[FFmpeg-devel] [PATCH] blend filter
Paul B Mahol
onemda at gmail.com
Wed Feb 20 11:15:50 CET 2013
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
doc/filters.texi | 107 +++++++++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/vf_blend.c | 474 +++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 583 insertions(+)
create mode 100644 libavfilter/vf_blend.c
diff --git a/doc/filters.texi b/doc/filters.texi
index 43bfd9c..2d4af95 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -1778,6 +1778,113 @@ threshold, and defaults to 98.
@var{threshold} is the threshold below which a pixel value is
considered black, and defaults to 32.
+ at section blend
+
+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.
+
+This filter accepts a list of options in the form of @var{key}=@var{value}
+pairs separated by ":". A description of the accepted options follows.
+
+ at table @option
+ at item c0_mode
+ at item c1_mode
+ at item c2_mode
+ at item c3_mode
+ at item all_mode
+Set blend mode for specific pixel component or all pixel components in case
+of @var{all_mode}. Default value is @code{normal}.
+
+Available values for component modes are:
+ at table @samp
+ at item addition
+ at item and
+ at item average
+ at item burn
+ at item darken
+ at item difference
+ at item divide
+ at item dodge
+ at item exclusion
+ at item hardlight
+ at item lighten
+ at item multiply
+ at item negation
+ at item normal
+ at item or
+ at item overlay
+ at item phoenix
+ at item pinlight
+ at item reflect
+ at item screen
+ at item softlight
+ at item subtract
+ at item vividlight
+ at item xor
+ at end table
+
+ at item c0_opacity
+ at item c1_opacity
+ at item c2_opacity
+ at item c3_opacity
+ at item all_opacity
+Set blend opacity for specific pixel component or all pixel components in case
+of @var{all_expr}. Only used in combination with pixel component blend modes.
+
+ at item c0_expr
+ at item c1_expr
+ at item c2_expr
+ at item c3_expr
+ at item all_expr
+Set blend expression for specific pixel component or all pixel components in case
+of @var{all_expr}. Note that related mode options will be ignored if those are set.
+
+The expressions can use the following variables:
+
+ at table @option
+ at item X
+ at item Y
+The coordinates of the current sample.
+
+ at item W
+ at item H
+The width and height of currently filtered plane.
+
+ at item SW
+ at item SH
+Width and height scale depending on the currently filtered plane. It is the
+ratio between the corresponding luma plane number of pixels and the current
+plane ones. E.g. for YUV4:2:0 the values are @code{1,1} for the luma plane, and
+ at code{0.5,0.5} for chroma planes.
+
+ at item T
+Time of the current frame, expressed in seconds.
+
+ at item A
+Value of pixel component at current location for first video frame (top layer).
+
+ at item B
+Value of pixel component at current location for second video frame (bottom layer).
+ at end table
+ at end table
+
+ at itemize
+
+ at item
+Transition from bottom layer to top layer in first 10 seconds:
+ at example
+blend=all_expr=A*(if(gte(T\,10)\,1\,mod(T\,10)/10))+B*(1-(if(gte(T\,10)\,1\,mod(T\,10)/10)))
+ at end example
+
+ at item
+Checkerboard effect:
+ at example
+blend=all_expr=if(eq(mod(X\,2)\,mod(Y\,2))\,A\,B)
+ at end example
+ at end itemize
+
@section boxblur
