The Last and Final Word: VHS-MPEG-2

[macm]

after dozen of books and articles (after all, this is my Master Degree thesis!) and for your information:

"
How does MPEG video really compare to TV, VHS, laserdisc ?

VHS picture quality can be achieved for source film video at about 1 million bits per second (with proprietary encoding methods). It is very difficult to objectively compare MPEG to VHS. The response curve of VHS places -3 dB at around 2 MHz of analog luminance bandwidth (equivalent to 200 samples/line). VHS chroma is considerably less dense in the horizontal direction than MPEG source video (compare 80 samples/ line to 176!). From a sampling density perspective, VHS is superior only in the vertical direction (480 lines compared to 240), but when taking into account interfield magnetic tape crosstalk and the TV monitor Kell factor, not by all that much. VHS is prone to timing errors (which can be improved with time base correctors), whereas digital video is fully discretized. Pre-recorded VHS is typically recorded at very high duplication speeds (5 to 15 times real time playback), which leads to further shortfalls for the format that has been with us since 1977.

Broadcast NTSC quality can be approximated at about 3 Mbit/sec, and PAL quality at about 4 Mbit/sec. Of course, sports sequences with complex spatial-temporal activity need more like 5 and 6 Mbit/sec, respectively.

Laserdisc is a tough one to compare. Disc is composite video (NTSC or PAL) with up to 425 TVL (or 567 samples/line) response. Thus it could be said that laserdisc has 567 x 480 x 30 Hz resolution. The carrier-to-noise ratio is typically better than 48 dB. Timing is excellent. Yet some of the clean characteristics of laserdisc can be achieved at 1.15 Mbit/sec ( SIF rates), especially for those areas of medium detail (low spatial activity) in the presence of uniform motion. This is why some people say MPEG-1 video at 1.15 Mbit/sec looks almost as good as Laserdisc or Super VHS.

Regardless of the above figures, those clever proprietary encoding algorithms can push these bitrates even lower.
"

So, the bets bet for MPEG-2 capture/encode is (from VHS sources):

352x480 @6Mb. No B frame is needed, if you want best quality (perhaps with a sligth increase in size. But it is worth)

ANYTHING outside those range is waste.

[macm]

Another information:

2-pass VBR is still inferior in image quality to CQ mode. This behavior is consistent with that of other encoders, so I can only conclude that the CQ algorithm is inherently superior.

so, 2-pass VBR is a complete waste of time/resources. Use CQ and you will see the results (the best one....in quality!!!!)

[Gazorgan]

Now if only CQ can hit a predicted file size...........

[macm]

Yeah,

that's the idea. If you want HIGH QUALITY instead of SMALL FILE SIZES!!!

Just try a little, and see.

Even with VBR or CBR, you can only predict a file size in average. Never predict it with accurancy.

But if you only want to put as much as video into a DVD, it's up to you.
Then, degrade the quality as much.