How to implement freehand image cropping in android?
I have tried lots of solution for this problem in my project, but this code is working. Here, i put my own project's Code Here. You can use it, if you found your solution in it.
public class CropView extends View implements View.OnTouchListener {
public static final String INTENT_KEY_CROP = "crop";
public static final String CACHE_KEY = "bitmap";
public static List<Point> points;
boolean flgPathDraw = true;
boolean bFirstPoint = false;
private Point firstPoint = null;
private Point lastPoint = null;
private final Bitmap originalImageBitmap;
private int canvasWidth;
private int canvasHeight;
private Paint paint;
private Context context;
private static LruCache<String, Bitmap> mMemoryCache;
private final ImageCropListener imageCropListener;
public interface ImageCropListener {
void onClickDialogPositiveButton();
void onClickDialogNegativeButton();
}
public static Bitmap getBitmapFromMemCache() {
return mMemoryCache.get(CACHE_KEY);
}
public CropView(Context c, Bitmap bm, ImageCropListener listener) {
super(c);
context = c;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setPathEffect(new DashPathEffect(new float[] { 10, 20 }, 0));
paint.setStrokeWidth(5);
paint.setColor(Color.WHITE);
this.setOnTouchListener(this);
points = new ArrayList<>();
bFirstPoint = false;
this.originalImageBitmap = bm;
this.imageCropListener = listener;
final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);
final int cacheSize = maxMemory / 8;
mMemoryCache = new LruCache<String, Bitmap>(cacheSize) {
@Override
protected int sizeOf(String key, Bitmap bitmap) {
// The cache size will be measured in kilobytes rather than
// number of items.
return bitmap.getByteCount() / 1024;
}
};
}
public CropView(Context context, AttributeSet attrs, Bitmap bm,
ImageCropListener listener) {
super(context, attrs);
this.context = context;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(2);
paint.setColor(Color.WHITE);
this.setOnTouchListener(this);
points = new ArrayList<>();
bFirstPoint = false;
this.originalImageBitmap = bm;
this.imageCropListener = listener;
}
public void addBitmapToMemoryCache(Bitmap bitmap) {
if (getBitmapFromMemCache() == null) {
mMemoryCache.put(CACHE_KEY, bitmap);
}
}
private float calcBitmapScale(int canvasWidth, int canvasHeight, int bmpWidth, int bmpHeight) {
float scale = (float)canvasWidth / (float)bmpWidth;
float tmp = bmpHeight * scale;
if (tmp < canvasHeight) {
scale = (float)canvasHeight / (float)bmpHeight;
return scale;
}
return scale;
}
public void onDraw(Canvas canvas) {
canvasWidth = canvas.getWidth();
canvasHeight = canvas.getHeight();
/* int bmpWidth = this.originalImageBitmap.getWidth();
int bmpHeight = this.originalImageBitmap.getHeight();
float toCanvasScale = this.calcBitmapScale(canvasWidth, canvasHeight, bmpWidth, bmpHeight);
float diffX = (bmpWidth * toCanvasScale - canvasWidth);
float diffY = (bmpHeight * toCanvasScale - canvasHeight);
float addX = (diffX / toCanvasScale) / 2;
float addY = (diffY / toCanvasScale) / 2;
Rect rSrc = new Rect((int)addX, (int)addY,
(int)((canvasWidth / toCanvasScale) + addX), (int)((canvasHeight /
toCanvasScale) + addY));
RectF rDest = new RectF(0, 0, canvasWidth, canvasHeight);
*/
canvas.drawBitmap(originalImageBitmap, 0, 0, null);
Path cropAreaPath = new Path();
boolean isFirstPoint = true;
for (int i = 0; i < points.size(); i += 2) {
Point point = points.get(i);
if (isFirstPoint) {
isFirstPoint = false;
// 最初の処理でPathのx,y座標をpointの座標に移動する
cropAreaPath.moveTo(point.x, point.y);
} else if (i < points.size() - 1) {
Point next = points.get(i + 1);
cropAreaPath.quadTo(point.x, point.y, next.x, next.y);
} else {
lastPoint = points.get(i);
cropAreaPath.lineTo(point.x, point.y);
}
}
canvas.drawPath(cropAreaPath, paint);
}
public boolean onTouch(View view, MotionEvent event) {
Point point = new Point();
point.x = (int) event.getX();
point.y = (int) event.getY();
if (flgPathDraw) {
