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Programming / Metadata / Accessing image metadata in direct access mode

Accessing image metadata in direct access mode

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GdPicture offers an image parsing mechanism, that allows direct access to image properties such as metadata, ICC profiles and embedded thumbnails without decoding pixels. This feature is particularly useful if you need to quickly extract document information without the need to edit and render it on the screen.

Below is an example of fast XMP, iptc, gps and exif metadata extraction from any kind of image supported by the toolkit.

Copy Code 
'We assume that GdPicture has been correctly installed and unlocked.

Dim oGdPictureImaging As New GdPictureImaging()

'Loading image in direct access mode.

Dim ImageID As Integer = oGdPictureImaging.CreateGdPictureImageFromFile("image.JPG", False, True)

If oGdPictureImaging.GetStat() = GdPictureStatus.OK Then

    Dim sb As New System.Text.StringBuilder()

    Dim exifTagsCount As Integer = oGdPictureImaging.TagCount(ImageID)

    Dim iptcTagsCount As Integer = oGdPictureImaging.IPTCCount(ImageID) 

    If exifTagsCount <> 0 Then

        'Handling EXIF tags.

        sb.Append("EXIF tags:" & vbCrLf & "-----------" & vbCrLf)

        For i As Integer = 1 To exifTagsCount

            Dim tagName As String = oGdPictureImaging.TagGetName(ImageID, i)

            Dim tagFormattedValue As String = oGdPictureImaging.TagGetValueString(ImageID, i)

            sb.Append(tagName + ": " + tagFormattedValue + vbCrLf)

        Next

    End If

    If iptcTagsCount <> 0 Then

        'Handling IPTC tags.

        sb.Append("IPTC tags:" & vbCrLf & "-----------" & vbCrLf)

        For i As Integer = 1 To iptcTagsCount

            Dim tagName As String = oGdPictureImaging.IPTCGetID(ImageID, i).ToString()

            Dim tagFormattedValue As String = oGdPictureImaging.IPTCGetValueString(ImageID, i)

            sb.Append(tagName + ": " + tagFormattedValue + vbLf)

        Next

    End If

    oGdPictureImaging.ReleaseGdPictureImage(ImageID)

    MessageBox.Show(sb.ToString(), "Metadata Example", MessageBoxButtons.OK, MessageBoxIcon.Information)

Else

    MessageBox.Show("The image can't be loaded. Status: " + oGdPictureImaging.GetStat().ToString(), "Metadata Example", MessageBoxButtons.OK, MessageBoxIcon.Error)

End If

oGdPictureImaging.Dispose()
Copy Code 
//We assume that GdPicture has been correctly installed and unlocked. 

GdPictureImaging oGdPictureImaging = new GdPictureImaging();

//Loading image in direct access mode.

int ImageID = oGdPictureImaging.CreateGdPictureImageFromFile("image.JPG", false, true);

if (oGdPictureImaging.GetStat() == GdPictureStatus.OK)

{

    System.Text.StringBuilder sb = new System.Text.StringBuilder();

    int exifTagsCount = oGdPictureImaging.TagCount(ImageID);

    int iptcTagsCount = oGdPictureImaging.IPTCCount(ImageID); 

    if (exifTagsCount != 0)

    {

        //Handling EXIF tags.

        sb.Append("EXIF tags:\n-----------\n");

        for (int i = 1; i <= exifTagsCount; i++)

        {

            string tagName = oGdPictureImaging.TagGetName(ImageID, i);

            string tagFormattedValue = oGdPictureImaging.TagGetValueString(ImageID, i);

            sb.Append(tagName + ": " + tagFormattedValue + "\n");

        }

    }

    if (iptcTagsCount != 0)

    {

        //Handling IPTC tags.

        sb.Append("IPTC tags:\n-----------\n");

        for (int i = 1; i <= iptcTagsCount; i++)

        {

            string tagName = oGdPictureImaging.IPTCGetID(ImageID, i).ToString();

            string tagFormattedValue = oGdPictureImaging.IPTCGetValueString(ImageID, i);

            sb.Append(tagName + ": " + tagFormattedValue + "\n");

        }

    }

    oGdPictureImaging.ReleaseGdPictureImage(ImageID);

    MessageBox.Show(sb.ToString(), "Metadata Example", MessageBoxButtons.OK, MessageBoxIcon.Information);

}

else

{

    MessageBox.Show("The image can't be loaded. Status: " + oGdPictureImaging.GetStat().ToString(), "Metadata Example", MessageBoxButtons.OK, MessageBoxIcon.Error);

}

oGdPictureImaging.Dispose();

Result: