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Diffstat (limited to 'libavfilter/vf_ass.c')
-rw-r--r-- | libavfilter/vf_ass.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/libavfilter/vf_ass.c b/libavfilter/vf_ass.c new file mode 100644 index 0000000..6b20631 --- /dev/null +++ b/libavfilter/vf_ass.c @@ -0,0 +1,227 @@ +/* + * 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/opt.h" +#include "libavutil/parseutils.h" +#include "drawutils.h" +#include "avfilter.h" +#include "internal.h" +#include "formats.h" +#include "video.h" + +typedef struct { + const AVClass *class; + ASS_Library *library; + ASS_Renderer *renderer; + ASS_Track *track; + char *filename; + uint8_t rgba_map[4]; + int pix_step[4]; ///< steps per pixel for each plane of the main output + int original_w, original_h; + FFDrawContext draw; +} AssContext; + +#define OFFSET(x) offsetof(AssContext, x) +#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM + +static const AVOption ass_options[] = { + {"original_size", "set the size of the original video (used to scale fonts)", OFFSET(original_w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS }, + {NULL}, +}; + +AVFILTER_DEFINE_CLASS(ass); + +/* libass supports a log level ranging from 0 to 7 */ +static const int ass_libavfilter_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_libavfilter_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) +{ + AssContext *ass = ctx->priv; + int ret; + + ass->class = &ass_class; + av_opt_set_defaults(ass); + + 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); + } + + if (*args++ == ':' && (ret = av_set_options_string(ass, args, "=", ":")) < 0) + return ret; + + 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) +{ + ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0)); + return 0; +} + +static int config_input(AVFilterLink *inlink) +{ + AssContext *ass = inlink->dst->priv; + + ff_draw_init(&ass->draw, inlink->format, 0); + + ass_set_frame_size (ass->renderer, inlink->w, inlink->h); + if (ass->original_w && ass->original_h) + ass_set_aspect_ratio(ass->renderer, (double)inlink->w / inlink->h, + (double)ass->original_w / ass->original_h); + + return 0; +} + +static int null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { return 0; } + +/* 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(AssContext *ass, AVFilterBufferRef *picref, + const ASS_Image *image) +{ + for (; image; image = image->next) { + uint8_t rgba_color[] = {AR(image->color), AG(image->color), AB(image->color), AA(image->color)}; + FFDrawColor color; + ff_draw_color(&ass->draw, &color, rgba_color); + ff_blend_mask(&ass->draw, &color, + picref->data, picref->linesize, + picref->video->w, picref->video->h, + image->bitmap, image->stride, image->w, image->h, + 3, 0, image->dst_x, image->dst_y); + } +} + +static int 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(ass, picref, image); + + ff_draw_slice(outlink, 0, picref->video->h, 1); + return ff_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 = ff_null_get_video_buffer, + .start_frame = ff_null_start_frame, + .draw_slice = null_draw_slice, + .end_frame = end_frame, + .config_props = config_input, + .min_perms = AV_PERM_WRITE | AV_PERM_READ }, + { .name = NULL} + }, + .outputs = (const AVFilterPad[]) { + { .name = "default", + .type = AVMEDIA_TYPE_VIDEO, }, + { .name = NULL} + }, + .priv_class = &ass_class, +}; 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