Bitrate for capturing mpeg2

vbimport

#1

I’ve been using my Winfast 2000 XP Deluxe to capture tv programs in dvd format mpeg2 files. The standard setting for this is 720 x 480, 6000kbps. This has been working well, and I have the tools necessary for editing out commercials, building menus etc, so I really have no need to capture in another format.

My real question is, will increasing bitrate help the quality of the mpeg files? I can increase the bitrate up to 8000 or so without any problems in the playback so far, though when I experiment with these settings, I haven’t been capturing for a long period of time. Will there be more problems by increasing the bitrate, audio sync for example? Or will this simply make larger files to no purpose?


#2

Hi Kerry56,

If you increase the bitrate above 6000, it serves no purpose since the captured file has a Bitrate of 6000, the video so captured is 6000, there will be no improvement in quality above this setting in the final output. Nothing will happen to the sync and stuff but the final output will be better than say a 2000 Kbps video file output.

Hope this helps.


#3

Hmm, I don’t think I was clear enough in my first post. The stock settings for capturing a dvd compliant mpeg2 file is, as I said, 720 x 480 6000kbs using the program that came with my card. I can manipulate the capture program so that it CAPTURES at 8000kbs, if I choose to do so. I’m just not sure this will improve the quality of the captured video over the stock setting, or if it will introduce new problems or if it is simply spinning my wheels to no real purpose.

Thanks for the reply though.


#4

You will get better quality at capturing at 8000kbs especially if there are lots of fast scenes in your video. There should be no problems in the playback when you have created your dvd. Only drawback I can see is that with higher bitrate you will get less video on a disc. Maybe around 1 hour 10 minutes for 8000kbs compared with about 1 hour 30 minutes for 6000kbs


#5

Hi Kerry56,

Asid’s right. Since you can capture at 8000 kbps the final output will be better than 6000 Kbps, but here’s the catch "Whether the improvement in quality is worth the sacrifice in terms of final video size. Since you capture directly to Mpeg2, assuming you have an average bitrate of 6000 kbps, an increase of the bitrate to 8000 kbps will increase the size of the video by 33% and lead to a reduction of the size(in time) that can fit on a DVD by 25%. The similar case can be done in a comparison of 2000 and 6000 Kbps. Increase in size of 200%(reduction in video time on DVD by 66%). So its entirely upto you, whether the material is worth the size OR the quality.

Hope this helps.


#6

Ok. Thanks guys. At the moment I can put two 1hr programs on one dvd. Increasing bitrate will mean a lot of wasted space, with only 1 program per disk, so I’ll probably keep recording at stock speed. But good to know I can increase bitrate if I need it without causing problems in the recording.