/// <summary>
/// Return Exif thumbnail for jpegs.
/// </summary>
/// <param name="fileName">Jpeg filename</param>
/// <returns>Bitmap, null if anything goes wrong</returns>
protected static Bitmap GetExifThumbnail(string fileName)
{
var s = Path.GetExtension(fileName);
if (s == null || !File.Exists(fileName)) return null;
var ext = s.ToLower();
if (!IsJpeg(ext)) return null;
var reader = new ExifReader(fileName);
var bitmapBytes = reader.GetJpegThumbnailBytes();
return bitmapBytes != null && bitmapBytes.Length > 0 ? new Bitmap(new MemoryStream(bitmapBytes)) : null;
}
private void DisplayThumbnail(ExifReader reader)
{
var thumbnailBytes = reader.GetJpegThumbnailBytes();
uiThumbnailPictureBox.Image = null;
if (thumbnailBytes != null)
{
using (var stream = new MemoryStream(thumbnailBytes))
{
uiThumbnailPictureBox.Image = Image.FromStream(stream);
}
}
}
private void btnPopulate_Click(object sender, EventArgs e)
{
if (!File.Exists(txtFileName.Text))
{
MessageBox.Show(this, "Please enter a valid filename", "File not found", MessageBoxButtons.OK);
return;
}
try
{
using (var reader = new ExifReader(txtFileName.Text))
{
// Get the image thumbnail (if present)
var thumbnailBytes = reader.GetJpegThumbnailBytes();
if (thumbnailBytes == null)
pictureBoxThumbnail.Image = null;
else
{
using (var stream = new MemoryStream(thumbnailBytes))
pictureBoxThumbnail.Image = Image.FromStream(stream);
}
// To read a single field, use code like this:
/*
DateTime datePictureTaken;
if (reader.GetTagValue(ExifTags.DateTimeDigitized, out datePictureTaken))
{
MessageBox.Show(this, string.Format("The picture was taken on {0}", datePictureTaken), "Image information", MessageBoxButtons.OK);
}
*/
// Parse through all available fields and generate key-value labels
var props = Enum.GetValues(typeof (ExifTags)).Cast<ushort>().Select(tagID =>
{
object val;
if (reader.GetTagValue(tagID, out val))
{
// Special case - some doubles are encoded as TIFF rationals. These
// items can be retrieved as 2 element arrays of {numerator, denominator}
if (val is double)
{
int[] rational;
if (reader.GetTagValue(tagID, out rational))
val = string.Format("{0} ({1}/{2})", val, rational[0], rational[1]);
}
return string.Format("{0}: {1}", Enum.GetName(typeof (ExifTags), tagID), RenderTag(val));
}
return null;
}).Where(x => x != null).ToArray();
txtFields.Text = string.Join("\r\n", props);
}
}
catch (Exception ex)
{
// Something didn't work!
MessageBox.Show(this, ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
private void btnPopulate_Click(object sender, EventArgs e)
{
if (!File.Exists(txtFileName.Text))
{
MessageBox.Show(this, "Please enter a valid filename", "File not found", MessageBoxButtons.OK);
return;
}
ExifReader reader = null;
try
{
reader = new ExifReader(txtFileName.Text);
// Get the image thumbnail (if present)
var thumbnailBytes = reader.GetJpegThumbnailBytes();
if (thumbnailBytes == null)
pictureBoxThumbnail.Image = null;
else
{
using (var stream = new MemoryStream(thumbnailBytes))
pictureBoxThumbnail.Image = Image.FromStream(stream);
}
// To read a single field, use code like this:
/*
DateTime datePictureTaken;
if (reader.GetTagValue<DateTime>(ExifTags.DateTimeDigitized, out datePictureTaken))
{
MessageBox.Show(this, string.Format("The picture was taken on {0}", datePictureTaken), "Image information", MessageBoxButtons.OK);
}
*/
// Parse through all available fields
string props = "";
foreach (ushort tagID in Enum.GetValues(typeof(ExifTags)))
{
object val;
if (reader.GetTagValue(tagID, out val))
{
// Arrays don't render well without assistance.
string renderedTag;
if (val is Array)
{
renderedTag = "";
foreach (object item in (Array)val)
renderedTag += item + ",";
renderedTag = renderedTag.Substring(0, renderedTag.Length - 1);
}
else
renderedTag = val.ToString();
props += string.Format("{0}:{1}\r\n", Enum.GetName(typeof(ExifTags), tagID), renderedTag);
}
}
// Remove the last carriage return
props = props.Substring(0, props.Length - 2);
txtFields.Text = props;
}
catch (Exception ex)
{
// Something didn't work!
MessageBox.Show(this, ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
if (reader != null)
reader.Dispose();
}
}
