How to change video resolution with jcodec

Question

I need to reduce video resolution for some mp4 file, and I decide to use jcodec. I tried to search some example how to do this but not found any examples. Any information about this will be useful.

Did some research and jcodec was no made for android and you would get alot of problems.. You should use : http://stackoverflow.com/questions/2645041/ffmpeg-for-a-android-using-tutorial-ffmpeg-and-android-mk — Hansjörg Hofer, Sep 08 '13 at 20:32
`jcodec was no made for android` - [this isn't true](http://jcodec.org/news/no_deps.html). Also I can't use `ffmpeg` because I'm will port app to Blackberry10 — CAMOBAP, Sep 09 '13 at 05:12

score 2 · Accepted Answer · edited Mar 30 '14 at 15:51

I was looking for an answer to this too, but didn't find anything.

So I looked into the code and realized that scaling the Bitmap before passing it to JCodec solves the problem.

Here is the class I use. Please note that this is code for Android, which uses the latest JCodec for Android.

public class DDVideoEncoder  {

    private static final String TAG = DDVideoEncoder.class.getSimpleName();

    private SequenceEncoder encoder;


    public DDVideoEncoder(String filepath) throws IOException, OutOfMemoryError {
        File out = new File(filepath);
        encoder = new SequenceEncoder(out);

    }

    // returns false on out of memory error.
    public Boolean addFrame(String filePath, int newSize) throws IOException {

        // newSize indicates size of bitmap in percent
        Bitmap bi = getResizedBitmap(filePath, newSize);

        try { encoder.encodeImage(bi); }
        catch (OutOfMemoryError outOfMemoryError) { Log.d(TAG, "encodeImage:" + outOfMemoryError); return  false; }
        catch (NullPointerException nil) { Log.d(TAG, "encodeImage:"+nil); return  false; }
        return true;

    }

    public void finishEncoding(){
        try { encoder.finish(); }
        catch (IOException io) {
            Log.d("DDVideoEncoder", "IOException"); }
    }

    // newSize indicates size of bitmap in percent of original.
    //decodes image and scales it to reduce memory consumption
    private Bitmap getResizedBitmap(String filePath, int newSize) {

        //Decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        //BitmapFactory.decodeStream(new FileInputStream(f),null,o);
        BitmapFactory.decodeFile(filePath, o);

        //The new size we want to scale to
        final int REQUIRED_SIZE=newSize*10;

        //Find the correct scale value. It should be the power of 2.
        int scale=1;
        while(o.outWidth/scale/2>=REQUIRED_SIZE && o.outHeight/scale/2>=REQUIRED_SIZE)
            scale*=2;

        //Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize=scale;
        //return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
        return BitmapFactory.decodeFile(filePath, o2);
    }
}

And you can then use the class like this:

try {
    DDVideoEncoder tmpEncoder = new DDVideoEncoder(dir+vidName);

    // write x frames
    Log.d("test", "adding frame");

    try { tmpEncoder.addFrame(path, 50); }
    catch (OutOfMemoryError outOfMemoryError){  Log.d("test", "oom");  break; }
    catch (IOException io) { Log.d("CactusMemChecker", io.getMessage());  break; }
    catch (IndexOutOfBoundsException oob) { Log.d("test", "oob");  break; }

    // finish up
    tmpEncoder.finishEncoding();

} catch (IOException e) { 
    Log.d("test", e.getMessage()); 
    testResult = false; 
} catch (OutOfMemoryError e) { 
    Log.d("test", e.getMessage()); 
    testResult = false; 
} catch (IndexOutOfBoundsException e) { 
    Log.d("test", e.getMessage()); 
    testResult = false; 
}

How to change video resolution with jcodec

1 Answers1