HC enc: Your settings ?

[themaster1]

I'm wondering what settings you guys haved tried with Hcenc

Currently i use the following:

1pass vbr
Best / dc 10 bits
bitrate: 9000-9500 (avg)
Autogop / interlaced TFF(or auto)
AQ=2
Lum=1
dead zone auto
Matrix: avamat6 (retain much grain according to my tests with minimal blocking)

These settings seems great for music videos but not ok for every kind of footage particularly the matrix.

[davexnet]

I think when you specify Lum, it uses a custom matrix.
AQ=1 is a good place to start. If you're having trouble with some material, try 2-pass.

[themaster1]

The default AQ is 2 there must be a reason for that
Correction though after further test the mpeg matrix seems best (for outdoor scene at least with plenty of light)

[davexnet]

I once encoded a couple of documentaries I captured from A&E TV. The quality wasn't that good to begin with,
and I ended up encoding at 1/2 D1 due to bitrate constraints. AQ=2 looked better in that case,
distributed the bits more towards the flat parts and gave the whole thing a better look.

It all depends on the material.

AVStoDVD, the all-in-one DVD encode/author package, uses AQ=1 and LUM=1 for it's HCenc defaults.

[themaster1]

Little comparison (for what it's worth):

1pass vbr, AQ=2, lum gain=1, avamat6 matrix
http://imageshack.us/photo/my-images/88/1passvbraq2lumg1avamat6.jpg/

2pass vbr AQ=3, lumg =0, mpeg matrix
http://imageshack.us/photo/my-images/41/2passaq3lum0mpegmatrix.jpg/

Original (lagarith, YV12)
http://imageshack.us/photo/my-images/225/originalvd.jpg/

This is an outdoor scene with a rapid scene change (noise introduction (snow-like noise) onto the frame made in studio obviously).You can see artefacts in the 1pass vbr wheareas the 2pass is more "high fidelity"

I must say that the 1pass vbr AQ=2, lumg=1 avamat6 matrix work better for low light/dark scenes, it retain much fine grain, verified with the histogram in luma mode.See link below:

http://img696.imageshack.us/img696/1122/14918350.jpg

[davexnet]

Good post. I'll encode some short clips myself, see what I can see.

Any reason for picking avamat6? There's loads included, but I've got no idea when/why you would
pick one over the other.

[themaster1]

It's all about bitrate according to the info i have gathered see below:

bitrate = matrix

+4000k = FOX1
-4000k = FOX2 ou MPEG_STD
-3500k = CCE
-3000k = AVAMAT6, QLB or other
-2000k = AVAMAT7

Sources:
1) http://forum.doom9.org/archive/index.php/t-133470.html
2) http://forum.digital-digest.com/archive/index.php/t-79160.html
3) http://forum.doom9.org/showthread.php?s=&threadid=89897

It's my understanding that these matrix have been made with good compressibility in mind (compressibility 1st, high fidelity 2nd) so personally i take it the other way round as i use 9000k bitrate most of the time, avamat 6 becomes ideal imo (i discard the extreme avamat7)

Ideally you want 8 (on all rows) for Intra and 16 for non-intra frames but the result is not good and the compressibility is close to zero.The higher the number, the more you lose data.