Understanding video file properties and relation to DVD/CD ROM/VCD etc.

It's my understanding that DVD holds a max of 4 gigs, correct?

After doing a mere 45 minute capture, at what I thought isn't a
paricularly high bit rate, I end up with a whopping 6 gig plus file,
and even before compression the resolution doesn't blow me away,
presumably compression reduces the image quality even farther. So, how
do they cram what looks like a very high resolution 1 1/2 - 2 hr movie
on a single DVD? Surely they must have to compress the stew out of it
to get it to fit.

What are the specs for a typical commercial DVD file? Bitrate, frame,
dimensions, etc.

Also, what's the difference between capturing something as a VCD as
opposed to just burning an mpeg video file onto a CD rom?

 

A "DVD-5" (single-side, single layer) holds about 4.7 GB.[1] There are other
formats, most commercial DVD movies arrive on a "DVD-9" which is single-sided
and dual-layered.

Better (clean) source, better (expensive) compression program.

Most parameters are standardized, read the DVD FAQ[2] for more info.

Some extra folder/files with metadata for standalone VCD players.

[1]: http://www.timefordvd.com/glossary/GlossaryD.shtml
[2]: http://www.dvddemystified.com/dvdfaq.html

 

After doing a mere 45 minute capture, at what I thought isn't a

Some lossy codecs are quite good at 4-5:1 compression. IMHO MPEG-2
looks great at 20:1. (you can take >200Mbit/sec uncompressed SDI down
to <10Mbit/sec MPEG-2 with little visual loss of quality)

Bitrate is typically VBR, with the average around 3-6 Mbit/sec, though
higher in some parts. Hollywood DVD releases make very careful use of
bitrate allocation to keep the average low without destroying image
quality.

Also consider that most film releases are encoded at 24fps, not 30fps,
which gives you a 20% savings right off the bat.

NTSC DVDs are always 720x480 pixels with 4:2:0 Y'CbCr color, at either
30/1.001 fps or 24/1.001 fps (in which case the DVD player performs
3:2 pulldown on playback). Wide-screen movies are usually encoded
anamorphically (the DVD player stretches the image appropriately for
4:3 or 16:9 displays). Audio is usually 5.1 channel Dolby Digital,
although other audio streams can be added (stereo Dolby Digital, DTS,
PCM, etc).

A DVD is more like a small website than a single file, in that most
DVDs include menus and a bit of software code for handling the menu
and remote control buttons.

Regards,
Dan

 

Roughly 4,700,000,000 bytes.

DVD-Video sets the maximum bitrate for audio and video to about 10
megabits/sec. DVD-Video supports a bunch of frame dimensions,
720x480 is the largest and probably the most common.

It's exactly the difference between burning an audio CD as opposed
to burning a bunch of WAV files onto a CD-ROM. Basically, VideoCD
formats MPEG audio and video data, as well as some navigational
data and optionally some ISO9660 formatted data onto a CD in a
specific way. The MPEG audio and video has to be encoded with
specific parameters.

Sam

 

Thanks for the info. Btw, are you any relation to Dusty Paik, the chic
in the Mitsubishi commercial?

 

I don't think so.