/***************************************************************************** * subsdec.c : text subtitles decoder ***************************************************************************** * Copyright (C) 2000-2006 the VideoLAN team * $Id$ * * Authors: Gildas Bazin * Samuel Hocevar * Derk-Jan Hartman * Bernie Purcell * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ /***************************************************************************** * Preamble *****************************************************************************/ #ifdef HAVE_CONFIG_H # include "config.h" #endif #include "subsdec.h" #include /***************************************************************************** * Local prototypes *****************************************************************************/ static int OpenDecoder ( vlc_object_t * ); static void CloseDecoder ( vlc_object_t * ); static subpicture_t *DecodeBlock ( decoder_t *, block_t ** ); static subpicture_t *ParseText ( decoder_t *, block_t * ); static char *StripTags ( char * ); static char *CreateHtmlSubtitle ( char * ); /***************************************************************************** * Module descriptor. *****************************************************************************/ static const char *const ppsz_encodings[] = { DEFAULT_NAME, "ASCII", "UTF-8", "", "ISO-8859-1", "CP1252", "MacRoman", "MacIceland","ISO-8859-15", "", "ISO-8859-2", "CP1250", "MacCentralEurope", "MacCroatian", "MacRomania", "", "ISO-8859-5", "CP1251", "MacCyrillic", "MacUkraine", "KOI8-R", "KOI8-U", "KOI8-RU", "", "ISO-8859-6", "CP1256", "MacArabic", "", "ISO-8859-7", "CP1253", "MacGreek", "", "ISO-8859-8", "CP1255", "MacHebrew", "", "ISO-8859-9", "CP1254", "MacTurkish", "", "ISO-8859-13", "CP1257", "", "ISO-2022-JP", "ISO-2022-JP-1", "ISO-2022-JP-2", "EUC-JP", "SHIFT_JIS", "", "ISO-2022-CN", "ISO-2022-CN-EXT", "EUC-CN", "EUC-TW", "BIG5", "BIG5-HKSCS", "", "ISO-2022-KR", "EUC-KR", "", "MacThai", "KOI8-T", "", "ISO-8859-3", "ISO-8859-4", "ISO-8859-10", "ISO-8859-14", "ISO-8859-16", "", "CP850", "CP862", "CP866", "CP874", "CP932", "CP949", "CP950", "CP1133", "CP1258", "", "Macintosh", "", "UTF-7", "UTF-16", "UTF-16BE", "UTF-16LE", "UTF-32", "UTF-32BE", "UTF-32LE", "C99", "JAVA", "UCS-2", "UCS-2BE", "UCS-2LE", "UCS-4", "UCS-4BE", "UCS-4LE", "", "HZ", "GBK", "GB18030", "JOHAB", "ARMSCII-8", "Georgian-Academy", "Georgian-PS", "TIS-620", "MuleLao-1", "VISCII", "TCVN", "HPROMAN8", "NEXTSTEP" }; /* SSA supports charset selection. The following known charsets are used: 0 = Ansi - Western European 1 = default 2 = symbol 3 = invalid 77 = Mac 128 = Japanese (Shift JIS) 129 = Hangul 130 = Johab 134 = GB2312 Simplified Chinese 136 = Big5 Traditional Chinese 161 = Greek 162 = Turkish 163 = Vietnamese 177 = Hebrew 178 = Arabic 186 = Baltic 204 = Russian (Cyrillic) 222 = Thai 238 = Eastern European 254 = PC 437 */ static const int pi_justification[] = { 0, 1, 2 }; static const char *const ppsz_justification_text[] = { N_("Center"),N_("Left"),N_("Right")}; #define ENCODING_TEXT N_("Subtitles text encoding") #define ENCODING_LONGTEXT N_("Set the encoding used in text subtitles") #define ALIGN_TEXT N_("Subtitles justification") #define ALIGN_LONGTEXT N_("Set the justification of subtitles") #define AUTODETECT_UTF8_TEXT N_("UTF-8 subtitles autodetection") #define AUTODETECT_UTF8_LONGTEXT N_("This enables automatic detection of " \ "UTF-8 encoding within subtitles files.") #define FORMAT_TEXT N_("Formatted Subtitles") #define FORMAT_LONGTEXT N_("Some subtitle formats allow for text formatting. " \ "VLC partly implements this, but you can choose to disable all formatting.") vlc_module_begin(); set_shortname( N_("Subtitles")); set_description( N_("Text subtitles decoder") ); set_capability( "decoder", 50 ); set_callbacks( OpenDecoder, CloseDecoder ); set_category( CAT_INPUT ); set_subcategory( SUBCAT_INPUT_SCODEC ); add_integer( "subsdec-align", 0, NULL, ALIGN_TEXT, ALIGN_LONGTEXT, false ); change_integer_list( pi_justification, ppsz_justification_text, 0 ); add_string( "subsdec-encoding", DEFAULT_NAME, NULL, ENCODING_TEXT, ENCODING_LONGTEXT, false ); change_string_list( ppsz_encodings, 0, 0 ); add_bool( "subsdec-autodetect-utf8", true, NULL, AUTODETECT_UTF8_TEXT, AUTODETECT_UTF8_LONGTEXT, false ); add_bool( "subsdec-formatted", true, NULL, FORMAT_TEXT, FORMAT_LONGTEXT, false ); vlc_module_end(); /***************************************************************************** * OpenDecoder: probe the decoder and return score ***************************************************************************** * Tries to launch a decoder and return score so that the interface is able * to chose. *****************************************************************************/ static int OpenDecoder( vlc_object_t *p_this ) { decoder_t *p_dec = (decoder_t*)p_this; decoder_sys_t *p_sys; vlc_value_t val; switch( p_dec->fmt_in.i_codec ) { case VLC_FOURCC('s','u','b','t'): case VLC_FOURCC('s','s','a',' '): case VLC_FOURCC('t','1','4','0'): break; default: return VLC_EGENERIC; } p_dec->pf_decode_sub = DecodeBlock; /* Allocate the memory needed to store the decoder's structure */ p_dec->p_sys = p_sys = malloc( sizeof( *p_sys ) ); if( p_sys == NULL ) return VLC_ENOMEM; /* init of p_sys */ memset( p_sys, 0, sizeof( *p_sys ) ); p_sys->i_align = 0; p_sys->iconv_handle = (vlc_iconv_t)-1; p_sys->b_autodetect_utf8 = false; p_sys->b_ass = false; p_sys->i_original_height = -1; p_sys->i_original_width = -1; TAB_INIT( p_sys->i_ssa_styles, p_sys->pp_ssa_styles ); TAB_INIT( p_sys->i_images, p_sys->pp_images ); char *psz_charset = NULL; /* First try demux-specified encoding */ if( p_dec->fmt_in.i_codec == VLC_FOURCC('t','1','4','0') ) psz_charset = strdup( "UTF-8" ); /* IUT T.140 is always using UTF-8 */ else if( p_dec->fmt_in.subs.psz_encoding && *p_dec->fmt_in.subs.psz_encoding ) { psz_charset = strdup (p_dec->fmt_in.subs.psz_encoding); msg_Dbg (p_dec, "trying demuxer-specified character encoding: %s", p_dec->fmt_in.subs.psz_encoding ?: "not specified"); } /* Second, try configured encoding */ if (psz_charset == NULL) { psz_charset = var_CreateGetNonEmptyString (p_dec, "subsdec-encoding"); if ((psz_charset != NULL) && !strcasecmp (psz_charset, DEFAULT_NAME)) { free (psz_charset); psz_charset = NULL; } msg_Dbg (p_dec, "trying configured character encoding: %s", psz_charset ?: "not specified"); } /* Third, try "local" encoding with optional UTF-8 autodetection */ if (psz_charset == NULL) { psz_charset = strdup (GetFallbackEncoding ()); msg_Dbg (p_dec, "trying default character encoding: %s", psz_charset ?: "not specified"); if (var_CreateGetBool (p_dec, "subsdec-autodetect-utf8")) { msg_Dbg (p_dec, "using automatic UTF-8 detection"); p_sys->b_autodetect_utf8 = true; } } /* Forth, don't do character decoding, i.e. assume UTF-8 */ if (psz_charset == NULL) { psz_charset = strdup ("UTF-8"); msg_Dbg (p_dec, "using UTF-8 character encoding" ); } if ((psz_charset != NULL) && strcasecmp (psz_charset, "UTF-8") && strcasecmp (psz_charset, "utf8")) { p_sys->iconv_handle = vlc_iconv_open ("UTF-8", psz_charset); if (p_sys->iconv_handle == (vlc_iconv_t)(-1)) msg_Err (p_dec, "cannot convert from %s: %m", psz_charset); } free (psz_charset); var_Create( p_dec, "subsdec-align", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT ); var_Get( p_dec, "subsdec-align", &val ); p_sys->i_align = val.i_int; if( p_dec->fmt_in.i_codec == VLC_FOURCC('s','s','a',' ') && var_CreateGetBool( p_dec, "subsdec-formatted" ) ) { if( p_dec->fmt_in.i_extra > 0 ) ParseSSAHeader( p_dec ); } return