Really Undersized Video: Horrible Quality

[NuclearFusi0n]

I did 4 encodes of "Donnie Darko," a real life movie with a fair bit of film grain, but not much.
2 encodes with filtered with Convolution3d "MovieHQ"
2 encodes were not filtered
each setting was also done with hvs_best, and MPEG
so i had:

Convolution3d MPEG
Convolution3d HVS_Best
NoConvolution3d MPEG
NoConvolution3d HVS_Best

LoadPlugin("C:\Program Files\AVISynth\MPEG2Dec3.dll")
LoadPlugin("C:\Program Files\AVISynth\Convolution3DYV12.dll")
mpeg2source("C:\Donnie Darko\rawr.d2v", idct=3)
crop(0,50,720,374)
#Convolution3d (preset="movieHQ")
LanczosResize(672,288)
The # was removed for the Convolution3d encodes.

Settings for XviD ()
Mode: 2 Pass - 2nd pass Int.
Dummy 2nd Pass: OFF
Desired Size: 1064099KB
I-frame Boost: 0%
Below I-frame Distance: 10%
I-frame Bitrate Reduction: 20%
Curve Compression: Payback with Bias, Bitrate Payback Delay: 250frames
High Bitrate Scenes: 0%, Low Bitrate Scenes: 0%
Hinted Motion Estimation: OFF
Alternative Curve System: OFF,
Motion Search Precision: 6 - Ultra
Quantization Type: MPEG or HVS_Best (depending on encode)
FourCC Used: XVID
Max I-frame Interval: 300, Min I-frame Interval: 1
Lumimasking: OFF
Interlacing: OFF
Greyscale: OFF
Quarterpel: ON
Global Motion Compensation: OFF
Chroma Motion: ON
Max B-frames: 3
B-frames Quantizer Ratio: 150%
B-frames Quantizer Offset: 100
Packed Bitstream: OFF
DX50 B-VOP Compatibility: ON
Print debug info on each frame: OFF
Min I-frame Quantizer: 2, Max I-frame Quantizer: 31
Min P-frame Quantizer: 2, Max P-frame Quantizer: 31
Max Bitrate: 10000kbps, Max Overflow Improvement: %, Max Overflow Degradation: %
Start Credits: OFF, End Credits: OFF,

Target size is 1,064,099 KB, over a gigabyte.

1st pass Convolution3d MPEG: 715,364 KB
2nd pass Convolution3d MPEG: 706,106 KB

1st pass Convolution3d HVS_Best: 715,350 KB
2nd pass Convolution3d HVS_Best: 705,924 KB

1st pass NoConvolution3d HVS_Best: 784,794 KB
2nd pass NoConvolution3d HVS_Best: 772,326 KB

1st pass NoConvolution3d MPEG: Aborted
2nd pass NoConvolution3d MPEG: Aborted

I will update as things finish up. I used Koepi's 12/09/2002 build, the latest dev build. So far, all of the movies produced look horrible. There is smearing, flickering little specks all over, artifacts, bleh. :(

[Jon Ingram]

Try an encode without using B-frames.

[manono]

Hi-

It came out undersized because you maxed out the file size (as you should be able to tell from the first pass file sizes). Why are you even doing 2 passes? Or do it for 1 CD. That movie compresses very well. I used an earlier build and it came out very nicely, so I can't comment on the smearing and other artifacts.

If you want a larger file size, maybe take the resolution higher, use Lanczos with no C3D, no B-frames.

[MaTTeR]

I think it's already been mentioned that using Qpel with B-Frames is not advised yet. Similar artifact problems with this combo has been discussed.

[Didée]

It could be something completely other!

You used a custom matrix, as you wrote. Did you play around with other custom matrices beforehand?

Some days ago, I experienced something really strange:
A played around with some matrices ... the latest tries were made with matrices for very low bitrates.
I finished with experimenting, and switched back to the built-in standard h263 and mpeg matrices. From that point on, XviD encoder produced nothing else than crap! Whatever I tried, nothing changed.
I did hit the "load default" button. Still, nothing but crap quality. (And also small filesizes.)

I got the impression that the last custom matrix I had used somehow got "locked" in the encoder.

I re-installed XviD, and everything was fine again! (I did not try to re-boot beforehand: re-installing was much faster...)

Try if this helps!

Has anyone else made some strange experience when using custom matrices?

[Gaia]

No, custom matrixes have worked very nicely. No problems at all. No problems with QPel+B-frames either.

[sysKin]

What are you using to decode the movie? If it's ffdshow, and you use postprocessing, don't use 'mplayer' postprocessing method but 'Nic's' one instead.

Mplayer's postprocessing does something very weird with b-frames+qpel...

Radek

[NuclearFusi0n]

Originally posted by sysKin
What are you using to decode the movie? If it's ffdshow, and you use postprocessing, don't use 'mplayer' postprocessing method but 'Nic's' one instead.

Mplayer's postprocessing does something very weird with b-frames+qpel...

Radek
I'm using ffdshow with no post processing.

[Selur]

had a similar problem when I used the FourCC: DX50 and decoded with ffdshow, for me the problem was fixed when I told ffdshow to use Xvid for decoding,..

may be this helps,..

Cu Selur

Ps.: Strange thing is it only seemed to happen when quantizer 5+ and b-frames were used together,..