1 /* 2 * Copyright (C) 2015 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 /** 18 * @addtogroup Camera 19 * @{ 20 */ 21 22 /** 23 * @file NdkCameraManager.h 24 */ 25 26 /* 27 * This file defines an NDK API. 28 * Do not remove methods. 29 * Do not change method signatures. 30 * Do not change the value of constants. 31 * Do not change the size of any of the classes defined in here. 32 * Do not reference types that are not part of the NDK. 33 * Do not #include files that aren't part of the NDK. 34 */ 35 36 #ifndef _NDK_CAMERA_MANAGER_H 37 #define _NDK_CAMERA_MANAGER_H 38 39 #include <sys/cdefs.h> 40 41 #include "NdkCameraError.h" 42 #include "NdkCameraMetadata.h" 43 #include "NdkCameraDevice.h" 44 45 __BEGIN_DECLS 46 47 #if __ANDROID_API__ >= 24 48 49 /** 50 * ACameraManager is opaque type that provides access to camera service. 51 * 52 * A pointer can be obtained using {@link ACameraManager_create} method. 53 */ 54 typedef struct ACameraManager ACameraManager; 55 56 /** 57 * Create ACameraManager instance. 58 * 59 * <p>The ACameraManager is responsible for 60 * detecting, characterizing, and connecting to {@link ACameraDevice}s.</p> 61 * 62 * <p>The caller must call {@link ACameraManager_delete} to free the resources once it is done 63 * using the ACameraManager instance.</p> 64 * 65 * @return a {@link ACameraManager} instance. 66 * 67 */ 68 ACameraManager* ACameraManager_create() __INTRODUCED_IN(24); 69 70 /** 71 * <p>Delete the {@link ACameraManager} instance and free its resources. </p> 72 * 73 * @param manager the {@link ACameraManager} instance to be deleted. 74 */ 75 void ACameraManager_delete(ACameraManager* manager) __INTRODUCED_IN(24); 76 77 /** 78 * Create a list of currently connected camera devices, including 79 * cameras that may be in use by other camera API clients. 80 * 81 * <p>Non-removable cameras use integers starting at 0 for their 82 * identifiers, while removable cameras have a unique identifier for each 83 * individual device, even if they are the same model.</p> 84 * 85 * <p>ACameraManager_getCameraIdList will allocate and return an {@link ACameraIdList}. 86 * The caller must call {@link ACameraManager_deleteCameraIdList} to free the memory</p> 87 * 88 * <p>Note: the returned camera list might be a subset to the output of <a href= 89 * "https://developer.android.com/reference/android/hardware/camera2/CameraManager.html#getCameraIdList()"> 90 * SDK CameraManager#getCameraIdList API</a> as the NDK API does not support some legacy camera 91 * hardware.</p> 92 * 93 * @param manager the {@link ACameraManager} of interest 94 * @param cameraIdList the output {@link ACameraIdList} will be filled in here if the method call 95 * succeeds. 96 * 97 * @return <ul> 98 * <li>{@link ACAMERA_OK} if the method call succeeds.</li> 99 * <li>{@link ACAMERA_ERROR_INVALID_PARAMETER} if manager or cameraIdList is NULL.</li> 100 * <li>{@link ACAMERA_ERROR_CAMERA_DISCONNECTED} if connection to camera service fails.</li> 101 * <li>{@link ACAMERA_ERROR_NOT_ENOUGH_MEMORY} if allocating memory fails.</li></ul> 102 */ 103 camera_status_t ACameraManager_getCameraIdList(ACameraManager* manager, 104 /*out*/ACameraIdList** cameraIdList) __INTRODUCED_IN(24); 105 106 /** 107 * Delete a list of camera devices allocated via {@link ACameraManager_getCameraIdList}. 108 * 109 * @param cameraIdList the {@link ACameraIdList} to be deleted. 110 */ 111 void ACameraManager_deleteCameraIdList(ACameraIdList* cameraIdList) __INTRODUCED_IN(24); 112 113 /** 114 * Definition of camera availability callbacks. 115 * 116 * @param context The optional application context provided by user in 117 * {@link ACameraManager_AvailabilityCallbacks}. 118 * @param cameraId The ID of the camera device whose availability is changing. The memory of this 119 * argument is owned by camera framework and will become invalid immediately after 120 * this callback returns. 121 */ 122 typedef void (*ACameraManager_AvailabilityCallback)(void* context, 123 const char* cameraId); 124 125 /** 126 * A listener for camera devices becoming available or unavailable to open. 127 * 128 * <p>Cameras become available when they are no longer in use, or when a new 129 * removable camera is connected. They become unavailable when some 130 * application or service starts using a camera, or when a removable camera 131 * is disconnected.</p> 132 * 133 * @see ACameraManager_registerAvailabilityCallback 134 */ 135 typedef struct ACameraManager_AvailabilityListener { 136 /// Optional application context. 