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| 1 /* | |
| 2 * Copyright 2016 The WebRTC project authors. All Rights Reserved. | |
| 3 * | |
| 4 * Use of this source code is governed by a BSD-style license | |
| 5 * that can be found in the LICENSE file in the root of the source | |
| 6 * tree. An additional intellectual property rights grant can be found | |
| 7 * in the file PATENTS. All contributing project authors may | |
| 8 * be found in the AUTHORS file in the root of the source tree. | |
| 9 */ | |
| 10 | |
| 11 #import "RTCAVFoundationVideoCapturerInternal.h" | |
| 12 | |
| 13 #import <Foundation/Foundation.h> | |
| 14 #if TARGET_OS_IPHONE | |
| 15 #import <UIKit/UIKit.h> | |
| 16 #import "WebRTC/UIDevice+RTCDevice.h" | |
| 17 #endif | |
| 18 | |
| 19 #import "RTCDispatcher+Private.h" | |
| 20 #import "WebRTC/RTCLogging.h" | |
| 21 | |
| 22 #include "avfoundationformatmapper.h" | |
| 23 | |
| 24 @implementation RTCAVFoundationVideoCapturerInternal { | |
| 25 // Keep pointers to inputs for convenience. | |
| 26 AVCaptureDeviceInput *_frontCameraInput; | |
| 27 AVCaptureDeviceInput *_backCameraInput; | |
| 28 AVCaptureVideoDataOutput *_videoDataOutput; | |
| 29 // The cricket::VideoCapturer that owns this class. Should never be NULL. | |
| 30 webrtc::AVFoundationVideoCapturer *_capturer; | |
| 31 webrtc::VideoRotation _rotation; | |
| 32 BOOL _hasRetriedOnFatalError; | |
| 33 BOOL _isRunning; | |
| 34 BOOL _hasStarted; | |
| 35 rtc::CriticalSection _crit; | |
| 36 } | |
| 37 | |
| 38 @synthesize captureSession = _captureSession; | |
| 39 @synthesize frameQueue = _frameQueue; | |
| 40 @synthesize useBackCamera = _useBackCamera; | |
| 41 | |
| 42 @synthesize isRunning = _isRunning; | |
| 43 @synthesize hasStarted = _hasStarted; | |
| 44 | |
| 45 // This is called from the thread that creates the video source, which is likely | |
| 46 // the main thread. | |
| 47 - (instancetype)initWithCapturer:(webrtc::AVFoundationVideoCapturer *)capturer { | |
| 48 RTC_DCHECK(capturer); | |
| 49 if (self = [super init]) { | |
| 50 _capturer = capturer; | |
| 51 // Create the capture session and all relevant inputs and outputs. We need | |
| 52 // to do this in init because the application may want the capture session | |
| 53 // before we start the capturer for e.g. AVCapturePreviewLayer. All objects | |
| 54 // created here are retained until dealloc and never recreated. | |
| 55 if (![self setupCaptureSession]) { | |
| 56 return nil; | |
| 57 } | |
| 58 NSNotificationCenter *center = [NSNotificationCenter defaultCenter]; | |
| 59 #if TARGET_OS_IPHONE | |
| 60 [center addObserver:self | |
| 61 selector:@selector(deviceOrientationDidChange:) | |
| 62 name:UIDeviceOrientationDidChangeNotification | |
| 63 object:nil]; | |
| 64 [center addObserver:self | |
| 65 selector:@selector(handleCaptureSessionInterruption:) | |
| 66 name:AVCaptureSessionWasInterruptedNotification | |
| 67 object:_captureSession]; | |
| 68 [center addObserver:self | |
| 69 selector:@selector(handleCaptureSessionInterruptionEnded:) | |
| 70 name:AVCaptureSessionInterruptionEndedNotification | |
| 71 object:_captureSession]; | |
| 72 [center addObserver:self | |
| 73 selector:@selector(handleApplicationDidBecomeActive:) | |
| 74 name:UIApplicationDidBecomeActiveNotification | |
