Blocky Video

[Jagarus]

I tried encoding a 22:57 episode with virtualdub mod and xvid. FFDSHOW post processing settings are set. The video came out to 41.7mb after doing 2 passes with 992kb/s bitrate, 64kb/s audio and 448x336 video. The video ended up to the same quality as this picture:

http://forum.digital-digest.com/attachment.php?s=&postid=121203

The video source is from a tv tuner, and is in mpeg2 format. I opened it up in DVD2AVI, saved it as a .d2v project and opened it up in gknot. I then saved an .avs file, and opened it up in vdub along with the audio so that I can cut out the commercials. I have been doing this for months, ending up with great quality, but suddenly it goes wrong. When I use the divx5.xx codecs, it works fine. Only with xvid I am getting the blocky video.

[Joe Fenton]

Sounds like you accidentally whacked one of your xvid settings. Please post them.

[ProfDrMorph]

He entered the wrong value for the size of the second pass.

First thing: use internal curve compression for the second pass. I don't think you've got Gordian Knot or anything installed which would allow you to do it externally ( which is useless anyway; XviD's internal algorithms are good ).
Second thing: XviD want's the total size of the video stream ( incl. AVI headers ) and not the bitrate! If your file should have a bitrate of 992 kbit/sec then use this formula to calculate the value you have to enter in XviD's settings:

video stream size = ((total_bitrate - audio_bitrate)/8)*time

(NOTE: this formula does neglect the AVI headers. The difference is so small that in many cases it doesn't matter anyway)

In your case:

x = ((992 - 64)/8)*1377
x = (928/8)*1377
x = 116*1377
x = 137700 + 13770 + 6*1377
x = 151470 + 8262
x = 159732

maybe I should've used at least Windows' calculator but I'm bored anyway atm. :D I hope I did everything correctly. ;)

[Jagarus]

Never mind. I fucked up.:D For some reason, I began entering the bitrate instead of file size in the second pass settings.:sly:

[ProfDrMorph]

that's what I meant ;)