RequestHandlers for Picasso. Blog post about RequestHandlers: http://lucasr.org/2014/09/23/new-features-in-picasso/

ArtworkRequestHandler.java

import android.media.MediaMetadataRetriever;

import com.squareup.picasso.Picasso;
import com.squareup.picasso.Request;
import com.squareup.picasso.RequestHandler;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;


/**
 * Created by braunster on 13.07.15.
 */
public class ArtworkRequestHandler extends RequestHandler {

    @Override
    public boolean canHandleRequest(Request data) {
        return data.uri != null && (data.uri.getScheme() == null || data.uri.getScheme().equals("file")) && (data.uri.getPath().contains(".mp3"));
    }

    @Override
    public Result load(Request request, int networkPolicy) throws IOException {

        MediaMetadataRetriever myRetriever = new MediaMetadataRetriever();

        myRetriever.setDataSource(request.uri.getPath()); // the URI of audio file

        byte[] artwork = myRetriever.getEmbeddedPicture();

        if (artwork == null || artwork.length < 0) {
            throw new IOException("cant load artwork");
        }

        InputStream is = new ByteArrayInputStream(artwork);

        return new Result(is, Picasso.LoadedFrom.DISK);
    }
}

PicassoExample.java

public Picasso getInstance(Context context){
   return new Picasso.Builder(context)
                    .indicatorsEnabled(true)
                    .addRequestHandler(new ArtworkRequestHandler())
                    .addRequestHandler(new VideoRequestHandler())
                    .build();
}

VideoRequestHandler.java

import android.media.ThumbnailUtils;
import android.provider.MediaStore;

import com.squareup.picasso.Picasso;
import com.squareup.picasso.Request;
import com.squareup.picasso.RequestHandler;

import java.io.IOException;

/**
 * Created by braunster on 14.07.15.
 */
public class VideoRequestHandler extends RequestHandler {

    @Override
    public boolean canHandleRequest(Request data) {
        return data.uri != null && (data.uri.getScheme() == null || data.uri.getScheme().equals("file")) && (data.uri.getPath().contains(".mp4"));
    }

    @Override
    public Result load(Request request, int networkPolicy) throws IOException {
        return new Result(ThumbnailUtils.createVideoThumbnail(request.uri.getPath(), MediaStore.Images.Thumbnails.MINI_KIND), Picasso.LoadedFrom.DISK);
    }
}