Run Jar File From Batch File And CMD Manually

I get the following error when I try to run my jar file from a Batch file and CMD manually (The batch file is just set to run the jar and record any output to a text file, and open it after).

Exception in thread "main" java.lang.IllegalArgumentException: input == null!
at javax.imageio.ImageIO.read(Unknown Source)
at com.github.bewd.project.main.Main.<init>(Main.java:37)
at com.github.bewd.project.main.Main.main(Main.java:76)

However running from Netbeans, it works perfectly; JFrame and all. I'm not sure if it's something wrong with my classpath (which I don't think is likely) or something in my code that's affecting it, here's the code:

import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.math.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import java.util.Scanner;
import java.util.logging.Logger;
import javax.imageio.ImageIO;

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