ImageFormat.java revision 9184ec307be30719b2b7bfc3fb3e0a1365ccdf73 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.graphics;
18
19public class ImageFormat {
20    /*
21     * these constants are chosen to be binary compatible with their previous
22     * location in PixelFormat.java
23     */
24
25    public static final int UNKNOWN = 0;
26
27    /**
28     * RGB format used for pictures encoded as RGB_565. See
29     * {@link android.hardware.Camera.Parameters#setPictureFormat(int)}.
30     */
31    public static final int RGB_565 = 4;
32
33    /**
34     * <p>Android YUV format.</p>
35     *
36     * <p>This format is exposed to software decoders and applications.</p>
37     *
38     * <p>YV12 is a 4:2:0 YCrCb planar format comprised of a WxH Y plane followed
39     * by (W/2) x (H/2) Cr and Cb planes.</p>
40     *
41     * <p>This format assumes
42     * <ul>
43     * <li>an even width</li>
44     * <li>an even height</li>
45     * <li>a horizontal stride multiple of 16 pixels</li>
46     * <li>a vertical stride equal to the height</li>
47     * </ul>
48     * </p>
49     *
50     * <pre> y_size = stride * height
51     * c_size = ALIGN(stride/2, 16) * height/2
52     * size = y_size + c_size * 2
53     * cr_offset = y_size
54     * cb_offset = y_size + c_size</pre>
55     *
56     * This format is guaranteed to be supported for camera preview images since
57     * API level 12; for earlier API versions, check
58     * {@link android.hardware.Camera.Parameters#getSupportedPreviewFormats()}.
59     * </p>
60     */
61    public static final int YV12 = 0x32315659;
62
63    /**
64     * YCbCr format, used for video. Whether this format is supported by the
65     * camera hardware can be determined by
66     * {@link android.hardware.Camera.Parameters#getSupportedPreviewFormats()}.
67     */
68    public static final int NV16 = 0x10;
69
70    /**
71     * YCrCb format used for images, which uses the NV21 encoding format. This
72     * is the default format for camera preview images, when not otherwise set
73     * with {@link android.hardware.Camera.Parameters#setPreviewFormat(int)}.
74     */
75    public static final int NV21 = 0x11;
76
77    /**
78     * YCbCr format used for images, which uses YUYV (YUY2) encoding format.
79     * This is an alternative format for camera preview images. Whether this
80     * format is supported by the camera hardware can be determined by
81     * {@link android.hardware.Camera.Parameters#getSupportedPreviewFormats()}.
82     */
83    public static final int YUY2 = 0x14;
84
85    /**
86     * Encoded formats. These are not necessarily supported by the hardware.
87     */
88    public static final int JPEG = 0x100;
89
90    /**
91     * Raw bayer format used for images, which is 10 bit precision samples
92     * stored in 16 bit words. The filter pattern is RGGB. Whether this format
93     * is supported by the camera hardware can be determined by
94     * {@link android.hardware.Camera.Parameters#getSupportedPreviewFormats()}.
95     *
96     * @hide
97     */
98    public static final int BAYER_RGGB = 0x200;
99
100    /**
101     * Use this function to retrieve the number of bits per pixel of an
102     * ImageFormat.
103     *
104     * @param format
105     * @return the number of bits per pixel of the given format or -1 if the
106     *         format doesn't exist or is not supported.
107     */
108    public static int getBitsPerPixel(int format) {
109        switch (format) {
110            case RGB_565:
111                return 16;
112            case NV16:
113                return 16;
114            case YUY2:
115                return 16;
116            case YV12:
117                return 12;
118            case NV21:
119                return 12;
120            case BAYER_RGGB:
121                return 16;
122        }
123        return -1;
124    }
125}
126