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I'm trying to display a set of Bitmaps using an AnimationDrawable object. For some reason, some of the images are missing when the view is rendered in the UI:

...
MediaMetadataRetriever retriever = new MediaMetadataRetriever();
retriever.setDataSource(mContext, videoUri);
...
AnimationDrawable frameAnimation = new AnimationDrawable();
for(int i=0; i < numberOfFrames; i++) {
    Bitmap frame = retriever.getFrameAtTime(i * 500 * 1000); // get 2 frames per second
    frameAnimation.addFrame(new BitmapDrawable(getResources(), frame), 100); // 
}
...
frameAnimation.setOneShot(false);
frameAnimation.start();

Calling frameAnimation.getNumberOfFrames() returns the correct number of frames (say 4 for a 2 second clip).

The problem is frameAnimation.start() only shows a subset of those frames in the UI (for instance frameAnimation could have 17 frames and only play through 4 of them).

Any ideas why the AnimationDrawable object is missing Bitmaps when looping through its frames?

Thanks!

mmBs
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Cat
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  • Using your 17 and 4 numbers, and with your frame duration of 100ms, is the animation looping after 400ms or 1700ms? IOW, is it truly skipping frames (which would result in a loop time of 400ms), or are frames not changing (which would result in a loop time of 1700ms)? If it is the latter, are you sure that the problem isn't with `getFrameAtTime()`, such as it returning the same `Bitmap` for multiple frame times? – CommonsWare May 03 '14 at 22:57
  • @CommonsWare Using the same example (4 frames displayed every 100ms with 17 recorded in total), I see 4 frames in 400 ms and then the animation restarts. It looks like it's skipping the in-between frames. – Cat May 03 '14 at 23:07
  • That's really strange. Looking at [the source code](https://android.googlesource.com/platform/frameworks/base/+/refs/heads/master/graphics/java/android/graphics/drawable/AnimationDrawable.java), if `getNumberOfFrames()` is indeed returning 17, I cannot see how it would wind up repeating after only 4. Make sure that you check `getNumberOfFrames()` sometime after those first 400ms have elapsed -- perhaps somehow things are getting clobbered between when you are checking `getNumberOfFrames()` and then. – CommonsWare May 03 '14 at 23:14
  • I called getNumberOfFrames() before `frameAnimation.start()` and it always returns a higher number than the bitmaps rendered on the screen. I also wrote a function to check that the bitmaps are unique, and it seems so. I'll probably have to dump the images on the disk and manually check that they are indeed recorded properly. – Cat May 03 '14 at 23:32

0 Answers0