Resolutions affect vcd quality?

[jowo77]

Sorry for this noobie question but if I burn an mpg file that is 320x240 as opposed to a mpg that's 640x480, will it look worse when I burn it to a vcd? Meaning when I watch it on my VCD player and TV.

[Anonymous65]

A VCD is 352x240 @1150 kbits/sec, nothing else. The bigger frame size, the better resolution, the better the image quality. If VCD is not good enough, then try SVCD or non-standard VCDs.

[holistic]

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On 2001-11-25 22:23:25, skittelsen wrote:
The bigger frame size, the better resolution, the better the image quality. If VCD is not good enough, then try SVCD or non-standard VCDs.

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Hmmm YES and err NO . If you increase the frame size (resolution) then you need to vastly increase the bitrate.
640*480 IS 4 TIMES bigger than 320*240 therefore if you keep the same bitrate there will be less (bits) data to distrubute.
In simple terms : MPEG works by updating the data as it changes . So for example if you have a 1 cm square move across the screen then a 4cm square (4* don't forget) the image quality will not look as good if the bitrate remains the same .
*thinking* - an anology - take a penny ( 1 cent) it has X surface area. Now picture it after compressed under say a train wheel (don't do this at home ) . Same coin bigger surface area . Less quality !
I know skittelsen knows this but it seems it is a concept people have trouble with.

[mikk]

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On 2001-11-25 22:23:25, skittelsen wrote:
A VCD is 352x240 @1150 kbits/sec, nothing else. The bigger frame size, the better resolution, the better the image quality. If VCD is not good enough, then try SVCD or non-standard VCDs.
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PAL VCDs are 352x288 x25fps. that's 20% more than NTSC. FILM is 352x240 x24fps so it has the highest number of bits per pixel, so the image is less blocky. pick between PAL and FILM unless u're dealing with an NTSC 30fps source.

[eqix]

I created a VCD but I was very disappointed with the quality. I was expecting VHS quality and got Internet quality, unles VHS-quality stands for VHS quality of a copy of a copy of a copy .

I used Pinnacle Studio DV 7 to render the MPEG and Roxio CD Burner Platinum to burn the VCD. Can anybody recommend a good MPEG renderer?

Thanks,
Jesus Barrera

[Panash]

quote
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Sorry for this noobie question but if I burn an mpg file that is 320x240 as opposed to a mpg that's 640x480, will it look worse when I burn it to a vcd? Meaning when I watch it on my VCD player and TV.
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The higher vertical resolution is usually to support interlace in MPEG2, which you won't get in MPEG1 VCD. So improvements will probably be limited by your TV. VCD doen't look quite as smooth as properly interlaced MPEG2 (but probably quite acceptable - certainly to your grandmother) Stay with the VCD standard, it is the best set of compromises.

PN

[shardison]

If you capture at 640x480(at 3500kbs or so) and then convert/compress to VCD resolution, it will look like there are more details,(and thus look better) than if you do a direct capture to VCD resolution at any bitrate.

The difference is noticable on a computer screen, but not so much on a small TV.

Did that answer the question?

[Truman]

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On 2001-11-26 07:18:46, mikk wrote:
PAL VCDs are 352x288 x25fps. that's 20% more than NTSC...
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That's not really true, because you missed a part of the calculation.
PAL: 352x288x25=2534400 pixel/sec
NTSC: 352x240x29,97=2531865 pixel/sec