1/* 2 * Copyright (c) 2012 Cl��ment B��sch 3 * 4 * This file is part of FFmpeg. 5 * 6 * FFmpeg is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU Lesser General Public 8 * License as published by the Free Software Foundation; either 9 * version 2.1 of the License, or (at your option) any later version. 10 * 11 * FFmpeg is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 * Lesser General Public License for more details. 15 * 16 * You should have received a copy of the GNU Lesser General Public 17 * License along with FFmpeg; if not, write to the Free Software 18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 19 */ 20 21#ifndef AVFORMAT_SUBTITLES_H 22#define AVFORMAT_SUBTITLES_H 23 24#include <stdint.h> 25#include "avformat.h" 26#include "libavutil/bprint.h" 27 28enum sub_sort { 29 SUB_SORT_TS_POS = 0, ///< sort by timestamps, then position 30 SUB_SORT_POS_TS, ///< sort by position, then timestamps 31}; 32 33typedef struct { 34 AVPacket *subs; ///< array of subtitles packets 35 int nb_subs; ///< number of subtitles packets 36 int allocated_size; ///< allocated size for subs 37 int current_sub_idx; ///< current position for the read packet callback 38 enum sub_sort sort; ///< sort method to use when finalizing subtitles 39} FFDemuxSubtitlesQueue; 40 41/** 42 * Insert a new subtitle event. 43 * 44 * @param event the subtitle line, may not be zero terminated 45 * @param len the length of the event (in strlen() sense, so without '\0') 46 * @param merge set to 1 if the current event should be concatenated with the 47 * previous one instead of adding a new entry, 0 otherwise 48 */ 49AVPacket *ff_subtitles_queue_insert(FFDemuxSubtitlesQueue *q, 50 const uint8_t *event, int len, int merge); 51 52/** 53 * Set missing durations and sort subtitles by PTS, and then byte position. 54 */ 55void ff_subtitles_queue_finalize(FFDemuxSubtitlesQueue *q); 56 57/** 58 * Generic read_packet() callback for subtitles demuxers using this queue 59 * system. 60 */ 61int ff_subtitles_queue_read_packet(FFDemuxSubtitlesQueue *q, AVPacket *pkt); 62 63/** 64 * Update current_sub_idx to emulate a seek. Except the first parameter, it 65 * matches AVInputFormat->read_seek2 prototypes. 66 */ 67int ff_subtitles_queue_seek(FFDemuxSubtitlesQueue *q, AVFormatContext *s, int stream_index, 68 int64_t min_ts, int64_t ts, int64_t max_ts, int flags); 69 70/** 71 * Remove and destroy all the subtitles packets. 72 */ 73void ff_subtitles_queue_clean(FFDemuxSubtitlesQueue *q); 74 75/** 76 * SMIL helper to load next chunk ("<...>" or untagged content) in buf. 77 * 78 * @param c cached character, to avoid a backward seek 79 */ 80int ff_smil_extract_next_chunk(AVIOContext *pb, AVBPrint *buf, char *c); 81 82/** 83 * SMIL helper to point on the value of an attribute in the given tag. 84 * 85 * @param s SMIL tag ("<...>") 86 * @param attr the attribute to look for 87 */ 88const char *ff_smil_get_attr_ptr(const char *s, const char *attr); 89 90/** 91 * @brief Read a subtitles chunk. 92 * 93 * A chunk is defined by a multiline "event", ending with a second line break. 94 * The trailing line breaks are trimmed. CRLF are supported. 95 * Example: "foo\r\nbar\r\n\r\nnext" will print "foo\r\nbar" into buf, and pb 96 * will focus on the 'n' of the "next" string. 97 * 98 * @param pb I/O context 99 * @param buf an initialized buf where the chunk is written 100 * 101 * @note buf is cleared before writing into it. 102 */ 103void ff_subtitles_read_chunk(AVIOContext *pb, AVBPrint *buf); 104 105/** 106 * Get the number of characters to increment to jump to the next line, or to 107 * the end of the string. 108 * The function handles the following line breaks schemes: 109 * LF, CRLF (MS), or standalone CR (old MacOS). 110 */ 111static av_always_inline int ff_subtitles_next_line(const char *ptr) 112{ 113 int n = strcspn(ptr, "\r\n"); 114 ptr += n; 115 if (*ptr == '\r') { 116 ptr++; 117 n++; 118 } 119 if (*ptr == '\n') 120 n++; 121 return n; 122} 123 124#endif /* AVFORMAT_SUBTITLES_H */ 125