[FFmpeg-devel] [PATCH] avfilter/vf_scale: allow overriding in/out yuv colorspace type

[Michael Niedermayer]

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>
---
 doc/filters.texi       |   15 +++++++++++++++
 libavfilter/vf_scale.c |   44 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)

diff --git a/doc/filters.texi b/doc/filters.texi
index 92f8612..5f6e11b 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -6201,6 +6201,21 @@ applies a bilinear scaling algorithm.
 @item size, s
 Set the video size, the value must be a valid abbreviation or in the
 form @var{width}x at var{height}.
+
+ at item inyuvtype
+ at item outyuvtype
+In/Output YCbCr colorspace type
+ at table @option
+ at item jpeg
+Full 0-255 jpeg style
+
+ at item 709
+ITU Rec BT709
+
+ at item 601
+ITU Rec BT601
+ at end table
+
 @end table
 
 The values of the @var{w} and @var{h} options are expressions
diff --git a/libavfilter/vf_scale.c b/libavfilter/vf_scale.c
index b1246fe..481eb85 100644
--- a/libavfilter/vf_scale.c
+++ b/libavfilter/vf_scale.c
@@ -90,6 +90,9 @@ typedef struct {
     char *w_expr;               ///< width  expression string
     char *h_expr;               ///< height expression string
     char *flags_str;
+
+    char *inyuvtype;
+    char *outyuvtype;
 } ScaleContext;
 
 static av_cold int init(AVFilterContext *ctx)
@@ -182,6 +185,21 @@ static int query_formats(AVFilterContext *ctx)
     return 0;
 }
 
+static const int *parse_yuv_type(const char *s, int *full)
+{
+    const static int32_t yuv2rgb_coeffs[2][4] = {
+        { 117504, 138453, 13954, 34903 }, /* ITU-R Rec. 709 (1990) */
+        { 104597, 132201, 25675, 53279 }, /* ITU-R Rec. 624-4 System B, G */
+    };
+
+    if (s && (strstr(s, "full") || strstr(s, "jpeg")))
+        *full = 1;
+    if (s && strstr(s, "709")) {
+        return yuv2rgb_coeffs[0];
+    } /*else if (s && strstr(s, "601"))*/
+        return yuv2rgb_coeffs[1];
+}
+
 static int config_props(AVFilterLink *outlink)
 {
     AVFilterContext *ctx = outlink->src;
@@ -279,6 +297,30 @@ static int config_props(AVFilterLink *outlink)
                                         scale->flags, NULL, NULL, NULL);
         if (!scale->sws || !scale->isws[0] || !scale->isws[1])
             return AVERROR(EINVAL);
+
+        if (scale->inyuvtype || scale->outyuvtype) {
+            int in_full, out_full, brightness, contrast, saturation;
+            const int *inv_table, *table;
+
+            sws_getColorspaceDetails(scale->sws, (int **)&inv_table, &in_full,
+                                     (int **)&table, &out_full,
+                                     &brightness, &contrast, &saturation);
+
+            if (scale->inyuvtype)
+                inv_table = parse_yuv_type(scale->inyuvtype, &in_full);
+            if (scale->outyuvtype)
+                table     = parse_yuv_type(scale->outyuvtype, &out_full);
+
+            sws_setColorspaceDetails(scale->sws, inv_table, in_full,
+                                     table, out_full,
+                                     brightness, contrast, saturation);
+            sws_setColorspaceDetails(scale->isws[0], inv_table, in_full,
+                                     table, out_full,
+                                     brightness, contrast, saturation);
+            sws_setColorspaceDetails(scale->isws[1], inv_table, in_full,
+                                     table, out_full,
+                                     brightness, contrast, saturation);
+        }
     }
 
     if (inlink->sample_aspect_ratio.num){
@@ -398,6 +440,8 @@ static const AVOption scale_options[] = {
     { "interl", "set interlacing", OFFSET(interlaced), AV_OPT_TYPE_INT, {.i64 = 0 }, -1, 1, FLAGS },
     { "size",   "set video size",          OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
     { "s",      "set video size",          OFFSET(size_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, FLAGS },
+    {  "inyuvtype", "Input YCbCr type",     OFFSET(inyuvtype),  AV_OPT_TYPE_STRING, { .str = NULL }, .flags = FLAGS },
+    { "outyuvtype", "Output YCbCr type",    OFFSET(outyuvtype), AV_OPT_TYPE_STRING, { .str = NULL }, .flags = FLAGS },
     { NULL },
 };
 
-- 
1.7.9.5