1 /* 2 * Copyright 2014 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 package com.example.android.camera2basic; 18 19 import android.app.Activity; 20 import android.app.AlertDialog; 21 import android.app.Dialog; 22 import android.app.DialogFragment; 23 import android.app.Fragment; 24 import android.content.Context; 25 import android.content.DialogInterface; 26 import android.content.res.Configuration; 27 import android.graphics.ImageFormat; 28 import android.graphics.Matrix; 29 import android.graphics.RectF; 30 import android.graphics.SurfaceTexture; 31 import android.hardware.camera2.CameraAccessException; 32 import android.hardware.camera2.CameraCaptureSession; 33 import android.hardware.camera2.CameraCharacteristics; 34 import android.hardware.camera2.CameraDevice; 35 import android.hardware.camera2.CameraManager; 36 import android.hardware.camera2.CameraMetadata; 37 import android.hardware.camera2.CaptureRequest; 38 import android.hardware.camera2.CaptureResult; 39 import android.hardware.camera2.TotalCaptureResult; 40 import android.hardware.camera2.params.StreamConfigurationMap; 41 import android.media.Image; 42 import android.media.ImageReader; 43 import android.os.Bundle; 44 import android.os.Handler; 45 import android.os.HandlerThread; 46 import android.os.Message; 47 import android.util.Log; 48 import android.util.Size; 49 import android.util.SparseIntArray; 50 import android.view.LayoutInflater; 51 import android.view.Surface; 52 import android.view.TextureView; 53 import android.view.View; 54 import android.view.ViewGroup; 55 import android.widget.Toast; 56 57 import java.io.File; 58 import java.io.FileNotFoundException; 59 import java.io.FileOutputStream; 60 import java.io.IOException; 61 import java.nio.ByteBuffer; 62 import java.util.ArrayList; 63 import java.util.Arrays; 64 import java.util.Collections; 65 import java.util.Comparator; 66 import java.util.List; 67 import java.util.concurrent.Semaphore; 68 import java.util.concurrent.TimeUnit; 69 70 public class Camera2BasicFragment extends Fragment implements View.OnClickListener { 71 72 /** 73 * Conversion from screen rotation to JPEG orientation. 74 */ 75 private static final SparseIntArray ORIENTATIONS = new SparseIntArray(); 76 77 static { 78 ORIENTATIONS.append(Surface.ROTATION_0, 90); 79 ORIENTATIONS.append(Surface.ROTATION_90, 0); 80 ORIENTATIONS.append(Surface.ROTATION_180, 270); 81 ORIENTATIONS.append(Surface.ROTATION_270, 180); 82 } 83 84 /** 85 * Tag for the {@link Log}. 86 */ 87 private static final String TAG = "Camera2BasicFragment"; 88 89 /** 90 * Camera state: Showing camera preview. 91 */ 92 private static final int STATE_PREVIEW = 0; 93 94 /** 95 * Camera state: Waiting for the focus to be locked. 96 */ 97 private static final int STATE_WAITING_LOCK = 1; 98 /** 99 * Camera state: Waiting for the exposure to be precapture state. 100 */ 101 private static final int STATE_WAITING_PRECAPTURE = 2; 102 /** 103 * Camera state: Waiting for the exposure state to be something other than precapture. 104 */ 105 private static final int STATE_WAITING_NON_PRECAPTURE = 3; 106 /** 107 * Camera state: Picture was taken. 108 */ 109 private static final int STATE_PICTURE_TAKEN = 4; 110 111 /** 112 * {@link TextureView.SurfaceTextureListener} handles several lifecycle events on a 113 * {@link TextureView}. 114 */ 115 private final TextureView.SurfaceTextureListener mSurfaceTextureListener 116 = new TextureView.SurfaceTextureListener() { 117 118 @Override 119 public void onSurfaceTextureAvailable(SurfaceTexture texture, int width, int height) { 120 openCamera(width, height); 121 } 122 123 @Override 124 public void onSurfaceTextureSizeChanged(SurfaceTexture texture, int width, int height) { 125 configureTransform(width, height); 126 } 127 128 @Override 129 public boolean onSurfaceTextureDestroyed(SurfaceTexture texture) { 130 return true; 131 } 132 133 @Override 134 public void onSurfaceTextureUpdated(SurfaceTexture texture) { 135 } 136 137 }; 138 139 /** 140 * ID of the current {@link CameraDevice}. 