content: /*
   * Copyright (C) 2014 ZXing authors
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.fly.scan.camera;
  
  import android.graphics.Point;
  import android.graphics.Rect;
  import android.hardware.Camera;
  import android.os.Build;
  import android.util.Log;
  
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.List;
  import java.util.regex.Pattern;
  
  /**
   * Utility methods for configuring the Android camera.
   *
   * @author Sean Owen
   */
  @SuppressWarnings("deprecation") // camera APIs
  public final class CameraConfigurationUtils {
  
      private static final String TAG = "CameraConfiguration";
  
      private static final Pattern SEMICOLON = Pattern.compile(";");
  
      private static final int MIN_PREVIEW_PIXELS = 480 * 320; // normal screen
      private static final float MAX_EXPOSURE_COMPENSATION = 1.5f;
      private static final float MIN_EXPOSURE_COMPENSATION = 0.0f;
      private static final double MAX_ASPECT_DISTORTION = 0.15;
      private static final int MIN_FPS = 10;
      private static final int MAX_FPS = 20;
      private static final int AREA_PER_1000 = 400;
  
      private CameraConfigurationUtils() {
      }
  
      public static void setFocus(Camera.Parameters parameters,
                                  boolean autoFocus,
                                  boolean disableContinuous,
                                  boolean safeMode) {
          List<String> supportedFocusModes = parameters.getSupportedFocusModes();
          String focusMode = null;
          if (autoFocus) {
              if (safeMode || disableContinuous) {
                  focusMode = findSettableValue("focus mode",
                          supportedFocusModes,
                          Camera.Parameters.FOCUS_MODE_AUTO);
              } else {
                  focusMode = findSettableValue("focus mode",
                          supportedFocusModes,
                          Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE,
                          Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO,
                          Camera.Parameters.FOCUS_MODE_AUTO);
              }
          }
          // Maybe selected auto-focus but not available, so fall through here:
          if (!safeMode && focusMode == null) {
              focusMode = findSettableValue("focus mode",
                      supportedFocusModes,
                      Camera.Parameters.FOCUS_MODE_MACRO,
                      Camera.Parameters.FOCUS_MODE_EDOF);
          }
          if (focusMode != null) {
              if (focusMode.equals(parameters.getFocusMode())) {
                  Log.i(TAG, "Focus mode already set to " + focusMode);
              } else {
                  parameters.setFocusMode(focusMode);
              }
          }
      }
  
      public static void setTorch(Camera.Parameters parameters, boolean on) {
          List<String> supportedFlashModes = parameters.getSupportedFlashModes();
          String flashMode;
          if (on) {
              flashMode = findSettableValue("flash mode",
                      supportedFlashModes,
                      Camera.Parameters.FLASH_MODE_TORCH,
                      Camera.Parameters.FLASH_MODE_ON);
          } else {
              flashMode = findSettableValue("flash mode",
                      supportedFlashModes,
                      Camera.Parameters.FLASH_MODE_OFF);
          }
          if (flashMode != null) {
              if (flashMode.equals(parameters.getFlashMode())) {
                  Log.i(TAG, "Flash mode already set to " + flashMode);
              } else {
                  Log.i(TAG, "Setting flash mode to " + flashMode);
                  parameters.setFlashMode(flashMode);
              }
          }
      }
  
      public static void setBestExposure(Camera.Parameters parameters, boolean lightOn) {
          int minExposure = parameters.getMinExposureCompensation();
          int maxExposure = parameters.getMaxExposureCompensation();
          float step = parameters.getExposureCompensationStep();
          if ((minExposure != 0 || maxExposure != 0) && step > 0.0f) {
              // Set low when light is on
              float targetCompensation = lightOn ? MIN_EXPOSURE_COMPENSATION : MAX_EXPOSURE_COMPENSATION;
              int compensationSteps = Math.round(targetCompensation / step);
              float actualCompensation = step * compensationSteps;
              // Clamp value:
              compensationSteps = Math.max(Math.min(compensationSteps, maxExposure), minExposure);
              if (parameters.getExposureCompensation() == compensationSteps) {
                  Log.i(TAG, "Exposure compensation already set to " + compensationSteps + " / " + actualCompensation);
              } else {
                  Log.i(TAG, "Setting exposure compensation to " + compensationSteps + " / " + actualCompensation);
                  parameters.setExposureCompensation(compensationSteps);
              }
          } else {
              Log.i(TAG, "Camera does not support exposure compensation");
          }
      }
  
