1 /* 2 * Copyright (C) 2016 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 Media 19 * @{ 20 */ 21 22 /** 23 * @file NdkImageReader.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_IMAGE_READER_H 37 #define _NDK_IMAGE_READER_H 38 39 #include <sys/cdefs.h> 40 #ifdef __ANDROID_VNDK__ 41 #include <cutils/native_handle.h> 42 #endif 43 44 #include <android/native_window.h> 45 #include "NdkMediaError.h" 46 #include "NdkImage.h" 47 48 __BEGIN_DECLS 49 50 /** 51 * AImage is an opaque type that allows direct application access to image data rendered into a 52 * {@link ANativeWindow}. 53 */ 54 typedef struct AImageReader AImageReader; 55 56 #if __ANDROID_API__ >= 24 57 58 /** 59 * Create a new reader for images of the desired size and format. 60 * 61 * <p> 62 * The maxImages parameter determines the maximum number of {@link AImage} objects that can be 63 * acquired from the {@link AImageReader} simultaneously. Requesting more buffers will use up 64 * more memory, so it is important to use only the minimum number necessary for the use case. 65 * </p> 66 * <p> 67 * The valid sizes and formats depend on the source of the image data. 68 * </p> 69 * 70 * @param width The default width in pixels of the Images that this reader will produce. 71 * @param height The default height in pixels of the Images that this reader will produce. 72 * @param format The format of the Image that this reader will produce. This must be one of the 73 * AIMAGE_FORMAT_* enum value defined in {@link AIMAGE_FORMATS}. Note that not all 74 * formats are supported. One example is {@link AIMAGE_FORMAT_PRIVATE}, as it is not 75 * intended to be read by applications directly. That format is supported by 76 * {@link AImageReader_newWithUsage} introduced in API 26. 77 * @param maxImages The maximum number of images the user will want to access simultaneously. This 78 * should be as small as possible to limit memory use. Once maxImages Images are obtained 79 * by the user, one of them has to be released before a new {@link AImage} will become 80 * available for access through {@link AImageReader_acquireLatestImage} or 81 * {@link AImageReader_acquireNextImage}. Must be greater than 0. 82 * @param reader The created image reader will be filled here if the method call succeeeds. 83 * 84 * @return <ul> 85 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 86 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader is NULL, or one or more of width, 87 * height, format, maxImages arguments is not supported.</li> 88 * <li>{@link AMEDIA_ERROR_UNKNOWN} if the method fails for some other reasons.</li></ul> 89 * 90 * @see AImage 91 */ 92 media_status_t AImageReader_new( 93 int32_t width, int32_t height, int32_t format, int32_t maxImages, 94 /*out*/AImageReader** reader) __INTRODUCED_IN(24); 95 96 /** 97 * Delete an {@link AImageReader} and return all images generated by this reader to system. 98 * 99 * <p>This method will return all {@link AImage} objects acquired by this reader (via 100 * {@link AImageReader_acquireNextImage} or {@link AImageReader_acquireLatestImage}) to system, 101 * making any of data pointers obtained from {@link AImage_getPlaneData} invalid. Do NOT access 102 * the reader object or any of those data pointers after this method returns.</p> 103 * 104 * @param reader The image reader to be deleted. 105 */ 106 void AImageReader_delete(AImageReader* reader) __INTRODUCED_IN(24); 107 108 /** 109 * Get a {@link ANativeWindow} that can be used to produce {@link AImage} for this image reader. 110 * 111 * @param reader The image reader of interest. 112 * @param window The output {@link ANativeWindow} will be filled here if the method call succeeds. 113 * The {@link ANativeWindow} is managed by this image reader. Do NOT call 114 * {@link ANativeWindow_release} on it. Instead, use {@link AImageReader_delete}. 115 * 116 * @return <ul> 117 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 118 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader or window is NULL.</li></ul> 119 */ 120 media_status_t AImageReader_getWindow(AImageReader* reader, /*out*/ANativeWindow** window) __INTRODUCED_IN(24); 121 122 /** 123 * Query the default width of the {@link AImage} generated by this reader, in pixels. 124 * 125 * <p>The width may be overridden by the producer sending buffers to this reader's 126 * {@link ANativeWindow}. If so, the actual width of the images can be found using 127 * {@link AImage_getWidth}.</p> 128 * 129 * @param reader The image reader of interest. 130 * @param width the default width of the reader will be filled here if the method call succeeeds. 