137 void* context; 138 /// Called when a camera becomes available 139 ACameraManager_AvailabilityCallback onCameraAvailable; 140 /// Called when a camera becomes unavailable 141 ACameraManager_AvailabilityCallback onCameraUnavailable; 142 } ACameraManager_AvailabilityCallbacks; 143 144 /** 145 * Register camera availability callbacks. 146 * 147 * <p>onCameraUnavailable will be called whenever a camera device is opened by any camera API client. 148 * Other camera API clients may still be able to open such a camera device, evicting the existing 149 * client if they have higher priority than the existing client of a camera device. 150 * See {@link ACameraManager_openCamera} for more details.</p> 151 * 152 * <p>The callbacks will be called on a dedicated thread shared among all ACameraManager 153 * instances.</p> 154 * 155 * <p>Since this callback will be registered with the camera service, remember to unregister it 156 * once it is no longer needed; otherwise the callback will continue to receive events 157 * indefinitely and it may prevent other resources from being released. Specifically, the 158 * callbacks will be invoked independently of the general activity lifecycle and independently 159 * of the state of individual ACameraManager instances.</p> 160 * 161 * @param manager the {@link ACameraManager} of interest. 162 * @param callback the {@link ACameraManager_AvailabilityCallbacks} to be registered. 163 * 164 * @return <ul> 165 * <li>{@link ACAMERA_OK} if the method call succeeds.</li> 166 * <li>{@link ACAMERA_ERROR_INVALID_PARAMETER} if manager or callback is NULL, or 167 * {ACameraManager_AvailabilityCallbacks#onCameraAvailable} or 168 * {ACameraManager_AvailabilityCallbacks#onCameraUnavailable} is NULL.</li></ul> 169 */ 170 camera_status_t ACameraManager_registerAvailabilityCallback( 171 ACameraManager* manager, 172 const ACameraManager_AvailabilityCallbacks* callback) __INTRODUCED_IN(24); 173 174 /** 175 * Unregister camera availability callbacks. 176 * 177 * <p>Removing a callback that isn't registered has no effect.</p> 178 * 179 * @param manager the {@link ACameraManager} of interest. 180 * @param callback the {@link ACameraManager_AvailabilityCallbacks} to be unregistered. 181 * 182 * @return <ul> 183 * <li>{@link ACAMERA_OK} if the method call succeeds.</li> 184 * <li>{@link ACAMERA_ERROR_INVALID_PARAMETER} if callback, 185 * {ACameraManager_AvailabilityCallbacks#onCameraAvailable} or 186 * {ACameraManager_AvailabilityCallbacks#onCameraUnavailable} is NULL.</li></ul> 187 */ 188 camera_status_t ACameraManager_unregisterAvailabilityCallback( 189 ACameraManager* manager, 190 const ACameraManager_AvailabilityCallbacks* callback) __INTRODUCED_IN(24); 191 192 /** 193 * Query the capabilities of a camera device. These capabilities are 194 * immutable for a given camera. 195 * 196 * <p>See {@link ACameraMetadata} document and {@link NdkCameraMetadataTags.h} for more details.</p> 197 * 198 * <p>The caller must call {@link ACameraMetadata_free} to free the memory of the output 199 * characteristics.</p> 200 * 201 * @param manager the {@link ACameraManager} of interest. 202 * @param cameraId the ID string of the camera device of interest. 203 * @param characteristics the output {@link ACameraMetadata} will be filled here if the method call 204 * succeeeds. 205 * 206 * @return <ul> 207 * <li>{@link ACAMERA_OK} if the method call succeeds.</li> 208 * <li>{@link ACAMERA_ERROR_INVALID_PARAMETER} if manager, cameraId, or characteristics 209 * is NULL, or cameraId does not match any camera devices connected.</li> 210 * <li>{@link ACAMERA_ERROR_CAMERA_DISCONNECTED} if connection to camera service fails.</li> 211 * <li>{@link ACAMERA_ERROR_NOT_ENOUGH_MEMORY} if allocating memory fails.</li> 212 * <li>{@link ACAMERA_ERROR_UNKNOWN} if the method fails for some other reasons.</li></ul> 213 */ 214 camera_status_t ACameraManager_getCameraCharacteristics( 215 ACameraManager* manager, const char* cameraId, 216 /*out*/ACameraMetadata** characteristics) __INTRODUCED_IN(24); 217 218 /** 219 * Open a connection to a camera with the given ID. The opened camera device will be 220 * returned in the `device` parameter. 221 * 222 * <p>Use {@link ACameraManager_getCameraIdList} to get the list of available camera 223 * devices. Note that even if an id is listed, open may fail if the device 224 * is disconnected between the calls to {@link ACameraManager_getCameraIdList} and 225 * {@link ACameraManager_openCamera}, or if a higher-priority camera API client begins using the 226 * camera device.