media/base/audio_video_metadata_extractor.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "media/base/audio_video_metadata_extractor.h"
   6
   7 #include "base/bind.h"
   8 #include "base/strings/string_number_conversions.h"
   9 #include "base/strings/string_util.h"
  10 #include "base/time/time.h"
  11 #include "media/ffmpeg/ffmpeg_common.h"
  12 #include "media/filters/blocking_url_protocol.h"
  13 #include "media/filters/ffmpeg_glue.h"
  14
  15 namespace media {
  16
  17 namespace {
  18
  19 void OnError(bool* succeeded) {
  20   *succeeded = false;
  21 }
  22
  23 // Returns true if the |tag| matches |expected_key|.
  24 bool ExtractString(AVDictionaryEntry* tag, const char* expected_key,
  25                    std::string* destination) {
  26   if (!LowerCaseEqualsASCII(std::string(tag->key), expected_key))
  27     return false;
  28
  29   if (destination->empty())
  30     *destination = tag->value;
  31
  32   return true;
  33 }
  34
  35 // Returns true if the |tag| matches |expected_key|.
  36 bool ExtractInt(AVDictionaryEntry* tag, const char* expected_key,
  37                 int* destination) {
  38   if (!LowerCaseEqualsASCII(std::string(tag->key), expected_key))
  39     return false;
  40
  41   int temporary = -1;
  42   if (*destination < 0 && base::StringToInt(tag->value, &temporary) &&
  43       temporary >= 0) {
  44     *destination = temporary;
  45   }
  46
  47   return true;
  48 }
  49
  50 // Set attached image size limit to 4MB. Chosen arbitrarily.
  51 const int kAttachedImageSizeLimit = 4 * 1024 * 1024;
  52
  53 }  // namespace
  54
  55 AudioVideoMetadataExtractor::StreamInfo::StreamInfo() {}
  56
  57 AudioVideoMetadataExtractor::StreamInfo::~StreamInfo() {}
  58
  59 AudioVideoMetadataExtractor::AudioVideoMetadataExtractor()
  60     : extracted_(false),
  61       duration_(-1),
  62       width_(-1),
  63       height_(-1),
  64       disc_(-1),
  65       rotation_(-1),
  66       track_(-1) {
  67 }
  68
  69 AudioVideoMetadataExtractor::~AudioVideoMetadataExtractor() {
  70 }
  71
  72 bool AudioVideoMetadataExtractor::Extract(DataSource* source,
  73                                           bool extract_attached_images) {
  74   DCHECK(!extracted_);
  75
  76   bool read_ok = true;
  77   media::BlockingUrlProtocol protocol(source, base::Bind(&OnError, &read_ok));
  78   media::FFmpegGlue glue(&protocol);
  79   AVFormatContext* format_context = glue.format_context();
  80
  81   if (!glue.OpenContext())
  82     return false;
  83
  84   if (!read_ok)
  85     return false;
  86
  87   if (!format_context->iformat)
  88     return false;
  89
  90   if (avformat_find_stream_info(format_context, NULL) < 0)
  91     return false;
  92
  93   if (format_context->duration != AV_NOPTS_VALUE)
  94     duration_ = static_cast<double>(format_context->duration) / AV_TIME_BASE;
  95
  96   stream_infos_.push_back(StreamInfo());
  97   StreamInfo& container_info = stream_infos_.back();
  98   container_info.type = format_context->iformat->name;
  99   ExtractDictionary(format_context->metadata, &container_info.tags);
 100
 101   for (unsigned int i = 0; i < format_context->nb_streams; ++i) {
 102     stream_infos_.push_back(StreamInfo());
 103     StreamInfo& info = stream_infos_.back();
 104
 105     AVStream* stream = format_context->streams[i];
 106     if (!stream)
 107       continue;
 108
 109     // Extract dictionary from streams also. Needed for containers that attach
 110     // metadata to contained streams instead the container itself, like OGG.
 111     ExtractDictionary(stream->metadata, &info.tags);
 112
 113     if (!stream->codec)
 114       continue;
 115
 116     info.type = avcodec_get_name(stream->codec->codec_id);
 117
 118     // Extract dimensions of largest stream that's not an attached image.
 119     if (stream->codec->width > 0 && stream->codec->width > width_ &&
 120         stream->codec->height > 0 && stream->codec->height > height_) {
 121       width_ = stream->codec->width;
 122       height_ = stream->codec->height;
 123     }
 124
 125     // Extract attached image if requested.
