EXIF is a common form of meta-data that is embedded in images, typically by digital cameras to provide photographic information.



ImageEn supports EXIF for the following formats (* indicated reading only):
◼JPEG
◼TIFF
◼PNG (from "eXIf", "iTXt", "zTXt" and "tEXt" chunks) *
◼PSD
◼HDP
◼Camera RAW *

If an image contains EXIF data, EXIF_HasEXIFData will be true after loading. Set EXIF_HasEXIFData to true, if you add EXIF data to an image, or set to false to clear EXIF data.

Demo

Demos\InputOutput\EXIF\EXIF.dpr

General EXIF Tags

Photographic EXIF Tags

GPS EXIF Tags

EXIF Methods
◼Inject EXIF into a TIFF image using InjectTIFFEXIF or JPEG image using InjectJpegEXIF (to avoid resaving the image)
◼To determine if a file type supports EXIF use SupportsInfo
◼Clear the EXIF from a file using ResetInfo
◼To use the embedded thumbnail in EXIF data to speed up thumbnail display in TImageEnMView, you can enable EnableLoadEXIFThumbnails
◼You can use the TIEMetaListView to display and edit EXIF fields

Examples

label1.Caption := 'Horz. Resolution: ' + ImageEnView1.IO.Params.EXIF_XResolution2;
label2.Caption := 'Vert. Resolution: ' + ImageEnView1.IO.Params.EXIF_YResolution2;
label3.Caption := 'Exposure Time: ' + ImageEnView1.IO.Params.EXIF_ExposureTime2;
label4.Caption := 'F-Number: ' + ImageEnView1.IO.Params.EXIF_FNumber2;
label5.Caption := 'Shutter Speed: ' + ImageEnView1.IO.Params.EXIF_ShutterSpeedValue2;
label6.Caption := 'Aperture: ' + ImageEnView1.IO.Params.EXIF_ApertureValue2;
label7.Caption := 'Max Aperture: ' + ImageEnView1.IO.Params.EXIF_MaxApertureValue2;

// Update EXIF date for the current file
ImageEnView1.IO.Params.EXIF_DateTime2 := Now;
ImageEnView1.IO.Params.EXIF_DateTimeOriginal2 := Now;
ImageEnView1.IO.Params.EXIF_HasEXIFData  := True;
ImageEnView1.IO.InjectJpegEXIF( ImageEnView1.IO.Params.Filename );

// Remove EXIF data from image.jpg
ImageEnView1.IO.Params.EXIF_HasExifData := False;
ImageEnView1.IO.SaveToFile('D:\image.jpg'); // Or use InjectJpegEXIF to avoid resaving the image

// Update the GPS EXIF data in a file
io := TImageEnIO.create(nil);
try
  io.ParamsFromFile( FilenameStr );

  io.Params.EXIF_GPSLatitude  := GPSLatitudeFloat;
  io.Params.EXIF_GPSLongitude := GPSLongitudeFloat;
  io.Params.EXIF_GPSVersionID := GPS_Version_ID;
  io.Params.EXIF_HasEXIFData  := True;

  io.InjectJpegEXIF( FilenameStr );
finally
  io.Free;
end;

// Write EXIF GSP data to the current file
ImageEnView1.IO.Params.EXIF_GPSLatitude  := StrToFloat( edtEXIF_GPSLatitude.Text );
ImageEnView1.IO.Params.EXIF_GPSLongitude := StrToFloat( edtEXIF_GPSLongitude.Text );
ImageEnView1.IO.Params.EXIF_GPSVersionID := GPS_Version_ID;
ImageEnView1.IO.InjectJpegEXIF('D:\GPSStamped.jpg');

// Write a comment to the file
ImageEnView1.IO.LoadFromFile('C:\input.jpg');
ImageEnView1.IO.Params.EXIF_UserComment := 'Hello World!';
ImageEnView1.IO.Params.EXIF_UserCommentCode := IEExifUserCommentCode_Unicode;
ImageEnView1.IO.Params.EXIF_HasEXIFData := true;
ImageEnView1.IO.SaveToFileTIFF('D:\test.tiff');

// Read back the comment
ImageEnView1.IO.LoadFromFileTIFF('D:\test.tiff');
ShowMessage( ImageEnView1.IO.Params.EXIF_UserComment );

See Also

◼ResetEXIF
◼GetMetaData
◼#EXIF Tags

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