DVD Demystified - Part II

On popular request, here’s the sequel to my DVD Demystified. In this issue, I’ll be telling you about special formats and give you an idea of the read/write speeds of different DVD media.

~~~~~Special Formats~~~~~

DVD-VCD
It is basically a VCD authored on a DVD. DVD supports the VCD resolution but the audio is changed to 48 kHz - the DVD standard. Although, this allows you to store very long movies on a single disc, very few players (except your computer) support it.

DVD-SVCD
It is an SVCD authored on a DVD. DVD does not supports the SVCD resolution but it may anyway(in some players) and the audio is changed to 48 kHz like the DVD-VCD. Once again, very few players support it.

DVD-MP3
It’s nothing but MP3s burned on a DVD but very few MP3 capable standalone DVD Players supports it because most Players verify DVD as DVD-Video only.

DVD-ISO
It is MPEG, MPG, VOB files burned on a DVD without any DVD Authoring(making the vob, ifo file, like just burning the .DAT file onto a CD instead of properly authoring a VCD) but very few standalone DVD Players supports it as most Players verify DVD as DVD-Video only. Almost no player in the Indian market supports these either.

You can use this searchable online DVD player database to see which player is compatible with any of these special standards mentioned above and more.

~~~~~DVD Read and Write speeds~~~~~

Don’t think that 16X writing speed in a DVD is the same as 16X speed in a CD. 16X in a DVD is almost 400X for a CD, speeds that no CD-Writer can provide. You can use the tables given below to approximate read and write speeds and their corresponding times

Single Layer(4.7GB) write speeds
1x (CLV) = about 58 minutes
2x (CLV) = about 29 minutes
4x (CLV) = about 14.5 minutes
6x (CLV/ZCLV) = about 10-12 minutes
8x (PCAV/ZCLV) = about 8-10 minutes
12x (PCAV/ZCLV) = about 6.5-7.5 minutes
16x (CAV/ZCLV) = about 6-7 minutes

Dual/Double Layer(8.5GB) write speeds
1x CLV = about 105 minutes
2.4x CLV = about 44 minutes
4x CLV = about 27 minutes

Single Layer (4.7GB) read speeds
1x read speed is 1.321MB/s = ~56 minutes
6x CAV (avg. ~4x) read speed is max 7.93MB/s = ~14 minutes
8x CAV (avg. ~6x) read speed is max 10.57MB/s = ~10 minutes
12x CAV (avg. ~8x) read speed is max 15.85MB/s = ~7 minutes
16x CAV (avg. ~12x) read speed is max 21.13MB/s = ~5 minutes

Speeds show minor variation depending on which access system your drive uses - CAV, CLV or ZCLV

And in case you found this article more boring than Part I, then don’t worry, Part III will deal with the anatomy of a DVD-VIDEO disc, a much more interesting topic.