Add Focal Plane X/Y resolution + GPS degree of precision.

Fixes #1.

demo.cpp

@@ -68,12 +68,15 @@ int main(int argc, char *argv[]) {
          result.GeoLocation.LonComponents.seconds,
          result.GeoLocation.LonComponents.direction);
   printf("GPS Altitude         : %f m\n", result.GeoLocation.Altitude);
+  printf("GPS Precision (DOP)  : %f\n", result.GeoLocation.DOP);
   printf("Lens min focal length: %f mm\n", result.LensInfo.FocalLengthMin);
   printf("Lens max focal length: %f mm\n", result.LensInfo.FocalLengthMax);
   printf("Lens f-stop min      : f/%.1f\n", result.LensInfo.FStopMin);
   printf("Lens f-stop max      : f/%.1f\n", result.LensInfo.FStopMax);
   printf("Lens make            : %s\n", result.LensInfo.Make.c_str());
   printf("Lens model           : %s\n", result.LensInfo.Model.c_str());
+  printf("Focal plane XRes     : %f\n", result.LensInfo.FocalPlaneXResolution);
+  printf("Focal plane YRes     : %f\n", result.LensInfo.FocalPlaneYResolution);
 
   return 0;
 }

exif.cpp

@@ -682,25 +682,45 @@ int easyexif::EXIFInfo::parseFromEXIFSegment(const unsigned char *buf,
             this->ImageHeight = result.val_short().front();
           break;
 
+        case 0xa20e:
+          // EXIF Focal plane X-resolution
+          if (result.format() == 5) {
+            this->LensInfo.FocalPlaneXResolution = result.val_rational()[0];
+          }
+          break;
+
+        case 0xa20f:
+          // EXIF Focal plane Y-resolution
+          if (result.format() == 5) {
+            this->LensInfo.FocalPlaneYResolution = result.val_rational()[0];
+          }
+          break;
+
         case 0xa405:
           // Focal length in 35mm film
           if (result.format() == 3)
             this->FocalLengthIn35mm = result.val_short().front();
           break;
+
         case 0xa432:
+          // Focal length and FStop.
           if (result.format() == 5) {
             this->LensInfo.FocalLengthMin = result.val_rational()[0];
             this->LensInfo.FocalLengthMax = result.val_rational()[1];
             this->LensInfo.FStopMin = result.val_rational()[2];
             this->LensInfo.FStopMax = result.val_rational()[3];
           }
           break;
+
         case 0xa433:
+          // Lens make.
           if (result.format() == 2) {
             this->LensInfo.Make = result.val_string();
           }
           break;
+
         case 0xa434:
+          // Lens model.
           if (result.format() == 2) {
             this->LensInfo.Model = result.val_string();
           }
@@ -784,12 +804,13 @@ int easyexif::EXIFInfo::parseFromEXIFSegment(const unsigned char *buf,
         case 5:
           // GPS altitude reference (below or above sea level)
           this->GeoLocation.AltitudeRef = *(buf + offs + 8);
-          if (1 == this->GeoLocation.AltitudeRef)
+          if (1 == this->GeoLocation.AltitudeRef) {
             this->GeoLocation.Altitude = -this->GeoLocation.Altitude;
+          }
           break;
 
         case 6:
-          // GPS altitude reference
+          // GPS altitude
           if (format == 5) {
             this->GeoLocation.Altitude = parse_value<Rational>(
                 buf + data + tiff_header_start, alignIntel);
@@ -798,6 +819,14 @@ int easyexif::EXIFInfo::parseFromEXIFSegment(const unsigned char *buf,
             }
           }
           break;
+
+        case 11:
+          // GPS degree of precision (DOP)
+          if (format == 5) {
+            this->GeoLocation.DOP = parse_value<Rational>(
+                buf + data + tiff_header_start, alignIntel);
+          }
+          break;
       }
       offs += 12;
     }
@@ -841,6 +870,7 @@ void easyexif::EXIFInfo::clear() {
   GeoLocation.Longitude = 0;
   GeoLocation.Altitude = 0;
   GeoLocation.AltitudeRef = 0;
+  GeoLocation.DOP = 0;
   GeoLocation.LatComponents.degrees = 0;
   GeoLocation.LatComponents.minutes = 0;
   GeoLocation.LatComponents.seconds = 0;
@@ -855,6 +885,8 @@ void easyexif::EXIFInfo::clear() {
   LensInfo.FocalLengthMin = 0;
   LensInfo.FStopMax = 0;
   LensInfo.FStopMin = 0;
+  LensInfo.FocalPlaneYResolution = 0;
+  LensInfo.FocalPlaneXResolution = 0;
   LensInfo.Make = "";
   LensInfo.Model = "";
 }

exif.h

@@ -1,5 +1,5 @@
 /**************************************************************************
-  exif.h  -- A simple ISO C++ library to parse basic EXIF 
+  exif.h  -- A simple ISO C++ library to parse basic EXIF
              information from a JPEG file.
 
