Common JPEG Image Errors

Photo image files may have a variety of damages. It may be that the header of the JPEG file is corrupt, or sometimes it may be possible that the JPG markers are invalid. Chances of bit errors in JPEG are also there. In this article we will discuss instances of corrupt JPEG and their possible solutions.

 

Color error in a JPEG scan

Scan of JPG formatted images can have single or multiple bit and byte errors. Most of image file data is in order, but even a small damage in some part creates all the other subsequent parts to show wrong data. This is because information in each part is depended on the information in the previous part. The problem can be created due to erroneous storage medium or faulty transmission.

 

JPEG images are stored as Baseline by default. In this type, images are stored line by line from top to bottom. Corruption in the Baseline JPEG can not be neglected and is hard to repair. JPEG scans follow sequential compression. An image region is compressed with the help of information from the previous region of the image. When one region gets damaged all the other following regions deliver wrong information. Faded lines appear in wrong color.

 

Damage in Header

‘Header’ and ‘Scan’ are two parts of a JPEG file. Header takes only .1 percent of the file data. If the header of JPEG file becomes damaged, repair is very hard to perform. A JPG scan can only be decoded by the information stored in the header. Even a little error in JPEG header makes whole header invalid. If the image files are similar to each other you can use the header of some other image in place of the damaged error to open the photos. Headers of image files should be optimized for the image containing it, but it is not a restriction. Most of the image processors and Cameras don’t optimize headers. Optimization of headers is avoided to increase the speed of JPEG compression. Default standard for headers recommended by JPEG is used for non-optimized headers. This makes the possibility to interchange header of images to fix the damage in header.

 

Thumbnail View of the Corrupt Image Exists

Thumbnail of a JPEG image is saved in its header. As the header only takes about 0.05 percent of the whole file, it is mostly safe from corruption. Thumbnail, or the miniature of an image, is saved in the header of the JPEG file. This thumbnail is shown as preview in applications, browsers, camera without loading and decompressing the whole image. If there is some damage in the scan (body) of the image and if the header of the image is in good condition, then the thumbnail is visible but the image is not able to open. Some applications store more than one thumbnail of a JPEG image in the header.

 

Grey Area in the JPEG Image

When an image is moved from camera to computer or some other USB drive, data corruption can take place. It may also be possible that the whole image is lost for ever. If there is no valid ending of the JPG file, the image may not get opened for viewing.

 

If the above solution does not solve your problem, you can try JPEG Recovery Software.