ImageIO.read() returns null if the input image type is not supported (which occurs when trying to read a PPM file), so output a friendly error instead of letting the next line throw a null pointer exception.
ImageIO.read() returns null if the input image type is not supported (which occurs when trying to read a PPM file), so output a friendly error instead of letting the next line throw a null pointer exception.



billychappell/mozjpeg,zhoujianhanyu/mozjpeg,zhoujianhanyu/mozjpeg,bygreencn/mozjpeg,ekandrot/mozjpeg,zhoujianhanyu/mozjpeg,zhoujianhanyu/mozjpeg,billychappell/mozjpeg,zhoujianhanyu/mozjpeg,ekandrot/mozjpeg,m-2k/mozjpeg,bygreencn/mozjpeg,ekandrot/mozjpeg,m-2k/mozjpeg,bygreencn/mozjpeg,m-2k/mozjpeg,ekandrot/mozjpeg,bygreencn/mozjpeg,bygreencn/mozjpeg,ekandrot/mozjpeg,billychappell/mozjpeg,billychappell/mozjpeg,m-2k/mozjpeg,m-2k/mozjpeg,billychappell/mozjpeg