</p> 227 * 228 * <p>Devices for which the 229 * {@link ACameraManager_AvailabilityCallbacks#onCameraUnavailable} callback has been called due to 230 * the device being in use by a lower-priority, background camera API client can still potentially 231 * be opened by calling this method when the calling camera API client has a higher priority 232 * than the current camera API client using this device. In general, if the top, foreground 233 * activity is running within your application process, your process will be given the highest 234 * priority when accessing the camera, and this method will succeed even if the camera device is 235 * in use by another camera API client. Any lower-priority application that loses control of the 236 * camera in this way will receive an 237 * {@link ACameraDevice_StateCallbacks#onDisconnected} callback.</p> 238 * 239 * <p>Once the camera is successfully opened,the ACameraDevice can then be set up 240 * for operation by calling {@link ACameraDevice_createCaptureSession} and 241 * {@link ACameraDevice_createCaptureRequest}.</p> 242 * 243 * <p>If the camera becomes disconnected after this function call returns, 244 * {@link ACameraDevice_StateCallbacks#onDisconnected} with a 245 * ACameraDevice in the disconnected state will be called.</p> 246 * 247 * <p>If the camera runs into error after this function call returns, 248 * {@link ACameraDevice_StateCallbacks#onError} with a 249 * ACameraDevice in the error state will be called.</p> 250 * 251 * @param manager the {@link ACameraManager} of interest. 252 * @param cameraId the ID string of the camera device to be opened. 253 * @param callback the {@link ACameraDevice_StateCallbacks} associated with the opened camera device. 254 * @param device the opened {@link ACameraDevice} will be filled here if the method call succeeds. 255 * 256 * @return <ul> 257 * <li>{@link ACAMERA_OK} if the method call succeeds.</li> 258 * <li>{@link ACAMERA_ERROR_INVALID_PARAMETER} if manager, cameraId, callback, or device 259 * is NULL, or cameraId does not match any camera devices connected.</li> 260 * <li>{@link ACAMERA_ERROR_CAMERA_DISCONNECTED} if connection to camera service fails.</li> 261 * <li>{@link ACAMERA_ERROR_NOT_ENOUGH_MEMORY} if allocating memory fails.</li> 262 * <li>{@link ACAMERA_ERROR_CAMERA_IN_USE} if camera device is being used by a higher 263 * priority camera API client.</li> 264 * <li>{@link ACAMERA_ERROR_MAX_CAMERA_IN_USE} if the system-wide limit for number of open 265 * cameras or camera resources has been reached, and more camera devices cannot be 266 * opened until previous instances are closed.</li> 267 * <li>{@link ACAMERA_ERROR_CAMERA_DISABLED} if the camera is disabled due to a device 268 * policy, and cannot be opened.</li> 269 * <li>{@link ACAMERA_ERROR_PERMISSION_DENIED} if the application does not have permission 270 * to open camera.</li> 271 * <li>{@link ACAMERA_ERROR_UNKNOWN} if the method fails for some other reasons.</li></ul> 272 */ 273 camera_status_t ACameraManager_openCamera( 274 ACameraManager* manager, const char* cameraId, 275 ACameraDevice_StateCallbacks* callback, 276 /*out*/ACameraDevice** device) __INTRODUCED_IN(24); 277 278 #endif /* __ANDROID_API__ >= 24 */ 279 280 #if __ANDROID_API__ >= 29 281 282 /** 283 * Definition of camera access permission change callback. 284 * 285 * <p>Notification that camera access priorities have changed and the camera may 286 * now be openable. An application that was previously denied camera access due to 287 * a higher-priority user already using the camera, or that was disconnected from an 288 * active camera session due to a higher-priority user trying to open the camera, 289 * should try to open the camera again if it still wants to use it. Note that 290 * multiple applications may receive this callback at the same time, and only one of 291 * them will succeed in opening the camera in practice, depending on exact access 292 * priority levels and timing. This method is useful in cases where multiple 293 * applications may be in the resumed state at the same time, and the user switches 294 * focus between them, or if the current camera-using application moves between 295 * full-screen and Picture-in-Picture (PiP) states. In such cases, the camera 296 * available/unavailable callbacks will not be invoked, but another application may 297 * now have higher priority for camera access than the current camera-using 298 * application.</p> 299 300 * @param context The optional application context provided by user in 301 * {@link ACameraManager_AvailabilityListener}. 