Author Topic: Loading a UltraHD test clip, Avidemux desaturates the video and contrast  (Read 204 times)

flexy123

  • Newbie
  • *
  • Posts: 1
I loaded a test clip from

https://kodi.wiki/view/Samples

Specificially, Nr. 16 under 4K UHD, this file:

https://mega.nz/#!hJdFEIBI!uSOjZtkkjIVYSfqD9aSfONf1yq__uQvlsf47pCtFvdQ

(The World in HDR)

When I play this file in various media players (MPC-HC, MPC-BE w/ LAV codec, VideoLan), this clip is very color-saturated and has a high contrast.

When I load the clip with Avidemux, the clip is dull, far less saturated and far less contrast. I also played around with output dynamic range settings (eg full, limited etc.). No dice. No matter what I do, the colourful clip looks entirely different in Avidemux, and then also when I save it.

(From what I remember, I also tried to load the test clip in VirtualDUB. There, the clip is also very de-saturated and dull, but VirtualDub crashed at some point. So whatever is changing the clip, it must not be related to Avidemux *per se*.)

Edit: If you load the clip in Avidemux, it is not simply desaturated. The colours are just very off. Watch the original clip, and then load in Avidemux and preview it!
« Last Edit: September 09, 2019, 10:21:38 PM by flexy123 »

eumagga0x2a

  • Moderator
  • Hero Member
  • *****
  • Posts: 3400
Re: Loading a UltraHD test clip, Avidemux desaturates the video and contrast
« Reply #1 on: September 10, 2019, 12:01:58 PM »
Must be related to 10 bits color depth. Avidemux uses 8 bits YV12 (yuv420p with swapped U and V) internally. Avidemux, ffplay and mpv all show identical pale brownish tint when playing this sample on my system, only VLC applies necessary corrections.