if (bFirstPoint) {
if (comparePoint(firstPoint, point)) {
// points.add(point);
points.add(firstPoint);
flgPathDraw = false;
showCropDialog();
} else {
points.add(point);
}
} else {
points.add(point);
}
if (!(bFirstPoint)) {
firstPoint = point;
bFirstPoint = true;
}
}
invalidate();
//Log.e("Hi ==>", "Size: " + point.x + " " + point.y);
if (event.getAction() == MotionEvent.ACTION_UP) {
Log.d("Action up***>", "called");
lastPoint = point;
if (flgPathDraw) {
if (points.size() > 12) {
if (!comparePoint(firstPoint, lastPoint)) {
flgPathDraw = false;
points.add(firstPoint);
showCropDialog();
}
}
}
}
return true;
}
private boolean comparePoint(Point first, Point current) {
int left_range_x = (int) (current.x - 3);
int left_range_y = (int) (current.y - 3);
int right_range_x = (int) (current.x + 3);
int right_range_y = (int) (current.y + 3);
if ((left_range_x < first.x && first.x < right_range_x)
&& (left_range_y < first.y && first.y < right_range_y)) {
if (points.size() < 10) {
return false;
} else {
return true;
}
} else {
return false;
}
}
public void fillinPartofPath() {
Point point = new Point();
point.x = points.get(0).x;
point.y = points.get(0).y;
points.add(point);
invalidate();
}
public void resetView() {
points.clear();
paint.setColor(Color.WHITE);
paint.setStyle(Paint.Style.STROKE);
flgPathDraw = true;
invalidate();
}
private void showCropDialog() {
final Bitmap croppedImage = cropImage(this.originalImageBitmap);
DialogInterface.OnClickListener dialogClickListener = new
DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
switch (which) {
case DialogInterface.BUTTON_POSITIVE:
addBitmapToMemoryCache(croppedImage);
imageCropListener.onClickDialogPositiveButton();
break;
case DialogInterface.BUTTON_NEGATIVE:
bFirstPoint = false;
resetView();
imageCropListener.onClickDialogNegativeButton();
break;
}
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setMessage("Do you Want to save Crop or Non-crop image?")
.setPositiveButton("Crop", dialogClickListener)
.setNegativeButton("Cancel", dialogClickListener).show()
.setCancelable(false);
}
private Bitmap cropImage(Bitmap image) {
Bitmap cropImage = Bitmap.createBitmap(canvasWidth, canvasHeight,
image.getConfig());
Canvas canvas = new Canvas(cropImage);
Paint paint = new Paint();
paint.setAntiAlias(true);
Path path = new Path();
for (int i = 0; i < CropView.points.size(); i++) {
path.lineTo(CropView.points.get(i).x, CropView.points.get(i).y);
}
canvas.drawPath(path, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(originalImageBitmap, 0, 0, paint);
return cropImage;
}
class Point {
public float dy;
public float dx;
float x, y;
@Override
public String toString(){
return x + ", " + y;
}
}
}
Then You can get Crop Result..as like,
Bitmap cropBitmap = CropView.getBitmapFromMemCache();
cropBitmap = getBitmapWithTransparentBG(cropBitmap,Color.WHITE);
Drawable d = new BitmapDrawable(getResources(),cropBitmap);
public Bitmap getBitmapWithTransparentBG(Bitmap srcBitmap, int bgColor) {
Bitmap result = srcBitmap.copy(Bitmap.Config.ARGB_8888, true);
int nWidth = result.getWidth();
int nHeight = result.getHeight();
for (int y = 0; y < nHeight; ++y)
for (int x = 0; x < nWidth; ++x) {
int nPixelColor = result.getPixel(x, y);
if (nPixelColor == bgColor)
result.setPixel(x, y, Color.TRANSPARENT);
}
return result;
}
I Think, This code will be perfect for your problem solution.. Thanks
In general, your code looks OK, but I have a few comments:
- Unable to set bitmap in full screen using canvas
If i set bitmap in full screen in canvas than image is stretching
The portion of the image that you are selecting needs to be placed in a smaller bitmap so the layout XML can position it as you like. You are creating a bitmap that is full screen. See the following demo for details.How to set transparent background to cropped bitmap
I am unclear about what the issue is.Unable to add border to cropped image
- The result of image Cropping is not as expected
See below.