Apply boxblur algorithm to the input video.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 2449da4..04ed8b8 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -100,6 +100,7 @@ OBJS-$(CONFIG_ALPHAMERGE_FILTER) += vf_alphamerge.o
OBJS-$(CONFIG_BBOX_FILTER) += bbox.o vf_bbox.o
OBJS-$(CONFIG_BLACKDETECT_FILTER) += vf_blackdetect.o
OBJS-$(CONFIG_BLACKFRAME_FILTER) += vf_blackframe.o
+OBJS-$(CONFIG_BLEND_FILTER) += vf_blend.o
OBJS-$(CONFIG_BOXBLUR_FILTER) += vf_boxblur.o
OBJS-$(CONFIG_COLORMATRIX_FILTER) += vf_colormatrix.o
OBJS-$(CONFIG_COPY_FILTER) += vf_copy.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 61f29ff..f05f8ae 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -94,6 +94,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(BBOX, bbox, vf);
REGISTER_FILTER(BLACKDETECT, blackdetect, vf);
REGISTER_FILTER(BLACKFRAME, blackframe, vf);
+ REGISTER_FILTER(BLEND, blend, vf);
REGISTER_FILTER(BOXBLUR, boxblur, vf);
REGISTER_FILTER(COLORMATRIX, colormatrix, vf);
REGISTER_FILTER(COPY, copy, vf);
diff --git a/libavfilter/vf_blend.c b/libavfilter/vf_blend.c
new file mode 100644
index 0000000..e95f268
--- /dev/null
+++ b/libavfilter/vf_blend.c
@@ -0,0 +1,474 @@
+/*
+ * Copyright (c) 2013 Paul B Mahol
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/imgutils.h"
+#include "libavutil/eval.h"
+#include "libavutil/opt.h"
+#include "libavutil/pixfmt.h"
+#include "avfilter.h"
+#include "bufferqueue.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+
+#define TOP 0
+#define BOTTOM 1
+
+enum BlendMode {
+ BLEND_UNSET = -1,
+ BLEND_NORMAL,
+ BLEND_ADDITION,
+ BLEND_AND,
+ BLEND_AVERAGE,
+ BLEND_BURN,
+ BLEND_DARKEN,
+ BLEND_DIFFERENCE,
+ BLEND_DIVIDE,
+ BLEND_DODGE,
+ BLEND_EXCLUSION,
+ BLEND_HARDLIGHT,
+ BLEND_LIGHTEN,
+ BLEND_MULTIPLY,
+ BLEND_NEGATION,
+ BLEND_OR,
+ BLEND_OVERLAY,
+ BLEND_PHOENIX,
+ BLEND_PINLIGHT,
+ BLEND_REFLECT,
+ BLEND_SCREEN,
+ BLEND_SOFTLIGHT,
+ BLEND_SUBTRACT,
+ BLEND_VIVIDLIGHT,
+ BLEND_XOR,
+ BLEND_NB
+};
+
+static const char *const var_names[] = { "X", "Y", "W", "H", "SW", "SH", "T", "A", "B", NULL };
+enum { VAR_X, VAR_Y, VAR_W, VAR_H, VAR_SW, VAR_SH, VAR_T, VAR_TOP, VAR_BOTTOM, VAR_VARS_NB };
+
+typedef struct FilterParams {
+ enum BlendMode mode;
+ double values[VAR_VARS_NB];
+ double opacity;
+ AVExpr *e;
+ char *expr_str;
+ void (*blend)(const uint8_t *top, int top_linesize,
+ const uint8_t *bottom, int bottom_linesize,
+ uint8_t *dst, int dst_linesize,
+ int width, int height, struct FilterParams *param);
+} FilterParams;
+
+typedef struct {
+ const AVClass *class;
+ struct FFBufQueue queue_top;
+ struct FFBufQueue queue_bottom;
+ int hsub, vsub; ///< chroma subsampling values
+ int frame_requested;
+ char *all_expr;
+ enum BlendMode all_mode;
+ double all_opacity;
+
+ FilterParams params[4];
+} BlendContext;
+
+#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" },
+ { "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},
+ { NULL },
+};
+
+AVFILTER_DEFINE_CLASS(blend);
+
+static void blend_normal(const uint8_t *top, int top_linesize,
+ const uint8_t *bottom, int bottom_linesize,
+ uint8_t *dst, int dst_linesize,
+ int width, int height, FilterParams *param)
+{
+ av_image_copy_plane(dst, dst_linesize, top, top_linesize, width, height);
+}
+
+#define DEFINE_BLEND(name, expr) \
+static void blend_## name(const uint8_t *top, int top_linesize, \
+ const uint8_t *bottom, int bottom_linesize, \
