How to modify rgb pixel of an bitmap to look diffe

2019-01-15 22:27发布

问题:

I am trying to convert a bitmap image to look like captured in thermal or night.

But i have no idea what/how to modify the pixels to look like that. I only know

public static Bitmap newBitmapwithNightOrThermalEffect(Bitmap bmp) {
        long start = System.currentTimeMillis();
        int width = bmp.getWidth();
        int height = bmp.getHeight();
        Bitmap bitmap = Bitmap.createBitmap(width, height,
                Bitmap.Config.RGB_565);
        int pixColor = 0;
        int pixR = 0;
        int pixG = 0;
        int pixB = 0;
        int newR = 0;
        int newG = 0;
        int newB = 0;
        int[] pixels = new int[width * height];
        bmp.getPixels(pixels, 0, width, 0, 0, width, height);
        for (int i = 0; i < height; i++) {
            for (int k = 0; k < width; k++) {
                pixColor = pixels[width * i + k];
                pixR = Color.red(pixColor);
                pixG = Color.green(pixColor);
                pixB = Color.blue(pixColor);

        //how can i modify newR,newG and newB to look like night or thermal


                newR = (int) (0.393 * pixR + 0.769 * pixG + 0.189 * pixB);  
                newG = (int) (0.349 * pixR + 0.686 * pixG + 0.168 * pixB);
                newB = (int) (0.272 * pixR + 0.534 * pixG + 0.131 * pixB);
                int newColor = Color.argb(255, newR > 255 ? 255 : newR,
                        newG > 255 ? 255 : newG, newB > 255 ? 255 : newB);
                pixels[width * i + k] = newColor;
            }
        }

        bitmap.setPixels(pixels, 0, width, 0, 0, width, height);
        long end = System.currentTimeMillis();
        Log.d("may", "used time=" + (end - start));
        return bitmap;
    }

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