[FFmpeg-devel] [PATCH] lavfi/colormatrix: add support for named options

[Stefano Sabatini]

TODO: bump micro
---
 doc/filters.texi             |   33 ++++++++++++++++---
 libavfilter/vf_colormatrix.c |   72 ++++++++++++++++++++++--------------------
 2 files changed, 67 insertions(+), 38 deletions(-)

diff --git a/doc/filters.texi b/doc/filters.texi
index 74a682a..e4aa992 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -2056,12 +2056,37 @@ boxblur=min(h\,w)/10:1:min(cw\,ch)/10:1
 
 @section colormatrix
 
-The colormatrix filter allows conversion between any of the following color
-space: BT.709 (@var{bt709}), BT.601 (@var{bt601}), SMPTE-240M (@var{smpte240m})
-and FCC (@var{fcc}).
+Convert color matrix.
 
-The syntax of the parameters is @var{source}:@var{destination}:
+The filter accepts parameters as a list of @var{key}=@var{value}
+pairs, separated by ":". If the key of the first options is omitted,
+the arguments are interpreted according to the syntax
+ at var{src}:@var{dst}.
+
+A description of the accepted options follows:
+ at table @option
+ at item src
+ at item dst
+Specify the source and destination color matrix. Both values must be
+specified.
+
+The accepted values are:
+ at table @samp
+ at item bt709
+BT.709
+
+ at item bt601
+BT.601
+
+ at item smpte240m
+SMPTE-240M
+
+ at item fcc
+FCC
+ at end table
+ at end table
 
+For example to convert from BT.601 to SMPTE-240M, use the command:
 @example
 colormatrix=bt601:smpte240m
 @end example
diff --git a/libavfilter/vf_colormatrix.c b/libavfilter/vf_colormatrix.c
index 4daa58e..db0125d 100644
--- a/libavfilter/vf_colormatrix.c
+++ b/libavfilter/vf_colormatrix.c
@@ -33,6 +33,7 @@
 #include "formats.h"
 #include "internal.h"
 #include "video.h"
+#include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 #include "libavutil/avstring.h"
 
@@ -54,15 +55,39 @@ static const double yuv_coeff[4][3][3] = {
       { -0.4450, -0.0550, +0.5000 } },
 };
 
+enum ColorMode {
+    COLOR_MODE_NONE = -1,
+    COLOR_MODE_BT709,
+    COLOR_MODE_FCC,
+    COLOR_MODE_BT601,
+    COLOR_MODE_SMPTE240M,
+    COLOR_MODE_COUNT
+};
+
 typedef struct {
+    const AVClass *class;
     int yuv_convert[16][3][3];
     int interlaced;
-    int source, dest, mode;
-    char src[256];
-    char dst[256];
+    enum ColorMode source, dest;
+    int mode;
     int hsub, vsub;
 } ColorMatrixContext;
 
+#define OFFSET(x) offsetof(ColorMatrixContext, x)
+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption colormatrix_options[] = {
+    { "src", "set source color matrix",      OFFSET(source), AV_OPT_TYPE_INT, {.i64=COLOR_MODE_NONE}, COLOR_MODE_NONE, COLOR_MODE_COUNT-1, .flags=FLAGS, .unit="color_mode" },
+    { "dst", "set destination color matrix", OFFSET(dest),   AV_OPT_TYPE_INT, {.i64=COLOR_MODE_NONE}, COLOR_MODE_NONE, COLOR_MODE_COUNT-1, .flags=FLAGS, .unit="color_mode" },
+    { "bt709",     "set BT.709 colorspace",      0, AV_OPT_TYPE_CONST, {.i64=COLOR_MODE_BT709},       .flags=FLAGS, .unit="color_mode" },
+    { "fcc",       "set FCC colorspace   ",      0, AV_OPT_TYPE_CONST, {.i64=COLOR_MODE_FCC},         .flags=FLAGS, .unit="color_mode" },
+    { "bt601",     "set BT.609 colorspace",      0, AV_OPT_TYPE_CONST, {.i64=COLOR_MODE_BT601},       .flags=FLAGS, .unit="color_mode" },
+    { "smpte240m", "set SMPTE-240M colorspace",  0, AV_OPT_TYPE_CONST, {.i64=COLOR_MODE_SMPTE240M},   .flags=FLAGS, .unit="color_mode" },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(colormatrix);
+
 #define ma m[0][0]
 #define mb m[0][1]
 #define mc m[0][2]
@@ -133,40 +158,14 @@ static void calc_coefficients(AVFilterContext *ctx)
     }
 }
 
-static const char *color_modes[] = {"bt709", "FCC", "bt601", "smpte240m"};
-
-static int get_color_mode_index(const char *name)
-{
-    int i;
-
-    for (i = 0; i < FF_ARRAY_ELEMS(color_modes); i++)
-        if (!av_strcasecmp(color_modes[i], name))
-            return i;
-    return -1;
-}
+static const char *color_modes[] = {"bt709", "fcc", "bt601", "smpte240m"};
 
 static av_cold int init(AVFilterContext *ctx, const char *args)
 {
     ColorMatrixContext *color = ctx->priv;
 
-    if (!args)
-        goto usage;
-    if (sscanf(args, "%255[^:]:%255[^:]", color->src, color->dst) != 2) {
-    usage:
-        av_log(ctx, AV_LOG_ERROR, "usage: <src>:<dst>\n");
-        av_log(ctx, AV_LOG_ERROR, "possible options: bt709,bt601,smpte240m,fcc\n");
-        return -1;
-    }
-
-    color->source = get_color_mode_index(color->src);
-    if (color->source < 0) {
-        av_log(ctx, AV_LOG_ERROR, "unknown color space %s\n", color->src);
-        return AVERROR(EINVAL);
-    }
-
-    color->dest = get_color_mode_index(color->dst);
-    if (color->dest < 0) {
-        av_log(ctx, AV_LOG_ERROR, "unknown color space %s\n", color->dst);
+    if (color->source == COLOR_MODE_NONE || color->dest == COLOR_MODE_NONE) {
+        av_log(ctx, AV_LOG_ERROR, "Unspecified source or destination color space\n");
         return AVERROR(EINVAL);
     }
 
@@ -313,7 +312,8 @@ static int config_input(AVFilterLink *inlink)
     color->hsub = pix_desc->log2_chroma_w;
     color->vsub = pix_desc->log2_chroma_h;
 
-    av_log(ctx, AV_LOG_VERBOSE, "%s -> %s\n", color->src, color->dst);
+    av_log(ctx, AV_LOG_VERBOSE, "%s -> %s\n",
+           color_modes[color->source], color_modes[color->dest]);
 
     return 0;
 }
@@ -375,13 +375,17 @@ static const AVFilterPad colormatrix_outputs[] = {
     { NULL }
 };
 
+static const char *colormatrix_shorthand[] = { "src", "dst", NULL };
+
 AVFilter avfilter_vf_colormatrix = {
     .name          = "colormatrix",
-    .description   = NULL_IF_CONFIG_SMALL("Color matrix conversion"),
+    .description   = NULL_IF_CONFIG_SMALL("Convert color matrix."),
 
     .priv_size     = sizeof(ColorMatrixContext),
     .init          = init,
     .query_formats = query_formats,
     .inputs        = colormatrix_inputs,
     .outputs       = colormatrix_outputs,
+    .priv_class    = &colormatrix_class,
+    .shorthand     = colormatrix_shorthand,
 };
-- 
1.7.9.5