141 */ 142 private String mCameraId; 143 144 /** 145 * An {@link AutoFitTextureView} for camera preview. 146 */ 147 private AutoFitTextureView mTextureView; 148 149 /** 150 * A {@link CameraCaptureSession } for camera preview. 151 */ 152 153 private CameraCaptureSession mCaptureSession; 154 /** 155 * A reference to the opened {@link CameraDevice}. 156 */ 157 158 private CameraDevice mCameraDevice; 159 /** 160 * The {@link android.util.Size} of camera preview. 161 */ 162 163 private Size mPreviewSize; 164 165 /** 166 * {@link CameraDevice.StateCallback} is called when {@link CameraDevice} changes its state. 167 */ 168 private final CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() { 169 170 @Override 171 public void onOpened(CameraDevice cameraDevice) { 172 // This method is called when the camera is opened. We start camera preview here. 173 mCameraOpenCloseLock.release(); 174 mCameraDevice = cameraDevice; 175 createCameraPreviewSession(); 176 } 177 178 @Override 179 public void onDisconnected(CameraDevice cameraDevice) { 180 mCameraOpenCloseLock.release(); 181 cameraDevice.close(); 182 mCameraDevice = null; 183 } 184 185 @Override 186 public void onError(CameraDevice cameraDevice, int error) { 187 mCameraOpenCloseLock.release(); 188 cameraDevice.close(); 189 mCameraDevice = null; 190 Activity activity = getActivity(); 191 if (null != activity) { 192 activity.finish(); 193 } 194 } 195 196 }; 197 198 /** 199 * An additional thread for running tasks that shouldn't block the UI. 200 */ 201 private HandlerThread mBackgroundThread; 202 203 /** 204 * A {@link Handler} for running tasks in the background. 205 */ 206 private Handler mBackgroundHandler; 207 208 /** 209 * An {@link ImageReader} that handles still image capture. 210 */ 211 private ImageReader mImageReader; 212 213 /** 214 * This is the output file for our picture. 215 */ 216 private File mFile; 217 218 /** 219 * This a callback object for the {@link ImageReader}. "onImageAvailable" will be called when a 220 * still image is ready to be saved. 221 */ 222 private final ImageReader.OnImageAvailableListener mOnImageAvailableListener 223 = new ImageReader.OnImageAvailableListener() { 224 225 @Override 226 public void onImageAvailable(ImageReader reader) { 227 mBackgroundHandler.post(new ImageSaver(reader.acquireNextImage(), mFile)); 228 } 229 230 }; 231 232 /** 233 * {@link CaptureRequest.Builder} for the camera preview 234 */ 235 private CaptureRequest.Builder mPreviewRequestBuilder; 236 237 /** 238 * {@link CaptureRequest} generated by {@link #mPreviewRequestBuilder} 239 */ 240 private CaptureRequest mPreviewRequest; 241 242 /** 243 * The current state of camera state for taking pictures. 244 * 245 * @see #mCaptureCallback 246 */ 247 private int mState = STATE_PREVIEW; 248 249 /** 250 * A {@link Semaphore} to prevent the app from exiting before closing the camera. 251 */ 252 private Semaphore mCameraOpenCloseLock = new Semaphore(1); 253 254 /** 255 * A {@link CameraCaptureSession.CaptureCallback} that handles events related to JPEG capture. 256 */ 257 private CameraCaptureSession.CaptureCallback mCaptureCallback 258 = new CameraCaptureSession.CaptureCallback() { 259 260 private void process(CaptureResult result) { 261 switch (mState) { 262 case STATE_PREVIEW: { 263 // We have nothing to do when the camera preview is working normally. 