131 * 132 * @return <ul> 133 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 134 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader or width is NULL.</li></ul> 135 */ 136 media_status_t AImageReader_getWidth(const AImageReader* reader, /*out*/int32_t* width) __INTRODUCED_IN(24); 137 138 /** 139 * Query the default height of the {@link AImage} generated by this reader, in pixels. 140 * 141 * <p>The height may be overridden by the producer sending buffers to this reader's 142 * {@link ANativeWindow}. If so, the actual height of the images can be found using 143 * {@link AImage_getHeight}.</p> 144 * 145 * @param reader The image reader of interest. 146 * @param height the default height of the reader will be filled here if the method call succeeeds. 147 * 148 * @return <ul> 149 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 150 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader or height is NULL.</li></ul> 151 */ 152 media_status_t AImageReader_getHeight(const AImageReader* reader, /*out*/int32_t* height) __INTRODUCED_IN(24); 153 154 /** 155 * Query the format of the {@link AImage} generated by this reader. 156 * 157 * @param reader The image reader of interest. 158 * @param format the fromat of the reader will be filled here if the method call succeeeds. The 159 * value will be one of the AIMAGE_FORMAT_* enum value defiend in {@link NdkImage.h}. 160 * 161 * @return <ul> 162 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 163 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader or format is NULL.</li></ul> 164 */ 165 media_status_t AImageReader_getFormat(const AImageReader* reader, /*out*/int32_t* format) __INTRODUCED_IN(24); 166 167 /** 168 * Query the maximum number of concurrently acquired {@link AImage}s of this reader. 169 * 170 * @param reader The image reader of interest. 171 * @param maxImages the maximum number of concurrently acquired images of the reader will be filled 172 * here if the method call succeeeds. 173 * 174 * @return <ul> 175 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 176 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader or maxImages is NULL.</li></ul> 177 */ 178 media_status_t AImageReader_getMaxImages(const AImageReader* reader, /*out*/int32_t* maxImages) __INTRODUCED_IN(24); 179 180 /** 181 * Acquire the next {@link AImage} from the image reader's queue. 182 * 183 * <p>Warning: Consider using {@link AImageReader_acquireLatestImage} instead, as it will 184 * automatically release older images, and allow slower-running processing routines to catch 185 * up to the newest frame. Usage of {@link AImageReader_acquireNextImage} is recommended for 186 * batch/background processing. Incorrectly using this method can cause images to appear 187 * with an ever-increasing delay, followed by a complete stall where no new images seem to appear. 188 * </p> 189 * 190 * <p> 191 * This method will fail if {@link AImageReader_getMaxImages maxImages} have been acquired with 192 * {@link AImageReader_acquireNextImage} or {@link AImageReader_acquireLatestImage}. In particular 193 * a sequence of {@link AImageReader_acquireNextImage} or {@link AImageReader_acquireLatestImage} 194 * calls greater than {@link AImageReader_getMaxImages maxImages} without calling 195 * {@link AImage_delete} in-between will exhaust the underlying queue. At such a time, 196 * {@link AMEDIA_IMGREADER_MAX_IMAGES_ACQUIRED} will be returned until more images are released with 197 * {@link AImage_delete}. 198 * </p> 199 * 200 * @param reader The image reader of interest. 201 * @param image the acquired {@link AImage} will be filled here if the method call succeeeds. 202 * 203 * @return <ul> 204 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 205 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader or image is NULL.</li> 206 * <li>{@link AMEDIA_IMGREADER_MAX_IMAGES_ACQUIRED} if the number of concurrently acquired 207 * images has reached the limit.</li> 208 * <li>{@link AMEDIA_IMGREADER_NO_BUFFER_AVAILABLE} if there is no buffers currently 209 * available in the reader queue.</li> 210 * <li>{@link AMEDIA_ERROR_UNKNOWN} if the method fails for some other reasons.</li></ul> 211 * 212 * @see AImageReader_acquireLatestImage 213 */ 214 media_status_t AImageReader_acquireNextImage(AImageReader* reader, /*out*/AImage** image) __INTRODUCED_IN(24); 215 216 /** 217 218 * Acquire the latest {@link AImage} from the image reader's queue, dropping older images. 