[PATCH 2/2] Port overlay filter from the libavfilter repo (with lots of fixes), adopting Baptiste variant which is simpler and faster.
Stefano Sabatini
stefano.sabatini-lala
Mon Jun 28 19:30:15 CEST 2010
---
doc/filters.texi | 53 +++++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/vf_overlay.c | 379 ++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 434 insertions(+), 0 deletions(-)
create mode 100644 libavfilter/vf_overlay.c
diff --git a/doc/filters.texi b/doc/filters.texi
index 1736bca..55d2265 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -426,6 +426,59 @@ libopencv function @code{cvSmooth}. Refer to the official libopencv
documentation for the exact meaning of the parameters:
@url{http://opencv.willowgarage.com/documentation/c/image_filtering.html}
+ at section overlay
+
+Overlay one video on top of another (see the example in the
+introduction section).
+
+Be aware that frames are taken from each input video in timestamp
+order, hence, if their initial timestamps differ, it is a a good idea
+to pass the two inputs through a @var{setpts=PTS-STARTPTS} filter to
+have them begin in the same zero timestamp, as it does the example for
+the @var{movie} filter.
+
+Parameters to the filter are separated by a colon. The first parameter
+is the x coordinate of the overlay, the second parameter is the y
+coordinate. The parameters need not be constant expressions, but may
+be expressions containing the following parameters:
+
+ at table @option
+ at item main_w, main_h
+main input width and height
+
+ at item W, H
+same as @var{main_w} and @var{main_h}
+
+ at item overlay_w, overlay_h
+overlay input width and height
+
+ at item w, h
+same as @var{overlay_w} and @var{overlay_h}
+ at end table
+
+This can be used in particular for performing watermarking effects, or
+for adding a logo on top of the input video.
+
+Follow some examples:
+
+ at example
+# draw the overlay at 10 pixels from the bottom right
+# corner of the main video.
+overlay=main_w-overlay_w-10:main_h-overlay_h-10
+
+# insert a transparent PNG logo in the bottom left corner of the input
+movie=0:png:logo.png [logo]; [in][logo] overlay=10:main_h-overlay_h-10 [out]
+
+# insert 2 different transparent PNG logos (second logo on bottom right corner):
+movie=0:png:logo1.png [logo1];
+movie=0:png:logo2.png [logo2];
+[in][logo1] overlay=10:H-h-10 [in+logo1];
+[in+logo1][logo2] overlay=W-w-10:H-h-10 [out]
+ at end example
+
+You could chain and add more overlays this way but the efficiency of
+such approach is yet to be tested.
+
@section pad
Add paddings to the input image, and places the original input at the
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 04a1421..dc2690c 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -33,6 +33,7 @@ OBJS-$(CONFIG_HFLIP_FILTER) += vf_hflip.o
OBJS-$(CONFIG_NOFORMAT_FILTER) += vf_format.o
OBJS-$(CONFIG_NULL_FILTER) += vf_null.o
OBJS-$(CONFIG_OCV_SMOOTH_FILTER) += vf_libopencv.o
+OBJS-$(CONFIG_OVERLAY_FILTER) += vf_overlay.o
OBJS-$(CONFIG_PAD_FILTER) += vf_pad.o
OBJS-$(CONFIG_PIXDESCTEST_FILTER) += vf_pixdesctest.o
OBJS-$(CONFIG_PIXELASPECT_FILTER) += vf_aspect.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 5c58c72..3ff0567 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -52,6 +52,7 @@ void avfilter_register_all(void)
REGISTER_FILTER (NOFORMAT, noformat, vf);
REGISTER_FILTER (NULL, null, vf);
REGISTER_FILTER (OCV_SMOOTH, ocv_smooth, vf);
+ REGISTER_FILTER (OVERLAY, overlay, vf);
REGISTER_FILTER (PAD, pad, vf);
REGISTER_FILTER (PIXDESCTEST, pixdesctest, vf);
REGISTER_FILTER (PIXELASPECT, pixelaspect, vf);
diff --git a/libavfilter/vf_overlay.c b/libavfilter/vf_overlay.c
new file mode 100644
index 0000000..11ea939
--- /dev/null
+++ b/libavfilter/vf_overlay.c
@@ -0,0 +1,379 @@
+/*
+ * Copyright (c) 2010 Stefano Sabatini
+ * Copyright (c) 2010 Baptiste Coudurier
+ * Copyright (c) 2007 Bobby Bingham
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * overlay one video on top of another
