[android] 如何擷取media檔案的meta data資訊

[android] 如何擷取media檔案的meta data資訊

在app開發過程中，經常需要顯示media檔案的meta data資訊，我們如何擷取這些資訊呢？

 

MediaStore

首先想到的就是MediaStore類了，它為我們提供的豐富的屬性，我們只要通過sqlite操作，就能擷取這些屬性提供的值啦。

 

public static final String[] ItemImageProjection = new String[] {MediaStore.Images.ImageColumns.DISPLAY_NAME,MediaStore.Images.ImageColumns.DATA,MediaStore.Images.ImageColumns.SIZE,MediaStore.Images.ImageColumns._ID,MediaStore.Images.ImageColumns.MIME_TYPE};public static final String[] ItemVideoProjection = new String[] {MediaStore.Video.VideoColumns.DISPLAY_NAME,MediaStore.Video.VideoColumns.DATA,MediaStore.Video.VideoColumns.SIZE,MediaStore.Video.VideoColumns._ID,MediaStore.Video.VideoColumns.MIME_TYPE};public static final String[] ItemAudioProjection = new String[] {MediaStore.Audio.AudioColumns.DISPLAY_NAME,MediaStore.Audio.AudioColumns.DATA,MediaStore.Audio.AudioColumns.SIZE,MediaStore.Audio.AudioColumns._ID,MediaStore.Audio.AudioColumns.MIME_TYPE};

 

不知道如何查詢系統資料庫資料？查查ContentResolver怎麼使用吧
不過有時候，這些屬性還不能滿足我們的需求，這時候就需要一些其他類來協助了。那麼，來看看其他類吧

 

MediaMetadataRetriever 類

SDK官方說明：MediaMetadataRetriever class provides a unified interface for retrieving frame and meta data from an input media file.

 

 

簡單來說，我們可以重MediaMetadataRetriever類中擷取meta data資訊，關鍵是這些meta data資訊是MediaStore類提供不了的，看看這個類能為我們提供哪些屬性，寫一個小demon測試下

 

public void getMetadata(String path){MediaMetadataRetriever mmr = new MediaMetadataRetriever();          Log.d(TAG, str: + path);          try {              mmr.setDataSource(path);                     String album = mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_ALBUM);              Log.d(TAG, album: + album);              Log.d(TAG, METADATA_KEY_ALBUMARTIST: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_ALBUMARTIST));            String artist = mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_ARTIST);              Log.d(TAG, artist: + artist);             Log.d(TAG, METADATA_KEY_AUTHOR: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_AUTHOR));            String bitrate = mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_BITRATE); // 從api level 14才有，即從ICS4.0才有此功能              Log.d(TAG, bitrate: +bitrate);              Log.d(TAG, METADATA_KEY_CD_TRACK_NUMBER: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_CD_TRACK_NUMBER));            Log.d(TAG, METADATA_KEY_COMPILATION: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_COMPILATION));            Log.d(TAG, METADATA_KEY_COMPOSER: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_COMPOSER));            Log.d(TAG, METADATA_KEY_DATE: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_DATE));            Log.d(TAG, METADATA_KEY_DISC_NUMBER: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_DISC_NUMBER));            Log.d(TAG, METADATA_KEY_DURATION: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_DURATION));            Log.d(TAG, METADATA_KEY_GENRE: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_GENRE));            Log.d(TAG, METADATA_KEY_HAS_AUDIO: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_HAS_AUDIO));            Log.d(TAG, METADATA_KEY_HAS_VIDEO: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_HAS_VIDEO));            Log.d(TAG, METADATA_KEY_LOCATION: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_LOCATION));            Log.d(TAG, METADATA_KEY_MIMETYPE: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_MIMETYPE));                    Log.d(TAG, METADATA_KEY_NUM_TRACKS: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_NUM_TRACKS));            Log.d(TAG, METADATA_KEY_TITLE: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_TITLE));            Log.d(TAG, METADATA_KEY_VIDEO_HEIGHT: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_VIDEO_HEIGHT));            Log.d(TAG, METADATA_KEY_VIDEO_ROTATION: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_VIDEO_ROTATION));            Log.d(TAG, METADATA_KEY_VIDEO_WIDTH: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_VIDEO_WIDTH));            Log.d(TAG, METADATA_KEY_WRITER: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_WRITER));            Log.d(TAG, METADATA_KEY_YEAR: + mmr.extractMetadata(MediaMetadataRetriever.METADATA_KEY_YEAR));        } catch (IllegalArgumentException e) {              // TODO Auto-generated catch block              e.printStackTrace();          } catch (IllegalStateException e) {              // TODO Auto-generated catch block              e.printStackTrace();          }  }

 

然後，分別拿一個video和audio檔案測試一下，結果如下：

video：找了一個mp4檔案

 

04-16 11:00:04.997: D/MediaMetadataRetreiverDemon(15813): str:/storage/emulated/0/DCIM/100MEDIA/VIDEO0001.mp404-16 11:00:05.027: D/MediaMetadataRetreiverDemon(15813): album:null04-16 11:00:05.027: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_ALBUMARTIST:null04-16 11:00:05.027: D/MediaMetadataRetreiverDemon(15813): artist:null04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_AUTHOR:null04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): bitrate:2123004104-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_CD_TRACK_NUMBER:null04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_COMPILATION:null04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_COMPOSER:null04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_DATE:20150416T021157.000Z04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_DISC_NUMBER:null04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_DURATION:1186904-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_GENRE:null04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_HAS_AUDIO:yes04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_HAS_VIDEO:yes04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_LOCATION:null04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_MIMETYPE:video/mp404-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_NUM_TRACKS:204-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_TITLE:null04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_VIDEO_HEIGHT:108004-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_VIDEO_ROTATION:27004-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_VIDEO_WIDTH:192004-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_WRITER:null04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_YEAR:null

 

audio：找了一個mp3檔案

 

04-16 11:09:10.119: D/MediaMetadataRetreiverDemon(17550): str:/storage/emulated/0/Music/Nero MediaHome/Maid with the Flaxen Hair.mp304-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): album:Fine Music, Vol. 104-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_ALBUMARTIST:Richard Stoltzman04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): artist:Richard Stoltzman/Slovak Radio Symphony Orchestra04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_AUTHOR:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): bitrate:19200004-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_CD_TRACK_NUMBER:204-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_COMPILATION:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_COMPOSER:Claude Debussy04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_DATE:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_DISC_NUMBER:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_DURATION:16969704-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_GENRE:(32)04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_HAS_AUDIO:yes04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_HAS_VIDEO:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_LOCATION:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_MIMETYPE:audio/mpeg04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_NUM_TRACKS:104-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_TITLE:Maid with the Flaxen Hair04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_VIDEO_HEIGHT:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_VIDEO_ROTATION:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_VIDEO_WIDTH:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_WRITER:null04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_YEAR:2008

 

有這麼多屬性可以查到，應該夠我們用了吧

 

知道了video和audio，還有image類型的檔案呢，看看這個類ExifInterface

 

ExifInterface

sdk官方解釋：This is a class for reading and writing Exif tags in a JPEG file.

 

如何使用這個類，很簡單：

 

ExifInterface exifInterface;try {exifInterface = new ExifInterface(path);} catch (IOException e) {return;}exifInterface.getAttribute(ExifInterface.TAG_MODEL);

 

然後再來看看exifInterface為我們提供了哪些屬性查詢吧