content: /*
   * Copyright 2002-2019 Drew Noakes and contributors
   *
   *    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
   *
   *        https://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.
   *
   * More information about this project is available at:
   *
   *    https://drewnoakes.com/code/exif/
   *    https://github.com/drewnoakes/metadata-extractor
   */
  package com.drew.metadata.exif.makernotes;
  
  import com.drew.lang.annotations.NotNull;
  import com.drew.lang.annotations.Nullable;
  import com.drew.metadata.TagDescriptor;
  
  import java.text.DecimalFormat;
  import java.util.HashMap;
  
  import static com.drew.metadata.exif.makernotes.CanonMakernoteDirectory.*;
  
  /**
   * Provides human-readable string representations of tag values stored in a {@link CanonMakernoteDirectory}.
   *
   * @author Drew Noakes https://drewnoakes.com
   */
  @SuppressWarnings("WeakerAccess")
  public class CanonMakernoteDescriptor extends TagDescriptor<CanonMakernoteDirectory>
  {
      public CanonMakernoteDescriptor(@NotNull CanonMakernoteDirectory directory)
      {
          super(directory);
      }
  
      @Override
      @Nullable
      public String getDescription(int tagType)
      {
          switch (tagType) {
              case TAG_CANON_SERIAL_NUMBER:
                  return getSerialNumberDescription();
              case CameraSettings.TAG_FLASH_ACTIVITY:
                  return getFlashActivityDescription();
              case CameraSettings.TAG_FOCUS_TYPE:
                  return getFocusTypeDescription();
              case CameraSettings.TAG_DIGITAL_ZOOM:
                  return getDigitalZoomDescription();
              case CameraSettings.TAG_RECORD_MODE:
                  return getRecordModeDescription();
              case CameraSettings.TAG_QUALITY:
                  return getQualityDescription();
              case CameraSettings.TAG_MACRO_MODE:
                  return getMacroModeDescription();
              case CameraSettings.TAG_SELF_TIMER_DELAY:
                  return getSelfTimerDelayDescription();
              case CameraSettings.TAG_FLASH_MODE:
                  return getFlashModeDescription();
              case CameraSettings.TAG_CONTINUOUS_DRIVE_MODE:
                  return getContinuousDriveModeDescription();
              case CameraSettings.TAG_FOCUS_MODE_1:
                  return getFocusMode1Description();
              case CameraSettings.TAG_IMAGE_SIZE:
                  return getImageSizeDescription();
              case CameraSettings.TAG_EASY_SHOOTING_MODE:
                  return getEasyShootingModeDescription();
              case CameraSettings.TAG_CONTRAST:
                  return getContrastDescription();
              case CameraSettings.TAG_SATURATION:
                  return getSaturationDescription();
              case CameraSettings.TAG_SHARPNESS:
                  return getSharpnessDescription();
              case CameraSettings.TAG_ISO:
                  return getIsoDescription();
              case CameraSettings.TAG_METERING_MODE:
                  return getMeteringModeDescription();
              case CameraSettings.TAG_AF_POINT_SELECTED:
                  return getAfPointSelectedDescription();
              case CameraSettings.TAG_EXPOSURE_MODE:
                  return getExposureModeDescription();
              case CameraSettings.TAG_LENS_TYPE:
                  return getLensTypeDescription();
              case CameraSettings.TAG_LONG_FOCAL_LENGTH:
                  return getLongFocalLengthDescription();
              case CameraSettings.TAG_SHORT_FOCAL_LENGTH:
                  return getShortFocalLengthDescription();
              case CameraSettings.TAG_FOCAL_UNITS_PER_MM:
                  return getFocalUnitsPerMillimetreDescription();
              case CameraSettings.TAG_FLASH_DETAILS:
                  return getFlashDetailsDescription();
              case CameraSettings.TAG_FOCUS_MODE_2:
                  return getFocusMode2Description();
              case FocalLength.TAG_WHITE_BALANCE:
                  return getWhiteBalanceDescription();
              case FocalLength.TAG_AF_POINT_USED:
                  return getAfPointUsedDescription();
              case FocalLength.TAG_FLASH_BIAS:
                  return getFlashBiasDescription();
              case AFInfo.TAG_AF_POINTS_IN_FOCUS:
                  return getTagAfPointsInFocus();
              case CameraSettings.TAG_MAX_APERTURE:
                  return getMaxApertureDescription();
              case CameraSettings.TAG_MIN_APERTURE:
                  return getMinApertureDescription();
              case CameraSettings.TAG_FOCUS_CONTINUOUS:
                  return getFocusContinuousDescription();
              case CameraSettings.TAG_AE_SETTING:
                  return getAESettingDescription();
              case CanonMakernoteDirectory.CameraSettings.TAG_DISPLAY_APERTURE:
                  return getDisplayApertureDescription();
              case CanonMakernoteDirectory.CameraSettings.TAG_SPOT_METERING_MODE:
                  return getSpotMeteringModeDescription();
              case CanonMakernoteDirectory.CameraSettings.TAG_PHOTO_EFFECT:
                  return getPhotoEffectDescription();
              case CanonMakernoteDirectory.CameraSettings.TAG_MANUAL_FLASH_OUTPUT:
                  return getManualFlashOutputDescription();
              case CanonMakernoteDirectory.CameraSettings.TAG_COLOR_TONE:
                  return getColorToneDescription();
              case CanonMakernoteDirectory.CameraSettings.TAG_SRAW_QUALITY:
                  return getSRawQualityDescription();
  
              // It turns out that these values are dependent upon the camera model and therefore the below code was
              // incorrect for some Canon models.  This needs to be revisited.
  