+ */
+
+#include "avfilter.h"
+#include "libavutil/eval.h"
+#include "libavutil/avstring.h"
+#include "libavutil/pixdesc.h"
+#include "libavcore/imgutils.h"
+#include "internal.h"
+
+static const char *var_names[] = {
+ "E",
+ "PHI",
+ "PI",
+ "main_w", "W", ///< width of the main video
+ "main_h", "H", ///< height of the main video
+ "overlay_w", "w", ///< width of the overlay video
+ "overlay_h", "h", ///< height of the overlay video
+ NULL
+};
+
+enum var_name {
+ VAR_E,
+ VAR_PHI,
+ VAR_PI,
+ VAR_MAIN_W, VAR_MW,
+ VAR_MAIN_H, VAR_MH,
+ VAR_OVERLAY_W, VAR_OW,
+ VAR_OVERLAY_H, VAR_OH,
+ VAR_VARS_NB
+};
+
+#define MAIN 0
+#define OVERLAY 1
+#define PREV 0
+#define QUEUED 1
+
+typedef struct {
+ int x, y; ///< position of overlayed picture
+
+ AVFilterBufferRef *overpicref;
+
+ int max_plane_step[4]; ///< steps per pixel for each plane
+ int hsub, vsub; ///< chroma subsampling values
+
+ char x_expr[256], y_expr[256];
+} OverlayContext;
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+ OverlayContext *over = ctx->priv;
+
+ av_strlcpy(over->x_expr, "0", sizeof(over->x_expr));
+ av_strlcpy(over->y_expr, "0", sizeof(over->y_expr));
+
+ if (args)
+ sscanf(args, "%255[^:]:%255[^:]", over->x_expr, over->y_expr);
+
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ OverlayContext *over = ctx->priv;
+
+ if (over->overpicref)
+ avfilter_unref_buffer(over->overpicref);
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ const enum PixelFormat inout_pix_fmts[] = { PIX_FMT_YUV420P, PIX_FMT_NONE };
+ const enum PixelFormat blend_pix_fmts[] = { PIX_FMT_YUVA420P, PIX_FMT_NONE };
+ AVFilterFormats *inout_formats = avfilter_make_format_list(inout_pix_fmts);
+ AVFilterFormats *blend_formats = avfilter_make_format_list(blend_pix_fmts);
+
+ avfilter_formats_ref(inout_formats, &ctx->inputs [MAIN ]->out_formats);
+ avfilter_formats_ref(blend_formats, &ctx->inputs [OVERLAY]->out_formats);
+ avfilter_formats_ref(inout_formats, &ctx->outputs[MAIN ]->in_formats );
+
+ return 0;
+}
+
+static int config_input_main(AVFilterLink *inlink)
+{
+ OverlayContext *over = inlink->dst->priv;
+ const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
+
+ av_image_fill_max_pixsteps(over->max_plane_step, NULL, pix_desc);
+ over->hsub = pix_desc->log2_chroma_w;
+ over->vsub = pix_desc->log2_chroma_h;
+
+ return 0;
+}
+
+static int config_input_overlay(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ OverlayContext *over = inlink->dst->priv;
+ char *expr;
+ double var_values[VAR_VARS_NB], res;
+ int ret;
+
+ /* Finish the configuration by evaluating the expressions
+ now when both inputs are configured. */
+ var_values[VAR_E ] = M_E;
+ var_values[VAR_PHI] = M_PHI;
+ var_values[VAR_PI ] = M_PI;
+
+ var_values[VAR_MAIN_W ] = var_values[VAR_MW] = ctx->inputs[MAIN ]->w;
+ var_values[VAR_MAIN_H ] = var_values[VAR_MH] = ctx->inputs[MAIN ]->h;
+ var_values[VAR_OVERLAY_W] = var_values[VAR_OW] = ctx->inputs[OVERLAY]->w;
+ var_values[VAR_OVERLAY_H] = var_values[VAR_OH] = ctx->inputs[OVERLAY]->h;
+
+ if ((ret = av_expr_parse_and_eval(&res, (expr = over->x_expr), var_names, var_values,
+ NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
+ goto fail;
+ over->x = res;
+ if ((ret = av_expr_parse_and_eval(&res, (expr = over->y_expr), var_names, var_values,
+ NULL, NULL, NULL, NULL, NULL, 0, ctx)))
+ goto fail;
+ over->y = res;
+ /* x may depend on y */
+ if ((ret = av_expr_parse_and_eval(&res, (expr = over->x_expr), var_names, var_values,
+ NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
+ goto fail;
+ over->x = res;
+
+ av_log(ctx, AV_LOG_INFO,
+ "main w:%d h:%d fmt:%s overlay x:%d y:%d w:%d h:%d fmt:%s\n",
+ ctx->inputs[MAIN]->w, ctx->inputs[MAIN]->h,
+ av_pix_fmt_descriptors[ctx->inputs[MAIN]->format].name,
+ over->x, over->y,
+ ctx->inputs[OVERLAY]->w, ctx->inputs[OVERLAY]->h,
+ av_pix_fmt_descriptors[ctx->inputs[OVERLAY]->format].name);
+
+ if (over->x < 0 || over->y < 0 ||
+ over->x + var_values[VAR_OVERLAY_W] > var_values[VAR_MAIN_W] ||
