avcodec options: add enum option for color_range

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

libavcodec/options_table.h

@@ -402,7 +402,10 @@ static const AVOption avcodec_options[] = {
 {"ycocg",       "YCOCG",       0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_SPC_YCOCG },       INT_MIN, INT_MAX, V|E|D, "colorspace_type"},
 {"bt2020_ncl",  "BT.2020 NCL", 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_SPC_BT2020_NCL },  INT_MIN, INT_MAX, V|E|D, "colorspace_type"},
 {"bt2020_cl",   "BT.2020 CL",  0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_SPC_BT2020_CL },   INT_MIN, INT_MAX, V|E|D, "colorspace_type"},
-{"color_range", NULL, OFFSET(color_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, AVCOL_RANGE_NB-1, V|E|D},
+{"color_range", "color range", OFFSET(color_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, AVCOL_RANGE_NB-1, V|E|D, "color_range_type"},
+{"unspecified", "Unspecified", 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, INT_MIN, INT_MAX, V|E|D, "color_range_type"},
+{"mpeg", "MPEG (219*2^(n-8))", 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG },        INT_MIN, INT_MAX, V|E|D, "color_range_type"},
+{"jpeg", "JPEG (2^n-1)",       0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG },        INT_MIN, INT_MAX, V|E|D, "color_range_type"},
 {"chroma_sample_location", NULL, OFFSET(chroma_sample_location), AV_OPT_TYPE_INT, {.i64 = AVCHROMA_LOC_UNSPECIFIED }, 0, AVCHROMA_LOC_NB-1, V|E|D},
 {"log_level_offset", "set the log level offset", OFFSET(log_level_offset), AV_OPT_TYPE_INT, {.i64 = 0 }, INT_MIN, INT_MAX },
 {"slices", "number of slices, used in parallelized encoding", OFFSET(slices), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, V|E},