      public static void setBestPreviewFPS(Camera.Parameters parameters) {
          setBestPreviewFPS(parameters, MIN_FPS, MAX_FPS);
      }
  
      public static void setBestPreviewFPS(Camera.Parameters parameters, int minFPS, int maxFPS) {
          List<int[]> supportedPreviewFpsRanges = parameters.getSupportedPreviewFpsRange();
          Log.i(TAG, "Supported FPS ranges: " + toString(supportedPreviewFpsRanges));
          if (supportedPreviewFpsRanges != null && !supportedPreviewFpsRanges.isEmpty()) {
              int[] suitableFPSRange = null;
              for (int[] fpsRange : supportedPreviewFpsRanges) {
                  int thisMin = fpsRange[Camera.Parameters.PREVIEW_FPS_MIN_INDEX];
                  int thisMax = fpsRange[Camera.Parameters.PREVIEW_FPS_MAX_INDEX];
                  if (thisMin >= minFPS * 1000 && thisMax <= maxFPS * 1000) {
                      suitableFPSRange = fpsRange;
                      break;
                  }
              }
              if (suitableFPSRange == null) {
                  Log.i(TAG, "No suitable FPS range?");
              } else {
                  int[] currentFpsRange = new int[2];
                  parameters.getPreviewFpsRange(currentFpsRange);
                  if (Arrays.equals(currentFpsRange, suitableFPSRange)) {
                      Log.i(TAG, "FPS range already set to " + Arrays.toString(suitableFPSRange));
                  } else {
                      Log.i(TAG, "Setting FPS range to " + Arrays.toString(suitableFPSRange));
                      parameters.setPreviewFpsRange(suitableFPSRange[Camera.Parameters.PREVIEW_FPS_MIN_INDEX],
                              suitableFPSRange[Camera.Parameters.PREVIEW_FPS_MAX_INDEX]);
                  }
              }
          }
      }
  
      public static void setFocusArea(Camera.Parameters parameters) {
          if (parameters.getMaxNumFocusAreas() > 0) {
              Log.i(TAG, "Old focus areas: " + toString(parameters.getFocusAreas()));
              List<Camera.Area> middleArea = buildMiddleArea();
              Log.i(TAG, "Setting focus area to : " + toString(middleArea));
              parameters.setFocusAreas(middleArea);
          } else {
              Log.i(TAG, "Device does not support focus areas");
          }
      }
  
      public static void setMetering(Camera.Parameters parameters) {
          if (parameters.getMaxNumMeteringAreas() > 0) {
              Log.i(TAG, "Old metering areas: " + parameters.getMeteringAreas());
              List<Camera.Area> middleArea = buildMiddleArea();
              Log.i(TAG, "Setting metering area to : " + toString(middleArea));
              parameters.setMeteringAreas(middleArea);
          } else {
              Log.i(TAG, "Device does not support metering areas");
          }
      }
  
      private static List<Camera.Area> buildMiddleArea() {
          return Collections.singletonList(
                  new Camera.Area(new Rect(-AREA_PER_1000, -AREA_PER_1000, AREA_PER_1000, AREA_PER_1000), 1));
      }
  
      public static void setVideoStabilization(Camera.Parameters parameters) {
          if (parameters.isVideoStabilizationSupported()) {
              if (parameters.getVideoStabilization()) {
                  Log.i(TAG, "Video stabilization already enabled");
              } else {
                  Log.i(TAG, "Enabling video stabilization...");
                  parameters.setVideoStabilization(true);
              }
          } else {
              Log.i(TAG, "This device does not support video stabilization");
          }
      }
  
      public static void setBarcodeSceneMode(Camera.Parameters parameters) {
          if (Camera.Parameters.SCENE_MODE_BARCODE.equals(parameters.getSceneMode())) {
              Log.i(TAG, "Barcode scene mode already set");
              return;
          }
          String sceneMode = findSettableValue("scene mode",
                  parameters.getSupportedSceneModes(),
                  Camera.Parameters.SCENE_MODE_BARCODE);
          if (sceneMode != null) {
              parameters.setSceneMode(sceneMode);
          }
      }
  