+ over->y + var_values[VAR_OVERLAY_H] > var_values[VAR_MAIN_H]) {
+ av_log(ctx, AV_LOG_ERROR,
+ "Overlay area (%d,%d)<->(%d,%d) not within the main area (0,0)<->(%d,%d) or zero-sized\n",
+ over->x, over->y,
+ (int)(over->x + var_values[VAR_OVERLAY_W]),
+ (int)(over->y + var_values[VAR_OVERLAY_H]),
+ (int)var_values[VAR_MAIN_W], (int)var_values[VAR_MAIN_H]);
+ return AVERROR(EINVAL);
+ }
+ return 0;
+
+fail:
+ av_log(NULL, AV_LOG_ERROR,
+ "Error when evaluating the expression '%s'\n", expr);
+ return ret;
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ int exact;
+ // common timebase computation:
+ AVRational tb1 = ctx->inputs[MAIN ]->time_base;
+ AVRational tb2 = ctx->inputs[OVERLAY]->time_base;
+ AVRational *tb = &ctx->outputs[0]->time_base;
+ exact = av_reduce(&tb->num, &tb->den,
+ av_gcd((int64_t)tb1.num * tb2.den,
+ (int64_t)tb2.num * tb1.den),
+ (int64_t)tb1.den * tb2.den, INT_MAX);
+ av_log(ctx, AV_LOG_INFO,
+ "main_tb:%d/%d overlay_tb:%d/%d -> tb:%d/%d exact:%d\n",
+ tb1.num, tb1.den, tb2.num, tb2.den, tb->num, tb->den, exact);
+ if (!exact)
+ av_log(ctx, AV_LOG_WARNING,
+ "Timestamp conversion inexact, timestamp information loss may occurr\n");
+
+ outlink->w = ctx->inputs[MAIN]->w;
+ outlink->h = ctx->inputs[MAIN]->h;
+
+ return 0;
+}
+
+static AVFilterBufferRef *get_video_buffer(AVFilterLink *link, int perms, int w, int h)
+{
+ return avfilter_get_video_buffer(link->dst->outputs[0], perms, w, h);
+}
+
+static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
+{
+ AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0);
+
+ inlink->dst->outputs[0]->out_buf = outpicref;
+
+ avfilter_start_frame(inlink->dst->outputs[0], outpicref);
+}
+
+static void start_frame_overlay(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
+{
+ AVFilterContext *ctx = inlink->dst;
+ OverlayContext *over = ctx->priv;
+
+ over->overpicref = inpicref;
+ over->overpicref->pts = av_rescale_q(inpicref->pts, ctx->inputs[OVERLAY]->time_base,
+ ctx->outputs[0]->time_base);
+}
+
+static void blend_slice(AVFilterContext *ctx,
+ AVFilterBufferRef *dst, AVFilterBufferRef *src,
+ int x, int y, int w, int h,
+ int slice_y, int slice_w, int slice_h)
+{
+ OverlayContext *over = ctx->priv;
+ int i, j, k;
+ int width, height;
+ int overlay_end_y = y+h;
+ int slice_end_y = slice_y+slice_h;
+ int end_y, start_y;
+
+ width = FFMIN(slice_w - x, w);
+ end_y = FFMIN(slice_end_y, overlay_end_y);
+ start_y = FFMAX(y, slice_y);
+ height = end_y - start_y;
+
+ if (dst->format == PIX_FMT_BGR24 || dst->format == PIX_FMT_RGB24) {
+ uint8_t *dp = dst->data[0] + x * 3 + start_y * dst->linesize[0];
+ uint8_t *sp = src->data[0];
+ int b = dst->format == PIX_FMT_BGR24 ? 2 : 0;
+ int r = dst->format == PIX_FMT_BGR24 ? 0 : 2;
+ if (slice_y > y)
+ sp += (slice_y - y) * src->linesize[0];
+ for (i = 0; i < height; i++) {
+ uint8_t *d = dp, *s = sp;
+ for (j = 0; j < width; j++) {
+ d[r] = (d[r] * (0xff - s[3]) + s[0] * s[3] + 128) >> 8;
+ d[1] = (d[1] * (0xff - s[3]) + s[1] * s[3] + 128) >> 8;
+ d[b] = (d[b] * (0xff - s[3]) + s[2] * s[3] + 128) >> 8;
+ d += 3;
+ s += 4;
+ }
+ dp += dst->linesize[0];
+ sp += src->linesize[0];
+ }
+ } else {
+ for (i = 0; i < 3; i++) {
+ int hsub = i ? over->hsub : 0;
+ int vsub = i ? over->vsub : 0;
+ uint8_t *dp = dst->data[i] + (x >> hsub) +
+ (start_y >> vsub) * dst->linesize[i];
+ uint8_t *sp = src->data[i];
+ uint8_t *ap = src->data[3];
+ int wp = FFALIGN(width, 1<<hsub) >> hsub;
+ int hp = FFALIGN(height, 1<<vsub) >> vsub;
+ if (slice_y > y) {
+ sp += ((slice_y - y) >> vsub) * src->linesize[i];
+ ap += (slice_y - y) * src->linesize[3];
+ }
+ for (j = 0; j < hp; j++) {
+ uint8_t *d = dp, *s = sp, *a = ap;
+ for (k = 0; k < wp; k++) {
+ // average alpha for color components, improve quality
+ int alpha_v, alpha_h, alpha;
+ if (hsub && vsub && j+1 < hp && k+1 < wp) {
+ alpha = (a[0] + a[src->linesize[3]] +
+ a[1] + a[src->linesize[3]+1]) >> 2;
+ } else if (hsub || vsub) {
+ alpha_h = hsub && k+1 < wp ?
