TOOLS/avisubdump.c

   1 /*
   2  * avisubdump
   3  *
   4  * avi vobsub subtitle stream dumper (c) 2004 Tobias Diedrich
   5  * Licensed under GNU GPLv2 or (at your option) any later version.
   6  *
   7  * The subtitles are dumped to stdout.
   8  */
   9
  10 #define _LARGEFILE_SOURCE
  11 #define _FILE_OFFSET_BITS 64
  12 #include <unistd.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <fcntl.h>
  17 #include <errno.h>
  18
  19 #define FCC(a,b,c,d)  (((a))|((b)<<8)|((c)<<16)|((d)<<24))
  20
  21 #define FCC_RIFF FCC('R','I','F','F')
  22 #define FCC_LIST FCC('L','I','S','T')
  23 #define FCC_strh FCC('s','t','r','h')
  24 #define FCC_txts FCC('t','x','t','s')
  25 #define FCC_GAB2 FCC('G','A','B','2')
  26
  27 #define GAB_LANGUAGE            0
  28 #define GAB_ENTRY               1
  29 #define GAB_LANGUAGE_UNICODE    2
  30 #define GAB_ENTRY_UNICODE       3
  31 #define GAB_RAWTEXTSUBTITLE     4
  32
  33 static unsigned int getle16(FILE* f){
  34         unsigned int res;
  35
  36         res  = fgetc(f);
  37         res |= fgetc(f) << 8;
  38
  39         return res;
  40 }
  41
  42 static unsigned int getle(FILE* f){
  43         unsigned int res;
  44
  45         res  = fgetc(f);
  46         res |= fgetc(f) << 8;
  47         res |= fgetc(f) << 16;
  48         res |= fgetc(f) << 24;
  49
  50         return res;
  51 }
  52
  53 static void skip(FILE *f, int len)
  54 {
  55         if (f != stdin) {
  56                 fseek(f,len,SEEK_CUR);
  57         } else {
  58                 void *buf = malloc(len);
  59                 fread(buf,len,1,f);
  60                 free(buf);
  61         }
  62 }
  63
  64 static int stream_id(unsigned int id)
  65 {
  66         char c1,c2;
  67         c1 = (char)(id & 0xff);
  68         c2 = (char)((id >> 8) & 0xff);
  69         if (c1 >= '0' && c1 <= '9' &&
  70             c2 >= '0' && c2 <= '9') {
  71                 c1 -= '0';
  72                 c2 -= '0';
  73                 return c1*10+c2;
  74         }
  75         return -1;
  76 }
  77
  78 static int dumpsub_gab2(FILE *f, int size) {
  79         int ret = 0;
  80
  81         while (ret + 6 <= size) {
  82                 unsigned int len, id;
  83                 char *buf;
  84                 int i;
  85
  86                 id = getle16(f); ret += 2;
  87                 len = getle(f); ret += 4;
  88                 if (ret + len > size) break;
  89
  90                 buf = malloc(len);
  91                 ret += fread(buf, 1, len, f);
  92
  93                 switch (id) {
  94                 case GAB_LANGUAGE_UNICODE: /* FIXME: convert to utf-8; endianness */
  95                         for (i=0; i<len; i++) buf[i] = buf[i*2];
  96                 case GAB_LANGUAGE:
  97                         fprintf(stderr, "LANGUAGE: %s\n", buf);
  98                         break;
  99                 case GAB_ENTRY_UNICODE: /* FIXME: convert to utf-8; endianness */
 100                         for (i=0; i<len; i++) buf[i] = buf[i*2];
 101                 case GAB_ENTRY:
 102                         fprintf(stderr, "ENTRY: %s\n", buf);
 103                         break;
 104                 case GAB_RAWTEXTSUBTITLE:
 105                         printf("%s", buf);
 106                         break;
 107                 default:
 108                         fprintf(stderr, "Unknown type %d, len %d\n", id, len);
 109                         break;
 110                 }
 111                 free(buf);
 112         }
 113
 114         return ret;
 115 }
 116
 117 static void dump(FILE *f) {
 118         unsigned int id, len;
 119         int stream = 0;
 120         int substream = -2;
 121
 122         while (1) {
 123                 id = getle(f);
 124                 len = getle(f);
 125
 126                 if(feof(f)) break;
 127
 128                 if (id == FCC_RIFF ||
 129                     id == FCC_LIST) {
 130                         getle(f);
 131                         continue;
 132                 } else if (id == FCC_strh) {
 133                         id = getle(f); len -= 4;
 134                         fprintf(stderr, "Stream %d is %c%c%c%c",
 135                                stream,
 136                                id,
 137                                id >> 8,
 138                                id >> 16,
 139                                id >> 24);
 140                         if (id == FCC_txts) {
 141                                 substream = stream;
 142                                 fprintf(stderr, " (subtitle stream)");
 143                         }
 144                         fprintf(stderr, ".\n");
 145                         stream++;
 146                 } else if (stream_id(id) == substream) {
 147                         unsigned int subid;
 148                         subid = getle(f); len -= 4;
 149                         if (subid != FCC_GAB2) {
 150                                 fprintf(stderr,
 151                                         "Unknown subtitle chunk %c%c%c%c (%08x).\n",
 152                                         id, id >> 8, id >> 16, id >> 24, subid);
 153                         } else {
 154                                 skip(f,1); len -= 1;
 155                                 len -= dumpsub_gab2(f, len);
 156                         }
 157                 }
 158                 len+=len&1;
 159                 skip(f,len);
 160         }
 161 }
 162
 163 int main(int argc,char* argv[])
 164 {
 165         FILE* f;
 166
 167         if (argc != 2) {
 168                 fprintf(stderr, "Usage: %s <avi>\n", argv[0]);
 169                 exit(1);
 170         }
 171
 172         if (strcmp(argv[argc-1], "-") == 0) f=stdin;
 173         else f=fopen(argv[argc-1],"rb");
 174
 175         if (!f) {
 176                 fprintf(stderr, "Could not open '%s': %s\n",
 177                         argv[argc-1], strerror(errno));
 178                 exit(-errno);
 179         }
 180
 181         dump(f);
 182
 183         return 0;
 184 }
 185