302 */ 303 typedef void (*ACameraManager_AccessPrioritiesChangedCallback)(void* context); 304 305 /** 306 * A listener for camera devices becoming available/unavailable to open or when 307 * the camera access permissions change. 308 * 309 * <p>Cameras become available when they are no longer in use, or when a new 310 * removable camera is connected. They become unavailable when some 311 * application or service starts using a camera, or when a removable camera 312 * is disconnected.</p> 313 * 314 * @see ACameraManager_registerExtendedAvailabilityCallback 315 */ 316 typedef struct ACameraManager_ExtendedAvailabilityListener { 317 /// 318 ACameraManager_AvailabilityCallbacks availabilityCallbacks; 319 320 /// Called when there is camera access permission change 321 ACameraManager_AccessPrioritiesChangedCallback onCameraAccessPrioritiesChanged; 322 323 /// Reserved for future use, please ensure that all entries are set to NULL 324 void *reserved[6]; 325 } ACameraManager_ExtendedAvailabilityCallbacks; 326 327 /** 328 * Register camera extended availability callbacks. 329 * 330 * <p>onCameraUnavailable will be called whenever a camera device is opened by any camera API 331 * client. Other camera API clients may still be able to open such a camera device, evicting the 332 * existing client if they have higher priority than the existing client of a camera device. 333 * See {@link ACameraManager_openCamera} for more details.</p> 334 * 335 * <p>The callbacks will be called on a dedicated thread shared among all ACameraManager 336 * instances.</p> 337 * 338 * <p>Since this callback will be registered with the camera service, remember to unregister it 339 * once it is no longer needed; otherwise the callback will continue to receive events 340 * indefinitely and it may prevent other resources from being released. Specifically, the 341 * callbacks will be invoked independently of the general activity lifecycle and independently 342 * of the state of individual ACameraManager instances.</p> 343 * 344 * @param manager the {@link ACameraManager} of interest. 345 * @param callback the {@link ACameraManager_ExtendedAvailabilityCallbacks} to be registered. 346 * 347 * @return <ul> 348 * <li>{@link ACAMERA_OK} if the method call succeeds.</li> 349 * <li>{@link ACAMERA_ERROR_INVALID_PARAMETER} if manager or callback is NULL, or 350 * {ACameraManager_ExtendedAvailabilityCallbacks#onCameraAccessPrioritiesChanged} 351 * or {ACameraManager_AvailabilityCallbacks#onCameraAvailable} or 352 * {ACameraManager_AvailabilityCallbacks#onCameraUnavailable} is NULL.</li></ul> 353 */ 354 camera_status_t ACameraManager_registerExtendedAvailabilityCallback( 355 ACameraManager* manager, 356 const ACameraManager_ExtendedAvailabilityCallbacks* callback) __INTRODUCED_IN(29); 357 358 /** 359 * Unregister camera extended availability callbacks. 360 * 361 * <p>Removing a callback that isn't registered has no effect.</p> 362 * 363 * @param manager the {@link ACameraManager} of interest. 364 * @param callback the {@link ACameraManager_ExtendedAvailabilityCallbacks} to be unregistered. 365 * 366 * @return <ul> 367 * <li>{@link ACAMERA_OK} if the method call succeeds.</li> 368 * <li>{@link ACAMERA_ERROR_INVALID_PARAMETER} if callback, 369 * {ACameraManager_ExtendedAvailabilityCallbacks#onCameraAccessPrioritiesChanged} 370 * or {ACameraManager_AvailabilityCallbacks#onCameraAvailable} or 371 * {ACameraManager_AvailabilityCallbacks#onCameraUnavailable} is NULL.</li></ul> 372 */ 373 camera_status_t ACameraManager_unregisterExtendedAvailabilityCallback( 374 ACameraManager* manager, 375 const ACameraManager_ExtendedAvailabilityCallbacks* callback) __INTRODUCED_IN(29); 376 377 #ifdef __ANDROID_VNDK__ 378 /** 379 * Retrieve the tag value, given the tag name and camera id. 380 * This method is device specific since some metadata might be defined by device manufacturers 381 * and might only be accessible for specific cameras. 382 * @param manager The {@link ACameraManager} of interest. 383 * @param cameraId The cameraId, which is used to query camera characteristics. 384 * @param name The name of the tag being queried. 385 * @param tag The output tag assigned by this method. 386 * 387 * @return ACAMERA_OK only if the function call was successful. 388 */ 389 camera_status_t ACameraManager_getTagFromName(ACameraManager *manager, const char* cameraId, 390 const char *name, /*out*/uint32_t *tag) 391 __INTRODUCED_IN(29); 392 #endif 393 394 #endif /* __ANDROID_API__ >= 29 */ 395 396 __END_DECLS 397 398 #endif /* _NDK_CAMERA_MANAGER_H */ 399 400 /** @} */ 401