264 break; 265 } 266 case STATE_WAITING_LOCK: { 267 int afState = result.get(CaptureResult.CONTROL_AF_STATE); 268 if (CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED == afState || 269 CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED == afState) { 270 // CONTROL_AE_STATE can be null on some devices 271 Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); 272 if (aeState == null || 273 aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) { 274 mState = STATE_WAITING_NON_PRECAPTURE; 275 captureStillPicture(); 276 } else { 277 runPrecaptureSequence(); 278 } 279 } 280 break; 281 } 282 case STATE_WAITING_PRECAPTURE: { 283 // CONTROL_AE_STATE can be null on some devices 284 Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); 285 if (aeState == null || 286 aeState == CaptureResult.CONTROL_AE_STATE_PRECAPTURE || 287 aeState == CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED) { 288 mState = STATE_WAITING_NON_PRECAPTURE; 289 } 290 break; 291 } 292 case STATE_WAITING_NON_PRECAPTURE: { 293 // CONTROL_AE_STATE can be null on some devices 294 Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); 295 if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) { 296 mState = STATE_PICTURE_TAKEN; 297 captureStillPicture(); 298 } 299 break; 300 } 301 } 302 } 303 304 @Override 305 public void onCaptureProgressed(CameraCaptureSession session, CaptureRequest request, 306 CaptureResult partialResult) { 307 process(partialResult); 308 } 309 310 @Override 311 public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request, 312 TotalCaptureResult result) { 313 process(result); 314 } 315 316 }; 317 318 /** 319 * A {@link Handler} for showing {@link Toast}s. 320 */ 321 private Handler mMessageHandler = new Handler() { 322 @Override 323 public void handleMessage(Message msg) { 324 Activity activity = getActivity(); 325 if (activity != null) { 326 Toast.makeText(activity, (String) msg.obj, Toast.LENGTH_SHORT).show(); 327 } 328 } 329 }; 330 331 /** 332 * Shows a {@link Toast} on the UI thread. 333 * 334 * @param text The message to show 335 */ 336 private void showToast(String text) { 337 // We show a Toast by sending request message to mMessageHandler. This makes sure that the 338 // Toast is shown on the UI thread. 339 Message message = Message.obtain(); 340 message.obj = text; 341 mMessageHandler.sendMessage(message); 342 } 343 344 /** 345 * Given {@code choices} of {@code Size}s supported by a camera, chooses the smallest one whose 346 * width and height are at least as large as the respective requested values, and whose aspect 347 * ratio matches with the specified value. 348 * 349 * @param choices The list of sizes that the camera supports for the intended output class 350 * @param width The minimum desired width 351 * @param height The minimum desired height 352 * @param aspectRatio The aspect ratio 353 * @return The optimal {@code Size}, or an arbitrary one if none were big enough 354 */ 355 private static Size chooseOptimalSize(Size[] choices, int width, int height, Size aspectRatio) { 356 // Collect the supported resolutions that are at least as big as the preview Surface 357 List<Size> bigEnough = new ArrayList<Size>(); 358 int w = aspectRatio.getWidth(); 359 int h = aspectRatio.getHeight(); 360 for (Size option : choices) { 361 if (option.getHeight() == option.getWidth() * h / w && 362 option.getWidth() >= width && option.getHeight() >= height) { 363 bigEnough.add(option); 364 } 365 } 366 367 // Pick the smallest of those, assuming we found any 368 if (bigEnough.size() > 0) { 369 return Collections.min(bigEnough, new CompareSizesByArea()); 370 } else { 371 Log.e(TAG, "Couldn't find any suitable preview size"); 372 return choices[0]; 373 } 374 } 375 376 public static Camera2BasicFragment newInstance() { 377 Camera2BasicFragment fragment = new Camera2BasicFragment(); 378 fragment.setRetainInstance(true); 379 return fragment; 380 } 381 382 @Override 383 public View onCreateView(LayoutInflater inflater, ViewGroup container, 384 Bundle