Android - 使用opencv读取图像

Question

我尝试从 drawable 文件夹中读取图片。我正在使用 eclipse ide。我运行下面的代码，但没有加载图像。代码取自here

Mat image =  new Mat(new Size(500,500 ),CvType.CV_8U);// Change CvType as you need.
            image = Highgui.imread("icon.png");
            if(image.empty()) {
                Log.i(TAG, "Empty image!");
            }

我 我的drawable文件夹的屏幕截图如下：

如何加载此图片？

Answer 1

你可以简单地做到这一点

Mat m = Utils.loadResource(MainActivity.this, R.drawable.img, Imgcodecs.CV_LOAD_IMAGE_GRAYSCALE);
Bitmap bm = Bitmap.createBitmap(m.cols(), m.rows(),Bitmap.Config.ARGB_8888);
Utils.matToBitmap(m, bm);
ImageView iv = (ImageView) findViewById(R.id.imageView1);
iv.setImageBitmap(bm);

Answer 2

我找到了这项工作的一个例子。

InputStream inpT = getResources().openRawResource(R.drawable.imgt);
mTemp = readInputStreamIntoMat(inpT);

private static Mat readInputStreamIntoMat(InputStream inputStream) throws IOException {
    // Read into byte-array
    byte[] temporaryImageInMemory = readStream(inputStream);

    // Decode into mat. Use any IMREAD_ option that describes your image appropriately
    Mat outputImage = Highgui.imdecode(new MatOfByte(temporaryImageInMemory), Highgui.IMREAD_GRAYSCALE);

    return outputImage;
}

private static byte[] readStream(InputStream stream) throws IOException {
    // Copy content of the image to byte-array
    ByteArrayOutputStream buffer = new ByteArrayOutputStream();
    int nRead;
    byte[] data = new byte[16384];

    while ((nRead = stream.read(data, 0, data.length)) != -1) {
        buffer.write(data, 0, nRead);
    }

    buffer.flush();
    byte[] temporaryImageInMemory = buffer.toByteArray();
    buffer.close();
    stream.close();
    return temporaryImageInMemory;
}

Answer 3

应该做的是：

  Mat m = Highgui.imread(file.getAbsolutePath());