Reducing AVI/DivX file sizes

[webstar]

please could someone post simple instructions as to how i can use ffmpegx to reduce the size of AVI or DivX files so that they fit onto a 700MB CD ?

i have several files that i've downloaded that are 700-850MB in size & i would like to fit them on individual cd's. i don't mind a slight loss in quality.

whenever i try to do this, i either end up with a larger file that i started with or else there are other problems or failures.

thank you very much.

mark

[tomlee59]

whenever i try to do this, i either end up with a larger file that i started with or else there are other problems or failures.

Can you describe more specifically what you tried that didn't work? It will help us help you if you say more than "what I wanted to happen didn't happen."

[webstar]

i may have to eat humble pie - i ran a test last night so that i could explain myself more clearly, and it actually worked fine.

this is what i did ...

dropped the original file into ffmpegX.

the original was identified as mpeg4, yuv420p, 720x536, mp3, 44100 Hz, stereo, 192 kb/s, 80 minutes long.

ffmpegx automatically selected the MPEG4 [.AVI] mencoder.

i changed the parameters in the audio tab to be the same as the original.

in the video tab i checked that the video size and framerate were the same. i selected the running time (80 min) keep in 1 CD of 80m mode-1, 700MB. pressed the "rate" button and it calculated a bit rate of 1014kbit/s.

i pressed encode.

have i done this correctly ? are there any other parameters i should have checked or changed ?

though the test AVI was only reduced by 11.6MB, to make the 703MB original burn on a single CD, there was a marked increase in blocking of darkly shaded areas. i would be interested to know if that effect could be reduced at all ?

thanks,

mark

[webstar]

unfortunately this story doesn't have a happy ending. when playing the ffmpegx compressed avi in vlc the image kept freezing. i've tried burning two cd's and neither will play in my dvd players (which can and have played dowloaded avi files i've burned in the past). a strange thing happens - only the top half of the image is read from the disc & the bottom half of the screen is frozen on the dvd players default screen. i've tried it in two players. (both toshiba)

has anyone else experienced this, or know a way to fix it ?

thanks,

mark

[jpschuck]

the original was identified as mpeg4, yuv420p, 720x536, mp3, 44100 Hz, stereo, 192 kb/s, 80 minutes long.
[…]
though the test AVI was only reduced by 11.6MB, to make the 703MB original burn on a single CD, there was a marked increase in blocking of darkly shaded areas. i would be interested to know if that effect could be reduced at all ?

In that particular case you had better leave the video as is (passthrough) and only re-encode the audio part to 128 kb/s (or 160 kB/s). On a 80 min clip, it would save about 30 MB (or 15 MB).

[webstar]

jean-philippe

thank you very much for this tip - it worked with passthrough and 160 kB/s audio.

cheers !

mark