VLC_SUCCESS; } /**************************************************************************** * DecodeBlock: the whole thing **************************************************************************** * This function must be fed with complete subtitles units. ****************************************************************************/ static subpicture_t *DecodeBlock( decoder_t *p_dec, block_t **pp_block ) { subpicture_t *p_spu = NULL; if( !pp_block || *pp_block == NULL ) return NULL; p_spu = ParseText( p_dec, *pp_block ); block_Release( *pp_block ); *pp_block = NULL; return p_spu; } /***************************************************************************** * CloseDecoder: clean up the decoder *****************************************************************************/ static void CloseDecoder( vlc_object_t *p_this ) { decoder_t *p_dec = (decoder_t *)p_this; decoder_sys_t *p_sys = p_dec->p_sys; if( p_sys->iconv_handle != (vlc_iconv_t)-1 ) vlc_iconv_close( p_sys->iconv_handle ); if( p_sys->pp_ssa_styles ) { int i; for( i = 0; i < p_sys->i_ssa_styles; i++ ) { if( !p_sys->pp_ssa_styles[i] ) continue; free( p_sys->pp_ssa_styles[i]->psz_stylename ); free( p_sys->pp_ssa_styles[i]->font_style.psz_fontname ); free( p_sys->pp_ssa_styles[i] ); } TAB_CLEAN( p_sys->i_ssa_styles, p_sys->pp_ssa_styles ); } if( p_sys->pp_images ) { int i; for( i = 0; i < p_sys->i_images; i++ ) { if( !p_sys->pp_images[i] ) continue; if( p_sys->pp_images[i]->p_pic ) picture_Release( p_sys->pp_images[i]->p_pic ); free( p_sys->pp_images[i]->psz_filename ); free( p_sys->pp_images[i] ); } TAB_CLEAN( p_sys->i_images, p_sys->pp_images ); } free( p_sys ); } /***************************************************************************** * ParseText: parse an text subtitle packet and send it to the video output *****************************************************************************/ static subpicture_t *ParseText( decoder_t *p_dec, block_t *p_block ) { decoder_sys_t *p_sys = p_dec->p_sys; subpicture_t *p_spu = NULL; char *psz_subtitle = NULL; video_format_t fmt; /* We cannot display a subpicture with no date */ if( p_block->i_pts == 0 ) { msg_Warn( p_dec, "subtitle without a date" ); return NULL; } /* Check validity of packet data */ /* An "empty" line containing only \0 can be used to force and ephemer picture from the screen */ if( p_block->i_buffer < 1 ) { msg_Warn( p_dec, "no subtitle data" ); return NULL; } /* Should be resiliant against bad subtitles */ psz_subtitle = strndup( (const char *)p_block->p_buffer, p_block->i_buffer ); if( psz_subtitle == NULL ) return NULL; if( p_sys->iconv_handle == (vlc_iconv_t)-1 ) { if (EnsureUTF8( psz_subtitle ) == NULL) { msg_Err( p_dec, _("failed to convert subtitle encoding.\n" "Try manually setting a character-encoding " "before you open the file.") ); } } else { if( p_sys->b_autodetect_utf8 ) { if( IsUTF8( psz_subtitle ) == NULL ) { msg_Dbg( p_dec, "invalid UTF-8 sequence: " "disabling UTF-8 subtitles autodetection" ); p_sys->b_autodetect_utf8 = false; } } if( !p_sys->b_autodetect_utf8 ) { size_t inbytes_left = strlen( psz_subtitle ); size_t outbytes_left = 6 * inbytes_left; char *psz_new_subtitle = malloc( outbytes_left + 1 ); char *psz_convert_buffer_out = psz_new_subtitle; const char *psz_convert_buffer_in = psz_subtitle; size_t ret = vlc_iconv( p_sys->iconv_handle, &psz_convert_buffer_in, &inbytes_left, &psz_convert_buffer_out, &outbytes_left ); *psz_convert_buffer_out++ = '\0'; free( psz_subtitle ); if( ( ret == (size_t)(-1) ) || inbytes_left ) { free( psz_new_subtitle ); msg_Err( p_dec, _("failed to convert subtitle encoding.