How to recover exif thumbnail

[Aaryn]

To create thumbnail i used the program called system.drawing.image.getthumbnailimage. this program generally takes exif images directly from the camera. This program makes it easy to load thumbnail images on the server but while loading a large content on the server i lost that content due to some reason.

So i Just wanted to know weather i can recover that thumbnail...??

[Macarenas]

What is EXIF..??

EXIF stands for Exchangeable Image File Format, and is a standard for toring interchange information in image files, especially those using JPEG Compression. Most digital cameras now use the EXIF format. The format is part of the DCF standard created by JEITA to encourage interoperability between imaging devices.

The Exif image file specification stipulates the method of recording image data in files, and specifies the following
items:

• Structure of image data files,
  
  
• Tags used by this standard,
  
  
• Definition and management of format versions.

Features of the Exif image file specification include the following :

The file-recording format is based on existing formats. Compressed files are recorded as JPEG (ISO/IEC 10918-1) with application marker segments (APP1 and APP2) inserted. Uncompressed files are recorded in TIFF Rev. 6.0 format. The use of existing formats means files recorded using a DSC or related system can be read directly by commercial applications, and makes possible the use of functions for viewing and manipulating the images.

Related attribute information for both compressed and uncompressed files is stored in the tag information format defined in TIFF Rev. 6.0. Information specific to the camera system and not defined in TIFF is stored in private lags registered for Exif. The Exif image file specification also specifies the method for recording thumbnails. The reason for using the TIFF Rev. 6.0 tag format in the compressed file APP1 segment is to facilitate exchange of attribute data between Exif compressed and uncompressed files.

Compressed files can record extended data exceeding 64 Kbytes by dividing it into multiple APP2 segments. The APP2 segment is used when recording Flashpix extensions. Details of the Exif image file specification are given in Chapter 4 of this document.

[JonathanD]

How to recover the Exif data after editing...??

A free software available to save the lost Exif image. This is called ExifUtils and you can download from here

This is a program that work of the line of order in a console DOS. It doesn't have a convivial interface. You must type the orders, but it is not difficult and do not be afraid. Here how you can use.

Let's assume that you have a picture that original.jpg called, in the images folder on the root of your hard drive. Having it on Photoshop you have saved it had edited, such as edited.jpg and the exif data you want to save, especially while it was in the original.

The first step is the opening of the DOS console. The fastest way to do this that in Windows XP is it, click on "Start", you go on "RUN" and give cmd. Then you must to the file, in that you both pictures. Give CD \ and after CD pictures.

Now, I will give you the stages I to use to recover all the original Exif data. If you want more, you can consult the documentation of the software.

• Type exifedit /e a edited.jpg

The preceding order erases all the Exif data in the published file.

• Type exifcopy /o original.jpg edited.jpg

The previous command will copy all the Exif data of the original image in the image edited overwritting repeated any field possible.

• Type exifedit /s edited.jpg

That will make it possible to update the EXIF width and the height of the fields to make correspond real image of values.

• And finally type exifedit /t a edited.jpg

This will update and you the Thumbnail picture for the worked on file with the standard dimensions of 160x120 pixel.

And done. You have recover all the original Exif Image.