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