savedInstanceState) { 385 return inflater.inflate(R.layout.fragment_camera2_basic, container, false); 386 } 387 388 @Override 389 public void onViewCreated(final View view, Bundle savedInstanceState) { 390 view.findViewById(R.id.picture).setOnClickListener(this); 391 view.findViewById(R.id.info).setOnClickListener(this); 392 mTextureView = (AutoFitTextureView) view.findViewById(R.id.texture); 393 } 394 395 @Override 396 public void onActivityCreated(Bundle savedInstanceState) { 397 super.onActivityCreated(savedInstanceState); 398 mFile = new File(getActivity().getExternalFilesDir(null), "pic.jpg"); 399 } 400 401 @Override 402 public void onResume() { 403 super.onResume(); 404 startBackgroundThread(); 405 406 // When the screen is turned off and turned back on, the SurfaceTexture is already 407 // available, and "onSurfaceTextureAvailable" will not be called. In that case, we can open 408 // a camera and start preview from here (otherwise, we wait until the surface is ready in 409 // the SurfaceTextureListener). 410 if (mTextureView.isAvailable()) { 411 openCamera(mTextureView.getWidth(), mTextureView.getHeight()); 412 } else { 413 mTextureView.setSurfaceTextureListener(mSurfaceTextureListener); 414 } 415 } 416 417 @Override 418 public void onPause() { 419 closeCamera(); 420 stopBackgroundThread(); 421 super.onPause(); 422 } 423 424 /** 425 * Sets up member variables related to camera. 426 * 427 * @param width The width of available size for camera preview 428 * @param height The height of available size for camera preview 429 */ 430 private void setUpCameraOutputs(int width, int height) { 431 Activity activity = getActivity(); 432 CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE); 433 try { 434 for (String cameraId : manager.getCameraIdList()) { 435 CameraCharacteristics characteristics 436 = manager.getCameraCharacteristics(cameraId); 437 438 // We don't use a front facing camera in this sample. 439 if (characteristics.get(CameraCharacteristics.LENS_FACING) 440 == CameraCharacteristics.LENS_FACING_FRONT) { 441 continue; 442 } 443 444 StreamConfigurationMap map = characteristics.get( 445 CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP); 446 447 // For still image captures, we use the largest available size. 448 Size largest = Collections.max( 449 Arrays.asList(map.getOutputSizes(ImageFormat.JPEG)), 450 new CompareSizesByArea()); 451 mImageReader = ImageReader.newInstance(largest.getWidth(), largest.getHeight(), 452 ImageFormat.JPEG, /*maxImages*/2); 453 mImageReader.setOnImageAvailableListener( 454 mOnImageAvailableListener, mBackgroundHandler); 455 456 // Danger, W.R.! Attempting to use too large a preview size could exceed the camera 457 // bus' bandwidth limitation, resulting in gorgeous previews but the storage of 458 // garbage capture data. 459 mPreviewSize = chooseOptimalSize(map.getOutputSizes(SurfaceTexture.class), 460 width, height, largest); 461 462 // We fit the aspect ratio of TextureView to the size of preview we picked. 463 int orientation = getResources().getConfiguration().orientation; 464 if (orientation == Configuration.ORIENTATION_LANDSCAPE) { 465 mTextureView.setAspectRatio( 466 mPreviewSize.getWidth(), mPreviewSize.getHeight()); 467 } else { 468 mTextureView.setAspectRatio( 469 mPreviewSize.getHeight(), mPreviewSize.getWidth()); 470 } 471 472 mCameraId = cameraId; 473 return; 474 } 475 } catch (CameraAccessException e) { 476 e.printStackTrace(); 477 } catch (NullPointerException e) { 478 // Currently an NPE is thrown when the Camera2API is used but not supported on the 479 // device this code runs. 480 new ErrorDialog().show(getFragmentManager(), "dialog"); 481 } 482 } 483 484 /** 485 * Opens the camera specified by {@link Camera2BasicFragment#mCameraId}. 