lavfi: add tblend filter

6 files changed, 142 insertions, 49 deletions

diff --git a/Changelog b/Changelog
index a8c802f077..37ce0f0a14 100644
--- a/Changelog
+++ b/Changelog
@@ -8,6 +8,7 @@ version <next>:
 - RIFX format for *.wav files
 - RTP/mpegts muxer
 - non continuous cache protocol support
+- tblend filter
 
 
 version 2.5:
diff --git a/doc/filters.texi b/doc/filters.texi
index aaa3083a70..261fd24682 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -2634,13 +2634,17 @@ The threshold below which a pixel value is considered black; it defaults to
 
 @end table
 
-@section blend
+@section blend, tblend
 
 Blend two video frames into each other.
 
-It takes two input streams and outputs one stream, the first input is the
-"top" layer and second input is "bottom" layer.
-Output terminates when shortest input terminates.
+The @code{blend} filter takes two input streams and outputs one
+stream, the first input is the "top" layer and second input is
+"bottom" layer.  Output terminates when shortest input terminates.
+
+The @code{tblend} (time blend) filter takes two consecutive frames
+from one single stream, and outputs the result obtained by blending
+the new frame on top of the old frame.
 
 A description of the accepted options follows.
 
@@ -2730,11 +2734,13 @@ Value of pixel component at current location for second video frame (bottom laye
 @end table
 
 @item shortest
-Force termination when the shortest input terminates. Default is @code{0}.
+Force termination when the shortest input terminates. Default is
+@code{0}. This option is only defined for the @code{blend} filter.
+
 @item repeatlast
 Continue applying the last bottom frame after the end of the stream. A value of
 @code{0} disable the filter after the last frame of the bottom layer is reached.
-Default is @code{1}.
+Default is @code{1}. This option is only defined for the @code{blend} filter.
 @end table
 
 @subsection Examples
@@ -2769,6 +2775,12 @@ Apply uncover up-left effect:
 @example
 blend=all_expr='if(gte(T*SH*40+Y,H)*gte((T*40*SW+X)*W/H,W),A,B)'
 @end example
+
+@item
+Display differences between the current and the previous frame:
+@example
+tblend=all_mode=difference128
+@end example
 @end itemize
 
 @section boxblur
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index cdcbe0ac91..0ead6c53ad 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -188,6 +188,7 @@ OBJS-$(CONFIG_STEREO3D_FILTER)               += vf_stereo3d.o
 OBJS-$(CONFIG_SUBTITLES_FILTER)              += vf_subtitles.o
 OBJS-$(CONFIG_SUPER2XSAI_FILTER)             += vf_super2xsai.o
 OBJS-$(CONFIG_SWAPUV_FILTER)                 += vf_swapuv.o
+OBJS-$(CONFIG_TBLEND_FILTER)                 += vf_blend.o
 OBJS-$(CONFIG_TELECINE_FILTER)               += vf_telecine.o
 OBJS-$(CONFIG_THUMBNAIL_FILTER)              += vf_thumbnail.o
 OBJS-$(CONFIG_TILE_FILTER)                   += vf_tile.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 2911ed9722..6543629d79 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -203,6 +203,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(SUBTITLES,      subtitles,      vf);
     REGISTER_FILTER(SUPER2XSAI,     super2xsai,     vf);
     REGISTER_FILTER(SWAPUV,         swapuv,         vf);
+    REGISTER_FILTER(TBLEND,         tblend,         vf);
     REGISTER_FILTER(TELECINE,       telecine,       vf);
     REGISTER_FILTER(THUMBNAIL,      thumbnail,      vf);
     REGISTER_FILTER(TILE,           tile,           vf);
diff --git a/libavfilter/version.h b/libavfilter/version.h
index 4afcbe0f80..50967f4340 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,8 +30,8 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR  5
-#define LIBAVFILTER_VERSION_MINOR  5
-#define LIBAVFILTER_VERSION_MICRO 102
+#define LIBAVFILTER_VERSION_MINOR  6
+#define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
                                                LIBAVFILTER_VERSION_MINOR, \
diff --git a/libavfilter/vf_blend.c b/libavfilter/vf_blend.c
index 1b3ba95b1a..6dbf1496d6 100644
--- a/libavfilter/vf_blend.c
+++ b/libavfilter/vf_blend.c
@@ -96,52 +96,57 @@ typedef struct {
     double all_opacity;
 
