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comparison servlet/src/digilib/image/DocuImage.java @ 79:63c8186455c1

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Servlet version 1.6b. Further cleanup and new functionality: * mirroring * contrast/brightness * rotation (not finished)
author robcast
date Mon, 03 Feb 2003 16:04:53 +0100
parents 3b8797fc3e90
children 4e6757e8ccd4
comparison
equal deleted inserted replaced
78:e0dcac9c66fa 79:63c8186455c1
19 */ 19 */
20 20
21 package digilib.image; 21 package digilib.image;
22 22
23 import java.io.File; 23 import java.io.File;
24 24 import java.io.OutputStream;
25 import javax.servlet.ServletResponse;
26 25
27 import digilib.io.FileOpException; 26 import digilib.io.FileOpException;
28
29 27
30 /** The basic class for the representation of a digilib image. 28 /** The basic class for the representation of a digilib image.
31 * 29 *
32 * The actual image object is hidden in the class, only methods for loading, 30 * The actual image object is hidden in the class, only methods for loading,
33 * manipulation, and saving are exported. This strategy enables implementations 31 * manipulation, and saving are exported. This strategy enables implementations
34 * using different toolkits that rely on different image base classes (like 32 * using different toolkits that rely on different image base classes (like
35 * JIMI, Java2D and JAI). 33 * JIMI, Java2D and JAI).
36 */ 34 */
37 public interface DocuImage { 35 public interface DocuImage {
38 36
39 /** Returns the list of image file types known to the DocuImage implementation. 37 /** Returns the list of image file types known to the DocuImage implementation.
40 * 38 *
41 * @return List of image file types. Strings are standard file extensions. 39 * @return List of image file types. Strings are standard file extensions.
42 */ 40 */
43 public String[] getKnownFileTypes(); 41 public String[] getKnownFileTypes();
44 42
45 /** Loads an image file into the Object. 43 /** Loads an image file into the Object.
46 * 44 *
47 * @param f Image File. 45 * @param f Image File.
48 * @throws FileOpException Exception thrown if any error occurs. 46 * @throws FileOpException Exception thrown if any error occurs.
49 */ 47 */
50 public void loadImage(File f) throws FileOpException; 48 public void loadImage(File f) throws FileOpException;
51 49
52 /** Writes the current image to a ServletResponse. 50 /** Writes the current image to a ServletResponse.
53 * 51 *
54 * The image is encoded to the mime-type <code>mt</code> and sent to the output 52 * The image is encoded to the mime-type <code>mt</code> and sent to the output
55 * stream of the <code>ServletResponse</code> <code>res</code>. 53 * stream of the <code>ServletResponse</code> <code>res</code>.
56 * 54 *
57 * Currently only mime-types "image/jpeg" and "image/png" are supported. 55 * Currently only mime-types "image/jpeg" and "image/png" are supported.
58 * 56 *
59 * @param mt mime-type of the image to be sent. 57 * @param mt mime-type of the image to be sent.
60 * @param res ServletResponse where the image is sent. 58 * @param res ServletResponse where the image is sent.
61 * @throws FileOpException Exception thrown on any error. 59 * @throws FileOpException Exception thrown on any error.
62 */ 60 */
63 public void writeImage(String mt, ServletResponse res) throws FileOpException; 61 public void writeImage(String mt, OutputStream ostream)
62 throws FileOpException;
64 63
65 /** The width of the current image in pixel. 64 /** The width of the current image in pixel.
66 * 65 *
67 * @return Image width in pixels. 66 * @return Image width in pixels.
68 */ 67 */
69 public int getWidth(); 68 public int getWidth();
70
71 /** The height of the current image in pixel.
72 *
73 * @return Image height in pixels.
74 */
75 public int getHeight();
76 69
77 /** Crops and scales the current image. 70 /** The height of the current image in pixel.
78 * 71 *
79 * The current image is cropped to a rectangle of <code>width</code>, 72 * @return Image height in pixels.