  //            case TAG_CANON_CUSTOM_FUNCTION_LONG_EXPOSURE_NOISE_REDUCTION:
  //                return getLongExposureNoiseReductionDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_SHUTTER_AUTO_EXPOSURE_LOCK_BUTTONS:
  //                return getShutterAutoExposureLockButtonDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_MIRROR_LOCKUP:
  //                return getMirrorLockupDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_TV_AV_AND_EXPOSURE_LEVEL:
  //                return getTvAndAvExposureLevelDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_AF_ASSIST_LIGHT:
  //                return getAutoFocusAssistLightDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_SHUTTER_SPEED_IN_AV_MODE:
  //                return getShutterSpeedInAvModeDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_BRACKETING:
  //                return getAutoExposureBracketingSequenceAndAutoCancellationDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_SHUTTER_CURTAIN_SYNC:
  //                return getShutterCurtainSyncDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_AF_STOP:
  //                return getLensAutoFocusStopButtonDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_FILL_FLASH_REDUCTION:
  //                return getFillFlashReductionDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_MENU_BUTTON_RETURN:
  //                return getMenuButtonReturnPositionDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_SET_BUTTON_FUNCTION:
  //                return getSetButtonFunctionWhenShootingDescription();
  //            case TAG_CANON_CUSTOM_FUNCTION_SENSOR_CLEANING:
  //                return getSensorCleaningDescription();
              default:
                  return super.getDescription(tagType);
          }
      }
  
      @Nullable
      public String getSerialNumberDescription()
      {
          // https://www.ozhiker.com/electronics/pjmt/jpeg_info/canon_mn.html
          Integer value = _directory.getInteger(TAG_CANON_SERIAL_NUMBER);
          if (value == null)
              return null;
          return String.format("%04X%05d", (value >> 8) & 0xFF, value & 0xFF);
      }
  
  /*
      @Nullable
      public String getLongExposureNoiseReductionDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_LONG_EXPOSURE_NOISE_REDUCTION);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "Off";
              case 1:     return "On";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getShutterAutoExposureLockButtonDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_SHUTTER_AUTO_EXPOSURE_LOCK_BUTTONS);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "AF/AE lock";
              case 1:     return "AE lock/AF";
              case 2:     return "AF/AF lock";
              case 3:     return "AE+release/AE+AF";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getMirrorLockupDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_MIRROR_LOCKUP);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "Disabled";
              case 1:     return "Enabled";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getTvAndAvExposureLevelDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_TV_AV_AND_EXPOSURE_LEVEL);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "1/2 stop";
              case 1:     return "1/3 stop";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getAutoFocusAssistLightDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_AF_ASSIST_LIGHT);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "On (Auto)";
              case 1:     return "Off";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getShutterSpeedInAvModeDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_SHUTTER_SPEED_IN_AV_MODE);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "Automatic";
              case 1:     return "1/200 (fixed)";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getAutoExposureBracketingSequenceAndAutoCancellationDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_BRACKETING);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "0,-,+ / Enabled";
              case 1:     return "0,-,+ / Disabled";
              case 2:     return "-,0,+ / Enabled";
              case 3:     return "-,0,+ / Disabled";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getShutterCurtainSyncDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_SHUTTER_CURTAIN_SYNC);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "1st Curtain Sync";
              case 1:     return "2nd Curtain Sync";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getLensAutoFocusStopButtonDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_AF_STOP);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "AF stop";
              case 1:     return "Operate AF";
              case 2:     return "Lock AE and start timer";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getFillFlashReductionDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_FILL_FLASH_REDUCTION);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "Enabled";
              case 1:     return "Disabled";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getMenuButtonReturnPositionDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_MENU_BUTTON_RETURN);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "Top";
              case 1:     return "Previous (volatile)";
              case 2:     return "Previous";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getSetButtonFunctionWhenShootingDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_SET_BUTTON_FUNCTION);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "Not Assigned";
              case 1:     return "Change Quality";
              case 2:     return "Change ISO Speed";
              case 3:     return "Select Parameters";
              default:    return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getSensorCleaningDescription()
      {
          Integer value = _directory.getInteger(TAG_CANON_CUSTOM_FUNCTION_SENSOR_CLEANING);
          if (value==null)
              return null;
          switch (value) {
              case 0:     return "Disabled";
              case 1:     return "Enabled";
              default:    return "Unknown (" + value + ")";
          }
      }
  */
  
      @Nullable
      public String getFlashBiasDescription()
      {
          Integer value = _directory.getInteger(FocalLength.TAG_FLASH_BIAS);
  
          if (value == null)
              return null;
  
          boolean isNegative = false;
          if (value > 0xF000) {
              isNegative = true;
              value = 0xFFFF - value;
              value++;
          }
  
