[FFmpeg-cvslog] lavfi: add libass based subtitles renderer
Stefano Sabatini
git at videolan.org
Sat Nov 26 10:46:20 CET 2011
ffmpeg | branch: master | Stefano Sabatini <stefasab at gmail.com> | Sat Sep 17 15:52:19 2011 +0200| [28338bc2a3bb316cde2dfc308722c3cdc3d7b046] | committer: Stefano Sabatini
lavfi: add libass based subtitles renderer
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=28338bc2a3bb316cde2dfc308722c3cdc3d7b046
---
Changelog | 1 +
configure | 5 +
doc/filters.texi | 16 +++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/avfilter.h | 4 +-
libavfilter/vf_ass.c | 242 ++++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 268 insertions(+), 2 deletions(-)
diff --git a/Changelog b/Changelog
index b781f33..69ed8cc 100644
--- a/Changelog
+++ b/Changelog
@@ -124,6 +124,7 @@ easier to use. The changes are:
- compact and csv output in ffprobe
- pan audio filter
- IFF Amiga Continuous Bitmap (ACBM) decoder
+- ass filter
version 0.8:
diff --git a/configure b/configure
index dccf63c..3c47043 100755
--- a/configure
+++ b/configure
@@ -168,6 +168,7 @@ External library support:
--enable-frei0r enable frei0r video filtering
--enable-gnutls enable gnutls [no]
--enable-libaacplus enable AAC+ encoding via libaacplus [no]
+ --enable-libass enable libass subtitles rendering [no]
--enable-libcelt enable CELT decoding via libcelt [no]
--enable-libopencore-amrnb enable AMR-NB de/encoding via libopencore-amrnb [no]
--enable-libopencore-amrwb enable AMR-WB decoding via libopencore-amrwb [no]
@@ -1008,6 +1009,7 @@ CONFIG_LIST="
hardcoded_tables
huffman
libaacplus
+ libass
libcdio
libcelt
libdc1394
@@ -1613,6 +1615,7 @@ udp_protocol_deps="network"
# filters
amovie_filter_deps="avcodec avformat"
+ass_filter_deps="libass"
blackframe_filter_deps="gpl"
boxblur_filter_deps="gpl"
cropdetect_filter_deps="gpl"
@@ -3057,6 +3060,7 @@ enabled avisynth && require2 vfw32 "windows.h vfw.h" AVIFileInit -lavifil32
enabled frei0r && { check_header frei0r.h || die "ERROR: frei0r.h header not found"; }
enabled gnutls && require_pkg_config gnutls gnutls/gnutls.h gnutls_global_init
enabled libaacplus && require "libaacplus >= 2.0.0" aacplus.h aacplusEncOpen -laacplus
+enabled libass && require_pkg_config libass ass/ass.h ass_library_init
enabled libcelt && require libcelt celt/celt.h celt_decode -lcelt0
enabled libdc1394 && require_pkg_config libdc1394-2 dc1394/dc1394.h dc1394_new
enabled libdirac && require_pkg_config dirac \
@@ -3395,6 +3399,7 @@ echo "AVISynth enabled ${avisynth-no}"
echo "frei0r enabled ${frei0r-no}"
echo "gnutls enabled ${gnutls-no}"
echo "libaacplus enabled ${libaacplus-no}"
+echo "libass enabled ${libass-no}"
echo "libcdio support ${libcdio-no}"
echo "libcelt enabled ${libcelt-no}"
echo "libdc1394 support ${libdc1394-no}"
diff --git a/doc/filters.texi b/doc/filters.texi
index cefb8ad..38856e5 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -574,6 +574,22 @@ build.
Below is a description of the currently available video filters.
+ at section ass
+
+Draw ASS (Advanced Substation Alpha) subtitles on top of input video
+using the libass library.
+
+To enable compilation of this filter you need to configure FFmpeg with
+ at code{--enable-libass}.
+
+This filter accepts in input the name of the ass file to render.
