1/* 2 * Copyright (c) 2012 Clément Bœsch 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#include "codec_internal.h" 31#include "htmlsubtitles.h" 32 33typedef struct { 34 AVBPrint source; 35 AVBPrint content; 36 AVBPrint encoded_source; 37 AVBPrint encoded_content; 38 AVBPrint full; 39 int readorder; 40} SAMIContext; 41 42static int sami_paragraph_to_ass(AVCodecContext *avctx, const char *src) 43{ 44 SAMIContext *sami = avctx->priv_data; 45 int ret = 0; 46 char *tag = NULL; 47 char *dupsrc = av_strdup(src); 48 char *p = dupsrc; 49 AVBPrint *dst_content = &sami->encoded_content; 50 AVBPrint *dst_source = &sami->encoded_source; 51 52 if (!dupsrc) 53 return AVERROR(ENOMEM); 54 55 av_bprint_clear(&sami->encoded_content); 56 av_bprint_clear(&sami->content); 57 av_bprint_clear(&sami->encoded_source); 58 for (;;) { 59 char *saveptr = NULL; 60 int prev_chr_is_space = 0; 61 AVBPrint *dst = &sami->content; 62 63 /* parse & extract paragraph tag */ 64 p = av_stristr(p, "<P"); 65 if (!p) 66 break; 67 if (p[2] != '>' && !av_isspace(p[2])) { // avoid confusion with tags such as <PRE> 68 p++; 69 continue; 70 } 71 if (dst->len) // add a separator with the previous paragraph if there was one 72 av_bprintf(dst, "\\N"); 73 tag = av_strtok(p, ">", &saveptr); 74 if (!tag || !saveptr) 75 break; 76 p = saveptr; 77 78 /* check if the current paragraph is the "source" (speaker name) */ 79 if (av_stristr(tag, "ID=Source") || av_stristr(tag, "ID=\"Source\"")) { 80 dst = &sami->source; 81 av_bprint_clear(dst); 82 } 83 84 /* if empty event -> skip subtitle */ 85 while (av_isspace(*p)) 86 p++; 87 if (!strncmp(p, " ", 6)) { 88 ret = -1; 89 goto end; 90 } 91 92 /* extract the text, stripping most of the tags */ 93 while (*p) { 94 if (*p == '<') { 95 if (!av_strncasecmp(p, "<P", 2) && (p[2] == '>' || av_isspace(p[2]))) 96 break; 97 } 98 if (!av_strncasecmp(p, "<BR", 3)) { 99 av_bprintf(dst, "\\N"); 100 p++; 101 while (*p && *p != '>') 102 p++; 103 if (!*p) 104 break; 105 if (*p == '>') 106 p++; 107 continue; 108 } 109 if (!av_isspace(*p)) 110 av_bprint_chars(dst, *p, 1); 111 else if (!prev_chr_is_space) 112 av_bprint_chars(dst, ' ', 1); 113 prev_chr_is_space = av_isspace(*p); 114 p++; 115 } 116 } 117 118 av_bprint_clear(&sami->full); 119 if (sami->source.len) { 120 ret = ff_htmlmarkup_to_ass(avctx, dst_source, sami->source.str); 121 if (ret < 0) 122 goto end; 123 av_bprintf(&sami->full, "{\\i1}%s{\\i0}\\N", sami->encoded_source.str); 124 } 125 ret = ff_htmlmarkup_to_ass(avctx, dst_content, sami->content.str); 126 if (ret < 0) 127 goto end; 128 av_bprintf(&sami->full, "%s", sami->encoded_content.str); 129 130end: 131 av_free(dupsrc); 132 return ret; 133} 134 135static int sami_decode_frame(AVCodecContext *avctx, AVSubtitle *sub, 136 int *got_sub_ptr, const AVPacket *avpkt) 137{ 138 const char *ptr = avpkt->data; 139 SAMIContext *sami = avctx->priv_data; 140 141 if (ptr && avpkt->size > 0) { 142 int ret = sami_paragraph_to_ass(avctx, ptr); 143 if (ret < 0) 144 return ret; 145 // TODO: pass escaped sami->encoded_source.str as source 146 ret = ff_ass_add_rect(sub, sami->full.str, sami->readorder++, 0, NULL, NULL); 147 if (ret < 0) 148 return ret; 149 } 150 *got_sub_ptr = sub->num_rects > 0; 151 return avpkt->size; 152} 153 154static av_cold int sami_init(AVCodecContext *avctx) 155{ 156 SAMIContext *sami = avctx->priv_data; 157 av_bprint_init(&sami->source, 0, 2048); 158 av_bprint_init(&sami->content, 0, 2048); 159 av_bprint_init(&sami->encoded_source, 0, 2048); 160 av_bprint_init(&sami->encoded_content, 0, 2048); 161 av_bprint_init(&sami->full, 0, 2048); 162 return ff_ass_subtitle_header_default(avctx); 163} 164 165static av_cold int sami_close(AVCodecContext *avctx) 166{ 167 SAMIContext *sami = avctx->priv_data; 168 av_bprint_finalize(&sami->source, NULL); 169 av_bprint_finalize(&sami->content, NULL); 170 av_bprint_finalize(&sami->encoded_source, NULL); 171 av_bprint_finalize(&sami->encoded_content, NULL); 172 av_bprint_finalize(&sami->full, NULL); 173 return 0; 174} 175 176static void sami_flush(AVCodecContext *avctx) 177{ 178 SAMIContext *sami = avctx->priv_data; 179 if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP)) 180 sami->readorder = 0; 181} 182 183const FFCodec ff_sami_decoder = { 184 .p.name = "sami", 185 .p.long_name = NULL_IF_CONFIG_SMALL("SAMI subtitle"), 186 .p.type = AVMEDIA_TYPE_SUBTITLE, 187 .p.id = AV_CODEC_ID_SAMI, 188 .priv_data_size = sizeof(SAMIContext), 189 .init = sami_init, 190 .close = sami_close, 191 FF_CODEC_DECODE_SUB_CB(sami_decode_frame), 192 .flush = sami_flush, 193 .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE, 194}; 195