LegacyMetadataMapper.java revision 3e4fed203fe7c945c53c6d6bb9f160932a1d15b3 
1/*
2 * Copyright (C) 2014 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.hardware.camera2.legacy;
18
19import android.graphics.ImageFormat;
20import android.hardware.Camera;
21import android.hardware.Camera.CameraInfo;
22import android.hardware.Camera.Size;
23import android.hardware.camera2.CameraCharacteristics;
24import android.hardware.camera2.impl.CameraMetadataNative;
25import android.hardware.camera2.params.StreamConfiguration;
26import android.hardware.camera2.params.StreamConfigurationDuration;
27import android.util.Log;
28
29import java.util.ArrayList;
30import java.util.List;
31
32import static com.android.internal.util.Preconditions.*;
33import static android.hardware.camera2.CameraCharacteristics.*;
34
35/**
36 * Provide legacy-specific implementations of camera2 metadata for legacy devices, such as the
37 * camera characteristics.
38 */
39public class LegacyMetadataMapper {
40    private static final String TAG = "LegacyMetadataMapper";
41    private static final boolean VERBOSE = Log.isLoggable(TAG, Log.VERBOSE);
42
43    // from graphics.h
44    private static final int HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED = 0x22;
45    private static final int HAL_PIXEL_FORMAT_BLOB = 0x21;
46
47    private static final long APPROXIMATE_CAPTURE_DELAY_MS = 200; // ms
48    private static final long APPROXIMATE_SENSOR_AREA = (1 << 20); // 8mp
49    private static final long APPROXIMATE_JPEG_ENCODE_TIME = 600; // ms
50    private static final long NS_PER_MS = 1000000;
51
52    /**
53     * Create characteristics for a legacy device by mapping the {@code parameters}
54     * and {@code info}
55     *
56     * @param parameters A string parseable by {@link Camera.Parameters#unflatten}
57     * @param info Camera info with camera facing direction and angle of orientation
58     * @return static camera characteristics for a camera device
59     *
60     * @throws NullPointerException if any of the args were {@code null}
61     */
62    public static CameraCharacteristics createCharacteristics(String parameters,
63            android.hardware.CameraInfo info) {
64        checkNotNull(parameters, "parameters must not be null");
65        checkNotNull(info, "info must not be null");
66        checkNotNull(info.info, "info.info must not be null");
67
68        CameraMetadataNative m = new CameraMetadataNative();
69
70        mapCameraInfo(m, info.info);
71
72        Camera.Parameters params = Camera.getEmptyParameters();
73        params.unflatten(parameters);
74        mapCameraParameters(m, params);
75
76        if (VERBOSE) {
77            Log.v(TAG, "createCharacteristics metadata:");
78            Log.v(TAG, "--------------------------------------------------- (start)");
79            m.dumpToLog();
80            Log.v(TAG, "--------------------------------------------------- (end)");
81        }
82
83        return new CameraCharacteristics(m);
84    }
85
86    private static void mapCameraInfo(CameraMetadataNative m, CameraInfo i) {
87        m.set(LENS_FACING, i.facing == CameraInfo.CAMERA_FACING_BACK ?
88                LENS_FACING_BACK : LENS_FACING_FRONT);
89        m.set(SENSOR_ORIENTATION, i.orientation);
90    }
91
92    private static void mapCameraParameters(CameraMetadataNative m, Camera.Parameters p) {
93        mapStreamConfigs(m, p);
94
95        // TODO: map other fields
96    }
97
98    private static void mapStreamConfigs(CameraMetadataNative m, Camera.Parameters p) {
99
100        ArrayList<StreamConfiguration> availableStreamConfigs = new ArrayList<>();
101        /*
102         * Implementation-defined (preview, recording, etc) -> use camera1 preview sizes
103         * YUV_420_888 cpu callbacks -> use camera1 preview sizes
104         * Other preview callbacks (CPU) -> use camera1 preview sizes
105         * JPEG still capture -> use camera1 still capture sizes
106         *
107         * Use platform-internal format constants here, since StreamConfigurationMap does the
108         * remapping to public format constants.
109         */
110        List<Size> previewSizes = p.getSupportedPreviewSizes();
111        appendStreamConfig(availableStreamConfigs,
112                HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED, previewSizes);
113        appendStreamConfig(availableStreamConfigs,
114                ImageFormat.YUV_420_888, previewSizes);
115        for (int format : p.getSupportedPreviewFormats()) {
116            if (ImageFormat.isPublicFormat(format)) {
117                appendStreamConfig(availableStreamConfigs, format, previewSizes);
118            } else {
119                /*
120                 *  Do not add any formats unknown to us
121                 * (since it would fail runtime checks in StreamConfigurationMap)
122                 */
123                Log.w(TAG,
124                        String.format("mapStreamConfigs - Skipping non-public format %x", format));
125            }
126        }
127
128        List<Camera.Size> jpegSizes = p.getSupportedPictureSizes();
129        appendStreamConfig(availableStreamConfigs,
130                HAL_PIXEL_FORMAT_BLOB, p.getSupportedPictureSizes());
131        m.set(SCALER_AVAILABLE_STREAM_CONFIGURATIONS,
132                availableStreamConfigs.toArray(new StreamConfiguration[0]));
133
134        // No frame durations available
135        m.set(SCALER_AVAILABLE_MIN_FRAME_DURATIONS, new StreamConfigurationDuration[0]);
136
137        StreamConfigurationDuration[] jpegStalls =
138                new StreamConfigurationDuration[jpegSizes.size()];
139        int i = 0;
140        for (Camera.Size s : jpegSizes) {
141            jpegStalls[i++] = new StreamConfigurationDuration(HAL_PIXEL_FORMAT_BLOB, s.width,
142                    s.height, calculateJpegStallDuration(s));
143        }
144        // Set stall durations for jpeg, other formats use default stall duration
145        m.set(SCALER_AVAILABLE_STALL_DURATIONS, jpegStalls);
146    }
147
148    private static void appendStreamConfig(
149            ArrayList<StreamConfiguration> configs, int format, List<Camera.Size> sizes) {
150        for (Camera.Size size : sizes) {
151            StreamConfiguration config =
152                    new StreamConfiguration(format, size.width, size.height, /*input*/false);
153            configs.add(config);
154        }
155    }
156
157    /**
158     * Return the stall duration for a given output jpeg size in nanoseconds.
159     *
160     * <p>An 8mp image is chosen to have a stall duration of 0.8 seconds.</p>
161     */
162    private static long calculateJpegStallDuration(Camera.Size size) {
163        long baseDuration = APPROXIMATE_CAPTURE_DELAY_MS * NS_PER_MS; // 200ms for capture
164        long area = size.width * (long) size.height;
165        long stallPerArea = APPROXIMATE_JPEG_ENCODE_TIME * NS_PER_MS /
166                APPROXIMATE_SENSOR_AREA; // 600ms stall for 8mp
167        return baseDuration + area * stallPerArea;
168    }
169}
170