   Based on the description of the EXIF file format at:
@@ -15,7 +15,7 @@
   ================
 
   2.2: Release December 2014
-       -- 
+       --
 
   2.1: Released July 2013
        -- fixed a bug where JPEGs without an EXIF SubIFD would not be parsed
@@ -31,25 +31,25 @@
        -- added GPS support
 
   1.0: Released 2010
-  
-  Redistribution and use in source and binary forms, with or without 
+
+  Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions are met:
 
-  -- Redistributions of source code must retain the above copyright notice, 
+  -- Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
-  -- Redistributions in binary form must reproduce the above copyright notice, 
-     this list of conditions and the following disclaimer in the documentation 
+  -- Redistributions in binary form must reproduce the above copyright notice,
+     this list of conditions and the following disclaimer in the documentation
    and/or other materials provided with the distribution.
 
-   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY EXPRESS 
-   OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 
-   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN 
-   NO EVENT SHALL THE FREEBSD PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 
-   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 
-   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
-   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 
-   OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
-   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, 
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY EXPRESS
+   OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
+   NO EVENT SHALL THE FREEBSD PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+   BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+   OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
    EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 #ifndef __EXIF_H
@@ -59,7 +59,7 @@
 
 namespace easyexif {
 
-// 
+//
 // Class responsible for storing and parsing EXIF information from a JPEG blob
 //
 class EXIFInfo {
@@ -74,15 +74,15 @@ class EXIFInfo {
   int parseFrom(const std::string &data);
 
   // Parsing function for an EXIF segment. This is used internally by parseFrom()
-  // but can be called for special cases where only the EXIF section is 
+  // but can be called for special cases where only the EXIF section is
   // available (i.e., a blob starting with the bytes "Exif\0\0").
   int parseFromEXIFSegment(const unsigned char *buf, unsigned len);
 
   // Set all data members to default values.
   void clear();
 
   // Data fields filled out by parseFrom()
-  char ByteAlign;                   // 0 = Motorola byte alignment, 1 = Intel 
+  char ByteAlign;                   // 0 = Motorola byte alignment, 1 = Intel
   std::string ImageDescription;     // Image description
   std::string Make;                 // Camera manufacturer's name
   std::string Model;                // Camera model
@@ -122,18 +122,21 @@ class EXIFInfo {
     double Longitude;                 // Image longitude expressed as decimal
     double Altitude;                  // Altitude in meters, relative to sea level
     char AltitudeRef;                 // 0 = above sea level, -1 = below sea level
+    double DOP;                       // GPS degree of precision (DOP)
     struct Coord_t {
       double degrees;
       double minutes;
       double seconds;
       char direction;
-    } LatComponents, LonComponents;   // Latitude, Longitude expressed in deg/min/sec 
+    } LatComponents, LonComponents;   // Latitude, Longitude expressed in deg/min/sec
   } GeoLocation;
   struct LensInfo_t {               // Lens information
     double FStopMin;                // Min aperture (f-stop)
     double FStopMax;                // Max aperture (f-stop)
     double FocalLengthMin;          // Min focal length (mm)
     double FocalLengthMax;          // Max focal length (mm)
+    double FocalPlaneXResolution;   // Focal plane X-resolution
+    double FocalPlaneYResolution;   // Focal plane Y-resolution
     std::string Make;               // Lens manufacturer
     std::string Model;              // Lens model
   } LensInfo;

test-images/down-mirrored.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 0.000000 mm
 GPS Latitude         : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Longitude        : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Altitude         : 0.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 0.000000 mm
 Lens max focal length: 0.000000 mm
 Lens f-stop min      : f/0.0
 Lens f-stop max      : f/0.0
 Lens make            : 
 Lens model           : 
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000

