encoding '4:3' pal material

[smok3]

i made a few quite subjective tests to see how the downsized pal video fits the computer screen, i used the resolutions as reported by gknot 0.27 (itu checkbox doesnt seem to make any change), i came to this small list (also only the values that are dividable by 32 in both x and y axis):

http://users.volja.net/smoker/pub/pal_divx_resolutions.txt

what i wonder is what are your prefered 'fullscreen' encoding resolutions?

[DJ Bobo]

It's not like that, x should be a multiple of 32, y should be a multiple of 16, for maximum compatibility with all graphic cards, so:

320x240
384x288
448x336
512x384
576x432
640x480

[smok3]

Originally posted by DJ Bobo
It's not like that, x should be a multiple of 32, y should be a multiple of 16from what i read there is compression optimum when both sides are dividable by 32, also there are some matrox (maybe some other as well) cards that need that kind of ratio as well? wrong?

[DJ Bobo]

compression is optimal with values divisible through 16

some matrox (and some others) require x = multiple of 32

[smok3]

just for info:

looking around official divx site, there seems to be a lot of 4:3 material encoded in 512x384 (and less in 640x480 <- i guess that could be quite a playback problem for older cpu's?)

http://www.divx.com/movies/

[DJ Bobo]

yes, 640x480 is a problem for older CPUs. My P3@667 (with 133mhz fsb) can play it fine when the bitrate is not very high. Some friend of mine has a P3@750 (with 100mhz fsb) and he can't play any 640x480 video smoothly! but 576x432 works fine for him.

anyway, 640x480 needs high bitrates to achieve really good quality, that's why usually 512x384 is being used, which helps lowering the average quantizer, thus increasing the picture quality.