How to increase the video brightness ?

[pulsarstar]

Hi,
I have a Disney film, in a file format of:
2160p.DDP5.1.Atmos.HDR.HEVC.mkv
In a lot of areas of the movie it is too dark.
You can not see what is happening in the video.
Adjusting my tv to picture "vivid" format does not solve the problem.
So my question is can I use Avidemux to brighten the video up ?
If YES, how would I go about doing it?
Thank You.

[szlldm]

You can do that, but this requires reencoding.
First step, you need to select an encoder at the Video output (default is Copy, where no filtering available).
With that, the Filters button became clickable. Inside the filter manager, choose the Colors category, then either "Contrast" or "MPlayer eq2" filter.

[pulsarstar]

Thank you szlldm for your assistance.
I will try your method out.

[eumagga0x2a]

Are we now able to do a proper HDR (BT.2020 etc.) --> SDR (BT.709) conversion? Else the color will be off, not mentioning the loss of bit depth.

[szlldm]

Are we now able to do a proper HDR (BT.2020 etc.) --> SDR (BT.709) conversion? Else the color will be off, not mentioning the loss of bit depth.

My mistake, i have overlooked that it is HDR. Without the long desired colorspace conversion (tonemapping), still those two color filters are the best shot.

[pulsarstar]

Thank you for the advice.
for a 2160p.DDP5.1.Atmos.HDR.HEVC.mkv film.
should I be choosing HEVC (x265)
from the Video Out drop down menu?

Can I anticipate my follow up question?
Can I view on screen in real time the video playing
to see the changes
to the contrast and brightness of the video.
So I can adjust  to my preference ?

[szlldm]

should I be choosing HEVC (x265)

You could, but it will be very slow. If you can accept a larger size you can select x264, it will be faster.

Can I view on screen in real time the video playing
to see the changes
to the contrast and brightness of the video.

The mentioned filters have previews, so you can immediately see the effect of the settings.

Previously i have overlooked that your source is HDR, if available acquire a non HDR content. With HDR it may be problematic to achieve a desired quality.

[butterw]

@pulsarstar
Avidemux is likely not the best tool for this.

Video encoder GUI's will handle HDR-to-SDR conversion which is likely what you are looking for.

hevc output would be recommended if your pc can handle encoding it, But otherwise x264 with higher bitrate is acceptable.

[pulsarstar]

Thanks Guys.
I much appreciate your thoughts and help on this subject.
Cheers.