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/** 22 * @file 23 * SAMI subtitle demuxer 24 * @see http://msdn.microsoft.com/en-us/library/ms971327.aspx 25 */ 26 27#include "avformat.h" 28#include "internal.h" 29#include "subtitles.h" 30#include "libavcodec/internal.h" 31#include "libavutil/avstring.h" 32#include "libavutil/bprint.h" 33#include "libavutil/intreadwrite.h" 34 35typedef struct { 36 FFDemuxSubtitlesQueue q; 37} SAMIContext; 38 39static int sami_probe(AVProbeData *p) 40{ 41 const unsigned char *ptr = p->buf; 42 43 if (AV_RB24(ptr) == 0xEFBBBF) 44 ptr += 3; /* skip UTF-8 BOM */ 45 return !strncmp(ptr, "<SAMI>", 6) ? AVPROBE_SCORE_MAX : 0; 46} 47 48static int sami_read_header(AVFormatContext *s) 49{ 50 SAMIContext *sami = s->priv_data; 51 AVStream *st = avformat_new_stream(s, NULL); 52 AVBPrint buf, hdr_buf; 53 char c = 0; 54 int res = 0, got_first_sync_point = 0; 55 56 if (!st) 57 return AVERROR(ENOMEM); 58 avpriv_set_pts_info(st, 64, 1, 1000); 59 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; 60 st->codec->codec_id = AV_CODEC_ID_SAMI; 61 62 av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED); 63 av_bprint_init(&hdr_buf, 0, AV_BPRINT_SIZE_UNLIMITED); 64 65 while (!url_feof(s->pb)) { 66 AVPacket *sub; 67 const int64_t pos = avio_tell(s->pb) - (c != 0); 68 int is_sync, n = ff_smil_extract_next_chunk(s->pb, &buf, &c); 69 70 if (n == 0) 71 break; 72 73 is_sync = !av_strncasecmp(buf.str, "<SYNC", 5); 74 if (is_sync) 75 got_first_sync_point = 1; 76 77 if (!got_first_sync_point) { 78 av_bprintf(&hdr_buf, "%s", buf.str); 79 } else { 80 sub = ff_subtitles_queue_insert(&sami->q, buf.str, buf.len, !is_sync); 81 if (!sub) { 82 res = AVERROR(ENOMEM); 83 goto end; 84 } 85 if (is_sync) { 86 const char *p = ff_smil_get_attr_ptr(buf.str, "Start"); 87 sub->pos = pos; 88 sub->pts = p ? strtol(p, NULL, 10) : 0; 89 sub->duration = -1; 90 } 91 } 92 av_bprint_clear(&buf); 93 } 94 95 res = avpriv_bprint_to_extradata(st->codec, &hdr_buf); 96 if (res < 0) 97 goto end; 98 99 ff_subtitles_queue_finalize(&sami->q); 100 101end: 102 av_bprint_finalize(&buf, NULL); 103 return res; 104} 105 106static int sami_read_packet(AVFormatContext *s, AVPacket *pkt) 107{ 108 SAMIContext *sami = s->priv_data; 109 return ff_subtitles_queue_read_packet(&sami->q, pkt); 110} 111 112static int sami_read_seek(AVFormatContext *s, int stream_index, 113 int64_t min_ts, int64_t ts, int64_t max_ts, int flags) 114{ 115 SAMIContext *sami = s->priv_data; 116 return ff_subtitles_queue_seek(&sami->q, s, stream_index, 117 min_ts, ts, max_ts, flags); 118} 119 120static int sami_read_close(AVFormatContext *s) 121{ 122 SAMIContext *sami = s->priv_data; 123 ff_subtitles_queue_clean(&sami->q); 124 return 0; 125} 126 127AVInputFormat ff_sami_demuxer = { 128 .name = "sami", 129 .long_name = NULL_IF_CONFIG_SMALL("SAMI subtitle format"), 130 .priv_data_size = sizeof(SAMIContext), 131 .read_probe = sami_probe, 132 .read_header = sami_read_header, 133 .read_packet = sami_read_packet, 134 .read_seek2 = sami_read_seek, 135 .read_close = sami_read_close, 136 .extensions = "smi,sami", 137}; 138