Real time encoding: Which (MPEG2/4) codec?

[ernstblaauw]

Today, i'm playing around with my Cinergy 400 TV card. I want to capture some TV-progs. I don't want big files, because I don't have time to recompress them after capturing. So I want to capture directly to a good compressing codec. I was thinking about MPEG4 (Xvid, DivX, VP6) or MPEG2.
Has anyone some experiences with capturing to such a codec, and knows the best settings? I tried VP6 6.2 (captures quite well, but only at a high bitrate) and Xvid 1.0 RC4 (which setting I triy, I get lots of dropped frames. Is it worth trying DivX? Or is is better to capture to MPEG2 directly?
I'm using the program Fly 2000 TV, but if I need another (better?) program for the best results, I will use that program.
I'm using Windows XP, and I have a AMD Athlon 2500+.
I hope someone can answer my questions.

[bond]

vp6 is not mpeg-4 compliant! its an totally own proprieatary format

i think the fastest mpeg-4 codec around is nero digital, quality should be like divx5

[ernstblaauw]

Originally posted by bond
vp6 is not mpeg-4 compliant! its an totally own proprieatary format

i think the fastest mpeg-4 codec around is nero digital, quality should be like divx5
Well, I thought is was MPEG4, but it doesn't matter. I just want the best quality, not costing too much space.
DivX is quite slow, I thought. Is it suitable for real time encoding, to use with TV capturing?
And the NEro Digital codec is not freely available, so i can't use it in any TV-caoture prog, can I?

[bond]

divx5 is also not free. with the free version you "pay" via the adware side :D

hm about how to reach the best quality with capturing, sorry i dont know much about it so i am surely not the right one to ask :(

[jggimi]

MPEG-2:

When I began capturing, I started with MPEG-2 captures with a BT878 compliant card. In order to eliminate frame drops, I had to set the GOPs so that it was 100% I-Frames (IIIIIIII....). This eliminated the extra CPU consumption of P or B frames, and had the benefit of editing on any frame.

DivX 5.1.1:

I haven't used it for capture, but it has settings specific for this purpose. See http://www.divx.com/support/guides/DivXGuide51.pdf for codec settings during capture.

[avih]

i mostely capture for pvr functionality. i used to use xvid as my main capture codec. but.

i lately capture using ffvfw, interlaced (about 4xx x 576), add some filtering to the mix (using dscaler's filter integration into ffdshow --> into ffvfw. i'm using the adaptive noise filter). the filterring allows me reduced bitrate if it's mostely static scenes. bitrate about 1200-3000 depends on the material (i.e. snooker ... motorsport). ffvfw settings tweaked a bit to allow real time capture in these relatively high settings in real time (i.e. no 4MV, etc). cpu is at about 60%-95% depending on the material. about 1 dropped frame in 40-50 secs.

for capturing i use vdubVcr (for the timer feature), using btwincap drivers on winXP-pro.

results are usually super-smooth.

for playback of these clips i use ffdshow, deinterlacing using dscaler plugin integration (usually tomsMoComp2, but sometimes bob). add some postprocessing (deblock/dering) and reclock at the background and it's practically better than most VCR's i've used.

my favorite player is zoom player (i like the skin and the tweakability, especially of the mouse wheel).

heaven on earth ;)


today i decided to download ffdshow+ffvfw from athos (2004-04-24 build). well well, my performance literally doubled :). with the settings above i now get 30%-50% cpu, i'm now able to capture 640x576 with 4mv without getting over 95% cpu :) talking about a nice build. my prev ffvfw build was from around jan-feb.

[rfmmars]

It's apples and oranges. First you have to start with a good capture card. Drop frames in MPEG2 format, NEVER! 15,000 bps I frames only 720x480 29.97fps.

Whats the secret? On board Mpeg2 chip encoding. Pichure quality? Can't tell it from DV.avi using the above settings.

A new MJPEG codec has come out from LeadTools. You can try their demo for free. To buy it, you will have to shell out $9.95 US. There are programs that won't take a mpeg2 file as imput, so with the VDF2WDM wrapper, I can use this very flexable-fast codec.

All this is done with a ATI 9000 AIW card $179.95 US

richard
phororecall.net

[Malow]

matrox mpeg2 i-frame avi codec