VCD encoding with ffmpeg

[arijitm]

Hi

I'm a newbie in video editing - just started to create DVD and VCDs of my travel shots from my miniDV cam (NTSC). I'm on a Mac PowerBook G4, 1G RAM, and I'm using iMovie 5.0.2 (I guess the latest one) to do the editing. I exported the edited movie to a full quality DV stream, and now trying to use that (a DV file of about 10G size) to create a DVD and a VCD - the movie length is about 46 minutes. My DVD player and TV are all PAL. So there's an issue of quality loss there - although I'm not sure how much it would affect.

I have been able to create a DVD using iDVD (from Apple) by just dragging the DV stream onto iDVD and letting iDVD do the rest - although I had to use the "best quality encoding" to remove the jerky playback on TV which happened when I did a normal encoding. The "best quality encoding" takes quite a while.

The problem is with the VCD - I'm using "ffmpeg" for encoding - encoding the DV stream to MPEG-1, using the standard VCD settings of ffmpeg - only changing the size to 352x288 (that's what I thought the size for PAL is). However, when the final video is produced, the playback (with QT or VLC) at "actual size" is fine, but "full screen" is pixelated - with less clarity. I created the VCD with Toast Titanium 7, and the playback on the TV was same - with less clarity.

I know I won't get the same quality as a DVD, but I thought I would get atleast the same quality as some standard VCD movies (brought from India - commercial movies) I have - but the quality I get is no where near that...Those commercial VCDs when played on the computer using QT or VLC and blown to full-screen has the same clarity as the tv playback.

Questions -

(1) There's a resolution setting in the video option of ffmpeg - which I set to 352x288. What about the size? Does it affect the playback quality?
(2) Does a conversion of NTSC to PAL cause any kind of kery playback (which I'm getting)?

Hoping for some guidance - thanx in advance,

Regards
Arijit

[PiggyWiggy]

For one, you should use SVCD!! Why use VCD? SVCD is MPEG-2 so better quality... VCD does look a little bit bland and pixelated on TV, but SVCD is of better quality and the difference with DVD isn't that noticeable on a normal TV when using SVCD... If for some reason you can't use SVCD, then I think there isn't a real solution to yuor problem, VCD just that aint great of quality.

By the way, I don't believe the conversion from NTSC to PAL should cause any noticeable quality loss... I've been doing it for a couple years and no real reason to complain yet.

[guns1inger]

Why use either, and yes, pooor format conversion will lead to jerkiness due to poor framerate conversion. It can also cause colour issues due to the different IRE levels used.

[arijitm]

For one, you should use SVCD!! Why use VCD? SVCD is MPEG-2 so better quality... VCD does look a little bit bland and pixelated on TV, but SVCD is of better quality and the difference with DVD isn't that noticeable on a normal TV when using SVCD... If for some reason you can't use SVCD, then I think there isn't a real solution to yuor problem, VCD just that aint great of quality.

Thank you! I'll try an SVCD and see how it goes - my DVD player will probably play that, but I'm not sure whether it will play at its actual destination - I'm creating this for my family back home, and don't know whether the VCD player there supports SVCD or not(

[arijitm]

Another stupid question - what's the difference between the "resolution" and "size" settings in the video tab? I mean, the VCD (for example) resolution is 352x240/352x288 - should the size be the same? Or can I choose other sizes? Would ffmpeg allow that?

[PiggyWiggy]

Useally the 'newer' DVD players should play SVCD.. If its older then, well, let's say 2 years it may not work though, but it doesn't hurt to try. But. what the other poster said... Why not just burn it on DVD? Easier to do and the quality is better...

As for the res. and the size.. I think you mean with the size, the drop-down menu? That's just for autosizing, so you can pick a width and then pick a resolution from the drop-down menu which will calculate the height automatically.

[Case]

The VCD (for example) resolution is 352x240/352x288 - should the size be the same? Or can I choose other sizes? Would ffmpeg allow that?

ffmpegX will allow that, but the result wouldn't be a VCD, as the specs define only those resolutions. If (big if) your player supports it, you could create an out-of-spec VCD, or XVCD. Not really recommended, but FYI.

[arijitm]

Just bumped into http://www.pcphotovideo.com/interest.htm - this page contains some samples of VCDs - and rather good quality. How can I get this type of stuff? I mean the quality, size/aspect ratio - the normal 352x240 resolution with 4:3 aspect ratio doesn't give this type of appearence or quality???

[gadgetguy]

How can I get this type of stuff? I mean the quality, size/aspect ratio - the normal 352x240 resolution with 4:3 aspect ratio doesn't give this type of appearence or quality???

They are VCD so they are 352x240, etc. But I have to wonder what the signal source is. My cable service has never been that clean...ever.

[Case]

Don't think your "travel shots" will ever be movie quality. A light crew and digital grading make such a huge difference. There is this article on digital photography (close enough?) that explains how contrast fools the eye into perceiving better qulity.

[arijitm]

Thanx everyone. I am now getting into the groove - slowly. One more question - possibly I'll be able to get a firm grasp.

The link that I posted earlier had MPEG-1 samples, with details such as 352x240, 1150kbps, and 29.97fps - NTSC - shows up when this is dropped onto ffmpeg. But, using QT movie info, this is 320x146, 1395.68kbps and 29.97 fps.

Why would this information be different? And 320x146 is not a standard VCD, right? Or, is it possible to create this sort of effect with 352x240 resolution?

Sorry if I'm being stupid

[PiggyWiggy]

The resolution difference is weird, the bitrate is variable though, so that it's higher is normal.