MediaMetadataRetriever setDataSource throws Illega

问题:

I'm trying to get the size of a remote video using this class and i'm getting IllegalArgumentException if the video is remote.

the video is an mp4 stored in one server...

the video plays correctly if i play it with mediaplayer, but it gives the error if i try to do this:

try {
    MediaMetadataRetriever retriever = new  MediaMetadataRetriever();
    Bitmap bmp = null;      
    retriever.setDataSource(context, uri);
    bmp = retriever.getFrameAtTime();           
    videoHeight = (int) (bmp.getHeight()*((float)getIntWidth()/bmp.getWidth()));
} catch (Exception e) {
    e.printStackTrace();
}   

the error is thrown in this line:

retriever.setDataSource(context, uri);

and uri contains Uri.parse("http://www.myweb.com/myvideo.mp4");

what is wrong in the code?

12-19 13:38:08.610: W/System.err(13333): java.lang.IllegalArgumentException
12-19 13:38:08.611: W/System.err(13333):    at android.media.MediaMetadataRetriever.setDataSource(MediaMetadataRetriever.java:175)

回答1:

Maybe you are running into this bug. If so try:

try {
    MediaMetadataRetriever retriever = new  MediaMetadataRetriever();
    Bitmap bmp = null;      
    retriever.setDataSource("http://www.myweb.com/myvideo.mp4", new HashMap<String, String>());
    bmp = retriever.getFrameAtTime();           
    videoHeight = (int) (bmp.getHeight()*((float)getIntWidth()/bmp.getWidth()));
} catch (Exception e) {
    e.printStackTrace();
}

If that doesn't work you can always try FFmpegMediaMetadataRetriever:

FFmpegMediaMetadataRetriever retriever = new  FFmpegMediaMetadataRetriever();

try {
    Bitmap bmp = null;      
    retriever.setDataSource("http://www.myweb.com/myvideo.mp4"));
    bmp = retriever.getFrameAtTime();           
    videoHeight = (int) (bmp.getHeight()*((float)getIntWidth()/bmp.getWidth()));
} catch (Exception e) {
    e.printStackTrace();
}

retriever.release();

回答2:

In my case, I was creating a simple metadata extraction test app, so I copied a file to my phone using adb, like so:

adb push 350950598.mp4 /sdcard/Movies

but I forgot to add the read external storage directory permission in the app manifest.

Specifically:

<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="my.cool.package.name">
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    ...
</manifest>

Adding those permissions fixed it for me, even for the simple file string call:

    MediaMetadataRetriever mediaMetadataRetriever = new MediaMetadataRetriever();
    mediaMetadataRetriever.setDataSource(movie.getPath());

And of course, if you're targeting API 23+ marshmallow then you'll have to dynamically ask for those permissions, as well.