DIVX Bitrate / resolution?

[LanEvo7]

I am currently converting a series that I have capture off my vcr. I capture the series in mpeg2 with 640x480 resolution. Each episode is about 45 min long. I would like to be able to fit at least 2 episodes on each 80min disc. What is the best setting for that(bitrate / resolution)? I have tried the bitrate calculator on the vcdhelp site and the pictures come out blocky. I know there is a setting where you can put at least 2 hours of video onto a cd and still have sharp pictures because have THE MATRIX encoded(not by me) in Divx and the picture is very nice. The file fits on a 80min CD.

[i-on-s]

Try using a res of 640X272 and are you encoding CBR or VBR? probably be better to use a 2-pass VBR than CBR..also try VBR audio also that might help with the sizes. Try XVID also instead of DIVX just a suggestion.

hope this helps.

good luck.

[LanEvo7]

What is the difference between VBR and CBR?

[i-on-s]

it uses a min and max bitrate instead of a constent fixed bitrate allowing in smaller size. cause a movie isnt 1 bitrate all the time (not even DVD) it uses a min bitrate and a max bitrate to figure out which scene need more bitrate too look good and what scenes need less to look good (like pitch black scenes where no action is going on) same deal with VBR mp3s. best to do 2-pass on VBR divx/xvid giving you better Q

[LanEvo7]

Thx

[LanEvo7]

I tried your resolution of 640x272, but the picture looks weird. The video file i have is captured at 640x480 off a vcr, the image is 4:3.

[DaveQB]

try capturing the files in a lossless format,
then the info you have to work with is more inclusive and will result in a better picture,

for eg
i captured 3 hours of football in MJPEG 15
it was 10 gigs,
edited out the ads and so forth,
it was 2:10
added filters etc and compressed it down to one 800mb CD, still looks good.

[LanEvo7]

Can you tell me the EXACT settings you used?

[EddyH]

For viewing fullscreen 4:3 material on a pc, well, it's best to store it at a resolution where height is 3/4 the width .. either you can go for the high quality route, and keep it at your original size of 640x480, or if deinterlacing works ok for you / isn't needed, then 512x384, 480x360 and 400x300 are popular resolutions that give a happy inbetween quality between the near-dvd of 640x480 and the base vcd sizes of 320x240/352x240 etc. Most things I've downloaded off the internet are at these sizes and they look perfectly fine on the screen, especially if you match them to doubled resolutions - ie 800x600, 960x720, 1024x768 (honestly, who uses 640x480 for their desktop any more?! even with TV output?)

As you're capturing from a VCR, the highest resolution may be a bit 'overkill' - even SVHS gets perhaps 400 and some change pixels across the screen on a good day, limiting your file to 400x300 will still look as sharp as the original and cut down on a lot of vhs fuzz.
(not sure on how many lines, but interlacing -may- be less of a prob from tape from some things ive heard, so that could preclude a lower vertical rez too).

(a halfway solution if interlacing is causing headaches is e.g. 320x480, if you can find a way of making it resize properly... rule of thumb, reduce the horizontal clarity before the vertical, tv pictures work to different rules than text on a computer screen )

Whatever you do, don't decimate the frame rate, not less than 24fps anyway. It'll look horrendous and cause headaches later. Even if you're capturing a low-rate animation, it'll interfere with the apparent motion and won't really save much space with DivX or even a decent MPG encoder.

As for bitrates... 2x45 minutes... say 2x46 to give a slight safety margin.

For CDROM, I'd suggest an average of about 980kbps (or 960 with a 'big K') for 74 min discs and 1064k (1040K) for 80s... you then also have a nice overburn area to play with as well, and with variable bitrate divx the quality should be sterling. ((those figures include the audio bitrate however - so with a standard 128k cbr mp3 sound track, it drops to ~840 and ~920))
If it's VCDs you're after, you get a little extra headroom, about 12-15%... so that's ~1112k and ~1200k respectively for total bitrate. With 224k HQ audio, say 880k and 975k for the video; with 160k joint stereo, 945k and 1040k again.

Have fun...