[android] 如何获取media文件的meta data信息

标签：metadata

在app开发过程中，经常需要显示media文件的meta data信息，我们如何获取这些信息呢？

MediaStore

首先想到的就是MediaStore类了，它为我们提供的丰富的属性，我们只要通过sqlite操作，就能获取这些属性提供的值啦。

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
	};

不知道如何查询系统数据库数据？查查ContentResolver怎么使用吧
不过有时候，这些属性还不能满足我们的需求，这时候就需要一些其他类来帮助了。那么，来看看其他类吧

MediaMetadataRetriever 类

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

简单来说，我们可以重MediaMetadataRetriever类中获取meta data信息，关键是这些meta data信息是MediaStore类提供不了的，看看这个类能为我们提供哪些属性，写一个小demon测试下

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); // 从api level 14才有，即从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();  
        }  
	}

然后，分别拿一个video和audio文件测试一下，结果如下：

video：找了一个mp4文件

04-16 11:00:04.997: D/MediaMetadataRetreiverDemon(15813): str:/storage/emulated/0/DCIM/100MEDIA/VIDEO0001.mp4
04-16 11:00:05.027: D/MediaMetadataRetreiverDemon(15813): album:null
04-16 11:00:05.027: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_ALBUMARTIST:null
04-16 11:00:05.027: D/MediaMetadataRetreiverDemon(15813): artist:null
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_AUTHOR:null
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): bitrate:21230041
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_CD_TRACK_NUMBER:null
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_COMPILATION:null
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_COMPOSER:null
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_DATE:20150416T021157.000Z
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_DISC_NUMBER:null
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_DURATION:11869
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_GENRE:null
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_HAS_AUDIO:yes
04-16 11:00:05.037: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_HAS_VIDEO:yes
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_LOCATION:null
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_MIMETYPE:video/mp4
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_NUM_TRACKS:2
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_TITLE:null
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_VIDEO_HEIGHT:1080
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_VIDEO_ROTATION:270
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_VIDEO_WIDTH:1920
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_WRITER:null
04-16 11:00:05.047: D/MediaMetadataRetreiverDemon(15813): METADATA_KEY_YEAR:null

audio：找了一个mp3文件

04-16 11:09:10.119: D/MediaMetadataRetreiverDemon(17550): str:/storage/emulated/0/Music/Nero MediaHome/Maid with the Flaxen Hair.mp3
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): album:Fine Music, Vol. 1
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_ALBUMARTIST:Richard Stoltzman
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): artist:Richard Stoltzman/Slovak Radio Symphony Orchestra
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_AUTHOR:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): bitrate:192000
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_CD_TRACK_NUMBER:2
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_COMPILATION:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_COMPOSER:Claude Debussy
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_DATE:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_DISC_NUMBER:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_DURATION:169697
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_GENRE:(32)
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_HAS_AUDIO:yes
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_HAS_VIDEO:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_LOCATION:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_MIMETYPE:audio/mpeg
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_NUM_TRACKS:1
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_TITLE:Maid with the Flaxen Hair
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_VIDEO_HEIGHT:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_VIDEO_ROTATION:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_VIDEO_WIDTH:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_WRITER:null
04-16 11:09:10.139: D/MediaMetadataRetreiverDemon(17550): METADATA_KEY_YEAR:2008

有这么多属性可以查到，应该够我们用了吧

知道了video和audio，还有image类型的文件呢，看看这个类ExifInterface

ExifInterface

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

如何使用这个类，很简单：

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

然后再来看看exifInterface为我们提供了哪些属性查询吧

http://developer.android.com/reference/android/media/ExifInterface.html

包括camera、gps信息，以及其他一些专业数据

通过这些工具，我们就基本能解决获取meta data信息的问题啦~

[android] 如何获取media文件的meta data信息

标签：metadata

原文地址：http://blog.csdn.net/vic_fang/article/details/45096621