28th March 2009, 16:27

Hi uciekamy,

converting analog captured video to DVD....
This is a vast area to cover, simply because there are hundreds of ways to do this. It all depends on the quality you want to achieve and on how much time and effort you intend to invest.

I will try to cover the basics, but be prepared for some obstacles along the way.

Frameserving from VirtualDub is certainly an option, but as you already noticed, some encoders will accept this input, others will not. I would recommend to learn AviSynth scripting, because it is much more powerful and it will work with every encoder.

First thing you have to do is to check if you have to do something to get the correct aspect ratio. I assume you are doing PAL conversions (720 x 576). If you captured analog video at 720 x 576 and convert it to DVD without resizing, chances are that your aspect ratio is slightly off. This has something to do with the "active capture window" of your capture card. For a given card and driver combination this AR error will be constant.

Forum member Arachnotron is THE expert on this. He has a website where you can download test images to determine your AR error. My own situation is like this: I have a BT878 based capture card which I use with Ivan Uskov's tweaked BT8x8 drivers. If I capture in 720 x 576 then the resulting DVD will look slightly stretched horizontally. Resizing by small ratios is never a good idea (Nyquist effect), so my solution is to capture at 696 x 576 and then adding 12 pixel borders to the left and the right side which brings the frame size back to 720 x 576. This gives me the correct AR, and luckily the 12 pixel borders are well within the overscan area of my CRT TV set.

But maybe in your case aspect ratio error is small enough to ignore it. But before you do batch conversions of your many VHS tapes I would certainly recommend to check this.

Next step is to edit the capured video file. Since all I want to do is editing out commercials, I do all my editing in VirtualDub. When I am done I simply save the edited file in Direct Stream Copy mode for video and audio. (Actually I do it using VCF2AVS to translate the editing points into AVS commands, but this is too complicated for now)

Now you have the edited AVI file, and you want to improve quality by applying filters. A word of caution: A VHS capture will never look even remotely like a DVD source. Many beginners tend to use excessive filtering, but the result will look artefial. Human faces can look like taken from a wax cabinet if too much denoising has been applied. So do not overdo filtering.

To see the effects of AviSynth filters I like to use AvsP. For VHS captures the most common filters are denoising and sharpening. You might have to adjust brightness, contrast and gamma. For chroma noise CNR2 is very nice. Much depends on your specific VCR. My VCR tends to oversharp edges which I try to fix using the "FixVHSOversharp" filter. In any case you will have to do a lot of experimentation. Better filters are mostly slower than simpler ones, so you have to find the right balance for your needs.

A sample AVS script would look like this:

Code:

AviSource("My_CapturedAVI.avi")

# Optional Deinterlace
AssumeTFF()
LoadCPlugin(yadif.dll)
Yadif()

FixVHSOversharpL(30,12,8)
FixVHSOversharp(30,14,10)
ConvertToYV12(interlaced=true)  # or false
AddBorders(12,0,12,0)
cnr2()
degrainmedian()
undot()
asharp(1,4)

Please note that I only use very fast filters because my computer is so slow. You can get much better results using other filters like fft3d, LimitedSharpen and so on...

Now the actual encoding: I still use the good old DVD2SVCD software simply because I am very familiar with it and it gives me a lot of control over all the parameters. But there is a learning curve. It supports CCE, Quenc, HC, TMPGEnc and Procoder.

Another excellent AVI to DVD software is AVStoDVD. It supports HC and Quenc (not CCE), it is very easy to use, and it lets you use custom AVS scripts.

Well, there is a lot more to consider (deinterlace or not, matrix selection for the encoder, convert audio to MPA or AC3), but this post is too long already...

Let me know about your progress

Cheers
manolito

28th March 2009, 16:27	#4 \| Link
manolito Registered User Join Date: Sep 2003 Location: Berlin, Germany Posts: 3,079	Hi uciekamy, converting analog captured video to DVD.... This is a vast area to cover, simply because there are hundreds of ways to do this. It all depends on the quality you want to achieve and on how much time and effort you intend to invest. I will try to cover the basics, but be prepared for some obstacles along the way. Frameserving from VirtualDub is certainly an option, but as you already noticed, some encoders will accept this input, others will not. I would recommend to learn AviSynth scripting, because it is much more powerful and it will work with every encoder. First thing you have to do is to check if you have to do something to get the correct aspect ratio. I assume you are doing PAL conversions (720 x 576). If you captured analog video at 720 x 576 and convert it to DVD without resizing, chances are that your aspect ratio is slightly off. This has something to do with the "active capture window" of your capture card. For a given card and driver combination this AR error will be constant. Forum member Arachnotron is THE expert on this. He has a website where you can download test images to determine your AR error. My own situation is like this: I have a BT878 based capture card which I use with Ivan Uskov's tweaked BT8x8 drivers. If I capture in 720 x 576 then the resulting DVD will look slightly stretched horizontally. Resizing by small ratios is never a good idea (Nyquist effect), so my solution is to capture at 696 x 576 and then adding 12 pixel borders to the left and the right side which brings the frame size back to 720 x 576. This gives me the correct AR, and luckily the 12 pixel borders are well within the overscan area of my CRT TV set. But maybe in your case aspect ratio error is small enough to ignore it. But before you do batch conversions of your many VHS tapes I would certainly recommend to check this. Next step is to edit the capured video file. Since all I want to do is editing out commercials, I do all my editing in VirtualDub. When I am done I simply save the edited file in Direct Stream Copy mode for video and audio. (Actually I do it using VCF2AVS to translate the editing points into AVS commands, but this is too complicated for now) Now you have the edited AVI file, and you want to improve quality by applying filters. A word of caution: A VHS capture will never look even remotely like a DVD source. Many beginners tend to use excessive filtering, but the result will look artefial. Human faces can look like taken from a wax cabinet if too much denoising has been applied. So do not overdo filtering. To see the effects of AviSynth filters I like to use AvsP. For VHS captures the most common filters are denoising and sharpening. You might have to adjust brightness, contrast and gamma. For chroma noise CNR2 is very nice. Much depends on your specific VCR. My VCR tends to oversharp edges which I try to fix using the "FixVHSOversharp" filter. In any case you will have to do a lot of experimentation. Better filters are mostly slower than simpler ones, so you have to find the right balance for your needs. A sample AVS script would look like this: Code: AviSource("My_CapturedAVI.avi") # Optional Deinterlace AssumeTFF() LoadCPlugin(yadif.dll) Yadif() FixVHSOversharpL(30,12,8) FixVHSOversharp(30,14,10) ConvertToYV12(interlaced=true) # or false AddBorders(12,0,12,0) cnr2() degrainmedian() undot() asharp(1,4) Please note that I only use very fast filters because my computer is so slow. You can get much better results using other filters like fft3d, LimitedSharpen and so on... Now the actual encoding: I still use the good old DVD2SVCD software simply because I am very familiar with it and it gives me a lot of control over all the parameters. But there is a learning curve. It supports CCE, Quenc, HC, TMPGEnc and Procoder. Another excellent AVI to DVD software is AVStoDVD. It supports HC and Quenc (not CCE), it is very easy to use, and it lets you use custom AVS scripts. Well, there is a lot more to consider (deinterlace or not, matrix selection for the encoder, convert audio to MPA or AC3), but this post is too long already... Let me know about your progress Cheers manolito