1 /*
2  * Copyright (C) 2019 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 
17 #ifndef ANDROID_SERVERS_CAMERA_EXIF_UTILS_H
18 #define ANDROID_SERVERS_CAMERA_EXIF_UTILS_H
19 
20 #include "CameraMetadata.h"
21 
22 namespace android {
23 namespace camera3 {
24 
25 /*
26  * Orientation value:
27  *  1      2      3      4      5          6          7          8
28  *
29  *  888888 888888     88 88     8888888888 88                 88 8888888888
30  *  88         88     88 88     88  88     88  88         88  88     88  88
31  *  8888     8888   8888 8888   88         8888888888 8888888888         88
32  *  88         88     88 88
33  *  88         88 888888 888888
34  */
35 enum ExifOrientation : uint16_t {
36     ORIENTATION_UNDEFINED   = 0x0,
37     ORIENTATION_0_DEGREES   = 0x1,
38     ORIENTATION_90_DEGREES  = 0x6,
39     ORIENTATION_180_DEGREES = 0x3,
40     ORIENTATION_270_DEGREES = 0x8,
41 };
42 
43 // This is based on the camera HIDL shim implementation, which was in turned
44 // based on original ChromeOS ARC implementation of a V4L2 HAL
45 
46 // ExifUtils can override APP1 segment with tags which caller set. ExifUtils can
47 // also add a thumbnail in the APP1 segment if thumbnail size is specified.
48 // ExifUtils can be reused with different images by calling initialize().
49 //
50 // Example of using this class :
51 //  std::unique_ptr<ExifUtils> utils(ExifUtils::Create());
52 //  utils->initialize(const unsigned char* app1Segment, size_t app1SegmentSize);
53 //  ...
54 //  // Call ExifUtils functions to set Exif tags.
55 //  ...
56 //  utils->GenerateApp1();
57 //  unsigned int app1Length = utils->GetApp1Length();
58 //  uint8_t* app1Buffer = new uint8_t[app1Length];
59 //  memcpy(app1Buffer, utils->GetApp1Buffer(), app1Length);
60 class ExifUtils {
61 
62 public:
63     virtual ~ExifUtils();
64 
65     static ExifUtils* create();
66 
67     // Initialize() can be called multiple times. The setting of Exif tags will be
68     // cleared.
69     virtual bool initialize(const unsigned char *app1Segment, size_t app1SegmentSize) = 0;
70     virtual bool initializeEmpty() = 0;
71 
72     // Set all known fields from a metadata structure
73     virtual bool setFromMetadata(const CameraMetadata& metadata,
74             const CameraMetadata& staticInfo,
75             const size_t imageWidth, const size_t imageHeight) = 0;
76 
77     // Sets the len aperture.
78     // Returns false if memory allocation fails.
79     virtual bool setAperture(float aperture) = 0;
80 
81     // sets the color space.
82     // Returns false if memory allocation fails.
83     virtual bool setColorSpace(uint16_t color_space) = 0;
84 
85     // Sets the date and time of image last modified. It takes local time. The
86     // name of the tag is DateTime in IFD0.
87     // Returns false if memory allocation fails.
88     virtual bool setDateTime(const struct tm& t) = 0;
89 
90     // Sets the digital zoom ratio. If the numerator is 0, it means digital zoom
91     // was not used.
92     // Returns false if memory allocation fails.
93     virtual bool setDigitalZoomRatio(uint32_t crop_width, uint32_t crop_height,
94             uint32_t sensor_width, uint32_t sensor_height) = 0;
95 
96     // Sets the exposure bias.
97     // Returns false if memory allocation fails.
98     virtual bool setExposureBias(int32_t ev,
99             uint32_t ev_step_numerator, uint32_t ev_step_denominator) = 0;
100 
101     // Sets the exposure mode set when the image was shot.
102     // Returns false if memory allocation fails.
103     virtual bool setExposureMode(uint8_t exposure_mode) = 0;
104 
105     // Sets the exposure time, given in seconds.
106     // Returns false if memory allocation fails.