+
+For example, to render the file @file{sub.ass} on top of the input
+video, use the command:
+ at example
+ass=sub.ass
+ at end example
+
@section blackframe
Detect frames that are (almost) completely black. Can be useful to
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index cab6f2e..27979a3 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -40,6 +40,7 @@ OBJS-$(CONFIG_ANULLSRC_FILTER) += asrc_anullsrc.o
OBJS-$(CONFIG_ABUFFERSINK_FILTER) += sink_buffer.o
OBJS-$(CONFIG_ANULLSINK_FILTER) += asink_anullsink.o
+OBJS-$(CONFIG_ASS_FILTER) += vf_ass.o
OBJS-$(CONFIG_BLACKFRAME_FILTER) += vf_blackframe.o
OBJS-$(CONFIG_BOXBLUR_FILTER) += vf_boxblur.o
OBJS-$(CONFIG_COPY_FILTER) += vf_copy.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index c4b6972..176cfa6 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -51,6 +51,7 @@ void avfilter_register_all(void)
REGISTER_FILTER (ABUFFERSINK, abuffersink, asink);
REGISTER_FILTER (ANULLSINK, anullsink, asink);
+ REGISTER_FILTER (ASS, ass, vf);
REGISTER_FILTER (BLACKFRAME, blackframe, vf);
REGISTER_FILTER (BOXBLUR, boxblur, vf);
REGISTER_FILTER (COPY, copy, vf);
diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index d3afc35..6b0724d 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -29,8 +29,8 @@
#include "libavutil/rational.h"
#define LIBAVFILTER_VERSION_MAJOR 2
-#define LIBAVFILTER_VERSION_MINOR 49
-#define LIBAVFILTER_VERSION_MICRO 1
+#define LIBAVFILTER_VERSION_MINOR 50
+#define LIBAVFILTER_VERSION_MICRO 0
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
LIBAVFILTER_VERSION_MINOR, \
diff --git a/libavfilter/vf_ass.c b/libavfilter/vf_ass.c
new file mode 100644
index 0000000..7ef78f1
--- /dev/null
+++ b/libavfilter/vf_ass.c
@@ -0,0 +1,242 @@
+/*
+ * Copyright (c) 2011 Baptiste Coudurier
+ * Copyright (c) 2011 Stefano Sabatini
+ *
+ * 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
+ * Libass subtitles burning filter.
+ *
+ * @see{http://www.matroska.org/technical/specs/subtitles/ssa.html}
+ */
+
+#include <ass/ass.h>
+
+#include "libavutil/avstring.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/pixdesc.h"
+#include "drawutils.h"
+#include "avfilter.h"
+
+typedef struct {
+ ASS_Library *library;
+ ASS_Renderer *renderer;
+ ASS_Track *track;
+ int hsub, vsub;
+ char *filename;
+ uint8_t rgba_map[4];
+ int pix_step[4]; ///< steps per pixel for each plane of the main output
+} AssContext;
+
+/* libass supports a log level ranging from 0 to 7 */
+int ass_libav_log_level_map[] = {
+ AV_LOG_QUIET, /* 0 */
+ AV_LOG_PANIC, /* 1 */
+ AV_LOG_FATAL, /* 2 */
+ AV_LOG_ERROR, /* 3 */
+ AV_LOG_WARNING, /* 4 */
+ AV_LOG_INFO, /* 5 */
+ AV_LOG_VERBOSE, /* 6 */
+ AV_LOG_DEBUG, /* 7 */
+};
+
+static void ass_log(int ass_level, const char *fmt, va_list args, void *ctx)
+{
+ int level = ass_libav_log_level_map[ass_level];
+
+ av_vlog(ctx, level, fmt, args);
+ av_log(ctx, level, "\n");
+}
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+ AssContext *ass = ctx->priv;
+
+ if (args)
+ ass->filename = av_get_token(&args, ":");
+ if (!ass->filename || !*ass->filename) {
+ av_log(ctx, AV_LOG_ERROR, "No filename provided!\n");
+ return AVERROR(EINVAL);
+ }
+
+ ass->library = ass_library_init();
+ if (!ass->library) {
+ av_log(ctx, AV_LOG_ERROR, "Could not initialize libass.\n");
+ return AVERROR(EINVAL);
+ }
+ ass_set_message_cb(ass->library, ass_log, ctx);
+
+ ass->renderer = ass_renderer_init(ass->library);
+ if (!ass->renderer) {
+ av_log(ctx, AV_LOG_ERROR, "Could not initialize libass renderer.\n");
+ return AVERROR(EINVAL);
+ }
+
+ ass->track = ass_read_file(ass->library, ass->filename, NULL);
+ if (!ass->track) {
+ av_log(ctx, AV_LOG_ERROR,
+ "Could not create a libass track when reading file '%s'\n",
+ ass->filename);
+ return AVERROR(EINVAL);
+ }
+
+ ass_set_fonts(ass->renderer, NULL, NULL, 1, NULL, 1);
+
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ AssContext *ass = ctx->priv;
+
+ av_freep(&ass->filename);
+ if (ass->track)
+ ass_free_track(ass->track);
+ if (ass->renderer)
+ ass_renderer_done(ass->renderer);
+ if (ass->library)
+ ass_library_done(ass->library);
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum PixelFormat pix_fmts[] = {
+ PIX_FMT_ARGB, PIX_FMT_RGBA,
+ PIX_FMT_ABGR, PIX_FMT_BGRA,
+ PIX_FMT_RGB24, PIX_FMT_BGR24,
+ PIX_FMT_NONE
+ };
+
+ avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
+
+ return 0;
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+ AssContext *ass = inlink->dst->priv;
+ const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
+ double sar = inlink->sample_aspect_ratio.num ?