test-images/evil1.jpg.expected

@@ -0,0 +1,34 @@
+Camera make          : Canon
+Camera model         : Canon PowerShot S400
+Software             : Adobe Photoshop 7.0
+Bits per sample      : 0
+Image width          : 400
+Image height         : 300
+Image description    : 
+Image orientation    : 1
+Image copyright      : 
+Image date/time      : 2003:05:25 11:11:41
+Original date/time   : 2003:05:24 16:40:33
+Digitize date/time   : 2003:05:24 16:40:33
+Subsecond time       : 
+Exposure time        : 1/8 s
+F-stop               : f/2.8
+ISO speed            : 0
+Subject distance     : 0.000000 m
+Exposure bias        : 0.000000 EV
+Flash used?          : 1
+Metering mode        : 5
+Lens focal length    : 7.406250 mm
+35mm focal length    : 0 mm
+GPS Latitude         : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
+GPS Longitude        : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
+GPS Altitude         : 0.000000 m
+GPS Precision (DOP)  : 0.000000
+Lens min focal length: 0.000000 mm
+Lens max focal length: 0.000000 mm
+Lens f-stop min      : f/0.0
+Lens f-stop max      : f/0.0
+Lens make            : 
+Lens model           : 
+Focal plane XRes     : 8114.285714
+Focal plane YRes     : 8114.285714

test-images/lens_info.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 0.000000 mm
 GPS Latitude         : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Longitude        : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Altitude         : 0.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 10.000000 mm
 Lens max focal length: 400.000000 mm
 Lens f-stop min      : f/1.1
 Lens f-stop max      : f/1.2
 Lens make            : Lens Maker Inc.
 Lens model           : Lens Model mk I
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000

test-images/right.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 0.000000 mm
 GPS Latitude         : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Longitude        : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Altitude         : 0.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 0.000000 mm
 Lens max focal length: 0.000000 mm
 Lens f-stop min      : f/0.0
 Lens f-stop max      : f/0.0
 Lens make            : 
 Lens model           : 
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000

test-images/short-ascii-II.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 3.510000 mm
 GPS Latitude         : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Longitude        : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Altitude         : 0.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 0.000000 mm
 Lens max focal length: 0.000000 mm
 Lens f-stop min      : f/0.0
 Lens f-stop max      : f/0.0
 Lens make            : 
 Lens model           : 
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000

test-images/short-ascii-MM.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 21.300000 mm
 GPS Latitude         : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Longitude        : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Altitude         : 0.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 0.000000 mm
 Lens max focal length: 0.000000 mm
 Lens f-stop min      : f/0.0
 Lens f-stop max      : f/0.0
 Lens make            : 
 Lens model           : 
+Focal plane XRes     : 8114.285714
+Focal plane YRes     : 8114.285714

test-images/sony-alpha-6000.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 22.000000 mm
 GPS Latitude         : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Longitude        : 0.000000 deg (0.000000 deg, 0.000000 min, 0.000000 sec ?)
 GPS Altitude         : 0.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 16.000000 mm
 Lens max focal length: 50.000000 mm
 Lens f-stop min      : f/3.5
 Lens f-stop max      : f/5.6
 Lens make            : 
 Lens model           : E PZ 16-50mm F3.5-5.6 OSS
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000

test-images/test1.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 4.280000 mm
 GPS Latitude         : 37.885000 deg (37.000000 deg, 53.100000 min, 0.000000 sec N)
 GPS Longitude        : -122.622500 deg (122.000000 deg, 37.350000 min, 0.000000 sec W)
 GPS Altitude         : 122.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 0.000000 mm
 Lens max focal length: 0.000000 mm
 Lens f-stop min      : f/0.0
 Lens f-stop max      : f/0.0
 Lens make            : 
 Lens model           : 
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000

test-images/test2.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 4.280000 mm
 GPS Latitude         : 37.814667 deg (37.000000 deg, 48.880000 min, 0.000000 sec N)
 GPS Longitude        : -122.264167 deg (122.000000 deg, 15.850000 min, 0.000000 sec W)
 GPS Altitude         : 2.000000 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 0.000000 mm
 Lens max focal length: 0.000000 mm
 Lens f-stop min      : f/0.0
 Lens f-stop max      : f/0.0
 Lens make            : 
 Lens model           : 
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000

test-images/test3.jpg.expected

@@ -23,9 +23,12 @@ Lens focal length    : 4.280000 mm
 GPS Latitude         : 37.776333 deg (37.000000 deg, 46.580000 min, 0.000000 sec N)
 GPS Longitude        : -122.419667 deg (122.000000 deg, 25.180000 min, 0.000000 sec W)
 GPS Altitude         : 15.833345 m
+GPS Precision (DOP)  : 0.000000
 Lens min focal length: 0.000000 mm
 Lens max focal length: 0.000000 mm
 Lens f-stop min      : f/0.0
 Lens f-stop max      : f/0.0
 Lens make            : 
 Lens model           : 
+Focal plane XRes     : 0.000000
+Focal plane YRes     : 0.000000