219 * 220 * <p> 221 * This operation will acquire all the images possible from the image reader, but 222 * {@link AImage_delete} all images that aren't the latest. This function is recommended to use over 223 * {@link AImageReader_acquireNextImage} for most use-cases, as it's more suited for real-time 224 * processing. 225 * </p> 226 * <p> 227 * Note that {@link AImageReader_getMaxImages maxImages} should be at least 2 for 228 * {@link AImageReader_acquireLatestImage} to be any different than 229 * {@link AImageReader_acquireNextImage} - discarding all-but-the-newest {@link AImage} requires 230 * temporarily acquiring two {@link AImage}s at once. Or more generally, calling 231 * {@link AImageReader_acquireLatestImage} with less than two images of margin, that is 232 * (maxImages - currentAcquiredImages < 2) will not discard as expected. 233 * </p> 234 * <p> 235 * This method will fail if {@link AImageReader_getMaxImages maxImages} have been acquired with 236 * {@link AImageReader_acquireNextImage} or {@link AImageReader_acquireLatestImage}. In particular 237 * a sequence of {@link AImageReader_acquireNextImage} or {@link AImageReader_acquireLatestImage} 238 * calls greater than {@link AImageReader_getMaxImages maxImages} without calling 239 * {@link AImage_delete} in-between will exhaust the underlying queue. At such a time, 240 * {@link AMEDIA_IMGREADER_MAX_IMAGES_ACQUIRED} will be returned until more images are released with 241 * {@link AImage_delete}. 242 * </p> 243 * 244 * @param reader The image reader of interest. 245 * @param image the acquired {@link AImage} will be filled here if the method call succeeeds. 246 * 247 * @return <ul> 248 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 249 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader or image is NULL.</li> 250 * <li>{@link AMEDIA_IMGREADER_MAX_IMAGES_ACQUIRED} if the number of concurrently acquired 251 * images has reached the limit.</li> 252 * <li>{@link AMEDIA_IMGREADER_NO_BUFFER_AVAILABLE} if there is no buffers currently 253 * available in the reader queue.</li> 254 * <li>{@link AMEDIA_ERROR_UNKNOWN} if the method fails for some other reasons.</li></ul> 255 * 256 * @see AImageReader_acquireNextImage 257 */ 258 media_status_t AImageReader_acquireLatestImage(AImageReader* reader, /*out*/AImage** image) __INTRODUCED_IN(24); 259 260 261 /** 262 * Signature of the callback which is called when a new image is available from {@link AImageReader}. 263 * 264 * @param context The optional application context provided by user in 265 * {@link AImageReader_setImageListener}. 266 * @param session The camera capture session whose state is changing. 267 */ 268 typedef void (*AImageReader_ImageCallback)(void* context, AImageReader* reader); 269 270 typedef struct AImageReader_ImageListener { 271 /// Optional application context passed as the first parameter of the callback. 272 void* context; 273 274 /** 275 * This callback is called when there is a new image available in the image reader's queue. 276 * 277 * <p>The callback happens on one dedicated thread per {@link AImageReader} instance. It is okay 278 * to use AImageReader_* and AImage_* methods within the callback. Note that it is possible that 279 * calling {@link AImageReader_acquireNextImage} or {@link AImageReader_acquireLatestImage} 280 * returns {@link AMEDIA_IMGREADER_NO_BUFFER_AVAILABLE} within this callback. For example, when 281 * there are multiple images and callbacks queued, if application called 282 * {@link AImageReader_acquireLatestImage}, some images will be returned to system before their 283 * corresponding callback is executed.</p> 284 */ 285 AImageReader_ImageCallback onImageAvailable; 286 } AImageReader_ImageListener; 287 288 /** 289 * Set the onImageAvailable listener of this image reader. 290 * 291 * Calling this method will replace previously registered listeners. 292 * 293 * @param reader The image reader of interest. 294 * @param listener The {@link AImageReader_ImageListener} to be registered. Set this to NULL if 295 * the application no longer needs to listen to new images. 296 * 297 * @return <ul> 298 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 299 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader is NULL.</li></ul> 300 */ 301 media_status_t AImageReader_setImageListener( 302 AImageReader* reader, AImageReader_ImageListener* listener) __INTRODUCED_IN(24); 303 304 #endif /* __ANDROID_API__ >= 24 */ 305 306 #if __ANDROID_API__ >= 26 307 308 /** 309 * AImageReader constructor similar to {@link AImageReader_new} that takes an additional parameter 310 * for the consumer usage. All other parameters and the return values are identical to those passed 311 * to {@link AImageReader_new}. 