486 */ 487 private void openCamera(int width, int height) { 488 setUpCameraOutputs(width, height); 489 configureTransform(width, height); 490 Activity activity = getActivity(); 491 CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE); 492 try { 493 if (!mCameraOpenCloseLock.tryAcquire(2500, TimeUnit.MILLISECONDS)) { 494 throw new RuntimeException("Time out waiting to lock camera opening."); 495 } 496 manager.openCamera(mCameraId, mStateCallback, mBackgroundHandler); 497 } catch (CameraAccessException e) { 498 e.printStackTrace(); 499 } catch (InterruptedException e) { 500 throw new RuntimeException("Interrupted while trying to lock camera opening.", e); 501 } 502 } 503 504 /** 505 * Closes the current {@link CameraDevice}. 506 */ 507 private void closeCamera() { 508 try { 509 mCameraOpenCloseLock.acquire(); 510 if (null != mCaptureSession) { 511 mCaptureSession.close(); 512 mCaptureSession = null; 513 } 514 if (null != mCameraDevice) { 515 mCameraDevice.close(); 516 mCameraDevice = null; 517 } 518 if (null != mImageReader) { 519 mImageReader.close(); 520 mImageReader = null; 521 } 522 } catch (InterruptedException e) { 523 throw new RuntimeException("Interrupted while trying to lock camera closing.", e); 524 } finally { 525 mCameraOpenCloseLock.release(); 526 } 527 } 528 529 /** 530 * Starts a background thread and its {@link Handler}. 531 */ 532 private void startBackgroundThread() { 533 mBackgroundThread = new HandlerThread("CameraBackground"); 534 mBackgroundThread.start(); 535 mBackgroundHandler = new Handler(mBackgroundThread.getLooper()); 536 } 537 538 /** 539 * Stops the background thread and its {@link Handler}. 540 */ 541 private void stopBackgroundThread() { 542 mBackgroundThread.quitSafely(); 543 try { 544 mBackgroundThread.join(); 545 mBackgroundThread = null; 546 mBackgroundHandler = null; 547 } catch (InterruptedException e) { 548 e.printStackTrace(); 549 } 550 } 551 552 /** 553 * Creates a new {@link CameraCaptureSession} for camera preview. 554 */ 555 private void createCameraPreviewSession() { 556 try { 557 SurfaceTexture texture = mTextureView.getSurfaceTexture(); 558 assert texture != null; 559 560 // We configure the size of default buffer to be the size of camera preview we want. 561 texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight()); 562 563 // This is the output Surface we need to start preview. 564 Surface surface = new Surface(texture); 565 566 // We set up a CaptureRequest.Builder with the output Surface. 567 mPreviewRequestBuilder 568 = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW); 569 mPreviewRequestBuilder.addTarget(surface); 570 571 // Here, we create a CameraCaptureSession for camera preview. 572 mCameraDevice.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()), 573 new CameraCaptureSession.StateCallback() { 574 575 @Override 576 public void onConfigured(CameraCaptureSession cameraCaptureSession) { 577 // The camera is already closed 578 if (null == mCameraDevice) { 579 return; 580 } 581 582 // When the session is ready, we start displaying the preview. 583 mCaptureSession = cameraCaptureSession; 584 try { 585 // Auto focus should be continuous for camera preview. 586 mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, 587 CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE); 588 // Flash is automatically enabled when necessary. 589 mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, 590 CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH); 591 592 // Finally, we start displaying the camera preview. 593 mPreviewRequest = mPreviewRequestBuilder.build(); 594 mCaptureSession.setRepeatingRequest(mPreviewRequest, 595 mCaptureCallback, mBackgroundHandler); 596 } catch (CameraAccessException e) { 597 e.printStackTrace(); 598 } 599 } 600 601 @Override 602 public void onConfigureFailed(CameraCaptureSession cameraCaptureSession) { 603 showToast("Failed"); 604 } 605 }, null 606 ); 607 } catch (CameraAccessException e) { 608 e.printStackTrace(); 609 } 610 } 611 612 /** 613 * Configures the necessary {@link android.graphics.Matrix} transformation to `mTextureView`. 