I have a p3-866 30g+20g, 768m, ati rage fury pro. I have a question about settings when I capture the video.

After I open the ati multimedia centre, VIDEO IN, to capture the video, I can set up such as 'frame sequence in the MPEG output stream', 'video bit rate', 'motion estimation search ranges'.

My question is what number I should use to get better quality, especially the BIT RATE.

What happened to me is that when I set the video bit rate to 7m/s, the color of video I captured is changed all the time and the motion is stagnated and not smooth as the original. When I set the bit rate to 3m/s, everything seems fine. I am wondering if the quality is decreased even though I did not notice it.

I do not know what is the the best or minimum VIDEO CAPTURE BIT RATE setting, 3m/s, 5m/s or how to determine it. This is all happened during video capture before coding.

I opened the ati multimedia center and ran the system compatibility check and it told me in Memory bandwidth results: video read in byte is 2.91 mb/sec. Is that mean that I can only set the bit rate less than 2.91m/s.

-- David (davidx58@hotmail.com), January 17, 2004

Answers

I can give some general recommendations, but for more in depth ATI questions, please consider going to the video forum at http://network54.com/Hide/Forum/70438 I haven't used my ATI card for video capture in years because I felt at the time that Dazzle made a superior product. The memory bandwidth has nothing to do with bit rate, so ignore that. One of your problems may be the resolution you are capturing at. With your PC, you won't be able to capture at 720x480, which is the resolution of DVD. ATI does software encoding and your PC is not powerful enough to capture at 720x480 without dropping frames. 480x480, which is valid for SVCD, or 352x240 (VCD) will work fine. 640x480 will also work, but this is not a valid resolution for VCD, SVCD or DVD and you will have to encode it this video to a different resolution.

I would recommend setting "motion estimation search" as high as possible. The frame rate is probably best if it is IBBPBBPBBPBBPBB. Other settings are OK, but generally this is best for compatiblity with DVD, which you may want in the future.

As far as bit rate goes, the higher the bit rate, the better your video, but VCD and SVCD both have limits. VCD must use a constant bit rate of 1115 Mbps. SVCD can use constant or variable, but the video bit rate can't exceed 2600 Mbps and the combined audio+video bit rate can't exceed 2723 Mbps. Be careful with your card because ATI cards are known for exceeding the maximum bit rates with SVCD and this can cause audio sync problems. If you keep the video bit rate to 2200 or 2300 you will probably be OK.

http://www.vcdhelp.com has some guides on making VCDs and SVCDs that might be of use to you. If you don't care about burning what you record to CD-R and watching it on a DVD player, then just record with as high a bit rate as you like. Anything over 9000 is overkill though.

-- Root (root@yahoo.moc), January 19, 2004.

Thank you very much for your information and experience.

Per you mentioned, 'As far as bit rate goes, the higher the bit rate, the better your video, but VCD and SVCD both have limits. VCD must use a constant bit rate of 1115 Mbps. SVCD can use constant or variable, but the video bit rate can't exceed 2600 Mbps and the combined audio+video bit rate can't exceed 2723 Mbps. Be careful with your card because ATI cards are known for exceeding the maximum bit rates with SVCD and this can cause audio sync problems. If you keep the video bit rate to 2200 or 2300 you will probably be OK.'

question #1: according to your answer, when I capture the video, I can set the bit rate higher, eg 6000/s, then when I encode it, I set the bit rate to less than 2300. Is that what you mean?

question #2: when I capture the video, if I set to capture MPEG2, then when I try to encode it, the TMPGEnc will not recognize the file .mp2 which is the only type I can save. How to change the type or fix it. So what I do is: first capture in MPEG-1, then encode it to SVCD, I just want to know if it is OK or anyone is doing this too.

Thanks for help

-- David (davidx58@hotmail.com), January 19, 2004.