using ffmpegx to encode 352 x 480 / 576 DVD mpeg-2

[geek rock]

i have a lot of 3-hour VHS tapes that i want to transfer to DVD, so i figured i might as well use the half-resolution DVD format (352 x 480 / 576) for the sake of making the best use of the low bitrate. obviously, being VHS, the quality won't suffer too much from using the lower resolution.

does ffmpegx do VBR encoding by default? what are the best settings to use for this? i don't mind how long it takes, i just want the best possible image quality.

at present i just select the "quick preset - lo bitrate DVD" option, and change the bitrate to 3000, and the audio bitrate to 160kbps.

i did have a play around with the quantizer settings, but they resulted in the end file size changing dramatically. i can't afford to have such huge file sizes as i need to fit the 3 hours on the DVD.

any ideas/suggestions welcomed.

thanks!

-Mark

[major]

There is no point in using a higher bitrate than the preset bitrate, for such image size. The min quantizer should be set so as mplex output of Peak bit-rate and average bit-rate differ by about 20-25%.

[geek rock]

There is no point in using a higher bitrate than the preset bitrate, for such image size.

why not? i thought as much bitrate as possible was the way to go!

[major]

For a given image size, a finite number of bits is needed to encode it to mpeg-2, depending on the quantizer value. If you exceed that value, you will just waste space on the disk.

[geek rock]

ok, thanks..

do you think i should use the default DVD resolution then? (720 x 480 / 576)

-Mark

[major]

From VHS source it will not look any better than D1 resolution (which is SVHS quality), so I would keep D1.

[geek rock]

ok, thanks.

i'm trying to get my encoded file to look as good as possible.. what image filters (if any) would you recommend?

thanks for all the help so far!

[major]

Try "denoise", and eventually "deinterlace". You can check the output quality while encoding with the "Preview" button so you can stop the encoding with apple-dot if you don't like it or want to change settings again.