Hi

This is my first post to this forum and I am a relative newbie to the making of VCD's.

Several questions have arisen and I can not find satisfactory answers to and I was hoping some guru here maybe able to help. Firstly in virtualdub/Nandub what is the difference between Direct Stream Copy and Full Processing Mode? I am not quite sure what the Direct Stream Copy option does.

Also It is my understanding that when making a compliant PAL VCD in TMPGenc that the video should be set to 352x288 1150kbps CBR and (if using an mp3)audio to CBR@224kbps via one of the templates. However I have seen in several threads and on other forums that some are using CQ_VBR. Is VBR compliant?

Last question if I create a DIVx from DVD and in turn that DIVx is going to be made into VCD, am I better off creating the DIVx at 352x288 at a high bitrate?

Thanks if you can clear this up for me.

steve

-- Steve (ghobbit@paradise.net.nz), April 23, 2002

Answers

I don't know the answer to your VirtualDub question. White Book says the video bitrate of a VCD is ALWAYS a CONSTANT 1150kb/s. Some have successfully used higher bitrates, but as it is ALWAYS MPEG-1 it follows it is CONSTANT bitrate. So, NO, a compliant VCD is NEVER VBR. If you really want that there is SVCD, which uses MPEG-2 (VBR or CBR, with a peak bitrate total of about 2600kb/s). Constant Quality is a feature of MPEG-2, which CAN BE and is nearly always used VARIABLE bit rate. It is always best to create a VCD from the highest resolutions you can start with. For example, given the option to store an AVI at 720x576 or 360x288, as long as I had space, I will take the first. Later on TMPGenc will produce smoother (NOT softer) results with more lines to interpolate and de-interlace with (choosing the right de-interlace options) compared with just starting with 360x288.

-- Mehmet Tekdemir (turk690@yahoo.com), April 24, 2002.

one more thing to add to mehmet's message.

mp3 is not a compatible vcd audio format.

-- phi pham (phipham@yahoo.com), April 24, 2002.

Thanks for your replies.

I understood mp3 was vcd compliant so long as it was CBR and VBR certainly as far as TMPGenc because it doesnt like VBR mp3's.

Ive been using CBR mp3's with TMPGenc and they sound fine - no sync problems

cheers

Steve

-- steve (ghobbit@paradise.net.nz), April 25, 2002.