public void ReadTag(ushort tag, ExifHeader headerType, ExifPhoto photo)
{
var currentPos = _jpegFileReader.BaseStream.Position;
var fieldtype = (ExifFieldType)_binaryReader.ReadUInt16();
var length = _binaryReader.ReadUInt32();
var value = _binaryReader.ReadUInt32();
switch (fieldtype) {
case ExifFieldType.AsciiStrings:
SeekToTiffHeaderRelativeOffset(value);
photo.SetMatchingProperty(tag, headerType, _binaryReader.ReadString((int)length));
break;
case ExifFieldType.UnsignedRational:
SeekToTiffHeaderRelativeOffset(value);
photo.SetMatchingProperty(tag, headerType, _binaryReader.ReadUnsignedRational());
break;
case ExifFieldType.UnsignedLong:
photo.SetMatchingProperty(tag, headerType, value);
break;
}
_jpegFileReader.BaseStream.Seek(currentPos + 2 + 4 + 4, SeekOrigin.Begin);
}
public void ReadTag(ushort tag, ExifHeader headerType, ExifPhoto photo)
{
var currentPos = _jpegFileReader.BaseStream.Position;
var fieldtype = (ExifFieldType)_binaryReader.ReadUInt16();
var length = _binaryReader.ReadUInt32();
var value = _binaryReader.ReadUInt32();
switch (fieldtype)
{
case ExifFieldType.AsciiStrings:
SeekToTiffHeaderRelativeOffset(value);
photo.SetMatchingProperty(tag, headerType, _binaryReader.ReadString((int)length));
break;
case ExifFieldType.UnsignedRational:
SeekToTiffHeaderRelativeOffset(value);
photo.SetMatchingProperty(tag, headerType, _binaryReader.ReadUnsignedRational());
break;
case ExifFieldType.UnsignedLong:
photo.SetMatchingProperty(tag, headerType, value);
break;
}
_jpegFileReader.BaseStream.Seek(currentPos + 2 + 4 + 4, SeekOrigin.Begin);
}
public void SetMatchingProperty(uint tag, ExifHeader headerType, object value)
{
var exifAttribute = new ExifAttribute(tag, headerType);
if (!_exifAttributesCache.ContainsKey(exifAttribute)) return;
var propertyName = _exifAttributesCache[exifAttribute];
var propertyInfo = this.GetType().GetProperty(propertyName);
propertyInfo.SetValue(this, value, null);
_unsetProperties[headerType]--; //this is based on the assumption that Exif tags in the jpg are unique
}
public void ReadIFDHeader(ExifHeader headerType, uint headerPosition, ExifPhoto photo)
{
SeekToTiffHeaderRelativeOffset(headerPosition);
var numberOfTags = _binaryReader.ReadUInt16();
for (var i = 0; i < numberOfTags; i++) {
var tag = _binaryReader.ReadUInt16();
if (ExifPhoto.HasMatchingProperty(tag, headerType)) {
ReadTag(tag, headerType, photo);
if (!photo.HasUnsetProperties(headerType)) break;
} else
MoveToTheNextTag();
}
}
public void SetMatchingProperty(uint tag, ExifHeader headerType, object value)
{
var exifAttribute = new ExifAttribute(tag, headerType);
if (!_exifAttributesCache.ContainsKey(exifAttribute))
{
return;
}
var propertyName = _exifAttributesCache[exifAttribute];
var propertyInfo = this.GetType().GetProperty(propertyName);
propertyInfo.SetValue(this, value, null);
_unsetProperties[headerType]--; //this is based on the assumption that Exif tags in the jpg are unique
}
public void ReadIFDHeader(ExifHeader headerType, uint headerPosition, ExifPhoto photo)
{
SeekToTiffHeaderRelativeOffset(headerPosition);
var numberOfTags = _binaryReader.ReadUInt16();
for (var i = 0; i < numberOfTags; i++)
{
var tag = _binaryReader.ReadUInt16();
if (ExifPhoto.HasMatchingProperty(tag, headerType))
{
ReadTag(tag, headerType, photo);
if (!photo.HasUnsetProperties(headerType))
{
break;
}
}
else
{
MoveToTheNextTag();
}
}
}
public ExifAttribute(uint tag, ExifHeader exifHeader)
{
Tag = tag;
ExifHeader = exifHeader;
}
public bool HasUnsetProperties(ExifHeader headerType) => _unsetProperties[headerType] > 0;
public static bool HasMatchingProperty(uint tag, ExifHeader headerType)
{
var exifAttribute = new ExifAttribute(tag, headerType);
return _exifAttributesCache.ContainsKey(exifAttribute);
}
public bool HasUnsetProperties(ExifHeader headerType) => _unsetProperties[headerType] > 0;
public static bool HasMatchingProperty(uint tag, ExifHeader headerType)
{
var exifAttribute = new ExifAttribute(tag, headerType);
return(_exifAttributesCache.ContainsKey(exifAttribute));
}
public ExifAttribute(uint tag, ExifHeader exifHeader)
{
Tag = tag;
ExifHeader = exifHeader;
}