+ (a[0] + a[1]) >> 1 : a[0];
+ alpha_v = vsub && j+1 < hp ?
+ (a[0] + a[src->linesize[3]]) >> 1 : a[0];
+ alpha = (alpha_v + alpha_h) >> 1;
+ } else
+ alpha = a[0];
+ *d = (*d * (0xff - alpha) + *s++ * alpha + 128) >> 8;
+ d++;
+ a += 1 << hsub;
+ }
+ dp += dst->linesize[i];
+ sp += src->linesize[i];
+ ap += (1 << vsub) * src->linesize[3];
+ }
+ }
+ }
+}
+
+static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AVFilterLink *outlink = ctx->outputs[0];
+ AVFilterBufferRef *outpicref = outlink->out_buf;
+ OverlayContext *over = ctx->priv;
+
+ outpicref->pts = av_rescale_q(outpicref->pts, ctx->inputs[MAIN]->time_base,
+ outlink->time_base);
+
+ if (!over->overpicref || over->overpicref->pts < outpicref->pts) {
+ AVFilterBufferRef *old = over->overpicref;
+ over->overpicref = NULL;
+ avfilter_request_frame(ctx->inputs[OVERLAY]);
+ if (over->overpicref) {
+ if (old) avfilter_unref_buffer(old);
+ } else
+ over->overpicref = old;
+ }
+ if (over->overpicref &&
+ !(over->x >= outpicref->video->w || over->y >= outpicref->video->h ||
+ y+h < over->y || y >= over->y + over->overpicref->video->h)) {
+ blend_slice(ctx, outpicref, over->overpicref, over->x, over->y,
+ over->overpicref->video->w, over->overpicref->video->h,
+ y, outpicref->video->w, h);
+ }
+ avfilter_draw_slice(outlink, y, h, slice_dir);
+}
+
+static void end_frame(AVFilterLink *inlink)
+{
+ avfilter_end_frame(inlink->dst->outputs[0]);
+ avfilter_unref_buffer(inlink->cur_buf);
+}
+
+static void null_draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir) { }
+
+static void null_end_frame(AVFilterLink *inlink) { }
+
+AVFilter avfilter_vf_overlay = {
+ .name = "overlay",
+ .description = NULL_IF_CONFIG_SMALL("Overlay a video source on top of the input."),
+
+ .init = init,
+ .uninit = uninit,
+
+ .priv_size = sizeof(OverlayContext),
+
+ .query_formats = query_formats,
+
+ .inputs = (AVFilterPad[]) {{ .name = "main",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .start_frame = start_frame,
+ .get_video_buffer= get_video_buffer,
+ .config_props = config_input_main,
+ .draw_slice = draw_slice,
+ .end_frame = end_frame,
+ .min_perms = AV_PERM_READ,
+ .rej_perms = AV_PERM_REUSE2, },
+ { .name = "overlay",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .start_frame = start_frame_overlay,
+ .config_props = config_input_overlay,
+ .draw_slice = null_draw_slice,
+ .end_frame = null_end_frame,
+ .min_perms = AV_PERM_READ,
+ .rej_perms = AV_PERM_REUSE2, },
+ { .name = NULL}},
+ .outputs = (AVFilterPad[]) {{ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_output, },
+ { .name = NULL}},
+};
--
1.7.1
--ReaqsoxgOBHFXBhH--
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