| 75 object:[UIApplication sharedApplication]]; | |
| 76 #endif | |
| 77 [center addObserver:self | |
| 78 selector:@selector(handleCaptureSessionRuntimeError:) | |
| 79 name:AVCaptureSessionRuntimeErrorNotification | |
| 80 object:_captureSession]; | |
| 81 [center addObserver:self | |
| 82 selector:@selector(handleCaptureSessionDidStartRunning:) | |
| 83 name:AVCaptureSessionDidStartRunningNotification | |
| 84 object:_captureSession]; | |
| 85 [center addObserver:self | |
| 86 selector:@selector(handleCaptureSessionDidStopRunning:) | |
| 87 name:AVCaptureSessionDidStopRunningNotification | |
| 88 object:_captureSession]; | |
| 89 } | |
| 90 return self; | |
| 91 } | |
| 92 | |
| 93 - (void)dealloc { | |
| 94 RTC_DCHECK(!self.hasStarted); | |
| 95 [[NSNotificationCenter defaultCenter] removeObserver:self]; | |
| 96 _capturer = nullptr; | |
| 97 } | |
| 98 | |
| 99 - (AVCaptureSession *)captureSession { | |
| 100 return _captureSession; | |
| 101 } | |
| 102 | |
| 103 - (AVCaptureDevice *)getActiveCaptureDevice { | |
| 104 return self.useBackCamera ? _backCameraInput.device : _frontCameraInput.device
; | |
| 105 } | |
| 106 | |
| 107 - (nullable AVCaptureDevice *)frontCaptureDevice { | |
| 108 return _frontCameraInput.device; | |
| 109 } | |
| 110 | |
| 111 - (nullable AVCaptureDevice *)backCaptureDevice { | |
| 112 return _backCameraInput.device; | |
| 113 } | |
| 114 | |
| 115 - (dispatch_queue_t)frameQueue { | |
| 116 if (!_frameQueue) { | |
| 117 _frameQueue = | |
| 118 dispatch_queue_create("org.webrtc.avfoundationvideocapturer.video", DISP
ATCH_QUEUE_SERIAL); | |
| 119 dispatch_set_target_queue(_frameQueue, | |
| 120 dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_
HIGH, 0)); | |
| 121 } | |
| 122 return _frameQueue; | |
| 123 } | |
| 124 | |
| 125 // Called from any thread (likely main thread). | |
| 126 - (BOOL)canUseBackCamera { | |
| 127 return _backCameraInput != nil; | |
| 128 } | |
| 129 | |
| 130 // Called from any thread (likely main thread). | |
| 131 - (BOOL)useBackCamera { | |
| 132 @synchronized(self) { | |
| 133 return _useBackCamera; | |
| 134 } | |
| 135 } | |
| 136 | |
| 137 // Called from any thread (likely main thread). | |
| 138 - (void)setUseBackCamera:(BOOL)useBackCamera { | |
| 139 if (!self.canUseBackCamera) { | |
| 140 if (useBackCamera) { | |
| 141 RTCLogWarning(@"No rear-facing camera exists or it cannot be used;" | |
| 142 "not switching."); | |
| 143 } | |
| 144 return; | |
| 145 } | |
| 146 @synchronized(self) { | |
| 147 if (_useBackCamera == useBackCamera) { | |
| 148 return; | |
| 149 } | |
| 150 _useBackCamera = useBackCamera; | |
| 151 [self updateSessionInputForUseBackCamera:useBackCamera]; | |
| 152 } | |
| 153 } | |
| 154 | |
| 155 // Called from WebRTC thread. | |
| 156 - (void)start { | |
| 157 if (self.hasStarted) { | |
| 158 return; | |
| 159 } | |
| 160 self.hasStarted = YES; | |
| 161 [RTCDispatcher | |
| 162 dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 163 block:^{ | |
| 164 #if TARGET_OS_IPHONE | |
| 165 // Default to portrait orientation on iPhone. This will
be reset in | |
| 166 // updateOrientation unless orientation is unknown/faceu
p/facedown. | |
| 167 _rotation = webrtc::kVideoRotation_90; | |
| 168 #else | |
| 169 // No rotation on Mac. | |
