我想转换图片使用java和opencv从rgb到灰色
所有的图像都正常工作，我用灰色图像，
如果我制作.gif图像（不移动），则会出现以下错误： OpenCV Error: Assertion failed (scn == 3 || scn == 4) in cv::cvtColor java代码：

Mat scrImg = Highgui.imread(path);
Mat dstImg = new Mat(scrImg.rows(),scrImg.cols(),scrImg.type());
Imgproc.cvtColor(scrImg, dstImg, Imgproc.COLOR_RGB2GRAY);

private static BufferedImage Mat2BufferedImage(Mat matrix){
	BufferedImage bimOut;
	int type;
	if(matrix.channels() == 1)
		type = BufferedImage.TYPE_BYTE_GRAY;

	else 
		type = BufferedImage.TYPE_3BYTE_BGR;

	int dataLength = matrix.channels()*matrix.cols()*matrix.rows();
	byte [] buffer = new byte[dataLength];
	bimOut = new BufferedImage(matrix.cols(),matrix.rows(),type);
	matrix.get(0,0,buffer);
	final byte[] bimPixels = ((DataBufferByte) bimOut.getRaster().getDataBuffer()).getData();
	System.arraycopy(buffer, 0, bimPixels, 0, buffer.length);

	return bimOut;

}