Android 5: processing bitmap

Image processing includes the following:
1. Zoom
2. skew
3. Rotate
4. Zoom +
5. Translation
6. Images
The Code is as follows:
 
1. package com. mike. activity;
2.
3. import java. io. FileNotFoundException;
4.
5. import android. app. Activity;
6. import android. content. Intent;
7. import android. graphics. Bitmap;
8. import android. graphics. BitmapFactory;
9. import android. graphics. BitmapFactory. Options;
10. import android. graphics. Canvas;
11. import android. graphics. Color;
12. import android. graphics. Matrix;
13. import android. graphics. Paint;
14. import android.net. Uri;
15. import android. OS. Bundle;
16. import android. util. Log;
17. import android. view. Display;
18. import android. view. View;
19. import android. view. View. OnClickListener;
20. import android. widget. Button;
21. import android. widget. ImageView;
22.
23. public class ImageDemoActivity extends Activity implements OnClickListener {
24./** Called when the activity is first created .*/
25.
26. public static String TAG = "IMAGE ";
27. public static int REQUEST_CODE = 0;
28. private ImageView mImageShow;
29. private ImageView mImageAltered;
30.
31. @ Override
32. public void onCreate (Bundle savedInstanceState ){
33. super. onCreate (savedInstanceState );
34. setContentView (R. layout. main );
35.
36. Button imageSelectBtn = (Button) findViewById (R. id. imageSelectBtn );
37. mImageShow = (ImageView) findViewById (R. id. imageShow );
38. mImageAltered = (ImageView) findViewById (R. id. imageAltered );
39. imageSelectBtn. setOnClickListener (this );
40 .}
41.
42. public void onClick (View v ){
43. // TODO Auto-generated method stub
44. Intent intent = new Intent (Intent. ACTION_PICK,
45. android. provider. MediaStore. Images. Media. EXTERNAL_CONTENT_URI); // start the Photo Gallery
46. startActivityForResult (intent, 0 );
47 .}
48.
49. @ Override
50. protected void onActivityResult (int requestCode, int resultCode,
51. Intent intent ){
52. // TODO Auto-generated method stub
53. super. onActivityResult (requestCode, resultCode, intent );
54.
55. if (resultCode = RESULT_ OK) {// operation successful
56. Uri imgFileUri = intent. getData (); // obtain the information of the selected photo
57. Log. d (TAG, "imgFileUri is:" + imgFileUri );
58. // The returned image may be too large to be fully loaded into the memory. The system has restrictions and needs to be processed.
59. Display currentDisplay = getWindowManager (). getdefadisplay Display ();
60. int defaultHeight = currentDisplay. getHeight ();
61. int defaultWidth = currentDisplay. getWidth ();
62.
63. BitmapFactory. Options bitmapFactoryOptions = new BitmapFactory. Options ();
64. bitmapFactoryOptions. inJustDecodeBounds = false; // only obtains the size of the original image without returning the Bitmap object.
65. // Note: If set to true, the decoder will return null (no bitmap),
66. // the out... fields will still be set,
67. // allowing the caller to query the bitmap without having
68. // allocate the memory for its pixels
69. try {
70. Bitmap bitmap = BitmapFactory. decodeStream (getContentResolver ()
71 .. openInputStream (imgFileUri), null,
72. bitmapFactoryOptions );
73. int outHeight = bitmapFactoryOptions. outHeight;
74. int outWidth = bitmapFactoryOptions. outWidth;
75. int heightRatio = (int) Math. ceil (float) outHeight
76./defaultHeight );
77. int widthRatio = (int) Math. ceil (float) outWidth
78./defaultWidth );
79.
80. if (heightRatio> 1 | widthRatio> 1 ){
81. if (heightRatio> widthRatio ){
82. bitmapFactoryOptions. inSampleSize = heightRatio;
83.} else {
84. bitmapFactoryOptions. inSampleSize = widthRatio;
85 .}
86 .}
87.
88. bitmapFactoryOptions. inJustDecodeBounds = false;
