FFMPEG in Java (runtime error)

Question

I want to write a program that converts video into frames using FFMPEG. When I use it on the Ubuntu terminal, it works fine. But when I try to put it into the Java code, it gives me a runtime error. Did I make a mistake in my code below?

import java.util.*;
import java.awt.*;
import java.lang.*;
import java.lang.Runtime;
import java.io.*;
import java.io.IOException;

public class ConvertVideoToImage
{
    private SingletonServer ss = null;

    public ConvertVideoToImage(SingletonServer ss)
    {
        this.ss = ss;
    }

    public void run()
    {
        convertVideo();
    }

    public void convertVideo()
    {
        try
        {
            Runtime rt = Runtime.getRunTime().exec("ffmpeg" + "-i" +         "display.wmv" + "image%d.jpg");
        }
        catch(Exception e){}
    }

}

I have changed the code like you suggested, but it also doesn't work. And when I Googled it, I found out that someone put the full path inside the executable and it became like this:

Runtime.getRuntime().exec("/home/pc3/Documents/ffmpeg_temp/ffmpeg -i display.wmv image%d.jpg")

BTW, thanks for the reply. I have another question. Is it possible to make a counter for FFMPEG? I used this command in the Ubuntu terminal to make it convert a video to 30 frames/1seconds:

ffmpeg -i display.wmv image%d.jpg

This will automatically generate numbers like image1.jpg, image2.jpg, to image901.jpg. Is it possible to make a counter for this? Because I need to count the files and control the number.

Thanks in advance.

Answer 1

When you call exec , you should not specify the parameters in the command string, instead, pass them in an array as second parameter.

Process p = Runtime.getRunTime().exec("ffmpeg",
               new String[]{"-i", "display.wmv", "image%d.jpg"));
//                        are you sure regarding this %^