通过使用Android的Camera API和ColorMatrix类,可以将YUV格式转换为RGB格式,从而在屏幕上显示颜色图像。以下是一个简单的示例代码,显示了如何使用ColorMatrix类进行转换:
private void processImage(byte[] data) {
int[] colors = new int[previewSize.width * previewSize.height];
YuvImage yuv = new YuvImage(data, ImageFormat.NV21, previewSize.width, previewSize.height, null);
ByteArrayOutputStream out = new ByteArrayOutputStream();
yuv.compressToJpeg(new Rect(0, 0, previewSize.width, previewSize.height), 100, out);
byte[] bytes = out.toByteArray();
Bitmap bitmap = BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
ColorMatrix yuvToRgb = new ColorMatrix(new float[] {
1, 0, 0, 0, 0,
0, 1, 0, 0, 0,
0, 0, 1, 0, 0,
0, 0, 0, 1, 0
});
ColorMatrix rgbToHsv = new ColorMatrix(new float[] {
0.213f, 0.715f, 0.072f, 0,
0.213f, 0.715f, 0.072f, 0,
0.213f, 0.715f, 0.072f, 0,
0, 0, 0, 1
});
ColorMatrix colorMatrix = new ColorMatrix();
colorMatrix.postConcat(yuvToRgb);
colorMatrix.postConcat(rgbToHsv);
Paint paint = new Paint();
ColorFilter filter = new ColorMatrixColorFilter(colorMatrix);
paint.setColorFilter(filter);
Canvas canvas = new Canvas(bitmap);
canvas.drawBitmap(bitmap, 0, 0, paint);
// do something with the colored bitmap
}
在上面的示例中,我们首先将YUV图像数据转换为JPEG格式,然后通过BitmapFactory类将其解码为Bitmap对象。接下来,我们使用两个ColorMatrix来将RGB图像转换为HSV格式,然后将它们组合成一个单独的ColorMatrix。最后,我们使用Paint和Canvas类来将ColorMatrix应用于Bitmap并在屏幕上显示结果。