Reproducing encrypted video using ExoPlayer

Question

I\'m using ExoPlayer, in Android, and I\'m trying to reproduce an encrypted video stored locally.

The modularity of ExoPlayer allows to create custom components tha

Answer 1

Eventually I found the solution.

I used a no-padding for the encryption algorithm, in this way:

cipher = Cipher.getInstance("AES/CTR/NoPadding", "BC");

so that the size of the encrypted file and the clear file size remain the same. So now I created the stream:

cipherInputStream = new CipherInputStream(inputStream, cipher) {
    @Override
    public int available() throws IOException {
         return in.available();
    }
};

This is because the Java documentation says about ChiperInputStream.available() that

This method should be overriden

and actually I think is it more like a MUST, because the values retrieved from that method are often really strange.

And that is it! Now it works perfectly.