          // this tag is interesting in that the values returned are:
          //  0, 0.375, 0.5, 0.626, 1
          // not
          //  0, 0.33,  0.5, 0.66,  1
  
          return (isNegative ? "-" : "") + Float.toString(value / 32f) + " EV";
      }
  
      @Nullable
      public String getAfPointUsedDescription()
      {
          Integer value = _directory.getInteger(FocalLength.TAG_AF_POINT_USED);
          if (value == null)
              return null;
          if ((value & 0x7) == 0) {
              return "Right";
          } else if ((value & 0x7) == 1) {
              return "Centre";
          } else if ((value & 0x7) == 2) {
              return "Left";
          } else {
              return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getTagAfPointsInFocus()
      {
          Integer value = _directory.getInteger(AFInfo.TAG_AF_POINTS_IN_FOCUS);
          if (value == null)
              return null;
  
          StringBuilder sb = new StringBuilder();
  
          for (int i = 0; i < 16; i++)
          {
              if ((value & 1 << i) != 0)
              {
                  if (sb.length() != 0)
                      sb.append(',');
                  sb.append(i);
              }
          }
  
          return sb.length() == 0 ? "None" : sb.toString();
      }
  
      @Nullable
      public String getWhiteBalanceDescription()
      {
          return getIndexedDescription(
              FocalLength.TAG_WHITE_BALANCE,
              "Auto",
              "Sunny",
              "Cloudy",
              "Tungsten",
              "Florescent",
              "Flash",
              "Custom"
          );
      }
  
      @Nullable
      public String getFocusMode2Description()
      {
          return getIndexedDescription(CameraSettings.TAG_FOCUS_MODE_2, "Single", "Continuous");
      }
  
      @Nullable
      public String getFlashDetailsDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_FLASH_DETAILS);
          if (value == null)
              return null;
          if (((value >> 14) & 1) != 0) {
              return "External E-TTL";
          }
          if (((value >> 13) & 1) != 0) {
              return "Internal flash";
          }
          if (((value >> 11) & 1) != 0) {
              return "FP sync used";
          }
          if (((value >> 4) & 1) != 0) {
              return "FP sync enabled";
          }
          return "Unknown (" + value + ")";
      }
  
      @Nullable
      public String getFocalUnitsPerMillimetreDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_FOCAL_UNITS_PER_MM);
          if (value == null)
              return null;
          if (value != 0) {
              return Integer.toString(value);
          } else {
              return "";
          }
      }
  
      @Nullable
      public String getShortFocalLengthDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_SHORT_FOCAL_LENGTH);
          if (value == null)
              return null;
          String units = getFocalUnitsPerMillimetreDescription();
          return Integer.toString(value) + " " + units;
      }
  
      @Nullable
      public String getLongFocalLengthDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_LONG_FOCAL_LENGTH);
          if (value == null)
              return null;
          String units = getFocalUnitsPerMillimetreDescription();
          return Integer.toString(value) + " " + units;
      }
  
      @Nullable
      public String getExposureModeDescription()
      {
          return getIndexedDescription(
              CameraSettings.TAG_EXPOSURE_MODE,
              "Easy shooting",
              "Program",
              "Tv-priority",
              "Av-priority",
              "Manual",
              "A-DEP"
          );
      }
  
      @Nullable
      public String getLensTypeDescription() {
          Integer value = _directory.getInteger(CameraSettings.TAG_LENS_TYPE);
          if (value == null)
              return null;
  
          return _lensTypeById.containsKey(value)
              ? _lensTypeById.get(value)
              : String.format("Unknown (%d)", value);
      }
  
      @Nullable
      public String getMaxApertureDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_MAX_APERTURE);
          if (value == null)
              return null;
          if (value > 512)
              return String.format("Unknown (%d)", value);
          return getFStopDescription(Math.exp(decodeCanonEv(value) * Math.log(2.0) / 2.0));
      }
  
      @Nullable
      public String getMinApertureDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_MIN_APERTURE);
          if (value == null)
              return null;
          if (value > 512)
              return String.format("Unknown (%d)", value);
          return getFStopDescription(Math.exp(decodeCanonEv(value) * Math.log(2.0) / 2.0));
      }
  
      @Nullable
      public String getAfPointSelectedDescription()
      {
          return getIndexedDescription(
              CameraSettings.TAG_AF_POINT_SELECTED,
              0x3000,
              "None (MF)",
              "Auto selected",
              "Right",
              "Centre",
              "Left"
          );
      }
  
      @Nullable
      public String getMeteringModeDescription()
      {
          return getIndexedDescription(
              CameraSettings.TAG_METERING_MODE,
              3,
              "Evaluative",
              "Partial",
              "Centre weighted"
          );
      }
  
      @Nullable
      public String getIsoDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_ISO);
          if (value == null)
              return null;
  
          // Canon PowerShot S3 is special
          int canonMask = 0x4000;
          if ((value & canonMask) != 0)
              return "" + (value & ~canonMask);
  
          switch (value) {
              case 0:
                  return "Not specified (see ISOSpeedRatings tag)";
              case 15:
                  return "Auto";
              case 16:
                  return "50";
              case 17:
                  return "100";
              case 18:
                  return "200";
              case 19:
                  return "400";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getSharpnessDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_SHARPNESS);
          if (value == null)
              return null;
          switch (value) {
              case 0xFFFF:
                  return "Low";
              case 0x000:
                  return "Normal";
              case 0x001:
                  return "High";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getSaturationDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_SATURATION);
          if (value == null)
              return null;
          switch (value) {
              case 0xFFFF:
                  return "Low";
              case 0x000:
                  return "Normal";
              case 0x001:
                  return "High";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getContrastDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_CONTRAST);
          if (value == null)
              return null;
          switch (value) {
              case 0xFFFF:
                  return "Low";
              case 0x000:
                  return "Normal";
              case 0x001:
                  return "High";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getEasyShootingModeDescription()
      {
          return getIndexedDescription(
              CameraSettings.TAG_EASY_SHOOTING_MODE,
              "Full auto",
              "Manual",
              "Landscape",
              "Fast shutter",
              "Slow shutter",
              "Night",
              "B&W",
              "Sepia",
              "Portrait",
              "Sports",
              "Macro / Closeup",
              "Pan focus"
          );
      }
  
