图片处理专题

刺骨的言语ヽ痛彻心扉 2021-09-26 00:56 324阅读 0赞

1、图片太大出现内存溢出，或者图片的尺寸超出屏幕的范围，则将图片进行等比例缩放  
其中可以固定缩放比例，也可以根据屏幕大小自适应 代码：//1\_resize\_image

public class DemoActivity extends Activity { 
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            ImageView iv = (ImageView) this.findViewById(R.id.iv);
    // BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();
    // //按1/8的大小加载到内存 
    // bmpFactoryOptions.inSampleSize = 8;
    // Bitmap bm = BitmapFactory.decodeFile("/sdcard/img.jpg",bmpFactoryOptions);
    // iv.setImageBitmap(bm);
    
            // 40kb 豆瓣
    
            // 
            //1. 首先得到屏幕的宽高
            Display currentDisplay = getWindowManager().getDefaultDisplay();
            int dw = currentDisplay.getWidth();
            int dh = currentDisplay.getHeight();
            // 2. 获取图片的宽度和高度 
            BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();
            // 设置inJustDecodeBounds = true ;
            bmpFactoryOptions.inJustDecodeBounds = true;
            // 不会真正的解析这个位图 
            Bitmap bmp = BitmapFactory.decodeFile("/sdcard/img.jpg", bmpFactoryOptions);
            //得到图片的宽度和高度 
            int heightRatio = (int)Math.ceil(bmpFactoryOptions.outHeight/(float)dh);
            int widthRatio = (int)Math.ceil(bmpFactoryOptions.outWidth/(float)dw);
            Log.v("HEIGHTRATIO",""+heightRatio);
            Log.v("WIDTHRATIO",""+widthRatio);
    
            //真正的解析位图 
            bmpFactoryOptions.inJustDecodeBounds = false;
    
            if(heightRatio>widthRatio){
                bmpFactoryOptions.inSampleSize = heightRatio;
            }else{
                bmpFactoryOptions.inSampleSize = widthRatio;
            }
            bmp = BitmapFactory.decodeFile("/sdcard/img.jpg", bmpFactoryOptions);
    
            iv.setImageBitmap(bmp);
        }
    }

2、获取图片的相关信息，包括拍摄时间、地点等，并且可以重新设置信息 代码：//2\_exif\_image

public class DemoActivity extends Activity { 
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
    
            try {
                ExifInterface  exif = new ExifInterface("sdcard/img.jpg");
                //如果该信息不存在，会报错
    // System.out.println( exif.getAttribute("ImageDescription"));
                System.out.println( exif.getAttribute(ExifInterface.TAG_DATETIME));
                System.out.println( exif.getAttribute(ExifInterface.TAG_IMAGE_LENGTH));
                System.out.println( exif.getAttribute(ExifInterface.TAG_IMAGE_WIDTH));
    
                //重新设置信息
                exif.setAttribute("camera", "柯达相机");
    
                System.out.println( exif.getAttribute("camera"));
    
    
            } catch (Exception e) {
                e.printStackTrace();
            }
    
    
        }
    }

3、从手机图库选择图片上传，显示到界面中

public class DemoActivity extends Activity { 
        ImageView iv;
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            iv = (ImageView) this.findViewById(R.id.iv);
        }
    
        public void click(View view){
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            startActivityForResult(intent, 0);
    
    
        }
    
        @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {
            if(data!=null){
                //图片的uri
                Uri uri = data.getData() ;
                iv.setImageURI(uri);
            }
            super.onActivityResult(requestCode, resultCode, data);
        }

4、复制图片，并进行缩放、旋转

public class DemoActivity extends Activity { 
    
        ImageView iv1;
        ImageView iv2;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            iv1= (ImageView) this.findViewById(R.id.iv1);
            iv2= (ImageView) this.findViewById(R.id.iv2);
        }
    
    
        public void click(View view){
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            startActivityForResult(intent, 0);
        }
        @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {
            if(data!=null){
                //图片的uri
                Uri uri = data.getData() ;
                iv1.setImageURI(uri);
                // 获取第一个图片 的拷贝 设置到iv2的控件里面 
                try {
                    Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(uri));
                    Matrix matrix = new Matrix();
    // matrix.setValues(new float[] { 
    // 2, 0, 0,
    // 0, 1, 0,
    // 0, 0, 1
    // });
    // matrix.setScale(1.5f, 1.0f);
    // matrix.setRotate(30);
    
                    //创建画笔
                    Paint paint = new Paint();
                    //消除锯齿
                    paint.setAntiAlias(true);
                    matrix.setRotate(15);
                    //得到一个大小 配置跟原图一样的空的位图 
                    //Bitmap alterbitmap = Bitmap.createBitmap(bitmap.getWidth()*2, bitmap.getHeight(), bitmap.getConfig());
                    Bitmap  alteredBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(),
                            matrix, false);
    
    
                    //创建画布
                    Canvas canvas = new Canvas();
    
    
    
                    canvas.drawBitmap(bitmap, matrix, paint);
    
                    iv2.setImageBitmap(alteredBitmap);
    
                } catch (Exception e) {
                    e.printStackTrace();
                }
    
    
            }
            super.onActivityResult(requestCode, resultCode, data);
        }
    }

5、图片合成，并保存到手机

public class DemoActivity extends Activity { 
       Bitmap basebitmap;
       Canvas canvas ;
       Paint paint;
       ImageView iv;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            iv = (ImageView) this.findViewById(R.id.iv);
        }
        public void select1(View view){
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            startActivityForResult(intent, 10);
            // 从图库里面获取第一个图片 
    
