Jerky 23.97 fps DivX avi to 25 fps PAL SVCD ?

[ajl]

Hi all,
maybe you can help me with my problems:
I converted a divx avi with 23.97 fps to a pal svcd with the following steps (from the tutorial in the convert section):
1/ Virtual Dub extracts the audio data into an uncompressed WAV file
2/ TmpgEnc (version f, g or h, I can't check that now) to convert video and wav to PAL SVCD (using constant bitrate of ca. 2200)
3/ Write the resulting MPG using Nero 5.5.2.4
4/ Playback in my Philips 701 DVD player

Problems:
1. The picture is a little jerky/choppy (stops for some ms every 2-4 seconds). Could this be due to the difference in frame rate source <-> destination? How to fix this? Is the Pulldown option in TMPGEnc useful to avoid this?

2. The diplayed playtime is much shorter than the actual duration of the file (player shows 36 minutes, file is about 55 minutes long). The seconds on the diplay also seem to pass slower (15 secs real-time is 10 secs display-time), so I guess this is just a cosmetical thing, but how can it be fixed?

3. FF/Rew doesn't work, so I will try the methods using
a) VCDImager
b) scandata.dat (Nero fix)
c) GOP Header every 1 frames (TMPGEnc)
d) Demux and then Remux with BBMpeg
Could anyone point out the "best" method in terms of standard compliance? I don't want a SVCD that I can only play on my player now, but one that is playable everywhere

4. What is the use of the interlaced/non-interlaced option in TMPGEnc? Do I have to bother with my "standard" process of AVI/DivX -> SVCD?

Thanks a lot in advance,

Achim

[willem]

I can help you with problem #1. I had the same problem, but by checking out the different posts on this message board I figured out how to fix it. I've posted this method before but edited it with later findings.

Here's how I do it:

1 Open the DivX avi in VirtualDub
2 Select File -> Save Wav
3 Save as a file with the extension .mp3 this allows CoolEdit to recognise it as a MP3 and not plain WAV. I've seen CoolEdit only opening the first 16 mins. instead of the whole 90 mins. because it had the .wav extension.
4 Select Audio -> No audio
5 Select Video -> Direct Stream Copy
6 Select Video -> Frame Rate -> Specify Frame Rate of 25 fps
7 Select File -> Save as Avi
8 Save as a .avi file
9 Close the DivX file in VirtualDub (File -> Close)
10 Open the 25fps video stream you've just saved.
11 Go to the end of the film by pressing Ctrl + -> (right arrowkey)
12 Go back one frame by pressing <- (left arrow key)
13 Note down the duration which is shown on the bottom near the frame number.
14 Close VirtualDub

You now have a smooth 25 fps video stream ready to be multiplexed with the audio stream. The audio stream is 4% longer (25/23.976) so if you multiplex it now you'll have audio sync problems that increase towards the end of the film. Next step is to speed up the audio stream by 4%. The human ear cannot hear this difference so don't be afraid that your favourite stars sound like the Chipmunks. Here's how you speed up the audio half of the film:

1 Open the .mp3 file in CoolEdit 2000
2 Select Edit -> Select entire wav
3 Select Modify -> Time/Pitch
4 Enter the duration in seconds, CoolEdit will calculate the percentage; this should be about 4%. Preserve pitch and low precision (this may affect sound quality of music parts a bit, but won't affect dialogs. If you choose high precision it takes about 10 times as long to compress).
5 Start the conversion by pressing OK
6 When finished (takes a while with high precision):
7 Select File -> Save copy as
8 Save as a Windows PCM file (.wav)
9 Close CoolEdit

This gives you a audio file which is as long as the 25 fps video stream (check this before multiplexing). Multiplexing is next:

1 Open TMPGEnc
2 Select new project
3 Select Load -> Choose Video CD (PAL).mcf
4 Press the Browse button for your video stream
5 Select the 25 fps .avi from step 7 in VirtualDub
6 Press the Browse button for your audio stream
7 Select the .wav file from step 8 in CoolEdit
8 Choose an output filename (.mpg)
9 Press start

Now you have a PAL VCD compliant mpeg1 stream. Check if there are any audio sync problems by skimming through the file using eg. Windows Media Player. The only problems I've seen using this method were with DivX films that were not 100% OK (corrupted frames). The corrupted frames can be cut out with VirtualDub.
You probably wan't to cut the MPEG1 stream in half so it will fit on two CD's. I use TMPGEnc for it (MPEG tools -> Merge/Cut). I've tried cutting it in VirtualDub before the conversion to 25 fps, but then the second half had audio sync problems. After cutting burn it to CD using eg. Nero.
This is how I create VCD that can be played on my standalone DVD player without the one second stutter. I use VirtualDub 1.4d, TMPGEnc 12e and CoolEdit 2000.

Hope this helps.

[willem]

The "HowTo" I've posted here deals with VCD. I suppose if you select the PAL SVCD template in TMPGEnc it will work for SVCD's too.
Please let me know what the results are if you try it for SVCD. By using the templates in TMPGEnc you'll have compliant (S)VCD's that should play on most DVD players. Most standalone DVD players handle VCD fine but not always SVCD. I noticed that for my Marantz DV4100 (Philips inside?) I have to go into setup and select "PCM only" under digital audio in order to get sound from my SVCD. Otherwise it's only video. VCD's and DVD's play fine using the setting "All".

[Sturchill]

I do the Conversion from DiVX to SVCD only with TMPGEnc and Sefy`s SVCD Template. I satisfied with the End-Product. No stocking at all. I have an Philips DVD 751 standalone.

Cya

Sturchill