|
|
Posted by Bill Lee on 10/05/08 11:38
In article <1138581319.764400.174900@f14g2000cwb.googlegroups.com>,
"Paul Turner" <turnerpaul@gmail.com> wrote:
> ok, so I've spent ages in Premiere and I'm lef with 8 movies for the
> dvd I'm making. the thing is, after I've exported them (at avi/dv
> codec settings) all 8 files come to 22gb!
22GB is about one and a half hours of DV video, using the rough rule of
thumb of 14GB per hour for DV. If you know the exact sum of the minutes
of video you can feed it into the following calculator:
<http://www.videohelp.com/calc.htm>
> What's the easiest way to reduce the size, without losing quality, so i
> can fit them on a 4.7gb dvd?
If you are making the video for a DVD then you'll need to transcode your
DV Codec encoded video into MPEG-2 codec video. Transcoding will lose
quality - the question is: "How much, and will it be noticeable?" The
less compression you have to do, the less quality should disappear in
the process.
A good place to start is to look at the DVD Authoring package you are
going to be using. Make sure it will support the MPEG-2 that you are
going to feed it, as well as the type of audio you are going to feed it.
If you don't have a lot of extras (menu animations, subtitles, alternate
angles, or alternate audio tracks), then you should be able to get by
with a 'reasonable' MPEG-2 encoder, which should give OK results for
6Mbits per second target rates. Encode your Audio as Dolby Digital
instead of PCM, as this will give you an extra megabit per second to
allocate to your video. Some encoders have Variable Bit rate encoders
(VBR) which, although taking longer to encode than Constant Bit Rate
(CBR), usually are more efficient in their use of your available bitrate
(it depends also on the source material). Be aware that the instant
peaking of bitrate on some VBR encoders may exceed the nominal limit of
the maximum bit rate, and that depends on the transcoder (RTFM if you
experience problems with overly high instantaneous peak bitrates).
Since I work with Macintoshes, I'll not attempt to answer exactly which
PC software transcoder to use, but at the bit rates that you are
proposing, there should be a reasonable number that will give you the
desired quality. If you had to fit twice as much video on your DVD it
would be much more difficult and expensive answer to your question.
Another thing to keep in mind is that more bits is not necessarily going
to give you increased quality. Keep your combined video and audio to
less than 9Mb/sec (8.5Mb/sec is better) to improve playback quality,
especially on some cheaper DVD players. This would apply when making
shorter DVDs, where you might be tempted to up the video bitrate to
9Mb/sec and leave the audio as PCM, which would drive the overall bit
rate to about 10.5Mb/sec - this disk will fail on a number of DVD
players.
Bill Lee
Navigation:
[Reply to this message]
|