+ uint8_t *dst, int dst_linesize, \
+ int width, int height, FilterParams *param) \
+{ \
+ double opacity = param->opacity; \
+ int i, j; \
+ \
+ for (i = 0; i < height; i++) { \
+ for (j = 0; j < width; j++) { \
+ dst[j] = top[j] + ((expr) - top[j]) * opacity; \
+ } \
+ dst += dst_linesize; \
+ top += top_linesize; \
+ bottom += bottom_linesize; \
+ } \
+}
+
+#define A top[j]
+#define B bottom[j]
+
+#define MULTIPLY(x, a, b) (x * ((a * b) / 255))
+#define SCREEN(x, a, b) (255 - x * ((255 - a) * (255 - b) / 255))
+#define BURN(a, b) ((a == 0) ? a : FFMAX(0, 255 - ((255 - b) << 8) / a))
+#define DODGE(a, b) ((a == 255) ? a : FFMIN(255, ((b << 8) / (255 - a))))
+
+DEFINE_BLEND(addition, FFMIN(255, A + B))
+DEFINE_BLEND(average, (A + B) / 2)
+DEFINE_BLEND(subtract, FFMAX(0, A - B))
+DEFINE_BLEND(multiply, MULTIPLY(1, A, B))
+DEFINE_BLEND(negation, 255 - FFABS(255 - A - B))
+DEFINE_BLEND(difference, FFABS(A - B))
+DEFINE_BLEND(screen, SCREEN(1, A, B))
+DEFINE_BLEND(overlay, (A < 128) ? MULTIPLY(2, A, B) : SCREEN(2, A, B))
+DEFINE_BLEND(hardlight, (B < 128) ? MULTIPLY(2, B, A) : SCREEN(2, B, A))
+DEFINE_BLEND(darken, FFMIN(A, B))
+DEFINE_BLEND(lighten, FFMAX(A, B))
+DEFINE_BLEND(divide, ((float)A / ((float)B) * 255))
+DEFINE_BLEND(dodge, DODGE(A, B))
+DEFINE_BLEND(burn, BURN(A, B))
+DEFINE_BLEND(softlight, (A > 127) ? B + (255 - B) * (A - 127.5) / 127.5 * (0.5 - FFABS(B - 127.5) / 255): B - B * ((127.5 - A) / 127.5) * (0.5 - FFABS(B - 127.5)/255))
+DEFINE_BLEND(exclusion, A + B - 2 * A * B / 255)
+DEFINE_BLEND(pinlight, (B < 128) ? FFMIN(A, 2 * B) : FFMAX(A, 2 * (B - 128)))
+DEFINE_BLEND(phoenix, FFMIN(A, B) - FFMAX(A, B) + 255)
+DEFINE_BLEND(reflect, (B == 255) ? B : FFMIN(255, (A * A / (255 - B))))
+DEFINE_BLEND(and, A & B)
+DEFINE_BLEND(or, A | B)
+DEFINE_BLEND(xor, A ^ B)
+DEFINE_BLEND(vividlight, (B < 128) ? BURN(A, 2 * B) : DODGE(A, 2 * (B - 128)))
+
+static void blend_expr(const uint8_t *top, int top_linesize,
+ const uint8_t *bottom, int bottom_linesize,
+ uint8_t *dst, int dst_linesize,
+ int width, int height,
+ FilterParams *param)
+{
+ AVExpr *e = param->e;
+ double *values = param->values;
+ int y, x;
+
+ for (y = 0; y < height; y++) {
+ values[VAR_Y] = y;
+ for (x = 0; x < width; x++) {
+ values[VAR_X] = x;
+ values[VAR_TOP] = top[x];
+ values[VAR_BOTTOM] = bottom[x];
+ dst[x] = av_expr_eval(e, values, NULL);
+ }
+ dst += dst_linesize;
+ top += top_linesize;
+ bottom += bottom_linesize;
+ }
+}
+
+static av_cold int init(AVFilterContext *ctx, const char *args)
+{
+ BlendContext *b = ctx->priv;
+ int ret, plane;
+
+ b->class = &blend_class;
+ av_opt_set_defaults(b);
+
+ if ((ret = av_set_options_string(b, args, "=", ":")) < 0)
+ return ret;
+
+ for (plane = 0; plane < FF_ARRAY_ELEMS(b->params); plane++) {
+ FilterParams *param = &b->params[plane];
+
+ if (b->all_mode >= 0)
+ param->mode = b->all_mode;
+ if (b->all_opacity < 1)
+ param->opacity = b->all_opacity;
+
+ switch (param->mode) {
+ case BLEND_ADDITION: param->blend = blend_addition; break;
+ case BLEND_AND: param->blend = blend_and; break;
+ case BLEND_AVERAGE: param->blend = blend_average; break;
+ case BLEND_BURN: param->blend = blend_burn; break;
+ case BLEND_DARKEN: param->blend = blend_darken; break;
+ case BLEND_DIFFERENCE: param->blend = blend_difference; break;
+ case BLEND_DIVIDE: param->blend = blend_divide; break;
