/* * Copyright (c) 2011 Baptiste Coudurier * Copyright (c) 2011 Stefano Sabatini * Copyright (c) 2012 Clément Bœsch * * 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 #include "config.h" #if CONFIG_SUBTITLES_FILTER # include "libavcodec/avcodec.h" # include "libavformat/avformat.h" #endif #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; char *charenc; 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 #define COMMON_OPTIONS \ {"filename", "set the filename of file to read", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS }, \ {"f", "set the filename of file to read", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS }, \ {"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 }, \ /* 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) { AssContext *ass = ctx->priv; if (!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_set_fonts(ass->renderer, NULL, NULL, 1, NULL, 1); return 0; } static av_cold void uninit(AVFilterContext *ctx) { AssContext *ass = ctx->priv; 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; } /* 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, AVFrame *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->width, picref->height, image->bitmap, image->stride, image->w, image->h, 3, 0, image->dst_x, image->dst_y); } } static int filter_frame(AVFilterLink *inlink, AVFrame *picref) { AVFilterContext *ctx = inlink->dst; AVFilterLink *outlink = ctx->outputs[0]; AssContext *ass = ctx->priv; 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); return ff_filter_frame(outlink, picref); } static const AVFilterPad ass_inputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, .filter_frame = filter_frame, .config_props = config_input, .needs_writable = 1, }, { NULL } }; static const AVFilterPad ass_outputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, }, { NULL } }; #if CONFIG_ASS_FILTER static const AVOption ass_options[] = { COMMON_OPTIONS {NULL}, }; AVFILTER_DEFINE_CLASS(ass); static av_cold int init_ass(AVFilterContext *ctx) { AssContext *ass = ctx->priv; int ret = init(ctx); if (ret < 0) return ret; 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); } return 0; } AVFilter avfilter_vf_ass = { .name = "ass", .description = NULL_IF_CONFIG_SMALL("Render ASS subtitles onto input video using the libass library."), .priv_size = sizeof(AssContext), .init = init_ass, .uninit = uninit, .query_formats = query_formats, .inputs = ass_inputs, .outputs = ass_outputs, .priv_class = &ass_class, }; #endif #if CONFIG_SUBTITLES_FILTER static const AVOption subtitles_options[] = { COMMON_OPTIONS {"charenc", "set input character encoding", OFFSET(charenc), AV_OPT_TYPE_STRING, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS}, {NULL}, }; AVFILTER_DEFINE_CLASS(subtitles); static av_cold int init_subtitles(AVFilterContext *ctx) { int ret, sid; AVDictionary *codec_opts = NULL; AVFormatContext *fmt = NULL; AVCodecContext *dec_ctx = NULL; AVCodec *dec = NULL; const AVCodecDescriptor *dec_desc; AVStream *st; AVPacket pkt; AssContext *ass = ctx->priv; /* Init libass */ ret = init(ctx); if (ret < 0) return ret; ass->track = ass_new_track(ass->library); if (!ass->track) { av_log(ctx, AV_LOG_ERROR, "Could not create a libass track\n"); return AVERROR(EINVAL); } /* Open subtitles file */ ret = avformat_open_input(&fmt, ass->filename, NULL, NULL); if (ret < 0) { av_log(ctx, AV_LOG_ERROR, "Unable to open %s\n", ass->filename); goto end; } ret = avformat_find_stream_info(fmt, NULL); if (ret < 0) goto end; /* Locate subtitles stream */ ret = av_find_best_stream(fmt, AVMEDIA_TYPE_SUBTITLE, -1, -1, NULL, 0); if (ret < 0) { av_log(ctx, AV_LOG_ERROR, "Unable to locate subtitle stream in %s\n", ass->filename); goto end; } sid = ret; st = fmt->streams[sid]; /* Open decoder */ dec_ctx = st->codec; dec = avcodec_find_decoder(dec_ctx->codec_id); if (!dec) { av_log(ctx, AV_LOG_ERROR, "Failed to find subtitle codec %s\n", avcodec_get_name(dec_ctx->codec_id)); return AVERROR(EINVAL); } dec_desc = avcodec_descriptor_get(dec_ctx->codec_id); if (dec_desc && !(dec_desc->props & AV_CODEC_PROP_TEXT_SUB)) { av_log(ctx, AV_LOG_ERROR, "Only text based subtitles are currently supported\n"); return AVERROR_PATCHWELCOME; } if (ass->charenc) av_dict_set(&codec_opts, "sub_charenc", ass->charenc, 0); ret = avcodec_open2(dec_ctx, dec, &codec_opts); if (ret < 0) goto end; /* Decode subtitles and push them into the renderer (libass) */ if (dec_ctx->subtitle_header) ass_process_codec_private(ass->track, dec_ctx->subtitle_header, dec_ctx->subtitle_header_size); av_init_packet(&pkt); pkt.data = NULL; pkt.size = 0; while (av_read_frame(fmt, &pkt) >= 0) { int i, got_subtitle; AVSubtitle sub = {0}; if (pkt.stream_index == sid) { ret = avcodec_decode_subtitle2(dec_ctx, &sub, &got_subtitle, &pkt); if (ret < 0) { av_log(ctx, AV_LOG_WARNING, "Error decoding: %s (ignored)\n", av_err2str(ret)); } else if (got_subtitle) { for (i = 0; i < sub.num_rects; i++) { char *ass_line = sub.rects[i]->ass; if (!ass_line) break; ass_process_data(ass->track, ass_line, strlen(ass_line)); } } } av_free_packet(&pkt); avsubtitle_free(&sub); } end: av_dict_free(&codec_opts); if (dec_ctx) avcodec_close(dec_ctx); if (fmt) avformat_close_input(&fmt); return ret; } AVFilter avfilter_vf_subtitles = { .name = "subtitles", .description = NULL_IF_CONFIG_SMALL("Render text subtitles onto input video using the libass library."), .priv_size = sizeof(AssContext), .init = init_subtitles, .uninit = uninit, .query_formats = query_formats, .inputs = ass_inputs, .outputs = ass_outputs, .priv_class = &subtitles_class, }; #endif