      public static void setZoom(Camera.Parameters parameters, double targetZoomRatio) {
          if (parameters.isZoomSupported()) {
              Integer zoom = indexOfClosestZoom(parameters, targetZoomRatio);
              if (zoom == null) {
                  return;
              }
              if (parameters.getZoom() == zoom) {
                  Log.i(TAG, "Zoom is already set to " + zoom);
              } else {
                  Log.i(TAG, "Setting zoom to " + zoom);
                  parameters.setZoom(zoom);
              }
          } else {
              Log.i(TAG, "Zoom is not supported");
          }
      }
  
      private static Integer indexOfClosestZoom(Camera.Parameters parameters, double targetZoomRatio) {
          List<Integer> ratios = parameters.getZoomRatios();
          Log.i(TAG, "Zoom ratios: " + ratios);
          int maxZoom = parameters.getMaxZoom();
          if (ratios == null || ratios.isEmpty() || ratios.size() != maxZoom + 1) {
              Log.w(TAG, "Invalid zoom ratios!");
              return null;
          }
          double target100 = 100.0 * targetZoomRatio;
          double smallestDiff = Double.POSITIVE_INFINITY;
          int closestIndex = 0;
          for (int i = 0; i < ratios.size(); i++) {
              double diff = Math.abs(ratios.get(i) - target100);
              if (diff < smallestDiff) {
                  smallestDiff = diff;
                  closestIndex = i;
              }
          }
          Log.i(TAG, "Chose zoom ratio of " + (ratios.get(closestIndex) / 100.0));
          return closestIndex;
      }
  
      public static void setInvertColor(Camera.Parameters parameters) {
          if (Camera.Parameters.EFFECT_NEGATIVE.equals(parameters.getColorEffect())) {
              Log.i(TAG, "Negative effect already set");
              return;
          }
          String colorMode = findSettableValue("color effect",
                  parameters.getSupportedColorEffects(),
                  Camera.Parameters.EFFECT_NEGATIVE);
          if (colorMode != null) {
              parameters.setColorEffect(colorMode);
          }
      }
  
      public static Point findBestPreviewSizeValue(Camera.Parameters parameters, Point screenResolution) {
  
          List<Camera.Size> rawSupportedSizes = parameters.getSupportedPreviewSizes();
          if (rawSupportedSizes == null) {
              Log.w(TAG, "Device returned no supported preview sizes; using default");
              Camera.Size defaultSize = parameters.getPreviewSize();
              if (defaultSize == null) {
                  throw new IllegalStateException("Parameters contained no preview size!");
              }
              return new Point(defaultSize.width, defaultSize.height);
          }
  
          if (Log.isLoggable(TAG, Log.INFO)) {
              StringBuilder previewSizesString = new StringBuilder();
              for (Camera.Size size : rawSupportedSizes) {
                  previewSizesString.append(size.width).append('x').append(size.height).append(' ');
              }
              Log.i(TAG, "Supported preview sizes: " + previewSizesString);
          }
  
          double screenAspectRatio = screenResolution.x / (double) screenResolution.y;
  
          // Find a suitable size, with max resolution
          int maxResolution = 0;
          Camera.Size maxResPreviewSize = null;
          for (Camera.Size size : rawSupportedSizes) {
              int realWidth = size.width;
              int realHeight = size.height;
              int resolution = realWidth * realHeight;
              if (resolution < MIN_PREVIEW_PIXELS) {
                  continue;
              }
  
              boolean isCandidatePortrait = realWidth < realHeight;
              int maybeFlippedWidth = isCandidatePortrait ? realHeight : realWidth;
              int maybeFlippedHeight = isCandidatePortrait ? realWidth : realHeight;
              double aspectRatio = maybeFlippedWidth / (double) maybeFlippedHeight;
              double distortion = Math.abs(aspectRatio - screenAspectRatio);
              if (distortion > MAX_ASPECT_DISTORTION) {
                  continue;
              }
  
              if (maybeFlippedWidth == screenResolution.x && maybeFlippedHeight == screenResolution.y) {
                  Point exactPoint = new Point(realWidth, realHeight);
                  Log.i(TAG, "Found preview size exactly matching screen size: " + exactPoint);
                  return exactPoint;
              }
  
