Android 圖片的顏色處理

仿造美圖秀秀移動滑鼠調整seekbar，調整圖片的顏色

項目佈局如下：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity" >

    <SeekBar
        android:id="@+id/sb1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:max="255" />

    <SeekBar
        android:id="@+id/sb2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:max="255" />

    <SeekBar
        android:id="@+id/sb3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:max="255" />

    <ImageView
        android:id="@+id/iv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</LinearLayout>

效果如下：

邏輯部分代碼如下：

package com.wuyudong.resize;

import android.os.Bundle;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.view.Menu;
import android.widget.ImageView;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;

public class MainActivity extends Activity {

    private ImageView iv1;
    private SeekBar sb1, sb2, sb3;
    
    private Bitmap alterBitmap;
    private Canvas canvas;
    private Paint paint;

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

        iv1 = (ImageView) findViewById(R.id.iv);

        // 設置第一個bitmap的圖標
        final Bitmap bitmap1 = BitmapFactory.decodeResource(getResources(),
                R.drawable.ic_launcher);

        // 新建一個bitmap
        alterBitmap = Bitmap.createBitmap(bitmap1.getWidth(),
                bitmap1.getHeight(), bitmap1.getConfig());

        // 以alterBitmap為模板新建畫布
        canvas = new Canvas(alterBitmap);
        // 新建畫筆並設置屬性
        paint = new Paint();
        paint.setColor(Color.BLACK);

        // 新建矩陣
        final Matrix matrix = new Matrix();

        // 指定顏色矩陣
        final ColorMatrix cm = new ColorMatrix();
        
        /**
         * Set this colormatrix to identity:
         * [ 1 0 0 0 0   - red vector
         *   0 1 0 0 0   - green vector
         *   0 0 1 0 0   - blue vector
         *   0 0 0 1 0 ] - alpha vector
         */
        paint.setColorFilter(new ColorMatrixColorFilter(cm));

        paint.setAntiAlias(true);

        // 設置畫布
        canvas.drawBitmap(bitmap1, matrix, paint);
        iv1.setImageBitmap(alterBitmap);

        sb1 = (SeekBar) findViewById(R.id.sb1);
        sb2 = (SeekBar) findViewById(R.id.sb2);
        sb3 = (SeekBar) findViewById(R.id.sb3);

        sb1.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                int progress = seekBar.getProgress();
                cm.set(new float[]{
                        progress/128.0f, 0, 0, 0, 0,
                        0, 1, 0, 0, 0,
                        0, 0, 1, 0, 0,
                        0, 0, 0, 1, 0,
                });
                paint.setColorFilter(new ColorMatrixColorFilter(cm));
                canvas.drawBitmap(bitmap1, matrix, paint);
                iv1.setImageBitmap(alterBitmap);
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onProgressChanged(SeekBar seekBar, int progress,
                    boolean fromUser) {

            }
        });
        sb2.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                int progress = seekBar.getProgress();
                cm.set(new float[]{
                        progress/128.0f, 0, 0, 0, 0,
                        0, 1, 0, 0, 0,
                        0, 0, progress/128.0f, 0, 0,
                        0, 0, 0, 1, 0,
                });
                paint.setColorFilter(new ColorMatrixColorFilter(cm));
                canvas.drawBitmap(bitmap1, matrix, paint);
                iv1.setImageBitmap(alterBitmap);
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onProgressChanged(SeekBar seekBar, int progress,
                    boolean fromUser) {

            }
        });
        sb3.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
                int progress = seekBar.getProgress();
                cm.set(new float[]{
                        1, 0, 0, 0, 0,
                        0, 1, 0, 0, 0,
                        0, 0, progress/128.0f, 0, 0,
                        0, 0, 0, 1, 0,
                });
                paint.setColorFilter(new ColorMatrixColorFilter(cm));
                canvas.drawBitmap(bitmap1, matrix, paint);
                iv1.setImageBitmap(alterBitmap);
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onProgressChanged(SeekBar seekBar, int progress,
                    boolean fromUser) {

            }
        });
    }

}

運行效果：