Here is a small demo app using your code. You didn't provide an MCVE, so I threw the following together for demonstration purposes. Other than getting the app to function I think that the only change is to draw the border in MainActivity.java. The border width starts at the cut-out path that the user draws and reaches inward to the cut-out. If you want to actually frame the cutout without losing any pixels, then you will need to expand the path to accommodate the frame which I arbitrarily set to 20 pixels.
I also had to create the layouts used, so you may want to look at those. They are posted below.
Here is the demo video with the code to follow:
MainActivity.java
public class MainActivity extends AppCompatActivity {
private Bitmap mBitmap;
private SomeView mSomeView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.dog);
mSomeView = new SomeView(this, mBitmap);
LinearLayout layout = findViewById(R.id.layout);
LinearLayout.LayoutParams lp =
new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
layout.addView(mSomeView, lp);
}
public void cropImage() {
setContentView(R.layout.activity_picture_preview);
ImageView imageView = findViewById(R.id.image);
Bitmap fullScreenBitmap =
Bitmap.createBitmap(mSomeView.getWidth(), mSomeView.getHeight(), mBitmap.getConfig());
Canvas canvas = new Canvas(fullScreenBitmap);
Path path = new Path();
List<Point> points = mSomeView.getPoints();
for (int i = 0; i < points.size(); i++) {
path.lineTo(points.get(i).x, points.get(i).y);
}
// Cut out the selected portion of the image...
Paint paint = new Paint();
canvas.drawPath(path, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(mBitmap, 0, 0, paint);
// Frame the cut out portion...
paint.setColor(Color.WHITE);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(10f);
canvas.drawPath(path, paint);
// Create a bitmap with just the cropped area.
Region region = new Region();
Region clip = new Region(0, 0, fullScreenBitmap.getWidth(), fullScreenBitmap.getHeight());
region.setPath(path, clip);
Rect bounds = region.getBounds();
Bitmap croppedBitmap =
Bitmap.createBitmap(fullScreenBitmap, bounds.left, bounds.top,
bounds.width(), bounds.height());
imageView.setImageBitmap(croppedBitmap);
}
}
SomeView.java
I don't think there were any substantive changes to this class.
public class SomeView extends View implements View.OnTouchListener {
private Paint paint;
private List<Point> points;
int DIST = 2;
boolean flgPathDraw = true;
Point mfirstpoint = null;
boolean bfirstpoint = false;
Point mlastpoint = null;
Bitmap bitmap;
Context mContext;
public SomeView(Context c, Bitmap bitmap) {
super(c);
mContext = c;
this.bitmap = bitmap;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setPathEffect(new DashPathEffect(new float[]{10, 20}, 0));
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
this.setOnTouchListener(this);
points = new ArrayList<Point>();
bfirstpoint = false;
}
public SomeView(Context context, AttributeSet attrs) {
super(context, attrs);
mContext = context;
setFocusable(true);
setFocusableInTouchMode(true);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
points = new ArrayList<Point>();
bfirstpoint = false;
this.setOnTouchListener(this);
}
public void onDraw(Canvas canvas) {
/*Rect dest = new Rect(0, 0, getWidth(), getHeight());
paint.setFilterBitmap(true); canvas.drawBitmap(bitmap, null, dest, paint);*/
canvas.drawBitmap(bitmap, 0, 0, null);
Path path = new Path();
boolean first = true;
for (int i = 0; i < points.size(); i += 2) {
Point point = points.get(i);
if (first) {
first = false;
path.moveTo(point.x, point.y);
} else if (i < points.size() - 1) {
Point next = points.get(i + 1);
path.quadTo(point.x, point.y, next.x, next.y);
} else {
mlastpoint = points.get(i);
path.lineTo(point.x, point.y);
}
}