+ av_q2d(inlink->sample_aspect_ratio) : 1;
+ double dar = inlink->w / inlink->h * sar;
+
+ av_image_fill_max_pixsteps(ass->pix_step, NULL, pix_desc);
+ ff_fill_rgba_map(ass->rgba_map, inlink->format);
+
+ ass->hsub = pix_desc->log2_chroma_w;
+ ass->vsub = pix_desc->log2_chroma_h;
+
+ ass_set_frame_size (ass->renderer, inlink->w, inlink->h);
+ ass_set_aspect_ratio(ass->renderer, dar, sar);
+
+ return 0;
+}
+
+static void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }
+
+#define R 0
+#define G 1
+#define B 2
+#define A 3
+
+#define SET_PIXEL_RGB(picref, rgba_color, val, x, y, pixel_step, r_off, g_off, b_off) { \
+ p = picref->data[0] + (x) * pixel_step + ((y) * picref->linesize[0]); \
+ alpha = rgba_color[A] * (val) * 129; \
+ *(p+r_off) = (alpha * rgba_color[R] + (255*255*129 - alpha) * *(p+r_off)) >> 23; \
+ *(p+g_off) = (alpha * rgba_color[G] + (255*255*129 - alpha) * *(p+g_off)) >> 23; \
+ *(p+b_off) = (alpha * rgba_color[B] + (255*255*129 - alpha) * *(p+b_off)) >> 23; \
+}
+
+/* libass stores an RGBA color in the format RRGGBBTT, where TT is the transparency level */
+#define AR(c) ( (c)>>24)
+#define AG(c) (((c)>>16)&0xFF)
+#define AB(c) (((c)>>8) &0xFF)
+#define AA(c) ((0xFF-c) &0xFF)
+
+static void overlay_ass_image(AVFilterBufferRef *picref, const uint8_t *rgba_map, const int pix_step,
+ const ASS_Image *image)
+{
+ int i, j;
+ int alpha;
+ uint8_t *p;
+ const int ro = rgba_map[R];
+ const int go = rgba_map[G];
+ const int bo = rgba_map[B];
+
+ for (; image; image = image->next) {
+ uint8_t rgba_color[] = {AR(image->color), AG(image->color), AB(image->color), AA(image->color)};
+ unsigned char *row = image->bitmap;
+
+ for (i = 0; i < image->h; i++) {
+ for (j = 0; j < image->w; j++) {
+ if (row[j]) {
+ SET_PIXEL_RGB(picref, rgba_color, row[j], image->dst_x + j, image->dst_y + i, pix_step, ro, go, bo);
+ }
+ }
+ row += image->stride;
+ }
+ }
+}
+
+static void end_frame(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AVFilterLink *outlink = ctx->outputs[0];
+ AssContext *ass = ctx->priv;
+ AVFilterBufferRef *picref = inlink->cur_buf;
+ int detect_change = 0;
+ double time_ms = picref->pts * av_q2d(inlink->time_base) * 1000;
+ ASS_Image *image = ass_render_frame(ass->renderer, ass->track,
+ time_ms, &detect_change);
+
+ if (detect_change)
+ av_log(ctx, AV_LOG_DEBUG, "Change happened at time ms:%f\n", time_ms);
+
+ overlay_ass_image(picref, ass->rgba_map, ass->pix_step[0], image);
+
+ avfilter_draw_slice(outlink, 0, picref->video->h, 1);
+ avfilter_end_frame(outlink);
+}
+
+AVFilter avfilter_vf_ass = {
+ .name = "ass",
+ .description = NULL_IF_CONFIG_SMALL("Render subtitles onto input video using the libass library."),
+ .priv_size = sizeof(AssContext),
+ .init = init,
+ .uninit = uninit,
+ .query_formats = query_formats,
+
+ .inputs = (const AVFilterPad[]) {
+ { .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .get_video_buffer = avfilter_null_get_video_buffer,
+ .start_frame = avfilter_null_start_frame,
+ .draw_slice = null_draw_slice,
+ .end_frame = end_frame,
+ .config_props = config_input,
+ .min_perms = AV_PERM_WRITE | AV_PERM_READ,
+ .rej_perms = AV_PERM_PRESERVE },
+ { .name = NULL}
+ },
+ .outputs = (const AVFilterPad[]) {
+ { .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO, },
+ { .name = NULL}
+ },
+};
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