      @Nullable
      public String getImageSizeDescription()
      {
          return getIndexedDescription(
              CameraSettings.TAG_IMAGE_SIZE,
              "Large",
              "Medium",
              "Small"
          );
      }
  
      @Nullable
      public String getFocusMode1Description()
      {
          return getIndexedDescription(
              CameraSettings.TAG_FOCUS_MODE_1,
              "One-shot",
              "AI Servo",
              "AI Focus",
              "Manual Focus",
              // TODO should check field 32 here (FOCUS_MODE_2)
              "Single",
              "Continuous",
              "Manual Focus"
          );
      }
  
      @Nullable
      public String getContinuousDriveModeDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_CONTINUOUS_DRIVE_MODE);
          if (value == null)
              return null;
          switch (value) {
              case 0:
                  final Integer delay = _directory.getInteger(CameraSettings.TAG_SELF_TIMER_DELAY);
                  if (delay != null)
                      return delay == 0 ? "Single shot" : "Single shot with self-timer";
              case 1:
                  return "Continuous";
          }
          return "Unknown (" + value + ")";
      }
  
      @Nullable
      public String getFlashModeDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_FLASH_MODE);
          if (value == null)
              return null;
          switch (value) {
              case 0:
                  return "No flash fired";
              case 1:
                  return "Auto";
              case 2:
                  return "On";
              case 3:
                  return "Red-eye reduction";
              case 4:
                  return "Slow-synchro";
              case 5:
                  return "Auto and red-eye reduction";
              case 6:
                  return "On and red-eye reduction";
              case 16:
                  // note: this value not set on Canon D30
                  return "External flash";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getSelfTimerDelayDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_SELF_TIMER_DELAY);
          if (value == null)
              return null;
          if (value == 0) {
              return "Self timer not used";
          } else {
              DecimalFormat format = new DecimalFormat("0.##");
              return format.format((double)value * 0.1d) + " sec";
          }
      }
  
      @Nullable
      public String getMacroModeDescription()
      {
          return getIndexedDescription(CameraSettings.TAG_MACRO_MODE, 1, "Macro", "Normal");
      }
  
      @Nullable
      public String getQualityDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_QUALITY);
          if (value == null)
              return null;
          switch (value) {
              case -1:
                  return "n/a";
              case 1:
                  return "Economy";
              case 2:
                  return "Normal";
              case 3:
                  return "Fine";
              case 4:
                  return "RAW";
              case 5:
                  return "Superfine";
              case 7:
                  return "CRAW";
              case 130:
                  return "Normal Movie";
              case 1131:
                  return "Movie (2)";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getDigitalZoomDescription()
      {
          return getIndexedDescription(CameraSettings.TAG_DIGITAL_ZOOM, "No digital zoom", "2x", "4x");
      }
  
      @Nullable
      public String getRecordModeDescription()
      {
          return getIndexedDescription(CameraSettings.TAG_RECORD_MODE, 1, "JPEG", "CRW+THM", "AVI+THM", "TIF", "TIF+JPEG", "CR2", "CR2+JPEG", null, "MOV", "MP4");
      }
  
      @Nullable
      public String getFocusTypeDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_FOCUS_TYPE);
          if (value == null)
              return null;
          switch (value) {
              case 0:
                  return "Manual";
              case 1:
                  return "Auto";
              case 3:
                  return "Close-up (Macro)";
              case 8:
                  return "Locked (Pan Mode)";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getFlashActivityDescription()
      {
          return getIndexedDescription(CameraSettings.TAG_FLASH_ACTIVITY, "Flash did not fire", "Flash fired");
      }
  
      @Nullable
      public String getFocusContinuousDescription()
      {
          return getIndexedDescription(CameraSettings.TAG_FOCUS_CONTINUOUS, 0,
              "Single", "Continuous", null, null, null, null, null, null, "Manual");
      }
  
      @Nullable
      public String getAESettingDescription()
      {
          return getIndexedDescription(CameraSettings.TAG_AE_SETTING, 0,
              "Normal AE", "Exposure Compensation", "AE Lock", "AE Lock + Exposure Comp.", "No AE");
      }
  
      @Nullable
      public String getDisplayApertureDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_DISPLAY_APERTURE);
          if (value == null)
              return null;
  
          if (value == 0xFFFF)
              return value.toString();
          return getFStopDescription(value / 10f);
      }
  
      @Nullable
      public String getSpotMeteringModeDescription()
      {
          return getIndexedDescription(CanonMakernoteDirectory.CameraSettings.TAG_SPOT_METERING_MODE, 0,
              "Center", "AF Point");
      }
  