     FilterParams params[4];
+    int tblend;
+    AVFrame *prev_frame;        /* only used with tblend */
 } BlendContext;
 
+#define COMMON_OPTIONS \
+    { "c0_mode", "set component #0 blend mode", OFFSET(params[0].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},\
+    { "c1_mode", "set component #1 blend mode", OFFSET(params[1].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},\
+    { "c2_mode", "set component #2 blend mode", OFFSET(params[2].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},\
+    { "c3_mode", "set component #3 blend mode", OFFSET(params[3].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},\
+    { "all_mode", "set blend mode for all components", OFFSET(all_mode), AV_OPT_TYPE_INT, {.i64=-1},-1, BLEND_NB-1, FLAGS, "mode"},\
+    { "addition",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_ADDITION},   0, 0, FLAGS, "mode" },\
+    { "and",        "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_AND},        0, 0, FLAGS, "mode" },\
+    { "average",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_AVERAGE},    0, 0, FLAGS, "mode" },\
+    { "burn",       "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_BURN},       0, 0, FLAGS, "mode" },\
+    { "darken",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DARKEN},     0, 0, FLAGS, "mode" },\
+    { "difference", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIFFERENCE}, 0, 0, FLAGS, "mode" },\
+    { "difference128", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIFFERENCE128}, 0, 0, FLAGS, "mode" },\
+    { "divide",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIVIDE},     0, 0, FLAGS, "mode" },\
+    { "dodge",      "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DODGE},      0, 0, FLAGS, "mode" },\
+    { "exclusion",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_EXCLUSION},  0, 0, FLAGS, "mode" },\
+    { "hardlight",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_HARDLIGHT},  0, 0, FLAGS, "mode" },\
+    { "lighten",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_LIGHTEN},    0, 0, FLAGS, "mode" },\
+    { "multiply",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_MULTIPLY},   0, 0, FLAGS, "mode" },\
+    { "negation",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_NEGATION},   0, 0, FLAGS, "mode" },\
+    { "normal",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_NORMAL},     0, 0, FLAGS, "mode" },\
+    { "or",         "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_OR},         0, 0, FLAGS, "mode" },\
+    { "overlay",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_OVERLAY},    0, 0, FLAGS, "mode" },\
+    { "phoenix",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_PHOENIX},    0, 0, FLAGS, "mode" },\
+    { "pinlight",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_PINLIGHT},   0, 0, FLAGS, "mode" },\
+    { "reflect",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_REFLECT},    0, 0, FLAGS, "mode" },\
+    { "screen",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SCREEN},     0, 0, FLAGS, "mode" },\
+    { "softlight",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SOFTLIGHT},  0, 0, FLAGS, "mode" },\
+    { "subtract",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SUBTRACT},   0, 0, FLAGS, "mode" },\
+    { "vividlight", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_VIVIDLIGHT}, 0, 0, FLAGS, "mode" },\
+    { "xor",        "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_XOR},        0, 0, FLAGS, "mode" },\
+    { "c0_expr",  "set color component #0 expression", OFFSET(params[0].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },\
+    { "c1_expr",  "set color component #1 expression", OFFSET(params[1].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },\
+    { "c2_expr",  "set color component #2 expression", OFFSET(params[2].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },\
+    { "c3_expr",  "set color component #3 expression", OFFSET(params[3].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },\
+    { "all_expr", "set expression for all color components", OFFSET(all_expr), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },\
+    { "c0_opacity",  "set color component #0 opacity", OFFSET(params[0].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },\
+    { "c1_opacity",  "set color component #1 opacity", OFFSET(params[1].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },\
+    { "c2_opacity",  "set color component #2 opacity", OFFSET(params[2].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },\
+    { "c3_opacity",  "set color component #3 opacity", OFFSET(params[3].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },\
+    { "all_opacity", "set opacity for all color components", OFFSET(all_opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS}
+
 #define OFFSET(x) offsetof(BlendContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
 static const AVOption blend_options[] = {
-    { "c0_mode", "set component #0 blend mode", OFFSET(params[0].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