| 170 _rotation = webrtc::kVideoRotation_0; | |
| 171 #endif | |
| 172 [self updateOrientation]; | |
| 173 #if TARGET_OS_IPHONE | |
| 174 [[UIDevice currentDevice] beginGeneratingDeviceOrientati
onNotifications]; | |
| 175 #endif | |
| 176 AVCaptureSession *captureSession = self.captureSession; | |
| 177 [captureSession startRunning]; | |
| 178 }]; | |
| 179 } | |
| 180 | |
| 181 // Called from same thread as start. | |
| 182 - (void)stop { | |
| 183 if (!self.hasStarted) { | |
| 184 return; | |
| 185 } | |
| 186 self.hasStarted = NO; | |
| 187 // Due to this async block, it's possible that the ObjC object outlives the | |
| 188 // C++ one. In order to not invoke functions on the C++ object, we set | |
| 189 // hasStarted immediately instead of dispatching it async. | |
| 190 [RTCDispatcher | |
| 191 dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 192 block:^{ | |
| 193 [_videoDataOutput setSampleBufferDelegate:nil queue:null
ptr]; | |
| 194 [_captureSession stopRunning]; | |
| 195 #if TARGET_OS_IPHONE | |
| 196 [[UIDevice currentDevice] endGeneratingDeviceOrientation
Notifications]; | |
| 197 #endif | |
| 198 }]; | |
| 199 } | |
| 200 | |
| 201 #pragma mark iOS notifications | |
| 202 | |
| 203 #if TARGET_OS_IPHONE | |
| 204 - (void)deviceOrientationDidChange:(NSNotification *)notification { | |
| 205 [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 206 block:^{ | |
| 207 [self updateOrientation]; | |
| 208 }]; | |
| 209 } | |
| 210 #endif | |
| 211 | |
| 212 #pragma mark AVCaptureVideoDataOutputSampleBufferDelegate | |
| 213 | |
| 214 - (void)captureOutput:(AVCaptureOutput *)captureOutput | |
| 215 didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer | |
| 216 fromConnection:(AVCaptureConnection *)connection { | |
| 217 NSParameterAssert(captureOutput == _videoDataOutput); | |
| 218 if (!self.hasStarted) { | |
| 219 return; | |
| 220 } | |
| 221 _capturer->CaptureSampleBuffer(sampleBuffer, _rotation); | |
| 222 } | |
| 223 | |
| 224 - (void)captureOutput:(AVCaptureOutput *)captureOutput | |
| 225 didDropSampleBuffer:(CMSampleBufferRef)sampleBuffer | |
| 226 fromConnection:(AVCaptureConnection *)connection { | |
| 227 RTCLogError(@"Dropped sample buffer."); | |
| 228 } | |
| 229 | |
| 230 #pragma mark - AVCaptureSession notifications | |
| 231 | |
| 232 - (void)handleCaptureSessionInterruption:(NSNotification *)notification { | |
| 233 NSString *reasonString = nil; | |
| 234 #if defined(__IPHONE_9_0) && defined(__IPHONE_OS_VERSION_MAX_ALLOWED) && \ | |
| 235 __IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_9_0 | |
| 236 if ([UIDevice isIOS9OrLater]) { | |
| 237 NSNumber *reason = notification.userInfo[AVCaptureSessionInterruptionReasonK
ey]; | |
| 238 if (reason) { | |
| 239 switch (reason.intValue) { | |
| 240 case AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableInBackgrou
nd: | |
| 241 reasonString = @"VideoDeviceNotAvailableInBackground"; | |
| 242 break; | |
| 243 case AVCaptureSessionInterruptionReasonAudioDeviceInUseByAnotherClient: | |
| 244 reasonString = @"AudioDeviceInUseByAnotherClient"; | |
| 245 break; | |
| 246 case AVCaptureSessionInterruptionReasonVideoDeviceInUseByAnotherClient: | |
| 247 reasonString = @"VideoDeviceInUseByAnotherClient"; | |
| 248 break; | |
