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 New! JPEG Repair Service
JPEG is a widely used format to store digital images. Most smart-phones, digital cameras, digital DSLRs (for previews) store digital photos as .JPG files. Digital photos in such devices are commonly stored on memory cards. Unfortunately both memory cards and JPG image files are very prone to corruption.

Common corruption:

Memory card corruption: Common causes for memory card corruption are the improper removal of cards and errors during data transfer.

JPG file corruption: Due to the stucture of JPG files (a linked list of so called markers) and the method of compression of image data, JPGs are susceptible to data corruption.

JPEG corruption after data recovery: Most common corruption after data recovery is incomplete files due to file fragmentation. The file is simply incomplete, part of the data is missing.

We offer a service to manually repair corrupt JPEG files. Often the human eye is indispensable when it comes to spotting and repairing corruption in the image bit stream. We can fix JPGs that automatic JPEG Recovery software can not. Repairing JPEGs is a very labor intensive procedure.

jpeg repair stages 
Different stages of repairing a JPEG image bit stream

We can fix:

Invalid JPEG Marker Type
Unknown JPEG Markers
Corrupt JPEG headers
Color Shift
Pixel Shift
Partially Grey JPG files
How does it work? JPEG Repair Process.
We examine the JPEG.
We first check the JPG for structural damage. If the file will not 'load' or render at all using an image viewer, there is often structural damage (corrupt header or markers). We visually inspect the image file. If the image loads but is completely distorted, we may be dealing with a corrupt Huffman table.
We edit the image stream.
By a process of trial and error we edit the actual image data. Due to the method of image compression, an error in the image data will influence all data after that point. Depending on the damage we observe we will typically add, remove or edit data.
Post repair touch-up.
Due to us adding/removing data to/from the image data we inevitably create collateral damage, typically small greyed blocks (zero data). We touch up those areas using a process called inpainting: Using surrounding data to fill in the blank spots.
Huffman table corrupt Header Repair.
In case of header corruption an image may not load at all, or it may be completely distorted (in example shown: bad Huffman table). To repair a corrupt header we need an intact sample JPEG that was shot using the same device. The sample needs to be 'shot' with the exact same settings as the corrupt image (dimensions, quality etc.).
Ordering and Pricing

As JPEG File Repair and even just the diagnosis is a labor intensive process we need to charge a small, to be payed in advance, non-refundable, startup fee. If you want to order our service, please proceed as follows:

1. Order Startup-Fee. Then wait for our email with instructions to sent us the corrupt JPG files. The Startup fee already includes ONE image repair.

2. Wait for us to contact you. For each additional photo we repair, we charge one ‘JPEG Repair Unit’. You only pay for the images that we actually manage to repair! Once we have repaired your JPEGs, we contact you by email to inform you on the amount of images we were able to repair. Once you purchased the additional UNITS (one per repaired JPG) we sent you the repaired images. Only order JPEG Repair Units AFTER we have contacted you, and informed you about the number of files we repaired. Typically you will hear from us within two working days.

If we can not repair the JPEG image we may be able to extract lower resolution preview JPGs from the corrupt file (often 640 x 480). In that case, we will contact you and if you desire you can purchase the preview(s).

Item Remarks Purchase
Startup-Fee Includes one JPEG – Non Refundable! 20 USD
JPEG Repair Unit No cure, no pay. Adjust quantity as needed 10 USD
Lower Res. Preview Free tool available now  

 








Example: You want us to repair 6 digital photos. You then order Startup-Fee. We contact you and we ask you to either email us or upload the images. We will start working on your files.

Assume we fix all six images. We will email you to notify you. You order five JPEG repair Units (one was already included with startup-fee), we deliver the repaired files.

JPEG Repair Toolkit
To make our lives easier we use a JPEG Repair Toolkit which aids us in repairing corrupt JPEG files.

The toolkit is under constant development and currently consists of three modules:
  • ChkJPG: Checks the structure of the JPG file much like Chkdsk checks your file system. It walks the chain of JPEG markers. It also allows us to extract and insert headers and preview JPGs that are embedded inside the JPG file.
  • JPG-Patch: A binary file editor that allows us to edit the JPG file while showing us a preview of the effects of the edits. We can add data, substract data and modify data.
  • Inpainter: Used to touch up repaired images. It automatically fills in damaged areas using data in the area surrounding the damaged spots.

Original repairs were done using an ordinary binary file editor. This required constant switching between the editor and an image viewer: Edit file > save file> open saved file in viewer and evaluate result. Repeat until fixed.

Also fixing headers was done using the binary editor. At some point we started developing specialized tools for the different tasks. More details are on www.disktuna.com

Maybe we can make a DIY JPEG Repair Toolkit available in the future.

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