【Android】使用SeekBar调整图像的色度、饱和及度亮度

SeekBar通过滑块位置来标识数值，且允许用户拖动滑块来改变值。下面利用三条SeeKBar来调整图片的色度（Hue）、饱和度（Saturation）、亮度（Lum）。

布局文件为一个ImageView，三条SeekBar，布局简单，在此省略。

首先创建一个图像处理类ImageHelper:

public class ImageHelper {
    public static Bitmap handleImage(Bitmap bmp, float hue, float saturation, float lum){
        Bitmap bm = Bitmap.createBitmap(bmp.getWidth(),bmp.getHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bm);
        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);


        ColorMatrix hueMatrix = new ColorMatrix();
        hueMatrix.setRotate(0,hue);
        hueMatrix.setRotate(1,hue);
        hueMatrix.setRotate(2,hue);


        ColorMatrix satMatrix = new ColorMatrix();
        satMatrix.setSaturation(saturation);


        ColorMatrix lumMatrix = new ColorMatrix();
        lumMatrix.setScale(lum,lum,lum,1); //涓変釜閫氶亾鍜岄�忔槑搴�


        ColorMatrix imgMatrix = new ColorMatrix(); //涓変釜ColorMatrix杩涜铻嶅悎
        imgMatrix.postConcat(hueMatrix);
        imgMatrix.postConcat(satMatrix);
        imgMatrix.postConcat(lumMatrix);


        paint.setColorFilter(new ColorMatrixColorFilter(imgMatrix));
        canvas.drawBitmap(bmp,0,0,paint);
        return bm;
    }
}

下面是MainActivity中的处理：

/**
	 * Created by dell on 2016/1/10.
	 */
	public class MainActivity extends Activity implements SeekBar.OnSeekBarChangeListener {
	    private TextView textView;
	    private SeekBar hue_bar, sat_bar, lum_bar;
	    private Button cancel_btn, ok_btn;
	    private ImageView hsl_img;
	    private static int MAX_VALUE = 255;
	    private static int MID_VALUE = 127;
	    private float mHue, mSaturation, mLum;
	    private Bitmap bitmap;

	    @Override
	    protected void onCreate(Bundle savedInstanceState) {
	        super.onCreate(savedInstanceState);
	        setContentView(R.layout.activity_main);

	        initViews();
	    }

	    private void initViews() {
	    	bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.lin);
	        textView = (TextView) findViewById(R.id.textView);
	        hue_bar = (SeekBar) findViewById(R.id.seekBar_h);
	        sat_bar = (SeekBar) findViewById(R.id.seekBar_s);
	        lum_bar = (SeekBar) findViewById(R.id.seekBar_l);
	        hsl_img = (ImageView) findViewById(R.id.hsl_img);

	        hue_bar.setOnSeekBarChangeListener(this);
	        sat_bar.setOnSeekBarChangeListener(this);
	        lum_bar.setOnSeekBarChangeListener(this);

	        hue_bar.setMax(MAX_VALUE); //设置最大值
	        sat_bar.setMax(MAX_VALUE);
	        lum_bar.setMax(MAX_VALUE);

	        hue_bar.setProgress(MID_VALUE); //设置初始值
	        sat_bar.setProgress(MID_VALUE);
	        lum_bar.setProgress(MID_VALUE);
	        
	        
	        hsl_img.setImageBitmap(bitmap);
	       
	    }


	    @Override
	    public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
	        switch (seekBar.getId()){
	            case R.id.seekBar_h:
	                mHue = (progress - MID_VALUE) * 1.0F / MID_VALUE * 180;
	                break;
	            case R.id.seekBar_s:
	                mSaturation = progress * 1.0F / MID_VALUE;
	                break;
	            case R.id.seekBar_l:
	                mLum = progress * 1.0F / MID_VALUE;
	                break;
	        }
	        hsl_img.setImageBitmap(ImageHelper.handleImage(bitmap,mHue,mSaturation,mLum));
	    }

	    @Override
	    public void onStartTrackingTouch(SeekBar seekBar) {

	    }

	    @Override
	    public void onStopTrackingTouch(SeekBar seekBar) {

	    }
	}

SeekBar需要绑定的是 setOnSeekBarChangeListener来实现对拖动位置的改变，里面有三个方法，主要需要重写的是

void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser)

progress代表监测到的当前滑动位置。

最后，附上实验效果，打开界面，并进行调节：