MeGUI itself is lowering bitrate??

[Bh4i]

This is log from some of my MeGUI encoding. I wanted to encode something to Xvid from a original DVD9.

Log for job job25-2

xvid_encraw - raw mpeg4 bitstream encoder written by Christoph Lampert 2002-2003

Trying to retrieve width and height from input header
Input colorspace is YV12
xvidcore build version: xvid-1.2.0-dev
Bitstream version: 1.2.-127
Detected CPU flags: ASM MMX MMXEXT SSE SSE2 TSC
Detected 2 cpus, using 2 threads.

Tot: enctime(ms) =75822.00, length(bytes) = 14614107
Avg: enctime(ms) = 26.31, fps = 38.01, length(bytes) = 5070
I frames: 19 frames, size = 31572/ 599871, quants = 3 / 3.00 / 3
P frames: 1023 frames, size = 9571/9792074, quants = 3 / 3.00 / 3
B frames: 1838 frames, size = 2297/4222162, quants = 4 / 4.00 / 4
desired video bitrate of this job: 1600 kbit/s - obtained video bitrate (approximate): 978 kbit/s

As u can see i told MeGUI to give me a bitrate of 1600 kbps, but why did it only give 978 kbps??

PS: This is not first time its happening to me..

[ChronoCross]

that's not megui....that's the codec. it means your clip isn't taking up that much space.

You should read the sticky in the xvid forum on "how to prevent undersizing"

This is NOT an MeGUI issue.

[Bh4i]

And this:

xvid_encraw - raw mpeg4 bitstream encoder written by Christoph Lampert 2002-2003

Trying to retrieve width and height from input header
Input colorspace is YV12
xvidcore build version: xvid-1.2.0-dev
Bitstream version: 1.2.-127
Detected CPU flags: ASM MMX MMXEXT SSE SSE2 TSC
Detected 2 cpus, using 2 threads.

Tot: enctime(ms) =151767.00, length(bytes) = 41980429
Avg: enctime(ms) = 45.93, fps = 21.77, length(bytes) = 12705
I frames: 44 frames, size = 38168/1679433, quants = 3 / 3.70 / 4
P frames: 1898 frames, size = 17155/32561725, quants = 5 / 5.00 / 5
B frames: 1360 frames, size = 5690/7739271, quants = 6 / 7.97 / 8
desired video bitrate of this job: 1600 kbit/s - obtained video bitrate (approximate): 2443 kbit/s

Now this is oversizing :) I have done many encodes, and everytime i got a bitrate which was almost like the one i choose. But since yesterday, EVERY encode has a significant higher or lower bitrate...

[check]

post your xvid settings :)

[Bh4i]

These are settings i always used. :)

Using profile: Xvid 45% HQ with eqm_v3hr.xcm

ONLY change to settings i made is selecting two threads (and changing bitrate, but i changed that in Bitrate Calculator)

Is this useful info?

encoder commandline:
-i "C:\02.avs" -pass1 "C:\02.stats" -bitrate 1600 -kboost 100 -chigh 20 -clow 7 -overhead 0 -nopacked -vhqmode 4 -qpel -qmatrix "C:\Program Files\MeGUI\extra\eqm_v3hr.xcm" -closed_gop -imin 3 -imax 4 -pmin 3 -pmax 5 -bvhq -bquant_ratio 162 -bquant_offset 0 -bmin 3 -bmax 5 -threads 2

encoder commandline:
-i "C:\02.avs" -pass2 "C:\02.stats" -bitrate 1600 -kboost 100 -chigh 20 -clow 7 -overhead 0 -nopacked -vhqmode 4 -qpel -qmatrix "C:\Program Files\MeGUI\extra\eqm_v3hr.xcm" -closed_gop -imin 3 -imax 4 -pmin 3 -pmax 5 -bvhq -bquant_ratio 162 -bquant_offset 0 -bmin 3 -bmax 5 -threads 2 -avi "C:\02.avi"

[Doom9]

Well, once again you can see that megui is not to be blamed.. it asks for a 1600kbit bitrate. And then, a 151 second source and you're doing twopass? What's that about?

[Bh4i]

Those are music video's. Some of them are 2 mins, some are ~10 mins.

But i never red that using 2 pass will only give better quality from a praticular runtime.

Can u explain from which runtime its useful to do 2 pass or give any link about this please :o

[Doom9]

Two pass only makes sense if you're going for a specified size.. your bitrate makes me think you're not doing that anyway.

[Bh4i]

Ur right, i only wanted ~1600 kbps.

Really man, i didnt knew this :o I thought it was only for better results :o

[foxyshadis]

You should read the xvid presets thread (http://forum.doom9.org/showthread.php?t=107897) to find out how to apply megui's xvid presets. You can't just pick one, pick a bitrate, and go, they simply aren't designed to work that way. Sometime, generic presets that work like x264 presets might get added, if sharktooth feels they're needed.