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• fate : add a test for HDR Vivid metadata in HEVC

  3 mars 2022, par Limin Wang

  fate : add a test for HDR Vivid metadata in HEVC
  Signed-off-by : Limin Wang <lance.lmwang@gmail.com>
  

  • [DH] tests/fate/hevc.mak
  • [DH] tests/ref/fate/hevc-hdr-vivid-metadata

• Ghost image issues with ffmpeg -filter_complex displace

  5 juillet 2022, par raul.vila

  I've (almost) been able to apply a displacement based on 2 animated gaussian noise videos, but I'm having issues with a ghost image. A picture is worth a thousand words.

  


  Here you have a script to replicate the issue :

  


  ffmpeg -y -t 2 -f lavfi -i color=c=blue:s=160x120 -c:v libx264 -tune stillimage -pix_fmt rgb24 00_empty.mp4
ffmpeg -y -i 00_empty.mp4 -vf "drawtext=text=string1:y=h/2:x=w-t*w/2:fontcolor=white:fontsize=60" 01_text.mp4
ffmpeg -y -t 2 -f lavfi -i color=c=gray:s=160x120 -c:v libx264 -tune stillimage -pix_fmt rgb24 02_gray.mp4
ffmpeg -y -i 01_text.mp4 -i 02_gray.mp4 -i 02_gray.mp4 -filter_complex "[0][1][2]displace=edge=mirror" 03_displaced_text.mp4


  


  It creates a test video with a scrolling text and a gray dummy video. Then it applies a displacement based on the gray video. If I understand correctly, because the gray video is 100% gray, it should leave the video unchanged (or maybe displace everything by a fixed ammount of pixels), but it creates a "shadow". I tried with 3 different pixel formats (yuv420p, yuv444p, rgb24) because I found this question on stackoverflow talking about that :

  


  

  • Why are Cb and Cr planes displaced differently from lum by the displace complex filter in ffmpeg ?

  


  


  ffmpeg version 5.0.1-full_build-www.gyan.dev

  


  Any idea will be welcome.
  
Thanks !

  


• avfilter/vf_showinfo : fix HDR vivid info

  17 mars 2023, par Zhao Zhili

  avfilter/vf_showinfo : fix HDR vivid info
  Signed-off-by : Zhao Zhili <zhilizhao@tencent.com>
  

  • [DH] libavfilter/vf_showinfo.c