-    { "c1_mode", "set component #1 blend mode", OFFSET(params[1].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
-    { "c2_mode", "set component #2 blend mode", OFFSET(params[2].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
-    { "c3_mode", "set component #3 blend mode", OFFSET(params[3].mode), AV_OPT_TYPE_INT, {.i64=0}, 0, BLEND_NB-1, FLAGS, "mode"},
-    { "all_mode", "set blend mode for all components", OFFSET(all_mode), AV_OPT_TYPE_INT, {.i64=-1},-1, BLEND_NB-1, FLAGS, "mode"},
-    { "addition",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_ADDITION},   0, 0, FLAGS, "mode" },
-    { "and",        "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_AND},        0, 0, FLAGS, "mode" },
-    { "average",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_AVERAGE},    0, 0, FLAGS, "mode" },
-    { "burn",       "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_BURN},       0, 0, FLAGS, "mode" },
-    { "darken",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DARKEN},     0, 0, FLAGS, "mode" },
-    { "difference", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIFFERENCE}, 0, 0, FLAGS, "mode" },
-    { "difference128", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIFFERENCE128}, 0, 0, FLAGS, "mode" },
-    { "divide",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DIVIDE},     0, 0, FLAGS, "mode" },
-    { "dodge",      "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_DODGE},      0, 0, FLAGS, "mode" },
-    { "exclusion",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_EXCLUSION},  0, 0, FLAGS, "mode" },
-    { "hardlight",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_HARDLIGHT},  0, 0, FLAGS, "mode" },
-    { "lighten",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_LIGHTEN},    0, 0, FLAGS, "mode" },
-    { "multiply",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_MULTIPLY},   0, 0, FLAGS, "mode" },
-    { "negation",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_NEGATION},   0, 0, FLAGS, "mode" },
-    { "normal",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_NORMAL},     0, 0, FLAGS, "mode" },
-    { "or",         "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_OR},         0, 0, FLAGS, "mode" },
-    { "overlay",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_OVERLAY},    0, 0, FLAGS, "mode" },
-    { "phoenix",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_PHOENIX},    0, 0, FLAGS, "mode" },
-    { "pinlight",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_PINLIGHT},   0, 0, FLAGS, "mode" },
-    { "reflect",    "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_REFLECT},    0, 0, FLAGS, "mode" },
-    { "screen",     "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SCREEN},     0, 0, FLAGS, "mode" },
-    { "softlight",  "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SOFTLIGHT},  0, 0, FLAGS, "mode" },
-    { "subtract",   "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_SUBTRACT},   0, 0, FLAGS, "mode" },
-    { "vividlight", "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_VIVIDLIGHT}, 0, 0, FLAGS, "mode" },
-    { "xor",        "", 0, AV_OPT_TYPE_CONST, {.i64=BLEND_XOR},        0, 0, FLAGS, "mode" },
-    { "c0_expr",  "set color component #0 expression", OFFSET(params[0].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
-    { "c1_expr",  "set color component #1 expression", OFFSET(params[1].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
-    { "c2_expr",  "set color component #2 expression", OFFSET(params[2].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
-    { "c3_expr",  "set color component #3 expression", OFFSET(params[3].expr_str), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
-    { "all_expr", "set expression for all color components", OFFSET(all_expr), AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
-    { "c0_opacity",  "set color component #0 opacity", OFFSET(params[0].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
-    { "c1_opacity",  "set color component #1 opacity", OFFSET(params[1].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
-    { "c2_opacity",  "set color component #2 opacity", OFFSET(params[2].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
-    { "c3_opacity",  "set color component #3 opacity", OFFSET(params[3].opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS },
-    { "all_opacity", "set opacity for all color components", OFFSET(all_opacity), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0, 1, FLAGS},
+    COMMON_OPTIONS,
     { "shortest",    "force termination when the shortest input terminates", OFFSET(dinput.shortest), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS },
     { "repeatlast",  "repeat last bottom frame", OFFSET(dinput.repeatlast), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS },
     { NULL }
@@ -288,7 +293,8 @@ static AVFrame *blend_frame(AVFilterContext *ctx, AVFrame *top_buf,
         ctx->internal->execute(ctx, filter_slice, &td, NULL, FFMIN(outh, ctx->graph->nb_threads));
     }
 
