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