[LAU] DVD creator ?

[Florin Andrei]

Dave Phillips wrote:
>>   
> AVS lets me set the video width & height, so I'm okay there. Alas, I 
> can't set fractional frame rates, so 30 FPS is what I start with.

Usually 30fps actually means 29.97, depending on the tool.

> Audio output is a 48 kHz WAV, what considerations do I have where that's 
> concerned ?

PCM can be used as an audio track on DVD, but it's a waste of space.

Encoding to AC3 is trivial. The vast majority of commercial DVDs use 
that format for audio. Just use it, it's what everyone else does. :-)
All my scripts encode the audio track to AC3, look there for inspiration.

MP2 is the third option, but almost nobody uses it.

> My current method of Kino-to-DVDStyler works, but the resulting video is 
> not good, definitely nowhere near as good as the original AVI. I'll be 
> investigating ways to improve the quality. I take it that expensive 
> higher-quality encoders are out there ?

There are many possible reasons for the poor quality. The MPEG2 encoder 
is the usual, but by no means the sole, suspect.

If the source is noisy, it may overload the encoder. After all, there 
are only so many bits available in the video stream to encode the 
information. Reducing the input by denoising may help, provided that 
noise is indeed the problem.

But yeah, often it's as easy as "use a better encoder". There are many 
professional encoders, quite expensive but quite good.

HCenc is free and good enough. I did some tests with it, using 
commercial DVDs as a source, and re-encoded the material with HCenc, 
using mild compression. Even during a direct A/B comparison, I could not 
detect any quality loss.
Also, when reducing the size of the video track, HCenc is equal to a 
good requantizer (like DVD Shrink) for small reduction factors (down to 
70% of original track size); lower than that and HCenc becomes clearly 
better than any requantizer.

That's kind of counter-intuitive, you would expect a full re-encoding to 
lose more quality than just shaving off bits with a requantizer, but the 
fact is that I tried several methods to put 3 hours of video on a single 
layer DVD and so far HCenc provided the best quality.
It's also very good when the compression constraints are not so 
dramatic, but in that case many encoders are good enough.

-- 
Florin Andrei

http://florin.myip.org/