      @Nullable
      public String getPhotoEffectDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_PHOTO_EFFECT);
          if (value == null)
              return null;
  
          switch (value)
          {
              case 0:
                  return "Off";
              case 1:
                  return "Vivid";
              case 2:
                  return "Neutral";
              case 3:
                  return "Smooth";
              case 4:
                  return "Sepia";
              case 5:
                  return "B&W";
              case 6:
                  return "Custom";
              case 100:
                  return "My Color Data";
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getManualFlashOutputDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_MANUAL_FLASH_OUTPUT);
          if (value == null)
              return null;
  
          switch (value)
          {
              case 0:
                  return "n/a";
              case 0x500:
                  return "Full";
              case 0x502:
                  return "Medium";
              case 0x504:
                  return "Low";
              case 0x7fff:
                  return "n/a";   // (EOS models)
              default:
                  return "Unknown (" + value + ")";
          }
      }
  
      @Nullable
      public String getColorToneDescription()
      {
          Integer value = _directory.getInteger(CameraSettings.TAG_COLOR_TONE);
          if (value == null)
              return null;
  
          return value == 0x7fff ? "n/a" : value.toString();
      }
  
      @Nullable
      public String getSRawQualityDescription()
      {
          return getIndexedDescription(CanonMakernoteDirectory.CameraSettings.TAG_SRAW_QUALITY, 0, "n/a", "sRAW1 (mRAW)", "sRAW2 (sRAW)");
      }
  
      /**
       * Canon hex-based EV (modulo 0x20) to real number.
       *
       * Converted from Exiftool version 10.10 created by Phil Harvey
       * https://www.sno.phy.queensu.ca/~phil/exiftool/
       * lib\Image\ExifTool\Canon.pm
       *
       *         eg) 0x00 -> 0
       *             0x0c -> 0.33333
       *             0x10 -> 0.5
       *             0x14 -> 0.66666
       *             0x20 -> 1   ... etc
       */
      private double decodeCanonEv(int val)
      {
          int sign = 1;
          if (val < 0)
          {
              val = -val;
              sign = -1;
          }
  
          int frac = val & 0x1f;
          val -= frac;
  
          if (frac == 0x0c)
              frac = 0x20 / 3;
          else if (frac == 0x14)
              frac = 0x40 / 3;
  
          return sign * (val + frac) / (double)0x20;
      }
  
      /**
       *  Map from <see cref="CanonMakernoteDirectory.CameraSettings.TagLensType"/> to string descriptions.
       *
       *  Data sourced from https://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/Canon.html#LensType
       *
       *  Note that only Canon lenses are listed. Lenses from other manufacturers may identify themselves to the camera
       *  as being from this set, but in fact may be quite different. This limits the usefulness of this data,
       *  unfortunately.
       */
      private static final HashMap<Integer, String> _lensTypeById = new HashMap<Integer, String>();
  
