srtscroll.pl

   1 #!/usr/bin/env perl
   2 #
   3 # Copyright (c) 2009 Abel Abraham Camarillo Ojeda <acamari@the00z.org>
   4 #
   5 # Permission to use, copy, modify, and distribute this software for any
   6 # purpose with or without fee is hereby granted, provided that the above
   7 # copyright notice and this permission notice appear in all copies.
   8 #
   9 # THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10 # WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11 # MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12 # ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13 # WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14 # ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15 # OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16 #
  17 # srtscroll.pl: "scrolls" the time and ids of an srt file by some initial values
  18 #               it means: it adds to the time and id (of each entry) some values
  19
  20 # example:
  21 #
  22 #   cat file.srt | ./srtscroll '20' '01:02:03,800'
  23 #
  24 # scrolls  file.srt changing each id (adding to it '20') and adding to each
  25 # timestamp one hour, two minutes, three seconds and 800 milliseconds
  26 #
  27 # you can get timestamps in milliseconds in mplayer using:
  28 #
  29 # while sleep '.1'; do echo "get_time_pos"; done | mplayer -quiet -slave movie.avi
  30 #
  31 # or try using the x and z keys to delay the subs where you like them
  32
  33 # sets debug mode
  34 #my $debug = "yes";
  35
  36 # a doble line terminator delimits a paragraph (srt entry);
  37 # "\r\n" for DOS files, "\n" for everyone else files. (*.srt are commonly DOS
  38 # files)
  39 my $line_terminator = "\r\n";
  40
  41 # id scroll: we are going to add this value to the ids of all entries (can be
  42 # negative)
  43 my $id_scroll;
  44 $id_scroll = shift @ARGV;
  45
  46 # time scroll: we are going to add this value to the time of all entries (can be
  47 # negative)
  48 #
  49 # this value is specified in the form: hours:minutes:seconds,milliseconds
  50 # the value can have leading 0's (zeroes), if any they will be stripped on
  51 # before conversion.
  52 #
  53 # limits: hours         = 99
  54 #         minutes       = 59
  55 #         seconds       = 59
  56 #         milliseconds  = 999
  57 my $time_scroll;
  58 $time_scroll = shift @ARGV;
  59
  60 # read by "paragraphs"
  61 $/ = ($line_terminator x 2);
  62
  63 while (<>) {
  64 # gets the old srt entry
  65   my ($id, $time, @text);
  66
  67   ($id, $time, @text) = split $line_terminator;
  68
  69   my ($time_start, $time_end);
  70
  71   ($time_start, $time_end) = split /\s*-+>\s*/, $time;
  72
  73   if (debug("yes") eq "yes") {
  74   print '-', $id, $line_terminator,
  75         '-', $time, $line_terminator,
  76         '-', join ($line_terminator.'-', @text), ($line_terminator);
  77   }
  78 # gets the new srt entry
  79   my ($new_id, $new_time);
  80
  81   $new_id = $id + $id_scroll;
  82
  83   my ($new_time_start, $new_time_end);
  84
  85 # if the scroll is negative
  86   if ($time_scroll =~ /^-/) {
  87 # removes all minus signs
  88           my $t = join '', split '-', $time_scroll;
  89           $new_time_start = time_min($time_start, $t);
  90           $new_time_end   = time_min($time_end,   $t);
  91   } else {
  92           my $t = join '', split '-', $time_scroll;
  93           $new_time_start = time_add($time_start, $t);
  94           $new_time_end   = time_add($time_end,   $t);
  95   }
  96
  97   $new_time = $new_time_start . " --> " . $new_time_end;
  98
  99   print debug('+'), $new_id, $line_terminator,
 100         debug('+'), $new_time, $line_terminator,
 101         debug('+'), join ($line_terminator.debug('+'), @text),
 102                     ($line_terminator x 2);
 103
 104  #print "a + b: ",
 105  #      join(' ', time_fold(add_zeroes(time_add([qw(0 59 15 300)], [qw(1 1 1
 106  #                  1)])))) ,
 107  #      "\n";
 108 }
 109
 110 sub
 111 debug
 112 {
 113   if (wantarray) {
 114     return ($debug =~ /yes/i ? @_ : ());
 115   } else {
 116     return ($debug =~ /yes/i ? join('',@_) : undef);
 117   }
 118 }
 119
 120 # high level function...
