991018 - Avidemux to show brighter images

[hamidi2]

Hi
I'm not going to convert with Avidemux, just cut is intended. I'm not going to change the brightness of the result cut video and I use Avidemux just to cut some portions of the source movie. The resulting cut videos will be played with VLC which has some video filters to correct gamma for dark movies.
With this introduction, I need to "see" what I'm working on. The scenes are darker than I can manipulate them properly. I need to have similar filters as VLC when:
- watching a portion of the source movie, to see and decide better what parts to cut.
- looking at video images to create stills from better parts.
In glance, I need to correct gamma just to see better what I'm working on.
I searched in options and couldn't find what I'm looking for.
Any idea?
PS. Avidemux 2.7.4 on Ubuntu 20.04

[butterw]

Open video > set codec > you can then add filters
Filters > Colors > ...

You'll need to filter/preview the output, but I'm not sure whether it's going to be very practical...

After cutting, remember to disable the video codec before Saving.

[hello_hello]

I don't know of any other programs that edit, save without re-encoding, and also have a video preview.
I don't think I have the latest version of Avidemux installed, but based on how it works for me, try this:

(Edit: butterw beat me to the filters idea)

Select "Null" for the Video Output. That gives you access to the filters. Click on Filters and under the Color menu, add the Contrast filter. It also has a brightness control, which is the next best thing to gamma.
Under the Transform menu, add the Change FPS filter. Double click to configure it and change the output fps to 1.00 fps.
Close the Filters configuration and from the top menu, select Video/Play Filtered.

It seems the preview will only show the filtering while the video is playing, so by slowing the frame rate to 1 fps, you at least get to examine each frame for a whole second with the brightness increased by the contrast filter while it's playing.
The audio will be completely out of sync, but the duration displayed in the navigation area doesn't change. Best as I can tell, when you edit, the video and audio are still edited together as though the video was playing at the original speed, so the A/V sync won't change for the output.

When you're done, switch Video Output to "Copy" and save.

[butterw]

changing your monitor or video driver settings will likely work better and end up being less trouble.

[hamidi2]

Thanks for your help.
I agree with you @butterw. If like Windows I would have an icon in the tray which appears when I install the graphics card driver and when I click on it, I may change the display settings like gamma or brightness, the problem could be resolved. Especially, it might have different settings for video than display. But it's Ubuntu and I'm using the OS driver and there's no additional software installed. It's the onboard Intel graphics adapter. I'm not sure whether such an equivalent software is available for Linux MATE.
Your solution is a good idea too @hello_hello, but it's not applicable for when I'm not playing the video, which is the most of times. I rarely do this and usually save stills after navigating with up/down arrows. Switching between Copy and null is also an overhead. I couldn't figure out what you meant in your first post @butterw. I think you meant the same way as @hello_hello described.

[butterw]

yes #2==#3.

You should be able to adjust settings on your monitor (changed with the buttons on your monitor).

[hamidi2]

The monitor is a bit old. I spent some time to calibrate it so that texts can be read and videos can be watched nearly properly. Besides, when videos can't be changed separately, it's not applicable, because texts get unreadable because of high contrast.
The best choice would be the customization by the graphics adapter driver which apparently is not available on Linux.