\n" "Try manually setting a character-encoding " "before you open the file.") ); return NULL; } psz_subtitle = realloc( psz_new_subtitle, psz_convert_buffer_out - psz_new_subtitle ); } } /* Create the subpicture unit */ p_spu = p_dec->pf_spu_buffer_new( p_dec ); if( !p_spu ) { msg_Warn( p_dec, "can't get spu buffer" ); free( psz_subtitle ); return NULL; } p_spu->b_pausable = true; /* Create a new subpicture region */ memset( &fmt, 0, sizeof(video_format_t) ); fmt.i_chroma = VLC_FOURCC('T','E','X','T'); fmt.i_aspect = 0; fmt.i_width = fmt.i_height = 0; fmt.i_x_offset = fmt.i_y_offset = 0; p_spu->p_region = p_spu->pf_create_region( VLC_OBJECT(p_dec), &fmt ); if( !p_spu->p_region ) { msg_Err( p_dec, "cannot allocate SPU region" ); free( psz_subtitle ); p_dec->pf_spu_buffer_del( p_dec, p_spu ); return NULL; } /* Decode and format the subpicture unit */ if( p_dec->fmt_in.i_codec != VLC_FOURCC('s','s','a',' ') ) { /* Normal text subs, easy markup */ p_spu->p_region->i_align = SUBPICTURE_ALIGN_BOTTOM | p_sys->i_align; p_spu->i_x = p_sys->i_align ? 20 : 0; p_spu->i_y = 10; /* Remove formatting from string */ p_spu->p_region->psz_text = StripTags( psz_subtitle ); if( var_CreateGetBool( p_dec, "subsdec-formatted" ) ) { p_spu->p_region->psz_html = CreateHtmlSubtitle( psz_subtitle ); } p_spu->i_start = p_block->i_pts; p_spu->i_stop = p_block->i_pts + p_block->i_length; p_spu->b_ephemer = (p_block->i_length == 0); p_spu->b_absolute = false; } else { /* Decode SSA/USF strings */ if( p_dec->fmt_in.i_codec == VLC_FOURCC('s','s','a',' ') ) ParseSSAString( p_dec, psz_subtitle, p_spu ); p_spu->i_start = p_block->i_pts; p_spu->i_stop = p_block->i_pts + p_block->i_length; p_spu->b_ephemer = (p_block->i_length == 0); p_spu->b_absolute = false; p_spu->i_original_picture_width = p_sys->i_original_width; p_spu->i_original_picture_height = p_sys->i_original_height; } free( psz_subtitle ); return p_spu; } char* GotoNextLine( char *psz_text ) { char *p_newline = psz_text; while( p_newline[0] != '\0' ) { if( p_newline[0] == '\n' || p_newline[0] == '\r' ) { p_newline++; while( p_newline[0] == '\n' || p_newline[0] == '\r' ) p_newline++; break; } else p_newline++; } return p_newline; } /* Function now handles tags with attribute values, and tries * to deal with &' commands too. It no longer modifies the string * in place, so that the original text can be reused */ static char *StripTags( char *psz_subtitle ) { char *psz_text_start; char *psz_text; psz_text = psz_text_start = malloc( strlen( psz_subtitle ) + 1 ); if( !psz_text_start ) return NULL; while( *psz_subtitle ) { if( *psz_subtitle == '<' ) { if( strncasecmp( psz_subtitle, "
", 5 ) == 0 ) *psz_text++ = '\n'; psz_subtitle += strcspn( psz_subtitle, ">" ); } else if( *psz_subtitle == '&' ) { if( !strncasecmp( psz_subtitle, "<", 4 )) { *psz_text++ = '<'; psz_subtitle += strcspn( psz_subtitle, ";" ); } else if( !strncasecmp( psz_subtitle, ">", 4 )) { *psz_text++ = '>'; psz_subtitle += strcspn( psz_subtitle, ";" ); } else if( !strncasecmp( psz_subtitle, "&", 5 )) { *psz_text++ = '&'; psz_subtitle += strcspn( psz_subtitle, ";" ); } else if( !strncasecmp( psz_subtitle, """, 6 )) { *psz_text++ = '\"'; psz_subtitle += strcspn( psz_subtitle, ";" ); } else { /* Assume it is just a normal ampersand */ *psz_text++ = '&'; } } else { *psz_text++ = *psz_subtitle; } psz_subtitle++; } *psz_text = '\0'; psz_text_start = realloc( psz_text_start, strlen( psz_text_start ) + 1 ); return psz_text_start; } /* Try to respect any style tags present in the subtitle string. The main * problem here is a lack of adequate specs for the subtitle formats. * SSA/ASS and USF are both detail spec'ed -- but they are handled elsewhere. * SAMI has a detailed spec, but extensive rework is needed in the demux * code to prevent all this style information being excised, as it presently * does. * That leaves the others - none of which were (I guess) originally intended * to be carrying style information. Over time people have used them that way. * In the absence of specifications from which to work, the tags supported * have been restricted to the simple set permitted by the USF DTD, ie. : * Basic:
