exif class added (taken from opie-eye_slave and more c++ like reworked)

it is used in oimageview while loading jpegs checking BEFORE loading if the
image should be scaled loaded.
ToDo: documentation of the interface, remove it from opie-eye_slave (it should
use of course the library version)

1 files changed, 139 insertions, 0 deletions

diff --git a/libopie2/opiemm/opieexif.h b/libopie2/opiemm/opieexif.h
new file mode 100644
index 0000000..efaed71
--- a/dev/null
+++ b/libopie2/opiemm/opieexif.h
@@ -0,0 +1,139 @@
+#ifndef _OPIE_EXIF_H
+#define _OPIE_EXIF_H
+
+#include <qt.h>
+#include <qstring.h>
+#include <qimage.h>
+#include <qfile.h>
+
+#include <time.h>
+
+namespace Opie { namespace MM {
+
+#ifndef uchar
+typedef unsigned char uchar;
+#endif
+
+//#define MAX_SECTIONS 20
+//#define PSEUDO_IMAGE_MARKER 0x123; // Extra value.
+
+//! Class for reading exif data from images
+/*!
+ * This class is mostly used inside OImageScrollView for testing jpegs headers for a faster
+ * loading and scaling. It is taken from libexif and converted into an C++ structure.
+ *
+ * \see OImageScrollView
+ * \since 1.2
+ */
+class ExifData {
+public:
+    enum ReadMode_t {
+        READ_EXIF = 1,
+        READ_IMAGE = 2,
+        READ_ALL = 3
+    };
+
+    //--------------------------------------------------------------------------
+    // This structure is used to store jpeg file sections in memory.
+    struct Section_t {
+        uchar *  Data;
+        int      Type;
+        unsigned Size;
+    };
+
+    struct TagTable_t {
+        unsigned short Tag;
+        const char*const Desc;
+    };
+
+private:
+    static const int MAX_SECTIONS=20;
+    static const unsigned int PSEUDO_IMAGE_MARKER=0x123;
+    Section_t Sections[MAX_SECTIONS];
+
+    QString CameraMake;
+    QString CameraModel;
+    QString DateTime;
+    int   Orientation;
+    int   Height, Width;
+    int   ExifImageLength, ExifImageWidth;
+    int   IsColor;
+    int   Process;
+    int   FlashUsed;
+    float FocalLength;
+    float ExposureTime;
+    float ApertureFNumber;
+    float Distance;
+    int    Whitebalance;
+    int    MeteringMode;
+    float CCDWidth;
+    float ExposureBias;
+    int   ExposureProgram;
+    int   ISOequivalent;
+    int   CompressionLevel;
+    QString UserComment;
+    QString Comment;
+    QImage Thumbnail;
+
+    unsigned char * LastExifRefd;
+    int ExifSettingsLength;
+    double FocalplaneXRes;
+    double FocalplaneUnits;
+    int MotorolaOrder;
+    int SectionsRead;
+
+    int ReadJpegSections (QFile & infile, ReadMode_t ReadMode);
+    void DiscardData(void);
+    int Get16u(void * Short);
+    int Get32s(void * Long);
+    unsigned Get32u(void * Long);
+    double ConvertAnyFormat(void * ValuePtr, int Format);
+    void ProcessExifDir(unsigned char * DirStart, unsigned char * OffsetBase, unsigned ExifLength);
+    void process_COM (const uchar * Data, int length);
+    void process_SOFn (const uchar * Data, int marker);
+    int Get16m(const void * Short);
+    void process_EXIF(unsigned char * CharBuf, unsigned int length);
+    int Exif2tm(struct ::tm * timeptr, char * ExifTime);
+
+public:
+    //! Contructor for initialising
+    ExifData();
+    //! destructor
+    virtual ~ExifData();
+    //! scan a given file
+    /*!
+     * try to scan the EXIF data of a image file
+     * \param aFile the file to scan
+     * \return true if success, otherwise false
+     */
+    bool scan(const QString &aFile);
+    QString getCameraMake() { return CameraMake; }
+    QString getCameraModel() { return CameraModel; }
+    QString getDateTime() { return DateTime; }
+    int getOrientation() { return Orientation; }
+    int getHeight() { return Height; }
+    int getWidth() { return Width; }
+    int getIsColor() { return IsColor; }
+    int getProcess() { return Process; }
+    int getFlashUsed() { return FlashUsed; }
+    float getFocalLength() { return FocalLength; }
+    float getExposureTime() { return ExposureTime; }
+    float getApertureFNumber() { return ApertureFNumber; }
+    float getDistance() { return Distance; }
+    int getWhitebalance() { return Whitebalance; }
+    int getMeteringMode() { return MeteringMode; }
+    float getCCDWidth() { return CCDWidth; }
+    float getExposureBias() { return ExposureBias; }
+    int getExposureProgram() { return ExposureProgram; }
+    int getISOequivalent() { return ISOequivalent; }
+    int getCompressionLevel() { return CompressionLevel; }
+    QString getUserComment() { return UserComment; }
+    QString getComment() { return Comment; }
+    QImage getThumbnail();
+    bool isThumbnailSane();
+    bool isNullThumbnail() { return !isThumbnailSane(); }
+};
+
+}
+}
+#endif