Re: [transcode-users] Optimal bitrate for divx->dvd

[Maik Holtkamp <s-y-l@xxxxxxx>]

Hi,

0n 04/07/15@xx:02 Marco Steinacher told me:

> I'm doing my first steps with transcode and want do burn some 
> DivX-Movies (700MB, 1.4GB and 2.1GB) on DVDs.
> 
> Currently I encode the movies with ffmpeg and transcode converts the 
> 700MB DivX files to mpegs that are about 1.2G to 1.6G. This is nice 
> because 2-3 of these movies will fit on one DVD. But I wonder if the 
> resulting movies will be of the same quality as the original DivX.
> Especially the DivX files that are 1.4G or 2.1G big and converted to 1G 
> MPEG2 files will be of lesser quality I suppose.
> 
> 
> So I would be glad to hear your experiences in this issue. Especially:
> 
> 1. What is the optimal bitrate to encode 700MB/1.4G/2.1G DivX movies to 
> MPEG2 to retain the quality but also use as little space as possible? 
> How do you do this?

It's depending on the source material. Some still pics with sound
are cheaper to encode than a Formula 1 race. They will never be of
the same quality as the original, as mpeg4->mpeg2 will reduce
quality. However, the quality difference is probably hard to
recognise with your eyes.

Further the bitrate to spend depends on the size of the pic. If the
originals are less than 720x576(480) I would consider to use the cvd
standard (probably increase the bitrate a bit, if you hardwarebox
allows it). A 352x576 mpeg2 @ 2500-3000 kbps should be fine in most
cases, playable one most standalones and meets my needs, YMMV.

> 2. What is the difference between the ffmpeg and the mpeg encoder module?

mpeg sucks. It's neither fast nore good quality. ffmpeg is fast and
good quality. mpeg2enc is best quality and slower. [FAQ]

> 3. How can I change the bitrate/quality setting of the ffmpeg or mpeg 
> module in transcode?

I use mpeg2enc and you can tweak is options in line with man
mpeg2enc at -y mpeg2enc=<here>,soundcodec or -F 4,"<here>". The
Options will be added to the command line and therefore override any
defaults set before.

-- 
bye maik

pgp00007.pgp
Description: PGP signature