, , , * Extended: * Attributes: face * family * size * color * outline-color * shadow-color * outline-level * shadow-level * back-color * alpha * There is also the further restriction that the subtitle be well-formed * as an XML entity, ie. the HTML sentence: * Bold and Italics * doesn't qualify because the tags aren't nested one inside the other. * tags are automatically added to the output to ensure * well-formedness. * If the text doesn't qualify for any reason, a NULL string is * returned, and the rendering engine will fall back to the * plain text version of the subtitle. */ static char *CreateHtmlSubtitle( char *psz_subtitle ) { char *psz_tag = malloc( ( strlen( psz_subtitle ) / 3 ) + 1 ); if( !psz_tag ) return NULL; size_t i_buf_size = strlen( psz_subtitle ) + 100; char *psz_html_start = malloc( i_buf_size ); psz_tag[ 0 ] = '\0'; if( psz_html_start == NULL ) { free( psz_tag ); return NULL; } char *psz_html = psz_html_start; strcpy( psz_html, "" ); psz_html += 6; while( *psz_subtitle ) { if( *psz_subtitle == '\n' ) { strcpy( psz_html, "
" ); psz_html += 5; psz_subtitle++; } else if( *psz_subtitle == '<' ) { if( !strncasecmp( psz_subtitle, "
", 5 )) { strcpy( psz_html, "
" ); psz_html += 5; psz_subtitle += 5; } else if( !strncasecmp( psz_subtitle, "", 3 ) ) { strcpy( psz_html, "" ); strcat( psz_tag, "b" ); psz_html += 3; psz_subtitle += 3; } else if( !strncasecmp( psz_subtitle, "", 3 ) ) { strcpy( psz_html, "" ); strcat( psz_tag, "i" ); psz_html += 3; psz_subtitle += 3; } else if( !strncasecmp( psz_subtitle, "", 3 ) ) { strcpy( psz_html, "" ); strcat( psz_tag, "u" ); psz_html += 3; psz_subtitle += 3; } else if( !strncasecmp( psz_subtitle, "= 0 ) { psz_lastTag = psz_tag + i_len; i_len = 0; switch( *psz_lastTag ) { case 'b': b_match = !strncasecmp( psz_subtitle, "", 4 ); i_len = 4; break; case 'i': b_match = !strncasecmp( psz_subtitle, "", 4 ); i_len = 4; break; case 'u': b_match = !strncasecmp( psz_subtitle, "", 4 ); i_len = 4; break; case 'f': b_match = !strncasecmp( psz_subtitle, "", 7 ); i_len = 7; break; } } if( ! b_match ) { /* Not well formed -- kill everything */ free( psz_html_start ); psz_html_start = NULL; break; } *psz_lastTag = '\0'; strncpy( psz_html, psz_subtitle, i_len ); psz_html += i_len; psz_subtitle += i_len; } else { psz_subtitle += strcspn( psz_subtitle, ">" ); } } else if( *psz_subtitle == '&' ) { if( !strncasecmp( psz_subtitle, "<", 4 )) { strcpy( psz_html, "<" ); psz_html += 4; psz_subtitle += 4; } else if( !strncasecmp( psz_subtitle, ">", 4 )) { strcpy( psz_html, ">" ); psz_html += 4; psz_subtitle += 4; } else if( !strncasecmp( psz_subtitle, "&", 5 )) { strcpy( psz_html, "&" ); psz_html += 5; psz_subtitle += 5; } else { strcpy( psz_html, "&" ); psz_html += 5; psz_subtitle++; } } else { *psz_html = *psz_subtitle; if( psz_html > psz_html_start ) { /* Check for double whitespace */ if((( *psz_html == ' ' ) || ( *psz_html == '\t' )) && (( *(psz_html-1) == ' ' ) || ( *(psz_html-1) == '\t' ))) { strcpy( psz_html, NO_BREAKING_SPACE ); psz_html += strlen( NO_BREAKING_SPACE ) - 1; } } psz_html++; psz_subtitle++; } if( ( size_t )( psz_html - psz_html_start ) > i_buf_size - 10 ) { int i_len = psz_html - psz_html_start; i_buf_size += 100; psz_html_start = realloc( psz_html_start, i_buf_size ); psz_html = psz_html_start + i_len; *psz_html = '\0'; } } strcpy( psz_html, "" ); psz_html += 7; if( psz_tag[ 0 ] != '\0' ) { /* Not well formed -- kill everything */ free( psz_html_start ); psz_html_start = NULL; } else if( psz_html_start ) { /* Shrink the memory requirements */ psz_html_start = realloc( psz_html_start, psz_html - psz_html_start + 1 ); } free( psz_tag ); return psz_html_start; }