      static {
          _lensTypeById.put(1, "Canon EF 50mm f/1.8");
          _lensTypeById.put(2, "Canon EF 28mm f/2.8");
          _lensTypeById.put(3, "Canon EF 135mm f/2.8 Soft");
          _lensTypeById.put(4, "Canon EF 35-105mm f/3.5-4.5 or Sigma Lens");
          _lensTypeById.put(5, "Canon EF 35-70mm f/3.5-4.5");
          _lensTypeById.put(6, "Canon EF 28-70mm f/3.5-4.5 or Sigma or Tokina Lens");
          _lensTypeById.put(7, "Canon EF 100-300mm f/5.6L");
          _lensTypeById.put(8, "Canon EF 100-300mm f/5.6 or Sigma or Tokina Lens");
          _lensTypeById.put(9, "Canon EF 70-210mm f/4");
          _lensTypeById.put(10, "Canon EF 50mm f/2.5 Macro or Sigma Lens");
          _lensTypeById.put(11, "Canon EF 35mm f/2");
          _lensTypeById.put(13, "Canon EF 15mm f/2.8 Fisheye");
          _lensTypeById.put(14, "Canon EF 50-200mm f/3.5-4.5L");
          _lensTypeById.put(15, "Canon EF 50-200mm f/3.5-4.5");
          _lensTypeById.put(16, "Canon EF 35-135mm f/3.5-4.5");
          _lensTypeById.put(17, "Canon EF 35-70mm f/3.5-4.5A");
          _lensTypeById.put(18, "Canon EF 28-70mm f/3.5-4.5");
          _lensTypeById.put(20, "Canon EF 100-200mm f/4.5A");
          _lensTypeById.put(21, "Canon EF 80-200mm f/2.8L");
          _lensTypeById.put(22, "Canon EF 20-35mm f/2.8L or Tokina Lens");
          _lensTypeById.put(23, "Canon EF 35-105mm f/3.5-4.5");
          _lensTypeById.put(24, "Canon EF 35-80mm f/4-5.6 Power Zoom");
          _lensTypeById.put(25, "Canon EF 35-80mm f/4-5.6 Power Zoom");
          _lensTypeById.put(26, "Canon EF 100mm f/2.8 Macro or Other Lens");
          _lensTypeById.put(27, "Canon EF 35-80mm f/4-5.6");
          _lensTypeById.put(28, "Canon EF 80-200mm f/4.5-5.6 or Tamron Lens");
          _lensTypeById.put(29, "Canon EF 50mm f/1.8 II");
          _lensTypeById.put(30, "Canon EF 35-105mm f/4.5-5.6");
          _lensTypeById.put(31, "Canon EF 75-300mm f/4-5.6 or Tamron Lens");
          _lensTypeById.put(32, "Canon EF 24mm f/2.8 or Sigma Lens");
          _lensTypeById.put(33, "Voigtlander or Carl Zeiss Lens");
          _lensTypeById.put(35, "Canon EF 35-80mm f/4-5.6");
          _lensTypeById.put(36, "Canon EF 38-76mm f/4.5-5.6");
          _lensTypeById.put(37, "Canon EF 35-80mm f/4-5.6 or Tamron Lens");
          _lensTypeById.put(38, "Canon EF 80-200mm f/4.5-5.6");
          _lensTypeById.put(39, "Canon EF 75-300mm f/4-5.6");
          _lensTypeById.put(40, "Canon EF 28-80mm f/3.5-5.6");
          _lensTypeById.put(41, "Canon EF 28-90mm f/4-5.6");
          _lensTypeById.put(42, "Canon EF 28-200mm f/3.5-5.6 or Tamron Lens");
          _lensTypeById.put(43, "Canon EF 28-105mm f/4-5.6");
          _lensTypeById.put(44, "Canon EF 90-300mm f/4.5-5.6");
          _lensTypeById.put(45, "Canon EF-S 18-55mm f/3.5-5.6 [II]");
          _lensTypeById.put(46, "Canon EF 28-90mm f/4-5.6");
          _lensTypeById.put(47, "Zeiss Milvus 35mm f/2 or 50mm f/2");
          _lensTypeById.put(48, "Canon EF-S 18-55mm f/3.5-5.6 IS");
          _lensTypeById.put(49, "Canon EF-S 55-250mm f/4-5.6 IS");
          _lensTypeById.put(50, "Canon EF-S 18-200mm f/3.5-5.6 IS");
          _lensTypeById.put(51, "Canon EF-S 18-135mm f/3.5-5.6 IS");
          _lensTypeById.put(52, "Canon EF-S 18-55mm f/3.5-5.6 IS II");
          _lensTypeById.put(53, "Canon EF-S 18-55mm f/3.5-5.6 III");
          _lensTypeById.put(54, "Canon EF-S 55-250mm f/4-5.6 IS II");
          _lensTypeById.put(94, "Canon TS-E 17mm f/4L");
          _lensTypeById.put(95, "Canon TS-E 24.0mm f/3.5 L II");
          _lensTypeById.put(124, "Canon MP-E 65mm f/2.8 1-5x Macro Photo");
          _lensTypeById.put(125, "Canon TS-E 24mm f/3.5L");
          _lensTypeById.put(126, "Canon TS-E 45mm f/2.8");
          _lensTypeById.put(127, "Canon TS-E 90mm f/2.8");
          _lensTypeById.put(129, "Canon EF 300mm f/2.8L");
          _lensTypeById.put(130, "Canon EF 50mm f/1.0L");
          _lensTypeById.put(131, "Canon EF 28-80mm f/2.8-4L or Sigma Lens");
          _lensTypeById.put(132, "Canon EF 1200mm f/5.6L");
          _lensTypeById.put(134, "Canon EF 600mm f/4L IS");
          _lensTypeById.put(135, "Canon EF 200mm f/1.8L");
          _lensTypeById.put(136, "Canon EF 300mm f/2.8L");
          _lensTypeById.put(137, "Canon EF 85mm f/1.2L or Sigma or Tamron Lens");
          _lensTypeById.put(138, "Canon EF 28-80mm f/2.8-4L");
          _lensTypeById.put(139, "Canon EF 400mm f/2.8L");
          _lensTypeById.put(140, "Canon EF 500mm f/4.5L");
          _lensTypeById.put(141, "Canon EF 500mm f/4.5L");
