how can I show a video thumbnail from a video path?

问题

I want to show a video thumbnail in an ImageView from a video path on storage. Is there a function that takes a video path and returns a bitmap of a thumbnail? I get the video path by this code:

public ArrayList<String> getAllMedia() {
  HashSet<String> videoItemHashSet = new HashSet<>();
  String[] projection = {MediaStore.Video.VideoColumns.DATA, MediaStore.Video.Media.DISPLAY_NAME};
  Cursor cursor = getContext().getContentResolver().query(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, projection, null, null, null);
  try {
    cursor.moveToFirst();
    do {
      videoItemHashSet.add((cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DATA))));
    } while(cursor.moveToNext());
    cursor.close();
  } catch(Exception e) {
    e.printStackTrace();
  }
  ArrayList<String> downloadedList = new ArrayList<>(videoItemHashSet);
  return downloadedList;
}

回答1:

It is the default way to create a thumbnail.

For Mini Kind

Bitmap thumb;
//MINI_KIND, size:  512 x 384 thumbnail 
    thumb = ThumbnailUtils.createVideoThumbnail(filePath, MediaStore.Video.Thumbnails.MINI_KIND);
            img_tumbnail.setImageBitmap(thumb);

For Micro Kind

Bitmap thumb;
//MICRO_KIND, size: 96 x 96 thumbnail
thumb= ThumbnailUtils.createVideoThumbnail(filePath, Thumbnails.MICRO_KIND);
img_tumbnail.setImageBitmap(thumb);

Also, you can use Glide for Url as well as Video path of Device.

Glide.with(context).with(this)
                    .asBitmap()
                    .load(videoFilePath) // or URI/path
                    .into(imgView); //imageview to set thumbnail to

also, you can resize thumbnail by using .override(50,50) with Glide.

回答2:

Use Glide lib

to show thumbnail from local storage

String filePath = "/storage/emulated/0/Pictures/example_video.mp4";

GlideApp  
    .with(context)
    .asBitmap()
    .load(Uri.fromFile(new File(filePath)))
    .into(imageViewGifAsBitmap);

回答3:

I have 3rd method to set thumbnail of image/video. Hope it will help you.

1) ThumbnailUtils --> Effective but Slow

Bitmap thumb = ThumbnailUtils.createVideoThumbnail(thumbPath, MediaStore.Video.Thumbnails.MINI_KIND);
        holder.ivThumb.setImageBitmap(thumb);

2) FFmpegMediaMetadataRetriever --> Very Effective but Slow

FFmpegMediaMetadataRetriever retriever = new FFmpegMediaMetadataRetriever();
    try {
        retriever.setDataSource(thumbPath);
       thumb.setImageBitmap(retriever.getFrameAtTime(0));
    } catch (Exception ex) {
        // Assume this is a corrupt  file
    }

3) Glide --> Effective and Fast

   RequestOptions options = new RequestOptions()
            .centerCrop()
            .placeholder(android.R.drawable.stat_notify_error)
            .error(android.R.drawable.stat_notify_error);

    Glide.with(context)
            .load(thumPath)
            .apply(options)
            .into(thumb);

回答4:

In some devices not working for me without FileDescriptorBitmapDecoder

So I used following code with FileDescriptorBitmapDecoder

 public static void loadLocalVideoThumbanail(Context context, String path, final ImageView imageView) {
    try {
        if (path == null || path.isEmpty())
            return;

        BitmapPool bitmapPool = Glide.get(context).getBitmapPool();
        int microSecond = 1000000;// 1st second as an example
        VideoBitmapDecoder videoBitmapDecoder = new VideoBitmapDecoder(microSecond);
        FileDescriptorBitmapDecoder fileDescriptorBitmapDecoder = new FileDescriptorBitmapDecoder(videoBitmapDecoder, bitmapPool, DecodeFormat.PREFER_ARGB_8888);


        Glide.with(context).load(path).asBitmap().thumbnail(0.6f)
                .diskCacheStrategy(DiskCacheStrategy.RESULT)
                .dontAnimate()
                .videoDecoder(fileDescriptorBitmapDecoder)
                .override(200,200)
                .into(imageView);
    } catch (Exception e) {
        MyLog.e(TAG, "LoadImage: ", e);
    }
}

回答5:

You can use ThumbnailUtils to load video thumb in 3 format:

• MINI_KIND : Good for media detail view
• FULL_SCREEN_KIND : Good for header
• MICRO_KIND : Good for recycleView

Ex:

holder.videoThumb.setImageBitmap(ThumbnailUtils.createVideoThumbnail(getItem(position).videoURL, MediaStore.Images.Thumbnails.MICRO_KIND))

The biggest drawback is that ThumbnailUtils operate on UI thread so if you try to use this method in a recycleView then it gone make your app skip frames. Your RecycleView will have laggy scroll and if you have more than 7 items then your app will start throwing ANR.

That means you need to create AsyncTask or Threads which again might lead to memory leaks.

Conclusion; Glide is better in loading video thumbs.

Here DiskCacheStrategy.RESULT is important parameter which worked for me and give a smooth fast scroll in recycle view.

            Glide.with(context).load(getItem(position).videoURL)
                    .asBitmap()
                    .placeholder(R.drawable.app_icon)
                    .centerCrop()
                    .diskCacheStrategy(DiskCacheStrategy.RESULT)
                    .into(holder.videoThumb)

来源：https://stackoverflow.com/questions/50073474/how-can-i-show-a-video-thumbnail-from-a-video-path