Trying to understand Frameserving...

[brentd49]

Introduction
I'm frameserving an AVI to MPEG2 (DVD). My AVI is a 640x272 Laser Disc sorce 702MB file encoded in 25fps. I want my final version as a 720x480 29.97fps. I tried both AVISynth2 and VirtualDub for frameserving.

My CCE Settings were:

Main:
Video ES
No Audio
Multipass VBR 3
Avg 6,000 Min 0 Max 9,000

Video:
Add sequence end code
Progressive frames
Linear quantizer
Zigzag scanning order
DVD compliant
Luminance 16 to 235
Auto DC precision
Aspect ratio 4:3
Timecode: 00:00:00:00

GOP:
M=3 N/M=4
SEQ header ever 1 GOP(s)



AVISynth

my script (without dotted line):
................................................
avisource("actualnameofthemovie.avi")
BicubicResize(720,272)
AddBorders(0,104,0,104)
ResampleAudio(44100)
.................................................
script saved as actualnameofthemovie.avi.avs and loaded into CCE

VirtualDub

(Didn't change VirtualDub loaded default settings)
Video>filter>resize
720x272
Blackspace:
Vertical:208

File>Start Frameserve then loaded into CCE

Conclusion
When I right click on the files AVISynth and VirtualDub produced with CCE (with WinXP Pro SP1) the AVISynth says the file is 720x576 and the VirtualDub file says it is not a valid MPEG file. Also the AVISynth file is only 1.60 GB, but the VirtualDub file 3.02 GB. What is going on here? I can get both files to play fine (on the computer, haven't tried standalone) and they even look like the same quality (but they are a little dark, is there a way to do increase the brightness in AVISynth and what filter for VirtualDub?). In addition, how would i check the final fps and what would u suggest the fps?... Does CCE change to 29.97, is it necessary to change to 29.97, would it be hard to convert from 25fps to 29.97fps?
Any clues about how to resolve this bizarre conclusion would be much appreciated. Also since AVISynth was a lot faster, I would prefer getting its setting correct, this is if the quality is the same or better than VirtualDub.

Thanks for reading

[brentd49]

Is there anybody out there?

[bunyip]

Yes we're here - but some of us are in a different time-zone

The anomolies you are seeing are due to enabling the 'DVD Compliant' option in CCE and the inconsistent frame rate vs frame size that is fed to CCE.

By enabling 'DVD Compliant', CCE resizes the video to match the NTSC or PAL standard. It determines this using the frame rate. So no matter what the frame size is that you frameserve to CCE, if the frame rate is 25 then the result will always be 720x576. Similarly if the frame rate is 29.97 then the result will always be 720x480.

You can override this by disabling 'DVD Compliant' but in your case you really want to feed the correct frame rate, in AVISYNTH you can use either the 'ChangeFPS' or 'ConvertFPS', in VirtualDub you can use the 'Frame rate control' but you will have audio-sync problems in Vdub.

For brightness control use the 'Levels' filter in AviSynth or the 'Brightnes/Contrast' filter in VirtualDub.

[brentd49]

Forgot about the time-zone

So if I wanted to convert to a NTSC compatiable format.
I would uncheck DVD Compliant in CCE.
And would this script work for AVISynth? I don't want the audio out of sync and I'm going for maximum video quality.

.................................................. ...
avisource("Movie.avi")
Bob()
BicubicResize(720,272)
AddBorders(0,104,0,104)
Levels(0,1.677,230,0,255)
Convert(59.97)
SeperateFields.SelectEvery(4,0,3)
Weave
ResampleAudio(44100)
.................................................. .....

note: I'm not actually converting the audio with CCE.

[sterno]

The best way to convert a PAL framerate to an NTSC framerate is usually to just do an assumefps(23.976) to change the frame rate to FILM without actually adding or removing any frames. Since the playing time changes you'll have to adjust the audio length to match (besweet is one program that can do that for you), but playback will be smooth. After you get your MPEG2 video stream from CCE, use pulldown.exe to flag it so that the DVD player will know to telecine it to 29.97fps on the fly (this is what most commercially-produced DVDs do).

I haven't worked with laserdisc captures, but you probably will want to do some experimenting with deinterlacing methods - FILM material should be progressive because it gets telecined before going to your TV. If you can change the frame rate in some way similar to what I said above you'll avoid jerkiness. Motion usually won't be smooth if you actually change the number of frames because you're trying to throw out one frame every second.

[bunyip]

You can leave the DVD compliance option on, providing that you get the frame-rate correct.

Using a frame-rate of 23.976 as Sterno suggests is another way, in fact using the AssumeFPS option supports audio synchronisation if you use 'AssumeFPS(23.976,True)' (you might like to consider letting CCE do the audio conversion as well, because of this).
CCE will interpret 23.976 as compliant and get the frame size right.

If you want to stick with 29.97, in the later versions of AviSynth, using ChangeFPS(29.97) will pad the frames and you may or may not notice some slight jerkiness, audio adjustment will probably be necessary.

Keep the script simple - I think with your suggested method you will have a lot of trouble getting the frame-rate correct.