          _lensTypeById.put(142, "Canon EF 300mm f/2.8L IS");
          _lensTypeById.put(143, "Canon EF 500mm f/4L IS or Sigma Lens");
          _lensTypeById.put(144, "Canon EF 35-135mm f/4-5.6 USM");
          _lensTypeById.put(145, "Canon EF 100-300mm f/4.5-5.6 USM");
          _lensTypeById.put(146, "Canon EF 70-210mm f/3.5-4.5 USM");
          _lensTypeById.put(147, "Canon EF 35-135mm f/4-5.6 USM");
          _lensTypeById.put(148, "Canon EF 28-80mm f/3.5-5.6 USM");
          _lensTypeById.put(149, "Canon EF 100mm f/2 USM");
          _lensTypeById.put(150, "Canon EF 14mm f/2.8L or Sigma Lens");
          _lensTypeById.put(151, "Canon EF 200mm f/2.8L");
          _lensTypeById.put(152, "Canon EF 300mm f/4L IS or Sigma Lens");
          _lensTypeById.put(153, "Canon EF 35-350mm f/3.5-5.6L or Sigma or Tamron Lens");
          _lensTypeById.put(154, "Canon EF 20mm f/2.8 USM or Zeiss Lens");
          _lensTypeById.put(155, "Canon EF 85mm f/1.8 USM");
          _lensTypeById.put(156, "Canon EF 28-105mm f/3.5-4.5 USM or Tamron Lens");
          _lensTypeById.put(160, "Canon EF 20-35mm f/3.5-4.5 USM or Tamron or Tokina Lens");
          _lensTypeById.put(161, "Canon EF 28-70mm f/2.8L or Sigma or Tamron Lens");
          _lensTypeById.put(162, "Canon EF 200mm f/2.8L");
          _lensTypeById.put(163, "Canon EF 300mm f/4L");
          _lensTypeById.put(164, "Canon EF 400mm f/5.6L");
          _lensTypeById.put(165, "Canon EF 70-200mm f/2.8 L");
          _lensTypeById.put(166, "Canon EF 70-200mm f/2.8 L + 1.4x");
          _lensTypeById.put(167, "Canon EF 70-200mm f/2.8 L + 2x");
          _lensTypeById.put(168, "Canon EF 28mm f/1.8 USM or Sigma Lens");
          _lensTypeById.put(169, "Canon EF 17-35mm f/2.8L or Sigma Lens");
          _lensTypeById.put(170, "Canon EF 200mm f/2.8L II");
          _lensTypeById.put(171, "Canon EF 300mm f/4L");
          _lensTypeById.put(172, "Canon EF 400mm f/5.6L or Sigma Lens");
          _lensTypeById.put(173, "Canon EF 180mm Macro f/3.5L or Sigma Lens");
          _lensTypeById.put(174, "Canon EF 135mm f/2L or Other Lens");
          _lensTypeById.put(175, "Canon EF 400mm f/2.8L");
          _lensTypeById.put(176, "Canon EF 24-85mm f/3.5-4.5 USM");
          _lensTypeById.put(177, "Canon EF 300mm f/4L IS");
          _lensTypeById.put(178, "Canon EF 28-135mm f/3.5-5.6 IS");
          _lensTypeById.put(179, "Canon EF 24mm f/1.4L");
          _lensTypeById.put(180, "Canon EF 35mm f/1.4L or Other Lens");
          _lensTypeById.put(181, "Canon EF 100-400mm f/4.5-5.6L IS + 1.4x or Sigma Lens");
          _lensTypeById.put(182, "Canon EF 100-400mm f/4.5-5.6L IS + 2x or Sigma Lens");
          _lensTypeById.put(183, "Canon EF 100-400mm f/4.5-5.6L IS or Sigma Lens");
          _lensTypeById.put(184, "Canon EF 400mm f/2.8L + 2x");
          _lensTypeById.put(185, "Canon EF 600mm f/4L IS");
          _lensTypeById.put(186, "Canon EF 70-200mm f/4L");
          _lensTypeById.put(187, "Canon EF 70-200mm f/4L + 1.4x");
          _lensTypeById.put(188, "Canon EF 70-200mm f/4L + 2x");
          _lensTypeById.put(189, "Canon EF 70-200mm f/4L + 2.8x");
          _lensTypeById.put(190, "Canon EF 100mm f/2.8 Macro USM");
          _lensTypeById.put(191, "Canon EF 400mm f/4 DO IS");
          _lensTypeById.put(193, "Canon EF 35-80mm f/4-5.6 USM");
          _lensTypeById.put(194, "Canon EF 80-200mm f/4.5-5.6 USM");
          _lensTypeById.put(195, "Canon EF 35-105mm f/4.5-5.6 USM");
          _lensTypeById.put(196, "Canon EF 75-300mm f/4-5.6 USM");
          _lensTypeById.put(197, "Canon EF 75-300mm f/4-5.6 IS USM");
          _lensTypeById.put(198, "Canon EF 50mm f/1.4 USM or Zeiss Lens");
          _lensTypeById.put(199, "Canon EF 28-80mm f/3.5-5.6 USM");
          _lensTypeById.put(200, "Canon EF 75-300mm f/4-5.6 USM");
          _lensTypeById.put(201, "Canon EF 28-80mm f/3.5-5.6 USM");
          _lensTypeById.put(202, "Canon EF 28-80mm f/3.5-5.6 USM IV");
          _lensTypeById.put(208, "Canon EF 22-55mm f/4-5.6 USM");
          _lensTypeById.put(209, "Canon EF 55-200mm f/4.5-5.6");
          _lensTypeById.put(210, "Canon EF 28-90mm f/4-5.6 USM");
          _lensTypeById.put(211, "Canon EF 28-200mm f/3.5-5.6 USM");
          _lensTypeById.put(212, "Canon EF 28-105mm f/4-5.6 USM");
          _lensTypeById.put(213, "Canon EF 90-300mm f/4.5-5.6 USM or Tamron Lens");
          _lensTypeById.put(214, "Canon EF-S 18-55mm f/3.5-5.6 USM");
          _lensTypeById.put(215, "Canon EF 55-200mm f/4.5-5.6 II USM");
          _lensTypeById.put(217, "Tamron AF 18-270mm f/3.5-6.3 Di II VC PZD");
