Add color source.

Originally committed as revision 24282 to svn://svn.ffmpeg.org/ffmpeg/trunk

doc/filters.texi

@@ -229,6 +229,45 @@ Flip the input video vertically.
 
 Below is a description of the currently available video sources.
 
+@section color
+
+Provide an uniformly colored input.
+
+It accepts the following parameters:
+@var{color}:@var{frame_size}:@var{frame_width}
+
+Follows the description of the accepted parameters.
+
+@table @option
+
+@item color
+Specify the color of the source. It can be the name of a color (case
+insensitive match) or a 0xRRGGBB[AA] sequence, possibly followed by an
+alpha specifier. The default value is "black".
+
+@item frame_size
+Specify the size of the sourced video, it may be a string of the form
+@var{width}x@var{heigth}, or the name of a size abbreviation. The
+default value is "320x240".
+
+@item frame_rate
+Specify the frame rate of the sourced video, as the number of frames
+generated per second. It has to be a string in the format
+@var{frame_rate_num}/@var{frame_rate_den}, an integer number, a float
+number or a valid video frame rate abbreviation. The default value is
+"25".
+
+@end table
+
+For example the following graph description will generate a red source
+with an opacity of 0.2, with size "qcif" and a frame rate of 10
+frames per second, which will be overlayed over the source connected
+to the pad with identifier "in".
+
+@example
+"color=red@@0.2:qcif:10 [color]; [in][color] overlay [out]"
+@end example
+
 @section nullsrc
 
 Null video source, never return images. It is mainly useful as a

libavfilter/Makefile

@@ -28,6 +28,7 @@ OBJS-$(CONFIG_UNSHARP_FILTER)                += vf_unsharp.o
 OBJS-$(CONFIG_VFLIP_FILTER)                  += vf_vflip.o
 
 OBJS-$(CONFIG_BUFFER_FILTER)                 += vsrc_buffer.o
+OBJS-$(CONFIG_COLOR_FILTER)                  += vf_pad.o
 OBJS-$(CONFIG_NULLSRC_FILTER)                += vsrc_nullsrc.o
 
 OBJS-$(CONFIG_NULLSINK_FILTER)               += vsink_nullsink.o

libavfilter/allfilters.c

@@ -48,6 +48,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER (VFLIP,       vflip,       vf);
 
     REGISTER_FILTER (BUFFER,      buffer,      vsrc);
+    REGISTER_FILTER (COLOR,       color,       vsrc);
     REGISTER_FILTER (NULLSRC,     nullsrc,     vsrc);
 
     REGISTER_FILTER (NULLSINK,    nullsink,    vsink);

libavfilter/avfilter.h

@@ -25,7 +25,7 @@
 #include "libavutil/avutil.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  1
-#define LIBAVFILTER_VERSION_MINOR 22
+#define LIBAVFILTER_VERSION_MINOR 23
 #define LIBAVFILTER_VERSION_MICRO  0
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \

libavfilter/vf_pad.c

@@ -21,13 +21,14 @@
 
 /**
  * @file
- * video padding filter
+ * video padding filter and color source
  */
 
 #include "avfilter.h"
 #include "parseutils.h"
 #include "libavutil/pixdesc.h"
 #include "libavutil/colorspace.h"
+#include "libavcodec/avcodec.h"
 
 enum { RED = 0, GREEN, BLUE, ALPHA };
 
@@ -337,3 +338,127 @@ AVFilter avfilter_vf_pad = {
 };
 