312 * 313 * <p>If the \c format is {@link AIMAGE_FORMAT_PRIVATE}, the created {@link AImageReader} 314 * will produce images whose contents are not directly accessible by the application. The application can 315 * still acquire images from this {@link AImageReader} and access {@link AHardwareBuffer} via 316 * {@link AImage_getHardwareBuffer()}. The {@link AHardwareBuffer} gained this way can then 317 * be passed back to hardware (such as GPU or hardware encoder if supported) for future processing. 318 * For example, you can obtain an {@link EGLClientBuffer} from the {@link AHardwareBuffer} by using 319 * {@link eglGetNativeClientBufferANDROID} extension and pass that {@link EGLClientBuffer} to {@link 320 * eglCreateImageKHR} to create an {@link EGLImage} resource type, which may then be bound to a 321 * texture via {@link glEGLImageTargetTexture2DOES} on supported devices. This can be useful for 322 * transporting textures that may be shared cross-process.</p> 323 * <p>In general, when software access to image data is not necessary, an {@link AImageReader} 324 * created with {@link AIMAGE_FORMAT_PRIVATE} format is more efficient, compared with {@link 325 * AImageReader}s using other format such as {@link AIMAGE_FORMAT_YUV_420_888}.</p> 326 * 327 * <p>Note that not all format and usage flag combination is supported by the {@link AImageReader}, 328 * especially if \c format is {@link AIMAGE_FORMAT_PRIVATE}, \c usage must not include either 329 * {@link AHARDWAREBUFFER_USAGE_READ_RARELY} or {@link AHARDWAREBUFFER_USAGE_READ_OFTEN}</p> 330 * 331 * @param width The default width in pixels of the Images that this reader will produce. 332 * @param height The default height in pixels of the Images that this reader will produce. 333 * @param format The format of the Image that this reader will produce. This must be one of the 334 * AIMAGE_FORMAT_* enum value defined in {@link AIMAGE_FORMATS}. 335 * @param usage specifies how the consumer will access the AImage, using combination of the 336 * AHARDWAREBUFFER_USAGE flags described in {@link hardware_buffer.h}. 337 * Passing {@link AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN} is equivalent to calling 338 * {@link AImageReader_new} with the same parameters. 339 * 340 * Note that not all format and usage flag combination is supported by the {@link AImageReader}. 341 * Below are the combinations supported by the {@link AImageReader}. 342 * <table> 343 * <tr> 344 * <th>Format</th> 345 * <th>Compatible usage flags</th> 346 * </tr> 347 * <tr> 348 * <td>non-{@link AIMAGE_FORMAT_PRIVATE PRIVATE} formats defined in {@link AImage.h} 349 * </td> 350 * <td>{@link AHARDWAREBUFFER_USAGE_CPU_READ_RARELY} or 351 * {@link AHARDWAREBUFFER_USAGE_CPU_READ_OFTEN}</td> 352 * </tr> 353 * <tr> 354 * <td>{@link AIMAGE_FORMAT_RGBA_8888}</td> 355 * <td>{@link AHARDWAREBUFFER_USAGE_VIDEO_ENCODE} or 356 * {@link AHARDWAREBUFFER_USAGE_GPU_SAMPLED_IMAGE}, or combined</td> 357 * </tr> 358 * </table> 359 * @return <ul> 360 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 361 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader is NULL, or one or more of width, 362 * height, format, maxImages, or usage arguments is not supported.</li> 363 * <li>{@link AMEDIA_ERROR_UNKNOWN} if the method fails for some other reasons.</li></ul> 364 * 365 * @see AImage 366 * @see AImageReader_new 367 * @see AHardwareBuffer 368 */ 369 media_status_t AImageReader_newWithUsage( 370 int32_t width, int32_t height, int32_t format, uint64_t usage, int32_t maxImages, 371 /*out*/ AImageReader** reader) __INTRODUCED_IN(26); 372 373 /** 374 * Acquire the next {@link AImage} from the image reader's queue asynchronously. 375 * 376 * <p>AImageReader acquire method similar to {@link AImageReader_acquireNextImage} that takes an 377 * additional parameter for the sync fence. All other parameters and the return values are 378 * identical to those passed to {@link AImageReader_acquireNextImage}.</p> 379 * 380 * @param acquireFenceFd A sync fence fd defined in {@link sync.h}, which is used to signal when the 381 * buffer is ready to consume. When synchronization fence is not needed, fence will be set 382 * to -1 and the {@link AImage} returned is ready for use immediately. Otherwise, user shall 383 * use syscalls such as \c poll(), \c epoll(), \c select() to wait for the 384 * fence fd to change status before attempting to access the {@link AImage} returned. 