canvas.drawPath(path, paint);
}
public boolean onTouch(View view, MotionEvent event) {
// if(event.getAction() != MotionEvent.ACTION_DOWN)
// return super.onTouchEvent(event);
Point point = new Point();
point.x = (int) event.getX();
point.y = (int) event.getY();
if (flgPathDraw) {
if (bfirstpoint) {
if (comparepoint(mfirstpoint, point)) {
// points.add(point);
points.add(mfirstpoint);
flgPathDraw = false;
showcropdialog();
} else {
points.add(point);
}
} else {
points.add(point);
}
if (!(bfirstpoint)) {
mfirstpoint = point;
bfirstpoint = true;
}
}
invalidate();
Log.e("Hi ==>", "Size: " + point.x + " " + point.y);
if (event.getAction() == MotionEvent.ACTION_UP) {
Log.d("Action up*****~~>>>>", "called");
mlastpoint = point;
if (flgPathDraw) {
if (points.size() > 12) {
if (!comparepoint(mfirstpoint, mlastpoint)) {
flgPathDraw = false;
points.add(mfirstpoint);
showcropdialog();
}
}
}
}
return true;
}
private boolean comparepoint(Point first, Point current) {
int left_range_x = (int) (current.x - 3);
int left_range_y = (int) (current.y - 3);
int right_range_x = (int) (current.x + 3);
int right_range_y = (int) (current.y + 3);
if ((left_range_x < first.x && first.x < right_range_x)
&& (left_range_y < first.y && first.y < right_range_y)) {
if (points.size() < 10) {
return false;
} else {
return true;
}
} else {
return false;
}
}
public void fillinPartofPath() {
Point point = new Point();
point.x = points.get(0).x;
point.y = points.get(0).y;
points.add(point);
invalidate();
}
public void resetView() {
points.clear();
paint.setColor(Color.WHITE);
paint.setStyle(Paint.Style.STROKE);
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(5);
paint.setColor(Color.RED);
points = new ArrayList<Point>();
bfirstpoint = false;
flgPathDraw = true;
invalidate();
}
private void showcropdialog() {
DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Intent intent;
switch (which) {
case DialogInterface.BUTTON_POSITIVE:
((MainActivity) mContext).cropImage();
break;
case DialogInterface.BUTTON_NEGATIVE:
/*// No button clicked
intent = new Intent(mContext, DisplayCropActivity.class); intent.putExtra("crop", false); mContext.startActivity(intent);
bfirstpoint = false;*/ resetView();
break;
}
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(mContext);
builder.setMessage("Do you Want to save Crop or Non-crop image?")
.setPositiveButton("Crop", dialogClickListener)
.setNegativeButton("Non-crop", dialogClickListener).show()
.setCancelable(false);
}
public List<Point> getPoints() {
return points;
}
}
activity_main.xml
<LinearLayout
android:id="@+id/layout"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity"/>
activity_picture_preview.xml
<android.support.constraint.ConstraintLayout x
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/colorPrimary">
<ImageView
android:id="@+id/image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:srcCompat="@drawable/dog" />
</android.support.constraint.ConstraintLayout>
If you want to create a cropped bitmap with a 100px border, use the following code in cropImage():
// Create a bitmap with just the cropped area.
Region region = new Region();
Region clip = new Region(0, 0, fullScreenBitmap.getWidth(), fullScreenBitmap.getHeight());
region.setPath(path, clip);
Rect sourceBounds = region.getBounds();
Rect destBounds =
new Rect(CROPPED_MARGIN, CROPPED_MARGIN, sourceBounds.width() + CROPPED_MARGIN,
sourceBounds.height() + CROPPED_MARGIN);
Bitmap croppedBitmap =
Bitmap.createBitmap(sourceBounds.width() + CROPPED_MARGIN * 2,
sourceBounds.height() + CROPPED_MARGIN * 2, mBitmap.getConfig());
canvas.setBitmap(croppedBitmap);
canvas.drawBitmap(fullScreenBitmap, sourceBounds, destBounds, null);
imageView.setImageBitmap(croppedBitmap);
// Add as member variable.
private static final int CROPPED_MARGIN = 100;