+ case BLEND_DODGE: param->blend = blend_dodge; break;
+ case BLEND_EXCLUSION: param->blend = blend_exclusion; break;
+ case BLEND_HARDLIGHT: param->blend = blend_hardlight; break;
+ case BLEND_LIGHTEN: param->blend = blend_lighten; break;
+ case BLEND_MULTIPLY: param->blend = blend_multiply; break;
+ case BLEND_NEGATION: param->blend = blend_negation; break;
+ case BLEND_NORMAL: param->blend = blend_normal; break;
+ case BLEND_OR: param->blend = blend_or; break;
+ case BLEND_OVERLAY: param->blend = blend_overlay; break;
+ case BLEND_PHOENIX: param->blend = blend_phoenix; break;
+ case BLEND_PINLIGHT: param->blend = blend_pinlight; break;
+ case BLEND_REFLECT: param->blend = blend_reflect; break;
+ case BLEND_SCREEN: param->blend = blend_screen; break;
+ case BLEND_SOFTLIGHT: param->blend = blend_softlight; break;
+ case BLEND_SUBTRACT: param->blend = blend_subtract; break;
+ case BLEND_VIVIDLIGHT: param->blend = blend_vividlight; break;
+ case BLEND_XOR: param->blend = blend_xor; break;
+ }
+
+ if (b->all_expr && !param->expr_str) {
+ param->expr_str = av_strdup(b->all_expr);
+ if (!param->expr_str)
+ return AVERROR(ENOMEM);
+ }
+ if (param->expr_str) {
+ ret = av_expr_parse(¶m->e, param->expr_str, var_names,
+ NULL, NULL, NULL, NULL, 0, ctx);
+ if (ret < 0)
+ return ret;
+ param->blend = blend_expr;
+ }
+ }
+
+ return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum AVPixelFormat pix_fmts[] = {
+ AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
+ AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P,
+ AV_PIX_FMT_GBRP, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE
+ };
+
+ ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
+ return 0;
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ AVFilterLink *toplink = ctx->inputs[TOP];
+ AVFilterLink *bottomlink = ctx->inputs[BOTTOM];
+
+ if (toplink->format != bottomlink->format) {
+ av_log(ctx, AV_LOG_ERROR, "inputs must be of same pixel format\n");
+ return AVERROR(EINVAL);
+ }
+ if (toplink->w != bottomlink->w ||
+ toplink->h != bottomlink->h ||
+ toplink->sample_aspect_ratio.num != bottomlink->sample_aspect_ratio.num ||
+ toplink->sample_aspect_ratio.den != bottomlink->sample_aspect_ratio.den) {
+ av_log(ctx, AV_LOG_ERROR, "First input link %s parameters "
+ "(size %dx%d, SAR %d:%d) do not match the corresponding "
+ "second input link %s parameters (%dx%d, SAR %d:%d)\n",
+ ctx->input_pads[TOP].name, toplink->w, toplink->h,
+ toplink->sample_aspect_ratio.num,
+ toplink->sample_aspect_ratio.den,
+ ctx->input_pads[BOTTOM].name, bottomlink->w, bottomlink->h,
+ bottomlink->sample_aspect_ratio.num,
+ bottomlink->sample_aspect_ratio.den);
+ return AVERROR(EINVAL);
+ }
+
+ outlink->w = toplink->w;
+ outlink->h = bottomlink->h;
+ outlink->time_base = toplink->time_base;
+ outlink->sample_aspect_ratio = toplink->sample_aspect_ratio;
+ outlink->frame_rate = toplink->frame_rate;
+ return 0;
+}
+
+static int config_input_top(AVFilterLink *inlink)
+{
+ BlendContext *b = inlink->dst->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;
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ BlendContext *b = ctx->priv;
+ int i;
+
+ av_opt_free(b);
+ ff_bufqueue_discard_all(&b->queue_top);
+ ff_bufqueue_discard_all(&b->queue_bottom);
+
+ for (i = 0; i < FF_ARRAY_ELEMS(b->params); i++)
+ av_expr_free(b->params[i].e);