385 * 386 * @see sync.h 387 * @see sync_get_fence_info 388 */ 389 media_status_t AImageReader_acquireNextImageAsync( 390 AImageReader* reader, /*out*/AImage** image, /*out*/int* acquireFenceFd) __INTRODUCED_IN(26); 391 392 /** 393 * Acquire the latest {@link AImage} from the image reader's queue asynchronously, dropping older 394 * images. 395 * 396 * <p>AImageReader acquire method similar to {@link AImageReader_acquireLatestImage} that takes an 397 * additional parameter for the sync fence. All other parameters and the return values are 398 * identical to those passed to {@link AImageReader_acquireLatestImage}.</p> 399 * 400 * @param acquireFenceFd A sync fence fd defined in {@link sync.h}, which is used to signal when the 401 * buffer is ready to consume. When synchronization fence is not needed, fence will be set 402 * to -1 and the {@link AImage} returned is ready for use immediately. Otherwise, user shall 403 * use syscalls such as \c poll(), \c epoll(), \c select() to wait for the 404 * fence fd to change status before attempting to access the {@link AImage} returned. 405 * 406 * @see sync.h 407 * @see sync_get_fence_info 408 */ 409 media_status_t AImageReader_acquireLatestImageAsync( 410 AImageReader* reader, /*out*/AImage** image, /*out*/int* acquireFenceFd) __INTRODUCED_IN(26); 411 /** 412 * Signature of the callback which is called when {@link AImageReader} is about to remove a buffer. 413 * 414 * @param context The optional application context provided by user in 415 * {@link AImageReader_setBufferRemovedListener}. 416 * @param reader The {@link AImageReader} of interest. 417 * @param buffer The {@link AHardwareBuffer} that is being removed from this image reader. 418 */ 419 typedef void (*AImageReader_BufferRemovedCallback)(void* context, 420 AImageReader* reader, 421 AHardwareBuffer* buffer); 422 423 typedef struct AImageReader_BufferRemovedListener { 424 /// Optional application context passed as the first parameter of the callback. 425 void* context; 426 427 /** 428 * This callback is called when an old {@link AHardwareBuffer} is about to be removed from the 429 * image reader. 430 * 431 * <p>Note that registering this callback is optional unless the user holds on extra reference 432 * to {@link AHardwareBuffer} returned from {@link AImage_getHardwareBuffer} by calling {@link 433 * AHardwareBuffer_acquire} or creating external graphic objects, such as EglImage, from it.</p> 434 * 435 * <p>If the callback is registered, the {@link AImageReader} will hold on the last of its 436 * references to the {@link AHardwareBuffer} until this callback returns. User can use the 437 * callback to get notified that it becomes the last owner of the buffer. It is up to the user 438 * to decide to either 1) immediately release all of its references to the buffer; or 2) keep 439 * using the buffer and release it in future. Note that, if option 2 if used, user of this API 440 * is responsible to deallocate the buffer properly by calling {@link AHardwareBuffer_release}. 441 * </p> 442 * 443 * @see AHardwareBuffer_release 444 * @see AImage_getHardwareBuffer 445 */ 446 AImageReader_BufferRemovedCallback onBufferRemoved; 447 } AImageReader_BufferRemovedListener; 448 449 /** 450 * Set the onBufferRemoved listener of this image reader. 451 * 452 * <p>Note that calling this method will replace previously registered listeners.</p> 453 * 454 * @param reader The image reader of interest. 455 * @param listener the {@link AImageReader_BufferRemovedListener} to be registered. Set this to 456 * NULL if application no longer needs to listen to buffer removed events. 457 * 458 * @return <ul> 459 * <li>{@link AMEDIA_OK} if the method call succeeds.</li> 460 * <li>{@link AMEDIA_ERROR_INVALID_PARAMETER} if reader is NULL.</li></ul> 461 * 462 * @see AImage_getHardwareBuffer 463 */ 464 media_status_t AImageReader_setBufferRemovedListener( 465 AImageReader* reader, AImageReader_BufferRemovedListener* listener) __INTRODUCED_IN(26); 466 467 #ifdef __ANDROID_VNDK__ 468 /* 469 * Get the native_handle_t corresponding to the ANativeWindow owned by the 470 * AImageReader provided. 471 * 472 * @param reader The image reader of interest. 473 * @param handle The output native_handle_t. This native handle is owned by 474 * this image reader. 475 * 476 * @return AMEDIA_OK if the method call succeeds. 477 * AMEDIA_ERROR_INVALID_PARAMETER if reader or handle are NULL. 478 * AMEDIA_ERROR_UNKNOWN if some other error is encountered. 479 */ 480 media_status_t AImageReader_getWindowNativeHandle( 481 AImageReader *reader, /* out */native_handle_t **handle); 482 #endif 483 484 #endif /* __ANDROID_API__ >= 26 */ 485 486 __END_DECLS 487 488 #endif //_NDK_IMAGE_READER_H 489 490 /** @} */ 491