107     virtual bool setExposureTime(float exposure_time) = 0;
108 
109     // Sets the status of flash.
110     // Returns false if memory allocation fails.
111     virtual bool setFlash(uint8_t flash_available, uint8_t flash_state, uint8_t ae_mode) = 0;
112 
113     // Sets the F number.
114     // Returns false if memory allocation fails.
115     virtual bool setFNumber(float f_number) = 0;
116 
117     // Sets the focal length of lens used to take the image in millimeters.
118     // Returns false if memory allocation fails.
119     virtual bool setFocalLength(float focal_length) = 0;
120 
121     // Sets the focal length of lens for 35mm film used to take the image in millimeters.
122     // Returns false if memory allocation fails.
123     virtual bool setFocalLengthIn35mmFilm(float focal_length,
124             float sensor_size_x, float sensor_size_y) = 0;
125 
126     // Sets the altitude in meters.
127     // Returns false if memory allocation fails.
128     virtual bool setGpsAltitude(double altitude) = 0;
129 
130     // Sets the latitude with degrees minutes seconds format.
131     // Returns false if memory allocation fails.
132     virtual bool setGpsLatitude(double latitude) = 0;
133 
134     // Sets the longitude with degrees minutes seconds format.
135     // Returns false if memory allocation fails.
136     virtual bool setGpsLongitude(double longitude) = 0;
137 
138     // Sets GPS processing method.
139     // Returns false if memory allocation fails.
140     virtual bool setGpsProcessingMethod(const std::string& method) = 0;
141 
142     // Sets GPS date stamp and time stamp (atomic clock). It takes UTC time.
143     // Returns false if memory allocation fails.
144     virtual bool setGpsTimestamp(const struct tm& t) = 0;
145 
146     // Sets the height (number of rows) of main image.
147     // Returns false if memory allocation fails.
148     virtual bool setImageHeight(uint32_t length) = 0;
149 
150     // Sets the width (number of columns) of main image.
151     // Returns false if memory allocation fails.
152     virtual bool setImageWidth(uint32_t width) = 0;
153 
154     // Sets the ISO speed.
155     // Returns false if memory allocation fails.
156     virtual bool setIsoSpeedRating(uint16_t iso_speed_ratings) = 0;
157 
158     // Sets the smallest F number of the lens.
159     // Returns false if memory allocation fails.
160     virtual bool setMaxAperture(float aperture) = 0;
161 
162     // Sets image orientation.
163     // Returns false if memory allocation fails.
164     virtual bool setOrientation(uint16_t degrees) = 0;
165 
166     // Sets image orientation.
167     // Returns false if memory allocation fails.
168     virtual bool setOrientationValue(ExifOrientation orientationValue) = 0;
169 
170     // Sets the shutter speed.
171     // Returns false if memory allocation fails.
172     virtual bool setShutterSpeed(float exposure_time) = 0;
173 
174     // Sets the distance to the subject, given in meters.
175     // Returns false if memory allocation fails.
176     virtual bool setSubjectDistance(float diopters) = 0;
177 
178     // Sets the fractions of seconds for the <DateTime> tag.
179     // Returns false if memory allocation fails.
180     virtual bool setSubsecTime(const std::string& subsec_time) = 0;
181 
182     // Sets the white balance mode set when the image was shot.
183     // Returns false if memory allocation fails.
184     virtual bool setWhiteBalance(uint8_t white_blanace) = 0;
185 
186     // Generates APP1 segment.
187     // Returns false if generating APP1 segment fails.
188     virtual bool generateApp1() = 0;
189 
190     // Gets buffer of APP1 segment. This method must be called only after calling
191     // GenerateAPP1().
192     virtual const uint8_t* getApp1Buffer() = 0;
193 
194     // Gets length of APP1 segment. This method must be called only after calling
195     // GenerateAPP1().
196     virtual unsigned int getApp1Length() = 0;
197 };
198 
199 } // namespace camera3
200 } // namespace android
201 
202 #endif  // ANDROID_SERVERS_CAMERA_EXIF_UTILS_H
203