    
        }
        public void save(View view){
    
            //设置用户权限以及sd卡权限
            File file = new File("/sdcard/1.jpg");
            FileOutputStream fos;
            try {
                fos = new FileOutputStream(file);
    
                basebitmap.compress(CompressFormat.JPEG, 100, fos);
                //显示的发送一条广播 
                //sd卡挂载的广播 
                Intent intent = new Intent(Intent.ACTION_MEDIA_MOUNTED,Uri.parse("file://"+Environment.getExternalStorageDirectory()));
                sendBroadcast(intent);
    
    
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    
        public void select2(View view){
            Intent intent = new Intent(Intent.ACTION_PICK);
            intent.setType("image/*");
            startActivityForResult(intent, 20);
            // 从图库里面获取第一个图片 
        }
        @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {
            if(requestCode==10){
                if(data!=null){
                    Uri uri = data.getData();
                    try {
                        Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(uri));
    
                        basebitmap = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), bitmap.getConfig());
                        canvas = new Canvas(basebitmap);
                        paint = new Paint();
                        canvas.drawBitmap(bitmap, 0, 0, paint);
    
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }else if(requestCode==20){
                if(data!=null){
                    Uri uri = data.getData();
                    //把第二张位图的内容 画在 basebitmap上 
                    try {
                        Bitmap bitmap = BitmapFactory.decodeStream(  getContentResolver().openInputStream(uri));
                        paint.setXfermode(new PorterDuffXfermode(android.graphics.PorterDuff.Mode.MULTIPLY));
                        canvas.drawBitmap(bitmap, 0,0, paint);
                        iv.setImageBitmap(basebitmap);
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
    
                }
            }
            super.onActivityResult(requestCode, resultCode, data);
        }
    
    
    
    }

6、绘制图案，并保存到手机

public class DemoActivity extends Activity { 
        ImageView iv;
        Bitmap bitmap;
        Canvas canvas;
        Paint paint;
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            iv = (ImageView) this.findViewById(R.id.iv);
            Display diaplay = getWindow().getWindowManager().getDefaultDisplay();
            int height = diaplay.getHeight() - 40;
            int width = diaplay.getWidth();
            bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
            iv.setImageBitmap(bitmap);
            canvas = new Canvas(bitmap);
            paint= new Paint();
            paint.setColor(Color.GREEN);
            paint.setStrokeWidth(10);
            iv.setOnTouchListener(new OnTouchListener() {
    
                float startx = 0;
                float starty = 0;
    
                @Override
                public boolean onTouch(View v, MotionEvent event) {
                    switch (event.getAction()) {
                    case MotionEvent.ACTION_DOWN:
                        startx =  event.getX();
                        starty =  event.getY();
    
                        break;
                    case MotionEvent.ACTION_MOVE:
                        float x =  event.getX();
                        float y =  event.getY();
                        canvas.drawLine(startx, starty, x, y, paint);
                        startx =  event.getX();
                        starty =  event.getY();
    
                        //通知imageview更新界面 
                        iv.invalidate();
                        break;
                    case MotionEvent.ACTION_UP:
                        float endx =  event.getX();
                        float endy =  event.getY();
                        canvas.drawLine(startx, starty, endx, endy, paint);
                        //通知imageview更新界面 
                        iv.invalidate();
                        break;
                    default:
                        break;
                    }
    
                    return true;
                }
            });
    
        }
    
        public void save(View view) {
            File file = new File("/sdcard/"+System.currentTimeMillis()+".jpg");
            FileOutputStream fos;
            try {
                fos = new FileOutputStream(file);
    
                bitmap.compress(CompressFormat.JPEG, 100, fos);
                //显示的发送一条广播 
                //sd卡挂载的广播 
                Intent intent = new Intent(Intent.ACTION_MEDIA_MOUNTED,Uri.parse("file://"+Environment.getExternalStorageDirectory()));
                sendBroadcast(intent);
    
    
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

7、人脸识别，并在脸部画圆圈

public class DemoActivity extends Activity { 
        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            InputStream is = getResources().openRawResource(R.raw.qq);
            Bitmap faceBitmap = BitmapFactory.decodeStream(is);
            Face[] mFaces = new Face[3];
            FaceDetector detector = new FaceDetector(faceBitmap.getWidth(),
                    faceBitmap.getHeight(), 3); // 创建识别器
            int mNumFaces = detector.findFaces(faceBitmap, mFaces);
            System.out.println(mNumFaces);
            if (mNumFaces > 0) {
    
                Bitmap alterbitmap = Bitmap.createBitmap(faceBitmap.getWidth(),
                        faceBitmap.getHeight(), faceBitmap.getConfig());
                Canvas canvas = new Canvas(alterbitmap);
                Paint paint = new Paint();
                canvas.drawBitmap(faceBitmap, 0, 0, paint);
    
                PointF midPoint = new PointF();
                int r = ((int) (mFaces[0].eyesDistance() * 1.5)); // 取眼睛间距离
                mFaces[0].getMidPoint(midPoint); // 取脸的中点
                Paint p = new Paint();
                p.setColor(Color.GREEN);
                p.setAntiAlias(true);
                p.setAlpha(0x80);
                canvas.drawCircle(midPoint.x, midPoint.y, r, p); // 用半透明标出人脸区域;
    
                ImageView iv = new ImageView(this);
                iv.setImageBitmap(alterbitmap);
                setContentView(iv);
            }
    
        }
    }