avfilter/vf_zscale: make it possible to override input frame parameters

Mostly useful when there is no such parameters present at all.
Signed-off-by: Paul B Mahol <onemda@gmail.com>

doc/filters.texi

@@ -12784,6 +12784,63 @@ Possible value are:
 @end table
 
 Default is same as input.
+
+@item rangein, rin
+Set the input color range.
+
+Possible values are:
+@table @var
+@item input
+@item limited
+@item full
+@end table
+
+Default is same as input.
+
+@item primariesin, pin
+Set the input color primaries.
+
+Possible values are:
+@table @var
+@item input
+@item 709
+@item unspecified
+@item 170m
+@item 240m
+@item 2020
+@end table
+
+Default is same as input.
+
+@item transferin, tin
+Set the input transfer characteristics.
+
+Possible values are:
+@table @var
+@item input
+@item 709
+@item unspecified
+@item 601
+@item linear
+@item 2020_10
+@item 2020_12
+@end table
+
+Default is same as input.
+
+@item matrixin, min
+Set the input colorspace matrix.
+
+Possible value are:
+@table @var
+@item input
+@item 709
+@item unspecified
+@item 470bg
+@item 170m
+@item 2020_ncl
+@item 2020_cl
+@end table
 @end table
 
 The values of the @option{w} and @option{h} options are expressions

libavfilter/vf_zscale.c

@@ -88,6 +88,10 @@ typedef struct ZScaleContext {
     int trc;
     int primaries;
     int range;
+    int colorspace_in;
+    int trc_in;
+    int primaries_in;
+    int range_in;
     char *size_str;
 
     char *w_expr;               ///< width  expression string
@@ -448,10 +452,10 @@ static int filter_frame(AVFilterLink *link, AVFrame *in)
         s->src_format.depth = desc->comp[0].depth;
         s->src_format.pixel_type = desc->comp[0].depth > 8 ? ZIMG_PIXEL_WORD : ZIMG_PIXEL_BYTE;
         s->src_format.color_family = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_COLOR_RGB : ZIMG_COLOR_YUV;
-        s->src_format.matrix_coefficients = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_MATRIX_RGB : convert_matrix(in->colorspace);
-        s->src_format.transfer_characteristics = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_TRANSFER_UNSPECIFIED : convert_trc(in->color_trc);
-        s->src_format.color_primaries = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_PRIMARIES_UNSPECIFIED : convert_primaries(in->color_primaries);
-        s->src_format.pixel_range = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_RANGE_FULL : convert_range(in->color_range);
+        s->src_format.matrix_coefficients = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_MATRIX_RGB : s->colorspace_in == -1 ? convert_matrix(in->colorspace) : s->colorspace_in;
+        s->src_format.transfer_characteristics = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_TRANSFER_UNSPECIFIED : s->trc_in == - 1 ? convert_trc(in->color_trc) : s->trc_in;
+        s->src_format.color_primaries = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_PRIMARIES_UNSPECIFIED : s->primaries_in == -1 ? convert_primaries(in->color_primaries) : s->primaries_in;
+        s->src_format.pixel_range = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_RANGE_FULL : s->range_in == -1 ? convert_range(in->color_range) : s->range_in;
 
         s->dst_format.width = out->width;
         s->dst_format.height = out->height;
@@ -693,6 +697,14 @@ static const AVOption zscale_options[] = {
     {     "ycgco",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_YCGCO},       0, 0, FLAGS, "matrix" },
     {     "2020_ncl",         0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_2020_NCL},    0, 0, FLAGS, "matrix" },
     {     "2020_cl",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_2020_CL},     0, 0, FLAGS, "matrix" },
+    { "rangein", "set input color range", OFFSET(range_in),     AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_RANGE_FULL, FLAGS, "range" },
+    { "rin",     "set input color range", OFFSET(range_in),     AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_RANGE_FULL, FLAGS, "range" },
+    { "primariesin", "set input color primaries", OFFSET(primaries_in), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_PRIMARIES_2020, FLAGS, "primaries" },
+    { "pin",         "set input color primaries", OFFSET(primaries_in), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_PRIMARIES_2020, FLAGS, "primaries" },
+    { "transferin", "set input transfer characteristic", OFFSET(trc_in), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_TRANSFER_2020_12, FLAGS, "transfer" },
+    { "tin",        "set input transfer characteristic", OFFSET(trc_in), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_TRANSFER_2020_12, FLAGS, "transfer" },
+    { "matrixin", "set input colorspace matrix", OFFSET(colorspace_in), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_MATRIX_2020_CL, FLAGS, "matrix" },
+    { "min",      "set input colorspace matrix", OFFSET(colorspace_in), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_MATRIX_2020_CL, FLAGS, "matrix" },
     { NULL }
 };