Media: Add thumbnail extraction to AudioVideoMetadataExtractor.

media/base/audio_video_metadata_extractor.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/base/audio_video_metadata_extractor.h"
 
 #include "base/bind.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
 #include "base/time/time.h"
@@ skipping 29 matching lines @@
 
   int temporary = -1;
   if (*destination < 0 && base::StringToInt(tag->value, &temporary) &&
       temporary >= 0) {
     *destination = temporary;
   }
 
   return true;
 }
 
+// Set attached image size limit to 4MB. Chosen arbitrarily.
+const int kAttachedImageSizeLimit = 4 * 1024 * 1024;
+
 }  // namespace
 
 AudioVideoMetadataExtractor::StreamInfo::StreamInfo() {}
 
 AudioVideoMetadataExtractor::StreamInfo::~StreamInfo() {}
 
 AudioVideoMetadataExtractor::AudioVideoMetadataExtractor()
     : extracted_(false),
       duration_(-1),
       width_(-1),
       height_(-1),
       disc_(-1),
       rotation_(-1),
       track_(-1) {
 }
 
 AudioVideoMetadataExtractor::~AudioVideoMetadataExtractor() {
 }
 
-bool AudioVideoMetadataExtractor::Extract(DataSource* source) {
+bool AudioVideoMetadataExtractor::Extract(DataSource* source,
+                                          bool extract_attached_images) {
   DCHECK(!extracted_);
 
   bool read_ok = true;
   media::BlockingUrlProtocol protocol(source, base::Bind(&OnError, &read_ok));
   media::FFmpegGlue glue(&protocol);
   AVFormatContext* format_context = glue.format_context();
 
   if (!glue.OpenContext())
     return false;
 
@@ skipping 24 matching lines @@
 
     // Extract dictionary from streams also. Needed for containers that attach
     // metadata to contained streams instead the container itself, like OGG.
     ExtractDictionary(stream->metadata, &info.tags);
 
     if (!stream->codec)
       continue;
 
     info.type = avcodec_get_name(stream->codec->codec_id);
 
-    // Extract dimensions of largest stream that's not an attached picture.
+    // Extract dimensions of largest stream that's not an attached image.
     if (stream->codec->width > 0 && stream->codec->width > width_ &&
         stream->codec->height > 0 && stream->codec->height > height_) {
       width_ = stream->codec->width;
       height_ = stream->codec->height;
     }
+
+    // Extract attached image if requested.
+    if (extract_attached_images &&
+        stream->disposition == AV_DISPOSITION_ATTACHED_PIC &&
+        stream->attached_pic.size > 0 &&
+        stream->attached_pic.size <= kAttachedImageSizeLimit &&
+        stream->attached_pic.data != NULL) {
+      attached_images_bytes_.push_back(std::string());
+      attached_images_bytes_.back().assign(
+          reinterpret_cast<const char*>(stream->attached_pic.data),
+          stream->attached_pic.size);
+    }
   }
 
   extracted_ = true;
   return true;
 }
 
 double AudioVideoMetadataExtractor::duration() const {
   DCHECK(extracted_);
   return duration_;
 }
@@ skipping 72 matching lines @@
   DCHECK(extracted_);
   return track_;
 }
 
 const std::vector<AudioVideoMetadataExtractor::StreamInfo>&
 AudioVideoMetadataExtractor::stream_infos() const {
   DCHECK(extracted_);
   return stream_infos_;
 }
 
+const std::vector<std::string>&
+AudioVideoMetadataExtractor::attached_images_bytes() const {
+  DCHECK(extracted_);
+  return attached_images_bytes_;
+}
+
 void AudioVideoMetadataExtractor::ExtractDictionary(
     AVDictionary* metadata, TagDictionary* raw_tags) {
   if (!metadata)
     return;
 
   AVDictionaryEntry* tag = NULL;
   while ((tag = av_dict_get(metadata, "", tag, AV_DICT_IGNORE_SUFFIX))) {
     if (raw_tags->find(tag->key) == raw_tags->end())
       (*raw_tags)[tag->key] = tag->value;
 
     if (ExtractInt(tag, "rotate", &rotation_)) continue;
     if (ExtractString(tag, "album", &album_)) continue;
     if (ExtractString(tag, "artist", &artist_)) continue;
     if (ExtractString(tag, "comment", &comment_)) continue;
     if (ExtractString(tag, "copyright", &copyright_)) continue;
     if (ExtractString(tag, "date", &date_)) continue;
     if (ExtractInt(tag, "disc", &disc_)) continue;
     if (ExtractString(tag, "encoder", &encoder_)) continue;
     if (ExtractString(tag, "encoded_by", &encoded_by_)) continue;
     if (ExtractString(tag, "genre", &genre_)) continue;
     if (ExtractString(tag, "language", &language_)) continue;
     if (ExtractString(tag, "title", &title_)) continue;
     if (ExtractInt(tag, "track", &track_)) continue;
   }
 }
 
 }  // namespace media