              // Resolution is suitable; record the one with max resolution
              if (resolution > maxResolution) {
                  maxResolution = resolution;
                  maxResPreviewSize = size;
              }
          }
  
          // If no exact match, use largest preview size. This was not a great idea on older devices because
          // of the additional computation needed. We're likely to get here on newer Android 4+ devices, where
          // the CPU is much more powerful.
          if (maxResPreviewSize != null) {
              Point largestSize = new Point(maxResPreviewSize.width, maxResPreviewSize.height);
              Log.i(TAG, "Using largest suitable preview size: " + largestSize);
              return largestSize;
          }
  
          // If there is nothing at all suitable, return current preview size
          Camera.Size defaultPreview = parameters.getPreviewSize();
          if (defaultPreview == null) {
              throw new IllegalStateException("Parameters contained no preview size!");
          }
          Point defaultSize = new Point(defaultPreview.width, defaultPreview.height);
          Log.i(TAG, "No suitable preview sizes, using default: " + defaultSize);
          return defaultSize;
      }
  
      private static String findSettableValue(String name,
                                              Collection<String> supportedValues,
                                              String... desiredValues) {
          Log.i(TAG, "Requesting " + name + " value from among: " + Arrays.toString(desiredValues));
          Log.i(TAG, "Supported " + name + " values: " + supportedValues);
          if (supportedValues != null) {
              for (String desiredValue : desiredValues) {
                  if (supportedValues.contains(desiredValue)) {
                      Log.i(TAG, "Can set " + name + " to: " + desiredValue);
                      return desiredValue;
                  }
              }
          }
          Log.i(TAG, "No supported values match");
          return null;
      }
  
      private static String toString(Collection<int[]> arrays) {
          if (arrays == null || arrays.isEmpty()) {
              return "[]";
          }
          StringBuilder buffer = new StringBuilder();
          buffer.append('[');
          Iterator<int[]> it = arrays.iterator();
          while (it.hasNext()) {
              buffer.append(Arrays.toString(it.next()));
              if (it.hasNext()) {
                  buffer.append(", ");
              }
          }
          buffer.append(']');
          return buffer.toString();
      }
  
      private static String toString(Iterable<Camera.Area> areas) {
          if (areas == null) {
              return null;
          }
          StringBuilder result = new StringBuilder();
          for (Camera.Area area : areas) {
              result.append(area.rect).append(':').append(area.weight).append(' ');
          }
          return result.toString();
      }
  
      public static String collectStats(Camera.Parameters parameters) {
          return collectStats(parameters.flatten());
      }
  
      public static String collectStats(CharSequence flattenedParams) {
          StringBuilder result = new StringBuilder(1000);
          appendStat(result, "BOARD", Build.BOARD);
          appendStat(result, "BRAND", Build.BRAND);
          appendStat(result, "CPU_ABI", Build.CPU_ABI);
          appendStat(result, "DEVICE", Build.DEVICE);
          appendStat(result, "DISPLAY", Build.DISPLAY);
          appendStat(result, "FINGERPRINT", Build.FINGERPRINT);
          appendStat(result, "HOST", Build.HOST);
          appendStat(result, "ID", Build.ID);
          appendStat(result, "MANUFACTURER", Build.MANUFACTURER);
          appendStat(result, "MODEL", Build.MODEL);
          appendStat(result, "PRODUCT", Build.PRODUCT);
          appendStat(result, "TAGS", Build.TAGS);
          appendStat(result, "TIME", Build.TIME);
          appendStat(result, "TYPE", Build.TYPE);
          appendStat(result, "USER", Build.USER);
          appendStat(result, "VERSION.CODENAME", Build.VERSION.CODENAME);
          appendStat(result, "VERSION.INCREMENTAL", Build.VERSION.INCREMENTAL);
          appendStat(result, "VERSION.RELEASE", Build.VERSION.RELEASE);
          appendStat(result, "VERSION.SDK_INT", Build.VERSION.SDK_INT);
  
          if (flattenedParams != null) {
              String[] params = SEMICOLON.split(flattenedParams);
              Arrays.sort(params);
              for (String param : params) {
                  result.append(param).append('\n');
              }
          }
  
          return result.toString();
      }
  
      private static void appendStat(StringBuilder builder, String stat, Object value) {
          builder.append(stat).append('=').append(value).append('\n');
      }
  
  }
  