x264 Compression brightness/contrast issues

[jagabo]

Download the video I posted and play it. Adjust your graphics card's video proc amp to make it look like the first image in the post I linked to.

https://forum.videohelp.com/threads/339407-x264-Compression-brightness-contrast-issues?...=1#post2110156

[SavageStyle]

Got same as here with graphic card settings:
https://forum.videohelp.com/threads/326496-file-in-Virtualdub-has-strange-colors-when-o...=1#post2022085
With 0-255 i cant see "000" line and With 16-235 i can

but sample1.avi and sample2.avi still not same...
sample2.avi always more brighrer

[jagabo]

Got same as here with graphic card settings:
https://forum.videohelp.com/threads/326496-file-in-Virtualdub-has-strange-colors-when-o...=1#post2022085
With 0-255 i cant see "000" line and With 16-235 i can

I'm not exactly sure what you are saying. All the bars from 000 to 015 should be perfectly black, the same as the background around those bars. All the white bars from 235 to 255 should be the same shade of white as the background around those bars.

[SavageStyle]

Got same as here with graphic card settings:
https://forum.videohelp.com/threads/326496-file-in-Virtualdub-has-strange-colors-when-o...=1#post2022085
With 0-255 i cant see "000" line and With 16-235 i can

I'm not exactly sure what you are saying. All the bars from 000 to 015 should be perfectly black, the same as the background around those bars. All the white bars from 235 to 255 should be the same shade of white as the background around those bars.

Yes. Just as u said.
000-015 - black
235-255 - white
and still sample1.avi and sample2.avi NOT match (wtf)
sample2.avi always more brighrer

[poisondeathray]

You cannot use MPC to take screenshots. Overlay mixer won't work when taking screenshots , only VMR7/9 renderless. So what you see on the monitor will be different than the JPEG screenshot

Use something else to take screenshots. e.g. vdub . options=> preferences=>display => uncheckmark use direct x for display panes

video=> copy input frame , paste into and image editor or even ms paint . Do that for each video

Or are you saying the x264 encode looks like that (different) with 1 instance open ? Do you have fraps enabled in ffdshow? If so, disable it

[jagabo]

Yes. Just as u said.
000-015 - black
235-255 - white
and still sample1.avi and sample2.avi NOT match (wtf)
sample2.avi always more brighrer

The lighter image is the correct image. The problem is that your RGB image is too dark.

Hey, the pictures are gone?

[SavageStyle]

Use something else to take screenshots. e.g. vdub . options=> preferences=>display => uncheckmark use direct x for display panes

video=> copy input frame , paste into and image editor or even ms paint . Do that for each video

They are same in that way.

The lighter image is the correct image. The problem is that your RGB image is too dark.
Hey, the pictures are gone?

The problem is that your RGB image is too dark. (YES, fixed with ffdshow fraps OFF, now color difference left)
Hey, the pictures are gone? (reuploaded withoud brightness difference)

Do you have fraps enabled in ffdshow? If so, disable it

This is 60% of the solution, no brightness difference left, only color:

[poisondeathray]

They are same in that way.

your last screenshot looks like rec601 vs. rec709 difference , so force rec601 conversion matrix for the colors

vdub will use rec601 for the yuv=>rgb conversion so if they look the same to you when you tested vdub, then you should use rec601 (this also prooves video is the same, only you have media player configured differently)

you can enable ffdshow, and under the RGB options choose BT601. You might have to configure it so only RGB is selected (uncheckmark other options like YV12, YUY2 etc...)

there can be a dozen other things going on here too.. it's hard to narrow down because so many things can be different between systems

[jagabo]

Here's what I think is happening: When I open the fraps file directly in VirtualDub fraps (actually ffdshow in my case) is decompressing the video and converting to RGB. That RGB video has blacks at 0, whites at 255 -- perfectly normal. If I open the same video with AviSource() in VirualDub I get YV12, not RGB. And that YV12 video has blacks at y=0 and whites at Y=255. That is very abnormal. If I open that script with VirtualDub the blacks become too black, the whites too bright -- that's because Virtualdub, like most other programs, uses the standard rec.601 matrix to convert the YV12 video for display.

So when ffdshow is decompressing the video and converting to RGB it uses the PC.601 matrix and the colors are normal. But when it decompresses and passes YUV to a program it leaves the levels at the incorrect values, the darks are too dark and the brights are too bright.

Try this in VirtualDub:

1) Start VirtualDub.
2) Select Video -> Color Depth...
3) Set the decompression format to 32 bit RGB.
4) Open Sample.avi.

That video should look normal. You should see lots of detail in the black metalwork at the left of the frame. Then:

1) Start VirtualDub.
2) Select Video -> Color Depth...
3) Set the decompression format to 4:2:0 planar YV12
4) Open Sample.avi.

Now the blacks should be too black. Most of the details in the black metalwork have disappeared.

[poisondeathray]

^yes, that's what I said earlier
https://forum.videohelp.com/threads/339407-x264-Compression-brightness-contrast-issues?...=1#post2110168

Fraps decoder always outputs RGB 0-255 (normal)
Libavcodec (including ffdshow, ffvideosource(), AVISource() IF ffdshow VFW is enabled) will output YV12 full range (abnormal)

[SavageStyle]

1) Do you have fraps enabled in ffdshow? If so, disable it
2) you can enable ffdshow, and under the RGB options choose BT601. You might have to configure it so only RGB is selected (uncheckmark other options like YV12, YUY2 etc...)

This 2 steps is the solution
Thank You jagabo and poisondeathray! You both helped alot. (better that any tech support)
Now both sample1 and sample2 are same with any video player, with 0-255 and 16-235, with any output method. VMR9 or Overlay mixer.
I will add solution to 1st page. If you have any additional information that can be usefull please post.

[poisondeathray]

The reason is ffdshow is doing the RGB conversion now for x264 YV12 material (not the renderer later in the chain) , and you are forcing a matrix (usually it depends on if width >1024 then HD matrix or BT.709 will be used, not Bt.601)

Fraps using fraps decoder always outputs RGB, so RGB is already RGB (there is no RGB conversion )

Most of your other HD videos like movies will not look correct with those settings (colors will be off)

[SavageStyle]

just Turn OFF fraps in ffdshow will be totally enough.
and make sure that graphic card configured to use 0-255 and not 16-235 (use graphic card parameters not Player)

[poisondeathray]

ok

Just be aware that there are many different ways to configure it

And it won't necessarily look the same on other people's systems