          _lensTypeById.put(224, "Canon EF 70-200mm f/2.8L IS");
          _lensTypeById.put(225, "Canon EF 70-200mm f/2.8L IS + 1.4x");
          _lensTypeById.put(226, "Canon EF 70-200mm f/2.8L IS + 2x");
          _lensTypeById.put(227, "Canon EF 70-200mm f/2.8L IS + 2.8x");
          _lensTypeById.put(228, "Canon EF 28-105mm f/3.5-4.5 USM");
          _lensTypeById.put(229, "Canon EF 16-35mm f/2.8L");
          _lensTypeById.put(230, "Canon EF 24-70mm f/2.8L");
          _lensTypeById.put(231, "Canon EF 17-40mm f/4L");
          _lensTypeById.put(232, "Canon EF 70-300mm f/4.5-5.6 DO IS USM");
          _lensTypeById.put(233, "Canon EF 28-300mm f/3.5-5.6L IS");
          _lensTypeById.put(234, "Canon EF-S 17-85mm f/4-5.6 IS USM or Tokina Lens");
          _lensTypeById.put(235, "Canon EF-S 10-22mm f/3.5-4.5 USM");
          _lensTypeById.put(236, "Canon EF-S 60mm f/2.8 Macro USM");
          _lensTypeById.put(237, "Canon EF 24-105mm f/4L IS");
          _lensTypeById.put(238, "Canon EF 70-300mm f/4-5.6 IS USM");
          _lensTypeById.put(239, "Canon EF 85mm f/1.2L II");
          _lensTypeById.put(240, "Canon EF-S 17-55mm f/2.8 IS USM");
          _lensTypeById.put(241, "Canon EF 50mm f/1.2L");
          _lensTypeById.put(242, "Canon EF 70-200mm f/4L IS");
          _lensTypeById.put(243, "Canon EF 70-200mm f/4L IS + 1.4x");
          _lensTypeById.put(244, "Canon EF 70-200mm f/4L IS + 2x");
          _lensTypeById.put(245, "Canon EF 70-200mm f/4L IS + 2.8x");
          _lensTypeById.put(246, "Canon EF 16-35mm f/2.8L II");
          _lensTypeById.put(247, "Canon EF 14mm f/2.8L II USM");
          _lensTypeById.put(248, "Canon EF 200mm f/2L IS or Sigma Lens");
          _lensTypeById.put(249, "Canon EF 800mm f/5.6L IS");
          _lensTypeById.put(250, "Canon EF 24mm f/1.4L II or Sigma Lens");
          _lensTypeById.put(251, "Canon EF 70-200mm f/2.8L IS II USM");
          _lensTypeById.put(252, "Canon EF 70-200mm f/2.8L IS II USM + 1.4x");
          _lensTypeById.put(253, "Canon EF 70-200mm f/2.8L IS II USM + 2x");
          _lensTypeById.put(254, "Canon EF 100mm f/2.8L Macro IS USM");
          _lensTypeById.put(255, "Sigma 24-105mm f/4 DG OS HSM | A or Other Sigma Lens");
          _lensTypeById.put(488, "Canon EF-S 15-85mm f/3.5-5.6 IS USM");
          _lensTypeById.put(489, "Canon EF 70-300mm f/4-5.6L IS USM");
          _lensTypeById.put(490, "Canon EF 8-15mm f/4L Fisheye USM");
          _lensTypeById.put(491, "Canon EF 300mm f/2.8L IS II USM");
          _lensTypeById.put(492, "Canon EF 400mm f/2.8L IS II USM");
          _lensTypeById.put(493, "Canon EF 500mm f/4L IS II USM or EF 24-105mm f4L IS USM");
          _lensTypeById.put(494, "Canon EF 600mm f/4.0L IS II USM");
          _lensTypeById.put(495, "Canon EF 24-70mm f/2.8L II USM");
          _lensTypeById.put(496, "Canon EF 200-400mm f/4L IS USM");
          _lensTypeById.put(499, "Canon EF 200-400mm f/4L IS USM + 1.4x");
          _lensTypeById.put(502, "Canon EF 28mm f/2.8 IS USM");
          _lensTypeById.put(503, "Canon EF 24mm f/2.8 IS USM");
          _lensTypeById.put(504, "Canon EF 24-70mm f/4L IS USM");
          _lensTypeById.put(505, "Canon EF 35mm f/2 IS USM");
          _lensTypeById.put(506, "Canon EF 400mm f/4 DO IS II USM");
          _lensTypeById.put(507, "Canon EF 16-35mm f/4L IS USM");
          _lensTypeById.put(508, "Canon EF 11-24mm f/4L USM");
          _lensTypeById.put(747, "Canon EF 100-400mm f/4.5-5.6L IS II USM");
          _lensTypeById.put(750, "Canon EF 35mm f/1.4L II USM");
          _lensTypeById.put(4142, "Canon EF-S 18-135mm f/3.5-5.6 IS STM");
          _lensTypeById.put(4143, "Canon EF-M 18-55mm f/3.5-5.6 IS STM or Tamron Lens");
          _lensTypeById.put(4144, "Canon EF 40mm f/2.8 STM");
          _lensTypeById.put(4145, "Canon EF-M 22mm f/2 STM");
          _lensTypeById.put(4146, "Canon EF-S 18-55mm f/3.5-5.6 IS STM");
          _lensTypeById.put(4147, "Canon EF-M 11-22mm f/4-5.6 IS STM");
          _lensTypeById.put(4148, "Canon EF-S 55-250mm f/4-5.6 IS STM");
          _lensTypeById.put(4149, "Canon EF-M 55-200mm f/4.5-6.3 IS STM");
          _lensTypeById.put(4150, "Canon EF-S 10-18mm f/4.5-5.6 IS STM");
          _lensTypeById.put(4152, "Canon EF 24-105mm f/3.5-5.6 IS STM");
          _lensTypeById.put(4153, "Canon EF-M 15-45mm f/3.5-6.3 IS STM");
          _lensTypeById.put(4154, "Canon EF-S 24mm f/2.8 STM");
          _lensTypeById.put(4156, "Canon EF 50mm f/1.8 STM");
          _lensTypeById.put(36912, "Canon EF-S 18-135mm f/3.5-5.6 IS USM");
          _lensTypeById.put(65535, "N/A");
      }
  }
  