MPEG Video bitrate?

lionround · Post by **lionround** » Fri Aug 05, 2005 1:12 pm

All,

I am trying to capture 2 hours of MPEG1 to a single CD. That translates to a bitrate of about 745 kbps. However, the lowest bitrate that the software will allow is 1150. Is there a way to adjust this during the video capture (much preferable method) or can I render it down after capturing (much less preferable and too time intensive)?

Thanks.

heinz-oz · Post by **heinz-oz** » Fri Aug 05, 2005 1:49 pm

What are you trying to do with this file after you are finished?
The VCD standard is 352 x 288 frame size (PAL) at a bit rate of 1152 kbps. Anything other than that is not going to play on a DVD player.

At that bitrate, the resultant quality is not something to get exited about, less than VHS, like a copy of a copy. If you lower the bitrate even further, what do you expect to get?

If you want to use it for streaming to the web, that is a different matter. I just don't know about that because I have never done it. In any case, I don't think DVD MF would be the right software to create streaming media.

lionround · Post by **lionround** » Fri Aug 05, 2005 1:57 pm

I am not trying to get DVD quality. I am trying to digitize VHS videotaped depositions that will be displayed through a projector onto a big screen. The purpose is that the Judge and jurors can see the person speaking. That's all. However, I need to try to get 2 hours onto a CD because the standard still being used by most legal videographers is VHS or SVHS. Quality is not the issue; file size is.

Thanks.

AnimeChick · Post by **AnimeChick** » Fri Aug 05, 2005 3:31 pm

You can't adjust the data rate on a VCD like you can with a DVD. I'd suggest burning the video to a DVD. Video Formats

maddrummer3301 · Post by **maddrummer3301** » Fri Aug 05, 2005 8:50 pm

How do you plan to play the material back while in court?
On a laptop computer connected to a projector or a dvd player etc.
Does it have to be a CD? Maybe a data CD with the video on it etc.

MD

lionround · Post by **lionround** » Fri Aug 05, 2005 10:05 pm

We play the video in court off a laptop computer. We store the video on an external hard drive, usually USB 2.0. I have had trials with as much as 1000 hours of video. That is close to 1TB of storage, thus the attempt to minimize file sizes as much as possible. The software we use for playback uses only MPEG1 at the present time. We synchronize the video to the transcript so the deposition plays back "closed captioned" and it makes the video text searchable pre-trial.

The purpose of the CD is really only a means of transferring the media from one place to another. We get the VHS tapes from the law firm and return their finished product on CD. I guess I can go DVD with 5-6 hours on it if need be.

maddrummer3301 · Post by **maddrummer3301** » Sat Aug 06, 2005 4:54 am

MovieFactory version 4 can do this using the EXPORT feature.

Or you can use VideoStudio9 and record directly at a low bit rate
such as 450kbs. Mpeg1 does have a lower limit for capturing approx 400kbs in ulead.

You said approx 745kbs which is correct but that would have to be the Total_Bit_Rate.
You need to include the audio in that so using 1/2 the bitrate of VCD will yield 2 hours
of mpeg1 video. 1150/2, that's squeezing it. I would give some bufer there and go lower.

Using MF4 I just captured in VCD format and exported the video as an mpeg1 video
with a video_bit_rate of Constant at 450kbs, audio was 16bit 44,100 at 128 or 224.

Do you have MovieFactory 4?
If so I can post how i did it. The down conversion does take some time to accomplish.

If you don't have MF4 then VideoStudio9 would be more suited since you can capture
direct mpeg1 500kbs etc. With VideoStudio9 you can also edit/cut/paste and change
the video(s) to various formats.

MD