614 * This method should be called after the camera preview size is determined in 615 * setUpCameraOutputs and also the size of `mTextureView` is fixed. 616 * 617 * @param viewWidth The width of `mTextureView` 618 * @param viewHeight The height of `mTextureView` 619 */ 620 private void configureTransform(int viewWidth, int viewHeight) { 621 Activity activity = getActivity(); 622 if (null == mTextureView || null == mPreviewSize || null == activity) { 623 return; 624 } 625 int rotation = activity.getWindowManager().getDefaultDisplay().getRotation(); 626 Matrix matrix = new Matrix(); 627 RectF viewRect = new RectF(0, 0, viewWidth, viewHeight); 628 RectF bufferRect = new RectF(0, 0, mPreviewSize.getHeight(), mPreviewSize.getWidth()); 629 float centerX = viewRect.centerX(); 630 float centerY = viewRect.centerY(); 631 if (Surface.ROTATION_90 == rotation || Surface.ROTATION_270 == rotation) { 632 bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY()); 633 matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL); 634 float scale = Math.max( 635 (float) viewHeight / mPreviewSize.getHeight(), 636 (float) viewWidth / mPreviewSize.getWidth()); 637 matrix.postScale(scale, scale, centerX, centerY); 638 matrix.postRotate(90 * (rotation - 2), centerX, centerY); 639 } 640 mTextureView.setTransform(matrix); 641 } 642 643 /** 644 * Initiate a still image capture. 645 */ 646 private void takePicture() { 647 lockFocus(); 648 } 649 650 /** 651 * Lock the focus as the first step for a still image capture. 652 */ 653 private void lockFocus() { 654 try { 655 // This is how to tell the camera to lock focus. 656 mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, 657 CameraMetadata.CONTROL_AF_TRIGGER_START); 658 // Tell #mCaptureCallback to wait for the lock. 659 mState = STATE_WAITING_LOCK; 660 mCaptureSession.setRepeatingRequest(mPreviewRequestBuilder.build(), mCaptureCallback, 661 mBackgroundHandler); 662 } catch (CameraAccessException e) { 663 e.printStackTrace(); 664 } 665 } 666 667 /** 668 * Run the precapture sequence for capturing a still image. This method should be called when we 669 * get a response in {@link #mCaptureCallback} from {@link #lockFocus()}. 670 */ 671 private void runPrecaptureSequence() { 672 try { 673 // This is how to tell the camera to trigger. 674 mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER, 675 CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER_START); 676 // Tell #mCaptureCallback to wait for the precapture sequence to be set. 677 mState = STATE_WAITING_PRECAPTURE; 678 mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback, 679 mBackgroundHandler); 680 } catch (CameraAccessException e) { 681 e.printStackTrace(); 682 } 683 } 684 685 /** 686 * Capture a still picture. This method should be called when we get a response in 687 * {@link #mCaptureCallback} from both {@link #lockFocus()}. 688 */ 689 private void captureStillPicture() { 690 try { 691 final Activity activity = getActivity(); 692 if (null == activity || null == mCameraDevice) { 693 return; 694 } 695 // This is the CaptureRequest.Builder that we use to take a picture. 696 final CaptureRequest.Builder captureBuilder = 697 mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE); 698 captureBuilder.addTarget(mImageReader.getSurface()); 699 700 // Use the same AE and AF modes as the preview. 