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 decoder 24 * @see http://msdn.microsoft.com/en-us/library/ms971327.aspx 25 */ 26 27#include "ass.h" 28#include "libavutil/avstring.h" 29#include "libavutil/bprint.h" 30 31typedef struct { 32 AVBPrint source; 33 AVBPrint content; 34 AVBPrint full; 35} SAMIContext; 36 37static int sami_paragraph_to_ass(AVCodecContext *avctx, const char *src) 38{ 39 SAMIContext *sami = avctx->priv_data; 40 int ret = 0; 41 char *tag = NULL; 42 char *dupsrc = av_strdup(src); 43 char *p = dupsrc; 44 45 av_bprint_clear(&sami->content); 46 for (;;) { 47 char *saveptr = NULL; 48 int prev_chr_is_space = 0; 49 AVBPrint *dst = &sami->content; 50 51 /* parse & extract paragraph tag */ 52 p = av_stristr(p, "<P"); 53 if (!p) 54 break; 55 if (p[2] != '>' && !av_isspace(p[2])) { // avoid confusion with tags such as <PRE> 56 p++; 57 continue; 58 } 59 if (dst->len) // add a separator with the previous paragraph if there was one 60 av_bprintf(dst, "\\N"); 61 tag = av_strtok(p, ">", &saveptr); 62 if (!tag || !saveptr) 63 break; 64 p = saveptr; 65 66 /* check if the current paragraph is the "source" (speaker name) */ 67 if (av_stristr(tag, "ID=Source") || av_stristr(tag, "ID=\"Source\"")) { 68 dst = &sami->source; 69 av_bprint_clear(dst); 70 } 71 72 /* if empty event -> skip subtitle */ 73 while (av_isspace(*p)) 74 p++; 75 if (!strncmp(p, " ", 6)) { 76 ret = -1; 77 goto end; 78 } 79 80 /* extract the text, stripping most of the tags */ 81 while (*p) { 82 if (*p == '<') { 83 if (!av_strncasecmp(p, "<P", 2) && (p[2] == '>' || av_isspace(p[2]))) 84 break; 85 if (!av_strncasecmp(p, "<BR", 3)) 86 av_bprintf(dst, "\\N"); 87 p++; 88 while (*p && *p != '>') 89 p++; 90 if (!*p) 91 break; 92 if (*p == '>') 93 p++; 94 } 95 if (!av_isspace(*p)) 96 av_bprint_chars(dst, *p, 1); 97 else if (!prev_chr_is_space) 98 av_bprint_chars(dst, ' ', 1); 99 prev_chr_is_space = av_isspace(*p); 100 p++; 101 } 102 } 103 104 av_bprint_clear(&sami->full); 105 if (sami->source.len) 106 av_bprintf(&sami->full, "{\\i1}%s{\\i0}\\N", sami->source.str); 107 av_bprintf(&sami->full, "%s\r\n", sami->content.str); 108 109end: 110 av_free(dupsrc); 111 return ret; 112} 113 114static int sami_decode_frame(AVCodecContext *avctx, 115 void *data, int *got_sub_ptr, AVPacket *avpkt) 116{ 117 AVSubtitle *sub = data; 118 const char *ptr = avpkt->data; 119 SAMIContext *sami = avctx->priv_data; 120 121 if (ptr && avpkt->size > 0 && !sami_paragraph_to_ass(avctx, ptr)) { 122 int ts_start = av_rescale_q(avpkt->pts, avctx->time_base, (AVRational){1,100}); 123 int ts_duration = avpkt->duration != -1 ? 124 av_rescale_q(avpkt->duration, avctx->time_base, (AVRational){1,100}) : -1; 125 ff_ass_add_rect(sub, sami->full.str, ts_start, ts_duration, 0); 126 } 127 *got_sub_ptr = sub->num_rects > 0; 128 return avpkt->size; 129} 130 131static av_cold int sami_init(AVCodecContext *avctx) 132{ 133 SAMIContext *sami = avctx->priv_data; 134 av_bprint_init(&sami->source, 0, 2048); 135 av_bprint_init(&sami->content, 0, 2048); 136 av_bprint_init(&sami->full, 0, 2048); 137 return ff_ass_subtitle_header_default(avctx); 138} 139 140static av_cold int sami_close(AVCodecContext *avctx) 141{ 142 SAMIContext *sami = avctx->priv_data; 143 av_bprint_finalize(&sami->source, NULL); 144 av_bprint_finalize(&sami->content, NULL); 145 av_bprint_finalize(&sami->full, NULL); 146 return 0; 147} 148 149AVCodec ff_sami_decoder = { 150 .name = "sami", 151 .long_name = NULL_IF_CONFIG_SMALL("SAMI subtitle"), 152 .type = AVMEDIA_TYPE_SUBTITLE, 153 .id = AV_CODEC_ID_SAMI, 154 .priv_data_size = sizeof(SAMIContext), 155 .init = sami_init, 156 .close = sami_close, 157 .decode = sami_decode_frame, 158}; 159