 #endif /* CONFIG_PAD_FILTER */
+
+#if CONFIG_COLOR_FILTER
+
+typedef struct {
+    int w, h;
+    uint8_t color[4];
+    AVRational time_base;
+    uint8_t *line[4];
+    int      line_step[4];
+    int hsub, vsub;         ///< chroma subsampling values
+    uint64_t pts;
+} ColorContext;
+
+static av_cold int color_init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+    ColorContext *color = ctx->priv;
+    char color_string[128] = "black";
+    char frame_size  [128] = "320x240";
+    char frame_rate  [128] = "25";
+    AVRational frame_rate_q;
+    int ret;
+
+    if (args)
+        sscanf(args, "%127[^:]:%127[^:]:%127s", color_string, frame_size, frame_rate);
+
+    if (av_parse_video_frame_size(&color->w, &color->h, frame_size) < 0) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid frame size: %s\n", frame_size);
+        return AVERROR(EINVAL);
+    }
+
+    if (av_parse_video_frame_rate(&frame_rate_q, frame_rate) < 0 ||
+        frame_rate_q.den <= 0 || frame_rate_q.num <= 0) {
+        av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: %s\n", frame_rate);
+        return AVERROR(EINVAL);
+    }
+    color->time_base.num = frame_rate_q.den;
+    color->time_base.den = frame_rate_q.num;
+
+    if ((ret = av_parse_color(color->color, color_string, ctx)) < 0)
+        return ret;
+
+    return 0;
+}
+
+static av_cold void color_uninit(AVFilterContext *ctx)
+{
+    ColorContext *color = ctx->priv;
+    int i;
+
+    for (i = 0; i < 4; i++) {
+        av_freep(&color->line[i]);
+        color->line_step[i] = 0;
+    }
+}
+
+static int color_config_props(AVFilterLink *inlink)
+{
+    AVFilterContext *ctx = inlink->src;
+    ColorContext *color = ctx->priv;
+    uint8_t rgba_color[4];
+    int is_packed_rgba;
+    const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
+
+    color->hsub = pix_desc->log2_chroma_w;
+    color->vsub = pix_desc->log2_chroma_h;
+
+    color->w &= ~((1 << color->hsub) - 1);
+    color->h &= ~((1 << color->vsub) - 1);
+    if (avcodec_check_dimensions(ctx, color->w, color->h) < 0)
+        return AVERROR(EINVAL);
+
+    memcpy(rgba_color, color->color, sizeof(rgba_color));
+    fill_line_with_color(color->line, color->line_step, color->w, color->color,
+                         inlink->format, rgba_color, &is_packed_rgba);
+
+    av_log(ctx, AV_LOG_INFO, "w:%d h:%d r:%d/%d color:0x%02x%02x%02x%02x[%s]\n",
+           color->w, color->h, color->time_base.den, color->time_base.num,
+           color->color[0], color->color[1], color->color[2], color->color[3],
+           is_packed_rgba ? "rgba" : "yuva");
+    inlink->w = color->w;
+    inlink->h = color->h;
+
+    return 0;
+}
+
+static int color_request_frame(AVFilterLink *link)
+{
+    ColorContext *color = link->src->priv;
+    AVFilterPicRef *picref = avfilter_get_video_buffer(link, AV_PERM_WRITE, color->w, color->h);
+    picref->pixel_aspect = (AVRational) {1, 1};
+    picref->pts          = av_rescale_q(color->pts++, color->time_base, AV_TIME_BASE_Q);
+    picref->pos          = 0;
+
+    avfilter_start_frame(link, avfilter_ref_pic(picref, ~0));
+    draw_rectangle(picref,
+                   color->line, color->line_step, color->hsub, color->vsub,
+                   0, 0, color->w, color->h);
+    avfilter_draw_slice(link, 0, color->h, 1);
+    avfilter_end_frame(link);
+    avfilter_unref_pic(picref);
+
+    return 0;
+}
+
+AVFilter avfilter_vsrc_color = {
+    .name        = "color",
+    .description = NULL_IF_CONFIG_SMALL("Provide an uniformly colored input, syntax is: [color[:size[:rate]]]"),
+
+    .priv_size = sizeof(ColorContext),
+    .init      = color_init,
+    .uninit    = color_uninit,
+
+    .query_formats = query_formats,
+
+    .inputs    = (AVFilterPad[]) {{ .name = NULL}},
+
+    .outputs   = (AVFilterPad[]) {{ .name            = "default",
+                                    .type            = CODEC_TYPE_VIDEO,
+                                    .request_frame   = color_request_frame,
+                                    .config_props    = color_config_props },
+                                  { .name = NULL}},
+};
+
+#endif /* CONFIG_COLOR_FILTER */