| 249 case AVCaptureSessionInterruptionReasonVideoDeviceNotAvailableWithMultip
leForegroundApps: | |
| 250 reasonString = @"VideoDeviceNotAvailableWithMultipleForegroundApps"; | |
| 251 break; | |
| 252 } | |
| 253 } | |
| 254 } | |
| 255 #endif | |
| 256 RTCLog(@"Capture session interrupted: %@", reasonString); | |
| 257 // TODO(tkchin): Handle this case. | |
| 258 } | |
| 259 | |
| 260 - (void)handleCaptureSessionInterruptionEnded:(NSNotification *)notification { | |
| 261 RTCLog(@"Capture session interruption ended."); | |
| 262 // TODO(tkchin): Handle this case. | |
| 263 } | |
| 264 | |
| 265 - (void)handleCaptureSessionRuntimeError:(NSNotification *)notification { | |
| 266 NSError *error = [notification.userInfo objectForKey:AVCaptureSessionErrorKey]
; | |
| 267 RTCLogError(@"Capture session runtime error: %@", error); | |
| 268 | |
| 269 [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 270 block:^{ | |
| 271 #if TARGET_OS_IPHONE | |
| 272 if (error.code == AVErrorMediaServicesWereRes
et) { | |
| 273 [self handleNonFatalError]; | |
| 274 } else { | |
| 275 [self handleFatalError]; | |
| 276 } | |
| 277 #else | |
| 278 [self handleFatalError]; | |
| 279 #endif | |
| 280 }]; | |
| 281 } | |
| 282 | |
| 283 - (void)handleCaptureSessionDidStartRunning:(NSNotification *)notification { | |
| 284 RTCLog(@"Capture session started."); | |
| 285 | |
| 286 self.isRunning = YES; | |
| 287 [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 288 block:^{ | |
| 289 // If we successfully restarted after an unkn
own error, | |
| 290 // allow future retries on fatal errors. | |
| 291 _hasRetriedOnFatalError = NO; | |
| 292 }]; | |
| 293 } | |
| 294 | |
| 295 - (void)handleCaptureSessionDidStopRunning:(NSNotification *)notification { | |
| 296 RTCLog(@"Capture session stopped."); | |
| 297 self.isRunning = NO; | |
| 298 } | |
| 299 | |
| 300 - (void)handleFatalError { | |
| 301 [RTCDispatcher | |
| 302 dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 303 block:^{ | |
| 304 if (!_hasRetriedOnFatalError) { | |
| 305 RTCLogWarning(@"Attempting to recover from fatal captu
re error."); | |
| 306 [self handleNonFatalError]; | |
| 307 _hasRetriedOnFatalError = YES; | |
| 308 } else { | |
| 309 RTCLogError(@"Previous fatal error recovery failed."); | |
| 310 } | |
| 311 }]; | |
| 312 } | |
| 313 | |
| 314 - (void)handleNonFatalError { | |
| 315 [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 316 block:^{ | |
| 317 if (self.hasStarted) { | |
| 318 RTCLog(@"Restarting capture session after e
rror."); | |
| 319 [self.captureSession startRunning]; | |
| 320 } | |
| 321 }]; | |
| 322 } | |
| 323 | |
| 324 #if TARGET_OS_IPHONE | |
| 325 | |
| 326 #pragma mark - UIApplication notifications | |
| 327 | |
| 328 - (void)handleApplicationDidBecomeActive:(NSNotification *)notification { | |
| 329 [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 330 block:^{ | |
| 331 if (self.hasStarted && !self.captureSession.i
sRunning) { | |
| 332 RTCLog(@"Restarting capture session on acti
ve."); | |
| 333 [self.captureSession startRunning]; | |
| 334 } | |
| 335 }]; | |
| 336 } | |
| 337 | |
| 338 #endif // TARGET_OS_IPHONE | |
| 339 | |
| 340 #pragma mark - Private | |
| 341 | |
| 342 - (BOOL)setupCaptureSession { | |
| 343 AVCaptureSession *captureSession = [[AVCaptureSession alloc] init]; | |