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ BlendContext *b = ctx->priv;
+ int in, ret;
+
+ b->frame_requested = 1;
+ while (b->frame_requested) {
+ in = ff_bufqueue_peek(&b->queue_top, TOP) ? BOTTOM : TOP;
+ ret = ff_request_frame(ctx->inputs[in]);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+static void blend_frame(AVFilterContext *ctx,
+ AVFilterBufferRef *top_buf,
+ AVFilterBufferRef *bottom_buf,
+ AVFilterBufferRef *dst_buf)
+{
+ BlendContext *b = ctx->priv;
+ AVFilterLink *inlink = ctx->inputs[0];
+ FilterParams *param;
+ int plane;
+
+ for (plane = 0; dst_buf->data[plane]; plane++) {
+ int hsub = plane == 1 || plane == 2 ? b->hsub : 0;
+ int vsub = plane == 1 || plane == 2 ? b->vsub : 0;
+ int outw = dst_buf->video->w >> hsub;
+ int outh = dst_buf->video->h >> vsub;
+ uint8_t *dst = dst_buf->data[plane];
+ uint8_t *top = top_buf->data[plane];
+ uint8_t *bottom = bottom_buf->data[plane];
+
+ param = &b->params[plane];
+ param->values[VAR_T] = dst_buf->pts == AV_NOPTS_VALUE ? NAN : dst_buf->pts * av_q2d(inlink->time_base);
+ param->values[VAR_W] = outw;
+ param->values[VAR_H] = outh;
+ param->values[VAR_SW] = outw / dst_buf->video->w;
+ param->values[VAR_SH] = outh / dst_buf->video->h;
+ param->blend(top, top_buf->linesize[plane],
+ bottom, bottom_buf->linesize[plane],
+ dst, dst_buf->linesize[plane], outw, outh, param);
+ }
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *buf)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AVFilterLink *outlink = ctx->outputs[0];
+ BlendContext *b = ctx->priv;
+
+ int ret = AVERROR(EAGAIN);
+ int is_bottom = (inlink == ctx->inputs[BOTTOM]);
+ struct FFBufQueue *queue =
+ (is_bottom ? &b->queue_bottom : &b->queue_top);
+ ff_bufqueue_add(ctx, queue, buf);
+
+ while (1) {
+ AVFilterBufferRef *top_buf, *bottom_buf, *out_buf;
+
+ if (!ff_bufqueue_peek(&b->queue_top, TOP) ||
+ !ff_bufqueue_peek(&b->queue_bottom, BOTTOM)) break;
+
+ top_buf = ff_bufqueue_get(&b->queue_top);
+ bottom_buf = ff_bufqueue_get(&b->queue_bottom);
+
+ out_buf = ff_get_video_buffer(outlink, AV_PERM_WRITE,
+ outlink->w, outlink->h);
+ if (!out_buf) {
+ return AVERROR(ENOMEM);
+ }
+ avfilter_copy_buffer_ref_props(out_buf, top_buf);
+
+ b->frame_requested = 0;
+ blend_frame(ctx, top_buf, bottom_buf, out_buf);
+ ret = ff_filter_frame(ctx->outputs[0], out_buf);
+ avfilter_unref_buffer(top_buf);
+ avfilter_unref_buffer(bottom_buf);
+ }
+ return ret;
+}
+
+static const AVFilterPad blend_inputs[] = {
+ {
+ .name = "top",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_input_top,
+ .filter_frame = filter_frame,
+ .min_perms = AV_PERM_READ | AV_PERM_PRESERVE,
+ },{
+ .name = "bottom",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .filter_frame = filter_frame,
+ .min_perms = AV_PERM_READ | AV_PERM_PRESERVE,
+ },
+ { NULL }
+};
+
+static const AVFilterPad blend_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_output,
+ .request_frame = request_frame,
+ },
+ { NULL }
+};
+
+AVFilter avfilter_vf_blend = {
+ .name = "blend",
+ .description = NULL_IF_CONFIG_SMALL("Blend two video frames into each other."),
+ .init = init,
+ .uninit = uninit,
+ .priv_size = sizeof(BlendContext),
+ .query_formats = query_formats,
+ .inputs = blend_inputs,
+ .outputs = blend_outputs,
+ .priv_class = &blend_class,
+};
--
1.7.11.4
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