vo_opengl: generalize HDR tone mapping to gamut mapping

Since this code was already written for HDR, and is now per-channel
(because it works better for HDR as well), we can actually reuse this to
get very high quality gamut mapping without clipping. The only required
change is to move the tone mapping from before the gamut map to after
the gamut map. Additonally, we need to also account for changes in the
signal range as a result of applying the CMS when we compute ref_peak,
which is fortunately pretty easy because we only need to consider the
case of primaries mapping to themselves.

Since `HDR` no longer really makes sense as a label, rename it to
`--tone-mapping` in general. Also fits better with
`--tone-mapping-desat` etc.

Arguably we could also rename `--hdr-compute-peak`, but that option is
basically only useful for HDR content anyway because we don't need
information about the signal range for gamut mapping.

This (finally!) gives us reasonably high quality gamut mapping even in
the absence of an ICC profile / 3DLUT.

1 files changed, 1 insertions, 1 deletions

diff --git a/video/out/opengl/video.h b/video/out/opengl/video.h
index 5b50cdd3f2..d74f3cf576 100644
--- a/video/out/opengl/video.h
+++ b/video/out/opengl/video.h
@@ -110,7 +110,7 @@ struct gl_video_opts {
     int target_prim;
     int target_trc;
     int target_brightness;
-    int hdr_tone_mapping;
+    int tone_mapping;
     int compute_hdr_peak;
     float tone_mapping_param;
     float tone_mapping_desat;