| 344 #if defined(WEBRTC_IOS) | |
| 345 captureSession.usesApplicationAudioSession = NO; | |
| 346 #endif | |
| 347 // Add the output. | |
| 348 AVCaptureVideoDataOutput *videoDataOutput = [self videoDataOutput]; | |
| 349 if (![captureSession canAddOutput:videoDataOutput]) { | |
| 350 RTCLogError(@"Video data output unsupported."); | |
| 351 return NO; | |
| 352 } | |
| 353 [captureSession addOutput:videoDataOutput]; | |
| 354 | |
| 355 // Get the front and back cameras. If there isn't a front camera | |
| 356 // give up. | |
| 357 AVCaptureDeviceInput *frontCameraInput = [self frontCameraInput]; | |
| 358 AVCaptureDeviceInput *backCameraInput = [self backCameraInput]; | |
| 359 if (!frontCameraInput) { | |
| 360 RTCLogError(@"No front camera for capture session."); | |
| 361 return NO; | |
| 362 } | |
| 363 | |
| 364 // Add the inputs. | |
| 365 if (![captureSession canAddInput:frontCameraInput] || | |
| 366 (backCameraInput && ![captureSession canAddInput:backCameraInput])) { | |
| 367 RTCLogError(@"Session does not support capture inputs."); | |
| 368 return NO; | |
| 369 } | |
| 370 AVCaptureDeviceInput *input = self.useBackCamera ? backCameraInput : frontCame
raInput; | |
| 371 [captureSession addInput:input]; | |
| 372 | |
| 373 _captureSession = captureSession; | |
| 374 return YES; | |
| 375 } | |
| 376 | |
| 377 - (AVCaptureVideoDataOutput *)videoDataOutput { | |
| 378 if (!_videoDataOutput) { | |
| 379 // Make the capturer output NV12. Ideally we want I420 but that's not | |
| 380 // currently supported on iPhone / iPad. | |
| 381 AVCaptureVideoDataOutput *videoDataOutput = [[AVCaptureVideoDataOutput alloc
] init]; | |
| 382 videoDataOutput.videoSettings = @{ | |
| 383 (NSString *) | |
| 384 // TODO(denicija): Remove this color conversion and use the original captu
re format directly. | |
| 385 kCVPixelBufferPixelFormatTypeKey : @(kCVPixelFormatType_420YpCbCr8BiPlanar
FullRange) | |
| 386 }; | |
| 387 videoDataOutput.alwaysDiscardsLateVideoFrames = NO; | |
| 388 [videoDataOutput setSampleBufferDelegate:self queue:self.frameQueue]; | |
| 389 _videoDataOutput = videoDataOutput; | |
| 390 } | |
| 391 return _videoDataOutput; | |
| 392 } | |
| 393 | |
| 394 - (AVCaptureDevice *)videoCaptureDeviceForPosition:(AVCaptureDevicePosition)posi
tion { | |
| 395 for (AVCaptureDevice *captureDevice in [AVCaptureDevice devicesWithMediaType:A
VMediaTypeVideo]) { | |
| 396 if (captureDevice.position == position) { | |
| 397 return captureDevice; | |
| 398 } | |
| 399 } | |
| 400 return nil; | |
| 401 } | |
| 402 | |
| 403 - (AVCaptureDeviceInput *)frontCameraInput { | |
| 404 if (!_frontCameraInput) { | |
| 405 #if TARGET_OS_IPHONE | |
| 406 AVCaptureDevice *frontCameraDevice = | |
| 407 [self videoCaptureDeviceForPosition:AVCaptureDevicePositionFront]; | |
| 408 #else | |
| 409 AVCaptureDevice *frontCameraDevice = | |
| 410 [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo]; | |
| 411 #endif | |
| 412 if (!frontCameraDevice) { | |
| 413 RTCLogWarning(@"Failed to find front capture device."); | |
| 414 return nil; | |
| 415 } | |
| 416 NSError *error = nil; | |
| 417 AVCaptureDeviceInput *frontCameraInput = | |
| 418 [AVCaptureDeviceInput deviceInputWithDevice:frontCameraDevice error:&err
or]; | |