701 captureBuilder.set(CaptureRequest.CONTROL_AF_MODE, 702 CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE); 703 captureBuilder.set(CaptureRequest.CONTROL_AE_MODE, 704 CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH); 705 706 // Orientation 707 int rotation = activity.getWindowManager().getDefaultDisplay().getRotation(); 708 captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, ORIENTATIONS.get(rotation)); 709 710 CameraCaptureSession.CaptureCallback CaptureCallback 711 = new CameraCaptureSession.CaptureCallback() { 712 713 @Override 714 public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request, 715 TotalCaptureResult result) { 716 showToast("Saved: " + mFile); 717 unlockFocus(); 718 } 719 }; 720 721 mCaptureSession.stopRepeating(); 722 mCaptureSession.capture(captureBuilder.build(), CaptureCallback, null); 723 } catch (CameraAccessException e) { 724 e.printStackTrace(); 725 } 726 } 727 728 /** 729 * Unlock the focus. This method should be called when still image capture sequence is finished. 730 */ 731 private void unlockFocus() { 732 try { 733 // Reset the autofucos trigger 734 mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, 735 CameraMetadata.CONTROL_AF_TRIGGER_CANCEL); 736 mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, 737 CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH); 738 mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback, 739 mBackgroundHandler); 740 // After this, the camera will go back to the normal state of preview. 741 mState = STATE_PREVIEW; 742 mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback, 743 mBackgroundHandler); 744 } catch (CameraAccessException e) { 745 e.printStackTrace(); 746 } 747 } 748 749 @Override 750 public void onClick(View view) { 751 switch (view.getId()) { 752 case R.id.picture: { 753 takePicture(); 754 break; 755 } 756 case R.id.info: { 757 Activity activity = getActivity(); 758 if (null != activity) { 759 new AlertDialog.Builder(activity) 760 .setMessage(R.string.intro_message) 761 .setPositiveButton(android.R.string.ok, null) 762 .show(); 763 } 764 break; 765 } 766 } 767 } 768 769 /** 770 * Saves a JPEG {@link Image} into the specified {@link File}. 771 */ 772 private static class ImageSaver implements Runnable { 773 774 /** 775 * The JPEG image 776 */ 777 private final Image mImage; 778 /** 779 * The file we save the image into. 780 */ 781 private final File mFile; 782 783 public ImageSaver(Image image, File file) { 784 mImage = image; 785 mFile = file; 786 } 787 788 @Override 789 public void run() { 790 ByteBuffer buffer = mImage.getPlanes()[0].getBuffer(); 791 byte[] bytes = new byte[buffer.remaining()]; 792 buffer.get(bytes); 793 FileOutputStream output = null; 794 try { 795 output = new FileOutputStream(mFile); 796 output.write(bytes); 797 } catch (FileNotFoundException e) { 798 e.printStackTrace(); 799 } catch (IOException e) { 800 e.printStackTrace(); 801 } finally { 802 mImage.close(); 803 if (null != output) { 804 try { 805 output.close(); 806 } catch (IOException e) { 807 e.printStackTrace(); 808 } 809 } 810 } 811 } 812 813 } 814 815 /** 816 * Compares two {@code Size}s based on their areas. 817 */ 818 static class CompareSizesByArea implements Comparator<Size> { 819 820 @Override 821 public int compare(Size lhs, Size rhs) { 822 // We cast here to ensure the multiplications won't overflow 823 return Long.signum((long) lhs.getWidth() * lhs.getHeight() - 824 (long) rhs.getWidth() * rhs.getHeight()); 825 } 826 827 } 828 829 public static class ErrorDialog extends DialogFragment { 830 831 @Override 832 public Dialog onCreateDialog(Bundle savedInstanceState) { 833 final Activity activity = getActivity(); 834 return new AlertDialog.Builder(activity) 835 .setMessage("This device doesn't support Camera2 API.") 836 .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { 837 @Override 838 public void onClick(DialogInterface dialogInterface, int i) { 839 activity.finish(); 840 } 841 }) 842 .create(); 843 } 844 845 } 846 847 } 848