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Include FFMpeg in Android and grab a frame from a 3gp video.

Thought I would write about the recent pain I experienced in trying to get FFMpeg into Android and subsequently grab a frame from a video. Hopefully this tutorial will help out a bunch of people, so anyway here we go.

The first thing you are going to want to get is JavaCV (Website here) and follow the EXACT instructions under "Quick Start for OpenCV"

If you followed the instructions you should have 2 jar files in your build path along with a large amount of .so files in your libs/armeabi folder. Now the class you are going to be looking at is called "FFMpegFrameGrabber" (Code here). Here is some sample code to give you a general idea of how to grab a frame from your video.

//Path is the path to your .3gp or whatever file on your sdcard
FrameGrabber f = new FFMpegFrameGrabber(path);
f.start();
IplImage _image = f.grab();
//We need to convert from 3 channels to 4 channels so that we can convert
//from IplImage to Bitmap
IplImage image = IplImage.create(return_image.width() ,return_image.height(),IPL_DEPTH_8U,4);
//source, dest, code
cvCvtColor(_image,image,CV_BGR2RGBA);
int width = image.width();
int height = image.height();
Bitmap b = Bitmap.createBitmap(width,height, Config.ARGB_8888);
//Make sure you use getByteBuffer()!
b.copyPixelsFromBuffer(image.getByteBuffer());
//MAKE SURE YOU DO NOT CALL stop() BEFORE YOU CREATE A BITMAP FROM IMAGE
f.stop();

You might see an error about cvCvtColor, in which case you need to add the following in your import statements:

import static com.googlecode.javacv.cpp.opencv_imgproc.*;

Now you can display your new bitmap in whichever way you want.