 126     if (extract_attached_images &&
 127         stream->disposition == AV_DISPOSITION_ATTACHED_PIC &&
 128         stream->attached_pic.size > 0 &&
 129         stream->attached_pic.size <= kAttachedImageSizeLimit &&
 130         stream->attached_pic.data != NULL) {
 131       attached_images_bytes_.push_back(std::string());
 132       attached_images_bytes_.back().assign(
 133           reinterpret_cast<const char*>(stream->attached_pic.data),
 134           stream->attached_pic.size);
 135     }
 136   }
 137
 138   extracted_ = true;
 139   return true;
 140 }
 141
 142 double AudioVideoMetadataExtractor::duration() const {
 143   DCHECK(extracted_);
 144   return duration_;
 145 }
 146
 147 int AudioVideoMetadataExtractor::width() const {
 148   DCHECK(extracted_);
 149   return width_;
 150 }
 151
 152 int AudioVideoMetadataExtractor::height() const {
 153   DCHECK(extracted_);
 154   return height_;
 155 }
 156
 157 int AudioVideoMetadataExtractor::rotation() const {
 158   DCHECK(extracted_);
 159   return rotation_;
 160 }
 161
 162 const std::string& AudioVideoMetadataExtractor::album() const {
 163   DCHECK(extracted_);
 164   return album_;
 165 }
 166
 167 const std::string& AudioVideoMetadataExtractor::artist() const {
 168   DCHECK(extracted_);
 169   return artist_;
 170 }
 171
 172 const std::string& AudioVideoMetadataExtractor::comment() const {
 173   DCHECK(extracted_);
 174   return comment_;
 175 }
 176
 177 const std::string& AudioVideoMetadataExtractor::copyright() const {
 178   DCHECK(extracted_);
 179   return copyright_;
 180 }
 181
 182 const std::string& AudioVideoMetadataExtractor::date() const {
 183   DCHECK(extracted_);
 184   return date_;
 185 }
 186
 187 int AudioVideoMetadataExtractor::disc() const {
 188   DCHECK(extracted_);
 189   return disc_;
 190 }
 191
 192 const std::string& AudioVideoMetadataExtractor::encoder() const {
 193   DCHECK(extracted_);
 194   return encoder_;
 195 }
 196
 197 const std::string& AudioVideoMetadataExtractor::encoded_by() const {
 198   DCHECK(extracted_);
 199   return encoded_by_;
 200 }
 201
 202 const std::string& AudioVideoMetadataExtractor::genre() const {
 203   DCHECK(extracted_);
 204   return genre_;
 205 }
 206
 207 const std::string& AudioVideoMetadataExtractor::language() const {
 208   DCHECK(extracted_);
 209   return language_;
 210 }
 211
 212 const std::string& AudioVideoMetadataExtractor::title() const {
 213   DCHECK(extracted_);
 214   return title_;
 215 }
 216
 217 int AudioVideoMetadataExtractor::track() const {
 218   DCHECK(extracted_);
 219   return track_;
 220 }
 221
 222 const std::vector<AudioVideoMetadataExtractor::StreamInfo>&
 223 AudioVideoMetadataExtractor::stream_infos() const {
 224   DCHECK(extracted_);
 225   return stream_infos_;
 226 }
 227
 228 const std::vector<std::string>&
 229 AudioVideoMetadataExtractor::attached_images_bytes() const {
 230   DCHECK(extracted_);
 231   return attached_images_bytes_;
 232 }
 233
 234 void AudioVideoMetadataExtractor::ExtractDictionary(
 235     AVDictionary* metadata, TagDictionary* raw_tags) {
 236   if (!metadata)
 237     return;
 238
 239   AVDictionaryEntry* tag = NULL;
 240   while ((tag = av_dict_get(metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
 241     if (raw_tags->find(tag->key) == raw_tags->end())
 242       (*raw_tags)[tag->key] = tag->value;
 243
 244     if (ExtractInt(tag, "rotate", &rotation_)) continue;
 245     if (ExtractString(tag, "album", &album_)) continue;
 246     if (ExtractString(tag, "artist", &artist_)) continue;
 247     if (ExtractString(tag, "comment", &comment_)) continue;
 248     if (ExtractString(tag, "copyright", &copyright_)) continue;
 249     if (ExtractString(tag, "date", &date_)) continue;
 250     if (ExtractInt(tag, "disc", &disc_)) continue;
 251     if (ExtractString(tag, "encoder", &encoder_)) continue;
 252     if (ExtractString(tag, "encoded_by", &encoded_by_)) continue;
 253     if (ExtractString(tag, "genre", &genre_)) continue;
 254     if (ExtractString(tag, "language", &language_)) continue;
 255     if (ExtractString(tag, "title", &title_)) continue;
 256     if (ExtractInt(tag, "track", &track_)) continue;
 257   }
 258 }
 259
 260 }  // namespace media