[FFmpeg-devel] [PATCH] lavc: clarify color_range semantics

[Stefano Sabatini]

Mark this option as encode-only and extend description.

Address issue: http://trac.ffmpeg.org/ticket/443
---
 libavcodec/avcodec.h       |  6 +++++-
 libavcodec/options_table.h | 14 +++++++-------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 0ac581d660..53ae40255f 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -976,7 +976,11 @@ typedef struct AVCodecContext {
 
     /**
      * MPEG vs JPEG YUV range.
-     * - encoding: Set by user
+     *
+     * - encoding: Set by user to override the default output color range value,
+     *   it might cause a failure in case the specified value is not legal. If
+     *   not specified, libavcodec sets the color range depending on the output
+     *   format.
      * - decoding: Set by libavcodec
      */
     enum AVColorRange color_range;
diff --git a/libavcodec/options_table.h b/libavcodec/options_table.h
index 7924ca6144..a668d39d79 100644
--- a/libavcodec/options_table.h
+++ b/libavcodec/options_table.h
@@ -338,13 +338,13 @@ static const AVOption avcodec_options[] = {
 {"ycocg",             "YCGCO",              0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_SPC_YCGCO },              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", "color range", OFFSET(color_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, INT_MAX, V|E|D, "color_range_type"},
-{"unknown", "Unspecified",     0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, INT_MIN, INT_MAX, V|E|D, "color_range_type"},
-{"tv", "MPEG (219*2^(n-8))",   0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG },        INT_MIN, INT_MAX, V|E|D, "color_range_type"},
-{"pc", "JPEG (2^n-1)",         0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG },        INT_MIN, INT_MAX, 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"},
+{"color_range", "color range", OFFSET(color_range), AV_OPT_TYPE_INT, {.i64 = AVCOL_RANGE_UNSPECIFIED }, 0, INT_MAX, V|E, "color_range_type"},
+{"unknown", "Unspecified",     0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, INT_MIN, INT_MAX, V|E, "color_range_type"},
+{"tv", "MPEG (219*2^(n-8))",   0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG },        INT_MIN, INT_MAX, V|E, "color_range_type"},
+{"pc", "JPEG (2^n-1)",         0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG },        INT_MIN, INT_MAX, V|E, "color_range_type"},
+{"unspecified", "Unspecified", 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_UNSPECIFIED }, INT_MIN, INT_MAX, V|E, "color_range_type"},
+{"mpeg", "MPEG (219*2^(n-8))", 0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_MPEG },        INT_MIN, INT_MAX, V|E, "color_range_type"},
+{"jpeg", "JPEG (2^n-1)",       0, AV_OPT_TYPE_CONST, {.i64 = AVCOL_RANGE_JPEG },        INT_MIN, INT_MAX, V|E, "color_range_type"},
 {"chroma_sample_location", "chroma sample location", OFFSET(chroma_sample_location), AV_OPT_TYPE_INT, {.i64 = AVCHROMA_LOC_UNSPECIFIED }, 0, INT_MAX, V|E|D, "chroma_sample_location_type"},
 {"unknown",     "Unspecified", 0, AV_OPT_TYPE_CONST, {.i64 = AVCHROMA_LOC_UNSPECIFIED }, INT_MIN, INT_MAX, V|E|D, "chroma_sample_location_type"},
 {"left",        "Left",        0, AV_OPT_TYPE_CONST, {.i64 = AVCHROMA_LOC_LEFT },        INT_MIN, INT_MAX, V|E|D, "chroma_sample_location_type"},
-- 
2.25.1