 121 sub
 122 time_add
 123 {
 124   return time_fold(add_zeroes(_time_add(
 125                                 [rm_zeroes(time_unfold($_[0]))],
 126                                 [rm_zeroes(time_unfold($_[1]))])
 127                              ));
 128 }
 129
 130 sub
 131 time_min
 132 {
 133   return time_fold(add_zeroes(_time_min(
 134                                 [rm_zeroes(time_unfold($_[0]))],
 135                                 [rm_zeroes(time_unfold($_[1]))])
 136                              ));
 137 }
 138
 139 # removes the leading zeroes of a time array
 140 # example: rm_zeroes(time_unfold('00:00:00,000')) = (0,0,0,0)
 141 sub
 142 rm_zeroes
 143 {
 144   return map {s/^0+//g; $_} @_;
 145 }
 146
 147 # example: add_zeroes('0','2','3','99') = ('00','02','03','099')
 148 sub
 149 add_zeroes
 150 {
 151   my @tmp = @_;
 152
 153 # adds leading zeroes to hours, minutes and seconds
 154 # two zeroes
 155   for (@tmp[0,1,2]) {
 156     s/^/00/;
 157     s/^.*(..)$/$1/;
 158   }
 159
 160 # adds three leading zeroes
 161   for (@tmp[3]) {
 162     s/^/000/;
 163     s/^.*(...)$/$1/;
 164   }
 165
 166   return @tmp;
 167 }
 168
 169 # unfolds a time value, split it by its fields, deleting leading 0's in each
 170 # field
 171 # example: time_unfold("00:00:00,300") = ('00', '00', '00', '300')
 172 sub
 173 time_unfold
 174 {
 175   my ($_) = @_;
 176   return (/^([[:digit:]]+):([[:digit:]]+):([[:digit:]]+),([[:digit:]]+)$/);
 177 }
 178
 179 # joins a time value (splitted in a list)
 180 # for adding leading zeroes see add_zeroes()
 181 # example: time_fold("0:0:0,300") = "0:0:0,300"
 182 sub
 183 time_fold
 184 {
 185   return (join ':', @_[0,1,2]) . "," . $_[3];
 186 }
 187
 188 # low level function
 189 # adds two times (expressed in two arrays ...)
 190 # time_add([$hour1, $minute1, $second1, $millisecond1],
 191 #          [$hour2, $minute2, $second2, $millisecond2]) =
 192 #         ($hour1 + $hour2, $minute1 + $minute2, $second1 + $second2,
 193 #          $millisecond1 + $millisecond2)
 194 sub
 195 _time_add
 196 {
 197   my ($time_one, $time_two) = @_;
 198
 199   my @time_one;
 200   my @time_two;
 201   my @time_new; # the result
 202
 203   @time_one = @$time_one;
 204   @time_two = @$time_two;
 205
 206 # proceed in a little endian order...
 207 # milliseconds
 208   $time_new[3] = ($time_one[3] + $time_two[3]) % 1000;
 209   $time_one[2]+= 1 if ($time_one[3] + $time_two[3]) > 1000;
 210
 211 # seconds
 212   $time_new[2] = ($time_one[2] + $time_two[2]) % 60;
 213   $time_one[1]+= 1 if ($time_one[2] + $time_two[2]) > 60;
 214
 215 # minutes
 216   $time_new[1] = ($time_one[1] + $time_two[1]) % 60;
 217   $time_one[0]+= 1 if ($time_one[1] + $time_two[1]) > 60;
 218 # hours
 219   $time_new[0] = $time_one[0] + $time_two[0];
 220 # we don't round hours...
 221
 222 # returns hours, minute, seconds, milliseconds
 223   return (@time_new[0,1,2,3]);
 224 }
 225
 226 sub
 227 _time_min
 228 {
 229   my ($time_one, $time_two) = @_;
 230
 231   my @time_one;
 232   my @time_two;
 233   my @time_new; # the result
 234
 235   @time_one = @$time_one;
 236   @time_two = @$time_two;
 237
 238 # proceed in a little endian order...
 239 # milliseconds
 240   $time_one[2]-= 1 if ($time_one[3] - $time_two[3]) < 0;
 241   $time_new[3] =  ($time_one[3] - $time_two[3] + 1000) % 1000;
 242
 243 # seconds
 244   $time_one[1]-= 1 if ($time_one[2] - $time_two[2]) < 0;
 245   $time_new[2] =  ($time_one[2] - $time_two[2] + 60) % 60;
 246
 247 # minutes
 248   $time_one[0]-= 1 if ($time_one[1] - $time_two[1]) < 0;
 249   $time_new[1] =  ($time_one[1] - $time_two[1] + 60) % 60;
 250
 251 # hours
 252   $time_new[0] =  $time_one[0] - $time_two[0];
 253 # we don't round hours...
 254
 255 # returns hours, minute, seconds, milliseconds
 256   return (@time_new[0,1,2,3]);
 257 }