vf_colorspace: Allow overriding input color properties

The filter needs input frames with color properties filled out by
the decoder. Since this is not always possible, add input options to
the filter so that user may override color space, color primaries,
transfer characteristics, and color range, as well as a generic option
to set all properties at once.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

doc/filters.texi

@@ -5235,6 +5235,7 @@ Convert colorspace, transfer characteristics or color primaries.
 The filter accepts the following options:
 
 @table @option
+@anchor{all}
 @item all
 Specify all color properties at once.
 
@@ -5266,6 +5267,7 @@ BT.2020
 
 @end table
 
+@anchor{space}
 @item space
 Specify output colorspace.
 
@@ -5291,6 +5293,7 @@ BT.2020 with non-constant luminance
 
 @end table
 
+@anchor{trc}
 @item trc
 Specify output transfer characteristics.
 
@@ -5319,6 +5322,7 @@ BT.2020 for 12-bits content
 
 @end table
 
+@anchor{primaries}
 @item primaries
 Specify output color primaries.
 
@@ -5344,6 +5348,7 @@ BT.2020
 
 @end table
 
+@anchor{range}
 @item range
 Specify output color range.
 
@@ -5423,6 +5428,21 @@ von Kries whitepoint adaptation
 identity whitepoint adaptation (i.e. no whitepoint adaptation)
 @end table
 
+@item iall
+Override all input properties at once. Same accepted values as @ref{all}.
+
+@item ispace
+Override input colorspace. Same accepted values as @ref{space}.
+
+@item iprimaries
+Override input color primaries. Same accepted values as @ref{primaries}.
+
+@item itrc
+Override input transfer characteristics. Same accepted values as @ref{trc}.
+
+@item irange
+Override input color range. Same accepted values as @ref{range}.
+
 @end table
 
 The filter converts the transfer characteristics, color space and color

libavfilter/vf_colorspace.c

@@ -128,11 +128,11 @@ typedef struct ColorSpaceContext {
 
     ColorSpaceDSPContext dsp;
 
-    enum Colorspace user_all;
-    enum AVColorSpace in_csp, out_csp, user_csp;
-    enum AVColorRange in_rng, out_rng, user_rng;
-    enum AVColorTransferCharacteristic in_trc, out_trc, user_trc;
-    enum AVColorPrimaries in_prm, out_prm, user_prm;
+    enum Colorspace user_all, user_iall;
+    enum AVColorSpace in_csp, out_csp, user_csp, user_icsp;
+    enum AVColorRange in_rng, out_rng, user_rng, user_irng;
+    enum AVColorTransferCharacteristic in_trc, out_trc, user_trc, user_itrc;
+    enum AVColorPrimaries in_prm, out_prm, user_prm, user_iprm;
     enum AVPixelFormat in_format, user_format;
     int fast_mode;
     enum DitherMode dither;
@@ -581,6 +581,10 @@ static int create_filtergraph(AVFilterContext *ctx,
 
     if (!s->out_primaries || !s->in_primaries) {
         s->in_prm = in->color_primaries;
+        if (s->user_iall != CS_UNSPECIFIED)
+            s->in_prm = default_prm[FFMIN(s->user_iall, CS_NB)];
+        if (s->user_iprm != AVCOL_PRI_UNSPECIFIED)
+            s->in_prm = s->user_iprm;
         s->in_primaries = get_color_primaries(s->in_prm);
         if (!s->in_primaries) {
             av_log(ctx, AV_LOG_ERROR,
@@ -638,6 +642,10 @@ static int create_filtergraph(AVFilterContext *ctx,
     if (!s->in_txchr) {
         av_freep(&s->lin_lut);
         s->in_trc = in->color_trc;
+        if (s->user_iall != CS_UNSPECIFIED)
+            s->in_trc = default_trc[FFMIN(s->user_iall, CS_NB)];
+        if (s->user_itrc != AVCOL_TRC_UNSPECIFIED)
+            s->in_trc = s->user_itrc;
         s->in_txchr = get_transfer_characteristics(s->in_trc);
         if (!s->in_txchr) {
             av_log(ctx, AV_LOG_ERROR,
@@ -680,7 +688,13 @@ static int create_filtergraph(AVFilterContext *ctx,
 
     if (!s->in_lumacoef) {
         s->in_csp = in->colorspace;
+        if (s->user_iall != CS_UNSPECIFIED)
+            s->in_csp = default_csp[FFMIN(s->user_iall, CS_NB)];
+        if (s->user_icsp != AVCOL_SPC_UNSPECIFIED)
+            s->in_csp = s->user_icsp;
         s->in_rng = in->color_range;
+        if (s->user_irng != AVCOL_RANGE_UNSPECIFIED)
+            s->in_rng = s->user_irng;
         s->in_lumacoef = get_luma_coefficients(s->in_csp);
         if (!s->in_lumacoef) {
             av_log(ctx, AV_LOG_ERROR,
@@ -1078,6 +1092,22 @@ static const AVOption colorspace_options[] = {
     ENUM("vonkries", WP_ADAPT_VON_KRIES, "wpadapt"),
     ENUM("identity", WP_ADAPT_IDENTITY, "wpadapt"),
 
+    { "iall",       "Set all input color properties together",
+      OFFSET(user_iall),   AV_OPT_TYPE_INT, { .i64 = CS_UNSPECIFIED },
+      CS_UNSPECIFIED, CS_NB - 1, FLAGS, "all" },
+    { "ispace",     "Input colorspace",
+      OFFSET(user_icsp),  AV_OPT_TYPE_INT, { .i64 = AVCOL_SPC_UNSPECIFIED },
+      AVCOL_PRI_RESERVED0, AVCOL_PRI_NB - 1, FLAGS, "csp" },
+    { "irange",     "Input color range",
+      OFFSET(user_irng),  AV_OPT_TYPE_INT, { .i64 = AVCOL_RANGE_UNSPECIFIED },
+      AVCOL_RANGE_UNSPECIFIED, AVCOL_RANGE_NB - 1, FLAGS, "rng" },
+    { "iprimaries", "Input color primaries",
+      OFFSET(user_iprm),  AV_OPT_TYPE_INT, { .i64 = AVCOL_PRI_UNSPECIFIED },
+      AVCOL_PRI_RESERVED0, AVCOL_PRI_NB - 1, FLAGS, "prm" },
+    { "itrc",       "Input transfer characteristics",
+      OFFSET(user_itrc),  AV_OPT_TYPE_INT, { .i64 = AVCOL_TRC_UNSPECIFIED },
+      AVCOL_TRC_RESERVED0, AVCOL_TRC_NB - 1, FLAGS, "trc" },
+
     { NULL }
 };