-    av_frame_free(&top_buf);
+    if (!b->tblend)
+        av_frame_free(&top_buf);
 
     return dst_buf;
 }
@@ -298,6 +304,8 @@ static av_cold int init(AVFilterContext *ctx)
     BlendContext *b = ctx->priv;
     int ret, plane;
 
+    b->tblend = !strcmp(ctx->filter->name, "tblend");
+
     for (plane = 0; plane < FF_ARRAY_ELEMS(b->params); plane++) {
         FilterParams *param = &b->params[plane];
 
@@ -416,6 +424,8 @@ static av_cold void uninit(AVFilterContext *ctx)
     int i;
 
     ff_dualinput_uninit(&b->dinput);
+    av_freep(&b->prev_frame);
+
     for (i = 0; i < FF_ARRAY_ELEMS(b->params); i++)
         av_expr_free(b->params[i].e);
 }
@@ -467,3 +477,71 @@ AVFilter ff_vf_blend = {
     .priv_class    = &blend_class,
     .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL | AVFILTER_FLAG_SLICE_THREADS,
 };
+
+static int tblend_config_output(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    AVFilterLink *inlink = ctx->inputs[0];
+    BlendContext *b = ctx->priv;
+    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
+
+    b->hsub = pix_desc->log2_chroma_w;
+    b->vsub = pix_desc->log2_chroma_h;
+    b->nb_planes = av_pix_fmt_count_planes(inlink->format);
+    outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
+
+    return 0;
+}
+
+static int tblend_filter_frame(AVFilterLink *inlink, AVFrame *frame)
+{
+    BlendContext *b = inlink->dst->priv;
+    AVFilterLink *outlink = inlink->dst->outputs[0];
+
+    if (b->prev_frame) {
+        AVFrame *out = blend_frame(inlink->dst, frame, b->prev_frame);
+        av_frame_free(&b->prev_frame);
+        b->prev_frame = frame;
+        return ff_filter_frame(outlink, out);
+    }
+    b->prev_frame = frame;
+    return 0;
+}
+
+static const AVOption tblend_options[] = {
+    COMMON_OPTIONS,
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(tblend);
+
+static const AVFilterPad tblend_inputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_VIDEO,
+        .filter_frame  = tblend_filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad tblend_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_VIDEO,
+        .config_props  = tblend_config_output,
+    },
+    { NULL }
+};
+
+AVFilter ff_vf_tblend = {
+    .name          = "tblend",
+    .description   = NULL_IF_CONFIG_SMALL("Blend successive frames."),
+    .priv_size     = sizeof(BlendContext),
+    .priv_class    = &blend_class,
+    .query_formats = query_formats,
+    .init          = init,
+    .uninit        = uninit,
+    .inputs        = tblend_inputs,
+    .outputs       = tblend_outputs,
+    .flags         = AVFILTER_FLAG_SLICE_THREADS,
+};