encoding for maximum quality?

[hoder]

Is there any way of knowing exactly where to split a video file and what bitrate/resolution to encode it at so that it will fill 2 vcds completely so I can get the best possible quality on the final product?

[erandre]

When you're making VCD's there are spesific specs you must follow for it to be a VCD.

Resolution: 352x288 (PAL) 352x240 (NTSC)
Framerate: 25Hz (PAL) 29,97 (or 23,97) (NTSC)
System bitrate: 1374kb/sec

If you use a higher bitrate than this, the VCD wont be VCD-compliant, and most lightly your standalone player wont play it...

[ginoserg]

Erandre, I think you have not understood the question... Hoder ask "where to split" so I think the problem is:

- I have a video and want to encode and burn on two cdr.
- This video has a lot of action in the first half and less in the second (strange, but... maybe !)

If I cut this video in exact half and use the same bitrate I'll get a good result for the second half and a less good result for the first half. If I cut some minutes BEFORE the exact half I can use an higher bitrate for the first half, and lower for the second.

At the end I always get 2 full-CD, but with "optimized bitrate".
So, is there a way to calculate where to split ??

And my answer is:

I don't know ! It's not simple. I think you may:
- split in exact half
- encode in automatic VBR each half
- you probably get 2 different lenght mpg
- look at what mean bitrate you got in each half with a bitrate analyzer
- do a proportion to calculate final cut point.

for example:
film lenght = 120'
mean bitrate first half = 1300
mean bitrate sec. half = 1100

you do: (1300+1100) / 2 = 1200
120 / 2 = 60

1200:60=1300:x
(mean overall bitrate : half film=higher mean bitrate : X )

x = 1300x60/1200 = 65'

You must cut so that you have the "higher bitrate part" shorter.
In our example you cut first half = 55' and second = 65'.
So when you encode in CBR (or 2 pass VBR) to have 2 files that fits exactly on 2 cd, the "lot of action" film half will have more room, more bytes.

Bye.

[erandre]

Yes i understand what you mean, but if you use settings other then those i mentioned in my earlyer reply, the discs will NOT be VCD-compliant.

[hoder]

wow, it all seems so simple now!

thanks guys.