Bit Rate for DVD Creation

[garywood84]

I have recorded some video onto my computer using a TV Card (Hauppauge WinTV PVR-250). It's in MPEG 2 format, with a bit rate of 6400 kbps (CBR).

I am trying to use VideoStudio 8 to create a DVD containing four such videos, each of which is one hour long. On the Create Disc wizard I have set a custom setting with a bit rate of 2250 kbps (CBR) and MPEG sound 192 kbps.

However, the completed project is unacceptable because it suffers from severe pixelation, expecially on fast moving pan/action sequences.

I can't understand why this is, because I have tested this bit rate is of sufficient quality by capturing some video from my TV card using the same bit rate values and this is not distorted in any way.

Can anyone advise me why the conversion is creating pixelation and if there is anything I can do to avoid it?

Thanks

Gary

[kebrinton]

Why go to DVD format when you're going to reduce quality to less than VHS level?

You can get DVDs cheap so why not put each hour-long item on a separate DVD and go for 6000+ bitrate?

[garywood84]

Thanks for your reply kebrinton.

I'm not sure what the quality of VHS relates to in terms of bit rates - perhaps you can advise me further?

I figured that 4 hours on a DVD wasn't unreasonable. DVDs of TV series that you can buy usually contain about 8 episodes (i.e. up to 8 hours) although they are on the equivalent of a dual layer DVD (DVD9) disk. This is why I reasoned that with half the capacity I ought to be able to achieve decent quality with 4 hours of film. Somebody please correct me if I'm wrong.

As a matter of interest though, does anyone know why the pixelation occurs? When I used to make SVCDs I never had pixelation problems, even with bitrates lower than the ones I'm talking about here.

Thanks

Gary

[hocksteo]

To all: What is the bitrate used for commercial DVD movies?

[THoff]

I varies greatly, but most Hollywood movies will be recorded using VBR at around 4000Mbps. They are encoded using 20+ pass hardware encoders.

[hocksteo]

What is the recommended bitrate to optimise and balance between quality of the video we take and amount it can fit into a DVD?

[rwindeyer]

The short answer: I don't know.
Personally, I burn my home movies - from digital camcorder - at maximum quality. (VBR, 8000). That's about 70 mins per disc, with AC-3 audio. I have also been transcribing some VHS tapes; the incoming signal is not as clear as digital video; I have found that VBR around 4000, with AC-3 audio, has allowed me to get nearly 2 1/2 hours on a disc, with identical quality to the original tape.

[ggrussell]

(720 X 480 @ 9mbps): 64 minutes Est = 4,661.1mb
(720 X 480 @ 8mbps): 72 minutes Est = 4,675.4mb
(720 X 480 @ 7mbps): 82 minutes Est = 4,677.4mb
(352 X 240 @ 4mbps): 140 minutes Est = 4,669.1mb

These are general estimates, but can vary depending on the codec being used and the audio codec being used.

[Howell]

I have found the following bit rates are applied to dvd recorded on a stand alone recorder

For 2 hours 4650 with screen size of 760 by 576
For 4 hours 222o with screen size of 352 by 576

Howell

[THoff]

Those resolutions are slightly off. For Full D1 resolution they should be either 704x576 / 720x576 for PAL or 704x480 / 720x480 for NTSC, and for Quarter D1 / CIF they should be 352x288 for PAL or 352x240 for NTSC. CIF is close enough to VHS tape in recording quality that most people can't immediately tell the difference.

Do you know if the recordings are made with CBR or VBR bitrates?

[GeorgeW]

The FullD1 resolution number does look a little off, but the Half D1 resolution numbers look correct (352x576 for PAL).

[Howell]

Sorry it should be 720
Howell

[praebo1557]

ggrussell I totally agree with yor argument.