doom9's new CCE guide

[sundance]

While reading doom9's updated "Getting the best out of CCE" I noticed that he changed his settings on the luminance level from 0..255 to 16..235.
Does anybody have a reason for this?
Does it yield a better quality despite lowering the video's contrast?

And, regarding the example given in the guide, what's the use of setting/not setting "Upper field first" in CCE (depending on what Bitrateviewer tells you in "Field topfirst") when you have progressive material? ("Pic. structure: Frame")

[auenf]

in CCE its best to set TFF ticked all the time, as unchecking it makes CCE shift the footage up one like instead of just changing the TFF flag.

for progressive, you dont want CCE moving the footage up a line ;)

Enf...

[wmansir]

the luma range question was addressed recently, you can search for it.

but the quick answer is this: US TV sets cannot display pure black (0) or pure white 255, so the range has to be limited to 16-235.

If you are just encoding video for PC use only, you can use the full range.

EDIT:

After re-reading your post, auenf, I think you may have it backwards there. According to this thread (http://forum.doom9.org/showthread.php?s=&threadid=25540&highlight=top+field+first), which includes a link to an article, CHECKING upper field first shifts the video, unchecking it leaves the video alone.

Also, I don't think this setting hurts progressive video, unless you are trying to get your letterbox to line up with Macroblock boundries.

[wmansir]

Just to be sure on this UFF subject I did a quick test and confirmed that checking UFF shifts the video up one line, unchecking it does not.

[sundance]

Thanks a lot for your hints, it helped pretty much to "update" my understanding of CCE. In another post regarding the luminance issue I read something about a histogram function in VirtualDub to determine the lum-range of your source material. As I'm not too familiar with VD, I could find out how get such a luminance histogram. Any hints?

Thanks
-sundance-

[wmansir]

Add the Levels filter and click Sample Video. You then have a couple of choices as to how accurate you want to sample the video.

Also you can open a preview window, select a frame and then click Sample Frame to get the histogram of a single frame.

[sundance]

wmansir,
thanks for the tip, I'll give it a try.

Btw, after searching for other "luminance" threads (yes, I did that before starting this one but accidently searched for "luminace"...) I found an interesting info about DVD2AVI. It says that using PC- or TV-scale you end up with different luminance ranges. To be perfectly honest, I don't understand this. I always thought of DVD2AVI to generate sort of a frame list when saving a project (besides demuxing audio tracks, etc). How can this generate different kind of luminance ranges in the d2v file?
Could anyone please shed some light on DVD2AVI's functionality?

-sundance-

[wmansir]

I also doubt setting D2V to use TV scale will create the proper scale in a .d2v file. The reason is because the setting is found under the Video menu labled YUV->RGB, and as we all know using AviSynth to edit the video, and CCE (or Fast Recompress in Vdub) to encode keeps the video in the YUV color space. So I think this setting is only used when D2V is creating an .avi file, not just .d2v project files.

You can see a difference in the D2V preview window when you change the setting, but a quick test showed no difference when creating an .d2v, then opening the .avs in VDub.

[sundance]

Did a quick test too, as there is a luminance value in the d2v file (which is set to "Luminance=128,0"). When you fiddle with that parameters you'll end up with a different video but TV scale or PC scale don't change this value...

-sundance-

[auenf]

Originally posted by wmansir
After re-reading your post, auenf, I think you may have it backwards there. According to this thread (http://forum.doom9.org/showthread.php?s=&threadid=25540&highlight=top+field+first), which includes a link to an article, CHECKING upper field first shifts the video, unchecking it leaves the video alone.

Also, I don't think this setting hurts progressive video, unless you are trying to get your letterbox to line up with Macroblock boundries.


hmm, il have another play at work, but with lower field first source, i get the wrong field order with either setting, but encoding with TFF ticked, then changing the TFF flag afterwards produces a field right clip.

Enf...