vo_gpu_next: add --hdr-contrast-recovery/smoothness

New upstream feature. Disabled by default.

DOCS/interface-changes.rst

@@ -87,6 +87,7 @@ Interface changes
       --no-gpu-shader-cache to disable)
     - add `--directory-mode=recursive|lazy|ignore`
     - ctrl+h now uses `auto-safe` rather than `auto` when turing on hardware decoding
+    - add `--hdr-contrast-recovery` and `--hdr-contrast-smoothness`
  --- mpv 0.35.0 ---
     - add the `--vo=gpu-next` video output driver, as well as the options
       `--allow-delayed-peak-detect`, `--builtin-scalers`,

DOCS/man/options.rst

@@ -6713,6 +6713,18 @@ them.
     aggressive, up to the limit of the high threshold (at which point the
     filter becomes instant).
 
+``--hdr-contrast-recovery=<0.0..2.0>``, ``--hdr-contrast-smoothness=<1.0..100.0>``
+    Enables the HDR contrast recovery algorithm, which is to designed to
+    enhance contrast of HDR video after tone mapping. The strength (default:
+    0.0) indicates the degree of contrast recovery, with 0.0 being completely
+    disabled and 1.0 being 100% strength. Values higher than 1.0 are allowed,
+    but may result in excessive sharpening. The smoothness (default: 3.5)
+    indicates the degree to which the HDR source is low-passed in order to
+    obtain contrast information - a value of 2.0 corresponds to 2x downscaling.
+    Users on low DPI displays (<= 100) may want to lower this value, while
+    users on very high DPI displays ("retina") may want to increase it. (Only
+    for ``vo=gpu-next``)
+
 ``--use-embedded-icc-profile``
     Load the embedded ICC profile contained in media files such as PNG images.
     (Default: yes). Note that this option only works when also using a display

video/out/gpu/video.c

@@ -325,6 +325,7 @@ static const struct gl_video_opts gl_video_opts_def = {
         .decay_rate = 100.0,
         .scene_threshold_low = 5.5,
         .scene_threshold_high = 10.0,
+        .contrast_smoothness = 3.5,
     },
     .early_flush = -1,
     .shader_cache = true,
@@ -421,6 +422,10 @@ const struct m_sub_options gl_video_conf = {
             M_RANGE(0, 20.0)},
         {"hdr-scene-threshold-high", OPT_FLOAT(tone_map.scene_threshold_high),
             M_RANGE(0, 20.0)},
+        {"hdr-contrast-recovery", OPT_FLOAT(tone_map.contrast_recovery),
+            M_RANGE(0, 2.0)},
+        {"hdr-contrast-smoothness", OPT_FLOAT(tone_map.contrast_smoothness),
+            M_RANGE(1.0, 100.0)},
         {"opengl-pbo", OPT_BOOL(pbo)},
         SCALER_OPTS("scale",  SCALER_SCALE),
         SCALER_OPTS("dscale", SCALER_DSCALE),

video/out/gpu/video.h

@@ -133,6 +133,8 @@ struct gl_tone_map_opts {
     float decay_rate;
     float scene_threshold_low;
     float scene_threshold_high;
+    float contrast_recovery;
+    float contrast_smoothness;
     int gamut_mode;
     bool visualize;
 };

video/out/vo_gpu_next.c

@@ -1967,6 +1967,11 @@ static void update_render_options(struct vo *vo)
         p->color_map.tone_mapping_param = 0.0;
     p->color_map.visualize_lut = opts->tone_map.visualize;
 
+#if PL_API_VER >= 285
+    p->color_map.contrast_recovery = opts->tone_map.contrast_recovery;
+    p->color_map.contrast_smoothness = opts->tone_map.contrast_smoothness;
+#endif
+
 #if PL_API_VER >= 269
     if (opts->tone_map.gamut_mode != GAMUT_AUTO)
         p->color_map.gamut_mapping = gamut_modes[opts->tone_map.gamut_mode];