89. bitmap = BitmapFactory. decodeStream (getContentResolver ()
90 .. openInputStream (imgFileUri), null,
91. bitmapFactoryOptions );
92.
93. mImageShow. setImageBitmap (bitmap );
94.
95 .///*
96. // * draw a bitmap on the in-place Graph
97 .//*/
98 .//
99. // Bitmap bitmapAltered = Bitmap. createBitmap (bitmap. getWidth (),
100. // bitmap. getHeight (), bitmap. getConfig ());
101 .//
102. // Canvas canvas = new
103. // Canvas (bitmapAltered); // bitmap provides the Canvas, only the size and size are provided here, and no background is displayed after the offset.
104 .//
105 .//
106. // Paint paint = new Paint ();
107 .//
108. // canvas. drawBitmap (bitmap, 0, 0, paint); // The image is exactly the same as the previous one.
109 .//
110. // mImageAltered. setImageBitmap (bitmapAltered );
111.
112 ./*
113. * use Matrix
114 .*/
115.
116. Bitmap bitmapAltered = Bitmap. createBitmap (bitmap. getWidth (),
117. bitmap. getHeight (), bitmap. getConfig (); // The disadvantage is to limit the size of the canvas. The processed image may be truncated. You can introduce a matrix Construction Method to dynamically set the size of the canvas www.2cto.com.
118. Canvas canvas = new Canvas (bitmapAltered); // bitmap provides the Canvas, only the size and size are provided here, and no background is displayed after the offset,
119. Paint paint = new Paint ();
120.
121. Matrix matrix = new Matrix ();
122.
123. // 1: Zoom
124. // matrix. setValues (new float [] {// basic knowledge of linear algebra that can be multiplied
125. //, 0, // calculate the value of x
126. // 0, 0, // calculate the value of y
127. //, 0, 1 // the two-dimensional graph is not used
128 .//});
129.
130. // 2: Tilt
131. // matrix. setValues (new float [] {// basic knowledge of linear algebra that can be multiplied
132. // 1,. 5f, 0, // calculate the value of x, which is related to the value of x and y.
133. // 0, 0, // calculate the value of y
134. //, 0, 1 // the two-dimensional graph is not used
135 .//});
136.
137. // 3: Rotate
138. // matrix. setRotate (45); // sets the rotation angle, (0, 0), and rotates 45 degrees clockwise.
139.
140. // 4, zoom plus: Use the Matrix class method // you need to modify the canvas width> 1.5 x the original width.
141. // matrix. setScale (1.5f, 1 );
142.
143. // 5, pan
144. // matrix. setTranslate (10, 0 );
145.
146. // 6, Image
147. // eg1: X axis Image
148. // matrix. setScale (-1, 1); // draw to the left. The original image is symmetric along the Y axis.
149. // matrix. postTranslate (bitmap. getWidth (), 0); // note that post is followed by moving
150. // eg2: Y axis Image
151. matrix. setScale (1,-1); // draw up. The original image is symmetric along the X axis and the image is in the fourth quadrant.
152. matrix. postTranslate (0, bitmap. getHeight (); // note that post is post moving
153.
154.
155 .//~ Optimize ~ Because bitmapAltered is specified for the canvas, the processed image may be truncated. The bitmapAltered size can be dynamically changed through the matrix.
156. // eg: matrix. setRotate (degrees, px, py)
157. // bitmapAltered = Bitmap. createBitmap (source, x, y, width, height, m, filter); // apparently the matrix affects its size
158.
159 .//
160.
161. // Note: for more details: Wikipedia Transformation Matrix
162. // http://en.wikipedia.org/wiki/Transformation_matrix
163.
164. canvas. drawBitmap (bitmap, matrix, paint); // The image is exactly the same as the previous one.
165.
166. mImageAltered. setImageBitmap (bitmapAltered );
167.
168.} catch (FileNotFoundException e ){
169. // TODO Auto-generated catch block
170. e. printStackTrace ();
171 .}
172.
173 .}
174 .}
175 .}

 
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