From 0bf8d625ee691d9fe04cf4901f99debd86126477 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20B=C5=93sch?= <u@pkh.me>
Date: Fri, 18 Dec 2015 20:04:07 +0100
Subject: [PATCH] avfilter/scale/WIP: brightness+contrast+saturation

---
 libavfilter/vf_scale.c | 24 ++++++++++++++++++++++--
 1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/libavfilter/vf_scale.c b/libavfilter/vf_scale.c
index f2f475e..bda1bf7 100644
--- a/libavfilter/vf_scale.c
+++ b/libavfilter/vf_scale.c
@@ -110,6 +110,7 @@ typedef struct ScaleContext {
     int in_v_chr_pos;
 
     int force_original_aspect_ratio;
+    double brightness, contrast, saturation;
 } ScaleContext;
 
 AVFilter ff_vf_scale2ref;
@@ -353,7 +354,10 @@ static int config_props(AVFilterLink *outlink)
         inlink0->h == outlink->h &&
         !scale->out_color_matrix &&
         scale->in_range == scale->out_range &&
-        inlink0->format == outlink->format)
+        inlink0->format == outlink->format &&
+        scale->brightness < 0 &&
+        scale->contrast < 0 &&
+        scale->saturation < 0)
         ;
     else {
         struct SwsContext **swscs[3] = {&scale->sws, &scale->isws[0], &scale->isws[1]};
@@ -532,7 +536,10 @@ static int filter_frame(AVFilterLink *link, AVFrame *in)
         || scale->out_color_matrix
         || scale-> in_range != AVCOL_RANGE_UNSPECIFIED
         || in_range != AVCOL_RANGE_UNSPECIFIED
-        || scale->out_range != AVCOL_RANGE_UNSPECIFIED) {
+        || scale->out_range != AVCOL_RANGE_UNSPECIFIED
+        || scale->brightness >= 0
+        || scale->contrast >= 0
+        || scale->saturation >= 0) {
         int in_full, out_full, brightness, contrast, saturation;
         const int *inv_table, *table;
 
@@ -540,6 +547,16 @@ static int filter_frame(AVFilterLink *link, AVFrame *in)
                                  (int **)&table, &out_full,
                                  &brightness, &contrast, &saturation);
 
+        av_log(0,0,"ORIG: brightness:%d contrast:%d saturation:%d\n",
+               brightness, contrast, saturation);
+
+        if (scale->brightness >= 0) brightness = av_clip_uint16(scale->brightness * UINT16_MAX);
+        if (scale->contrast   >= 0) contrast   = av_clip_uint16(scale->contrast   * UINT16_MAX);
+        if (scale->saturation >= 0) saturation = av_clip_uint16(scale->saturation * UINT16_MAX);
+
+        av_log(0,0,"TO: brightness:%d contrast:%d saturation:%d\n",
+               brightness, contrast, saturation);
+
         if (scale->in_color_matrix)
             inv_table = parse_yuv_type(scale->in_color_matrix, av_frame_get_colorspace(in));
         if (scale->out_color_matrix)
@@ -651,6 +668,9 @@ static const AVOption scale_options[] = {
     { "increase", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 2 }, 0, 0, FLAGS, "force_oar" },
     { "param0", "Scaler param 0",             OFFSET(param[0]),  AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT  }, INT_MIN, INT_MAX, FLAGS },
     { "param1", "Scaler param 1",             OFFSET(param[1]),  AV_OPT_TYPE_DOUBLE, { .dbl = SWS_PARAM_DEFAULT  }, INT_MIN, INT_MAX, FLAGS },
+    { "brightness", "override brightness colorspace", OFFSET(brightness), AV_OPT_TYPE_DOUBLE, { .dbl = -1 }, -1, 1, FLAGS },
+    { "contrast",   "override contrast colorspace",   OFFSET(contrast),   AV_OPT_TYPE_DOUBLE, { .dbl = -1 }, -1, 1, FLAGS },
+    { "saturation", "override saturation colorspace", OFFSET(saturation), AV_OPT_TYPE_DOUBLE, { .dbl = -1 }, -1, 1, FLAGS },
     { NULL }
 };
 
-- 
2.6.4