src/lib/ffmpeg_subtitle_stream.cc

   1 /*
   2     Copyright (C) 2013-2016 Carl Hetherington <cth@carlh.net>
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include "ffmpeg_subtitle_stream.h"
  21 #include "raw_convert.h"
  22 #include <libxml++/libxml++.h>
  23 #include <boost/foreach.hpp>
  24 #include <iostream>
  25
  26 using std::string;
  27 using std::map;
  28 using std::list;
  29 using std::cout;
  30
  31 /** Construct a SubtitleStream from a value returned from to_string().
  32  *  @param t String returned from to_string().
  33  *  @param v State file version.
  34  */
  35 FFmpegSubtitleStream::FFmpegSubtitleStream (cxml::ConstNodePtr node, int version)
  36         : FFmpegStream (node)
  37 {
  38         if (version == 32) {
  39                 BOOST_FOREACH (cxml::NodePtr i, node->node_children ("Period")) {
  40                         /* In version 32 we assumed that from times were unique, so they were
  41                            used as identifiers.  All subtitles were image subtitles.
  42                         */
  43                         add_image_subtitle (
  44                                 raw_convert<string> (i->string_child ("From")),
  45                                 ContentTimePeriod (
  46                                         ContentTime (i->number_child<ContentTime::Type> ("From")),
  47                                         ContentTime (i->number_child<ContentTime::Type> ("To"))
  48                                         )
  49                                 );
  50                 }
  51         } else {
  52                 /* In version 33 we use a hash of various parts of the subtitle as the id.
  53                    <Subtitle> was initially used for image subtitles; later we have
  54                    <ImageSubtitle> and <TextSubtitle>
  55                 */
  56                 BOOST_FOREACH (cxml::NodePtr i, node->node_children ("Subtitle")) {
  57                         add_image_subtitle (
  58                                 raw_convert<string> (i->string_child ("Id")),
  59                                 ContentTimePeriod (
  60                                         ContentTime (i->number_child<ContentTime::Type> ("From")),
  61                                         ContentTime (i->number_child<ContentTime::Type> ("To"))
  62                                         )
  63                                 );
  64                 }
  65
  66                 BOOST_FOREACH (cxml::NodePtr i, node->node_children ("ImageSubtitle")) {
  67                         add_image_subtitle (
  68                                 raw_convert<string> (i->string_child ("Id")),
  69                                 ContentTimePeriod (
  70                                         ContentTime (i->number_child<ContentTime::Type> ("From")),
  71                                         ContentTime (i->number_child<ContentTime::Type> ("To"))
  72                                         )
  73                                 );
  74                 }
  75
  76                 BOOST_FOREACH (cxml::NodePtr i, node->node_children ("TextSubtitle")) {
  77                         add_text_subtitle (
  78                                 raw_convert<string> (i->string_child ("Id")),
  79                                 ContentTimePeriod (
  80                                         ContentTime (i->number_child<ContentTime::Type> ("From")),
  81                                         ContentTime (i->number_child<ContentTime::Type> ("To"))
  82                                         )
  83                                 );
  84                 }
  85         }
  86 }
  87
  88 void
  89 FFmpegSubtitleStream::as_xml (xmlpp::Node* root) const
  90 {
  91         FFmpegStream::as_xml (root);
  92
  93         as_xml (root, _image_subtitles, "ImageSubtitle");
  94         as_xml (root, _text_subtitles, "TextSubtitle");
  95 }
  96
  97 void
  98 FFmpegSubtitleStream::as_xml (xmlpp::Node* root, PeriodMap const & subs, string node_name) const
  99 {
 100         for (PeriodMap::const_iterator i = subs.begin(); i != subs.end(); ++i) {
 101                 xmlpp::Node* node = root->add_child (node_name);
 102                 node->add_child("Id")->add_child_text (i->first);
 103                 node->add_child("From")->add_child_text (raw_convert<string> (i->second.from.get ()));
 104                 node->add_child("To")->add_child_text (raw_convert<string> (i->second.to.get ()));
 105         }
 106 }
 107
 108 void
 109 FFmpegSubtitleStream::add_image_subtitle (string id, ContentTimePeriod period)
 110 {
 111         DCPOMATIC_ASSERT (_image_subtitles.find (id) == _image_subtitles.end ());
 112         _image_subtitles[id] = period;
 113 }
 114
 115 void
 116 FFmpegSubtitleStream::add_text_subtitle (string id, ContentTimePeriod period)
 117 {
 118         DCPOMATIC_ASSERT (_text_subtitles.find (id) == _text_subtitles.end ());
 119         _text_subtitles[id] = period;
 120 }
 121
 122 list<ContentTimePeriod>
 123 FFmpegSubtitleStream::image_subtitles_during (ContentTimePeriod period, bool starting) const
 124 {
 125         return subtitles_during (period, starting, _image_subtitles);
 126 }
 127
 128 list<ContentTimePeriod>
 129 FFmpegSubtitleStream::text_subtitles_during (ContentTimePeriod period, bool starting) const
 130 {
 131         return subtitles_during (period, starting, _text_subtitles);
 132 }
 133
 134 list<ContentTimePeriod>
 135 FFmpegSubtitleStream::subtitles_during (ContentTimePeriod period, bool starting, PeriodMap const & subs) const
 136 {
 137         list<ContentTimePeriod> d;
 138
 139         /* XXX: inefficient */
 140         for (map<string, ContentTimePeriod>::const_iterator i = subs.begin(); i != subs.end(); ++i) {
 141                 if ((starting && period.contains (i->second.from)) || (!starting && period.overlaps (i->second))) {
 142                         d.push_back (i->second);
 143                 }
 144         }
 145
 146         return d;
 147 }
 148
 149 ContentTime
 150 FFmpegSubtitleStream::find_subtitle_to (string id) const
 151 {
 152         PeriodMap::const_iterator i = _image_subtitles.find (id);
 153         if (i != _image_subtitles.end ()) {
 154                 return i->second.to;
 155         }
 156
 157         i = _text_subtitles.find (id);
 158         DCPOMATIC_ASSERT (i != _text_subtitles.end ());
 159         return i->second.to;
 160 }
 161
 162 /** Add some offset to all the times in the stream */
 163 void
 164 FFmpegSubtitleStream::add_offset (ContentTime offset)
 165 {
 166         for (PeriodMap::iterator i = _image_subtitles.begin(); i != _image_subtitles.end(); ++i) {
 167                 i->second.from += offset;
 168                 i->second.to += offset;
 169         }
 170
 171         for (PeriodMap::iterator i = _text_subtitles.begin(); i != _text_subtitles.end(); ++i) {
 172                 i->second.from += offset;
 173                 i->second.to += offset;
 174         }
 175 }