| 419 if (!frontCameraInput) { | |
| 420 RTCLogError(@"Failed to create front camera input: %@", error.localizedDes
cription); | |
| 421 return nil; | |
| 422 } | |
| 423 _frontCameraInput = frontCameraInput; | |
| 424 } | |
| 425 return _frontCameraInput; | |
| 426 } | |
| 427 | |
| 428 - (AVCaptureDeviceInput *)backCameraInput { | |
| 429 if (!_backCameraInput) { | |
| 430 AVCaptureDevice *backCameraDevice = | |
| 431 [self videoCaptureDeviceForPosition:AVCaptureDevicePositionBack]; | |
| 432 if (!backCameraDevice) { | |
| 433 RTCLogWarning(@"Failed to find front capture device."); | |
| 434 return nil; | |
| 435 } | |
| 436 NSError *error = nil; | |
| 437 AVCaptureDeviceInput *backCameraInput = | |
| 438 [AVCaptureDeviceInput deviceInputWithDevice:backCameraDevice error:&erro
r]; | |
| 439 if (!backCameraInput) { | |
| 440 RTCLogError(@"Failed to create front camera input: %@", error.localizedDes
cription); | |
| 441 return nil; | |
| 442 } | |
| 443 _backCameraInput = backCameraInput; | |
| 444 } | |
| 445 return _backCameraInput; | |
| 446 } | |
| 447 | |
| 448 // Called from capture session queue. | |
| 449 - (void)updateOrientation { | |
| 450 #if TARGET_OS_IPHONE | |
| 451 switch ([UIDevice currentDevice].orientation) { | |
| 452 case UIDeviceOrientationPortrait: | |
| 453 _rotation = webrtc::kVideoRotation_90; | |
| 454 break; | |
| 455 case UIDeviceOrientationPortraitUpsideDown: | |
| 456 _rotation = webrtc::kVideoRotation_270; | |
| 457 break; | |
| 458 case UIDeviceOrientationLandscapeLeft: | |
| 459 _rotation = | |
| 460 _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_0 : webrtc::kVi
deoRotation_180; | |
| 461 break; | |
| 462 case UIDeviceOrientationLandscapeRight: | |
| 463 _rotation = | |
| 464 _capturer->GetUseBackCamera() ? webrtc::kVideoRotation_180 : webrtc::k
VideoRotation_0; | |
| 465 break; | |
| 466 case UIDeviceOrientationFaceUp: | |
| 467 case UIDeviceOrientationFaceDown: | |
| 468 case UIDeviceOrientationUnknown: | |
| 469 // Ignore. | |
| 470 break; | |
| 471 } | |
| 472 #endif | |
| 473 } | |
| 474 | |
| 475 // Update the current session input to match what's stored in _useBackCamera. | |
| 476 - (void)updateSessionInputForUseBackCamera:(BOOL)useBackCamera { | |
| 477 [RTCDispatcher dispatchAsyncOnType:RTCDispatcherTypeCaptureSession | |
| 478 block:^{ | |
| 479 [_captureSession beginConfiguration]; | |
| 480 AVCaptureDeviceInput *oldInput = _backCameraI
nput; | |
| 481 AVCaptureDeviceInput *newInput = _frontCamera
Input; | |
| 482 if (useBackCamera) { | |
| 483 oldInput = _frontCameraInput; | |
| 484 newInput = _backCameraInput; | |
| 485 } | |
| 486 if (oldInput) { | |
| 487 // Ok to remove this even if it's not attac
hed. Will be no-op. | |
| 488 [_captureSession removeInput:oldInput]; | |
| 489 } | |
| 490 if (newInput) { | |
| 491 [_captureSession addInput:newInput]; | |
| 492 } | |
| 493 [self updateOrientation]; | |
| 494 AVCaptureDevice *newDevice = newInput.device; | |
| 495 const cricket::VideoFormat *format = | |
| 496 _capturer->GetCaptureFormat(); | |
| 497 webrtc::SetFormatForCaptureDevice( | |
| 498 newDevice, _captureSession, *format); | |
| 499 [_captureSession commitConfiguration]; | |
| 500 }]; | |
| 501 } | |
| 502 | |
| 503 @end | |
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