/* * SSA/ASS demuxer * Copyright (c) 2008 Michael Niedermayer * Copyright (c) 2014 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 */ #include <stdint.h> #include "avformat.h" #include "internal.h" #include "subtitles.h" #include "libavcodec/internal.h" #include "libavutil/bprint.h" typedef struct ASSContext { FFDemuxSubtitlesQueue q; unsigned readorder; } ASSContext; static int ass_probe(AVProbeData *p) { char buf[13]; FFTextReader tr; ff_text_init_buf(&tr, p->buf, p->buf_size); ff_text_read(&tr, buf, sizeof(buf)); if (!memcmp(buf, "[Script Info]", 13)) return AVPROBE_SCORE_MAX; return 0; } static int ass_read_close(AVFormatContext *s) { ASSContext *ass = s->priv_data; ff_subtitles_queue_clean(&ass->q); return 0; } static int read_dialogue(ASSContext *ass, AVBPrint *dst, const uint8_t *p, int64_t *start, int *duration) { int pos = 0; int64_t end; int hh1, mm1, ss1, ms1; int hh2, mm2, ss2, ms2; if (sscanf(p, "Dialogue: %*[^,],%d:%d:%d%*c%d,%d:%d:%d%*c%d,%n", &hh1, &mm1, &ss1, &ms1, &hh2, &mm2, &ss2, &ms2, &pos) >= 8 && pos > 0) { /* This is not part of the sscanf itself in order to handle an actual * number (which would be the Layer) or the form "Marked=N" (which is * the old SSA field, now replaced by Layer, and will lead to Layer * being 0 here). */ const int layer = atoi(p + 10); end = (hh2*3600LL + mm2*60LL + ss2) * 100LL + ms2; *start = (hh1*3600LL + mm1*60LL + ss1) * 100LL + ms1; *duration = end - *start; av_bprint_clear(dst); av_bprintf(dst, "%u,%d,%s", ass->readorder++, layer, p + pos); /* right strip the buffer */ while (dst->len > 0 && dst->str[dst->len - 1] == '\r' || dst->str[dst->len - 1] == '\n') dst->str[--dst->len] = 0; return 0; } return -1; } static int64_t get_line(AVBPrint *buf, FFTextReader *tr) { int64_t pos = ff_text_pos(tr); av_bprint_clear(buf); for (;;) { char c = ff_text_r8(tr); if (!c) break; av_bprint_chars(buf, c, 1); if (c == '\n') break; } return pos; } static int ass_read_header(AVFormatContext *s) { ASSContext *ass = s->priv_data; AVBPrint header, line, rline; int res = 0; AVStream *st; FFTextReader tr; ff_text_init_avio(&tr, s->pb); st = avformat_new_stream(s, NULL); if (!st) return AVERROR(ENOMEM); avpriv_set_pts_info(st, 64, 1, 100); st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; st->codec->codec_id = AV_CODEC_ID_ASS; av_bprint_init(&header, 0, AV_BPRINT_SIZE_UNLIMITED); av_bprint_init(&line, 0, AV_BPRINT_SIZE_UNLIMITED); av_bprint_init(&rline, 0, AV_BPRINT_SIZE_UNLIMITED); for (;;) { int64_t pos = get_line(&line, &tr); int64_t ts_start = AV_NOPTS_VALUE; int duration = -1; AVPacket *sub; if (!line.str[0]) // EOF break; if (read_dialogue(ass, &rline, line.str, &ts_start, &duration) < 0) { av_bprintf(&header, "%s", line.str); continue; } sub = ff_subtitles_queue_insert(&ass->q, rline.str, rline.len, 0); if (!sub) { res = AVERROR(ENOMEM); goto end; } sub->pos = pos; sub->pts = ts_start; sub->duration = duration; } res = avpriv_bprint_to_extradata(st->codec, &header); if (res < 0) goto end; ff_subtitles_queue_finalize(&ass->q); end: av_bprint_finalize(&header, NULL); av_bprint_finalize(&line, NULL); av_bprint_finalize(&rline, NULL); return res; } static int ass_read_packet(AVFormatContext *s, AVPacket *pkt) { ASSContext *ass = s->priv_data; return ff_subtitles_queue_read_packet(&ass->q, pkt); } static int ass_read_seek(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags) { ASSContext *ass = s->priv_data; return ff_subtitles_queue_seek(&ass->q, s, stream_index, min_ts, ts, max_ts, flags); } AVInputFormat ff_ass_demuxer = { .name = "ass", .long_name = NULL_IF_CONFIG_SMALL("SSA (SubStation Alpha) subtitle"), .priv_data_size = sizeof(ASSContext), .read_probe = ass_probe, .read_header = ass_read_header, .read_packet = ass_read_packet, .read_close = ass_read_close, .read_seek2 = ass_read_seek, };