80 * <code>height</code> at position <code>x_off</code>, <code>y_off</code>. The 73 */
81 * resulting image is scaled by the factor <code>scale</code> using the 74 public int getHeight();
82 * interpolation quality <code>qual</code> (0=worst). 75
83 * 76 /** Crops the current image.
84 * @param x_off x offset of the crop rectangle in pixel. 77 *
85 * @param y_off y offset of the crop rectangle in pixel. 78 * Cuts out a region of the size <code>width</code> x <code>height</code> at
86 * @param width width of the crop rectangle in pixel. 79 * the offset <code>xoff</code>, <code>yoff</code> from the current image
87 * @param height height of the crop rectangle in pixel. 80 * and replaces the current image with the result.
88 * @param scale scaling factor. 81 *
89 * @param qual interpolation quality (0=worst). 82 * @param xoff X offset of crop region
90 * @throws ImageOpException exception thrown on any error. 83 * @param yoff Y offset of crop region
91 */ 84 * @param width width of crop region
92 public void cropAndScale( 85 * @param height height of crop region
93 int x_off, int y_off, 86 * @throws ImageOpException
94 int width, int height, 87 */
95 float scale, int qual) throws ImageOpException; 88 public void crop(int xoff, int yoff, int width, int height)
89 throws ImageOpException;
90
91 /** Scales the current image.
92 *
93 * Replaces the current image with an image scaled by the factor
94 * <code>scale</code>.
95 *
96 * @param scale scaling factor
97 * @throws ImageOpException
98 */
99 public void scale(double scale) throws ImageOpException;
100
101 /** Crops and scales the current image.
102 *
103 * The current image is cropped to a rectangle of <code>width</code>,
104 * <code>height</code> at position <code>x_off</code>, <code>y_off</code>. The
105 * resulting image is scaled by the factor <code>scale</code> using the
106 * interpolation quality <code>qual</code> (0=worst).
107 *
108 * @param x_off x offset of the crop rectangle in pixel.
109 * @param y_off y offset of the crop rectangle in pixel.
110 * @param width width of the crop rectangle in pixel.
111 * @param height height of the crop rectangle in pixel.
112 * @param scale scaling factor.
113 * @param qual interpolation quality (0=worst).
114 * @throws ImageOpException exception thrown on any error.
115 */
116 public void cropAndScale(
117 int x_off,
118 int y_off,
119 int width,
120 int height,
121 double scale,
122 int qual)
123 throws ImageOpException;
124
125 /** Rotates the current image.
126 *
127 * Replaces the current image with a rotated image. The image is rotated
128 * around the center by <code>angle</code> given in degrees [0, 360]
129 * clockwise. Image size and aspect ratio are likely to change.
130 *
131 * @param angle rotation angle in degree
132 */
133 public void rotate(double angle) throws ImageOpException;
134
135 /** Mirrors the current image.
136 *
137 * Replaces the current image with a mirrored image. The mirror axis goes
138 * through the center of the image and is rotated by <code>angle</code>
139 * degrees. Currently only horizontal and vertical mirroring (0 and 90
140 * degree) are supported.
141 *
142 * @param angle angle of mirror axis
143 * @throws ImageOpException
144 */
145 public void mirror(double angle) throws ImageOpException;
146
147 /** Enhaces brightness and contrast of the current image.
148 *
149 * Replaces the current image with a brightness and contrast enhanced image.
150 * Contrast is enhanced by multiplying the pixel value with the constant
151 * <code>mult</code>. Brightness is enhanced by adding the constant
152 * <code>add</code> to the pixel value. Operation: p1 = (p0*mult)+add.
153 *
154 * @param mult multiplicative constant for contrast enhancement
155 * @param add additive constant for brightness enhancement
156 * @throws ImageOpException
157 */
158 public void enhance(double mult, double add) throws ImageOpException;
159
160 /**
161 * Returns the interpolation quality.
162 * @return int
163 */
164 public int getQuality();
165
166 /**
167 * Sets the interpolation quality.
168 * @param quality The quality to set
169 */
170 public void setQuality(int quality);
171
96 } 172 }