JPEG Medic // Accurate Manual JPEG Recovery
Table of Contents
  1. Overview
  2. Theory of JPEG Repair
    1. JPEG structure
    2. How to fix broken JPEG file
  3. Working with the Program
    1. Main menu
    2. Virtual folder tree
    3. Files panel
    4. Preview panel
    5. Cluster view
    6. Hex view
  4. Repairing JPEG image
    1. Opening JPEG file
    2. Repair window
      1. Menu commands
    3. Repair procedure
      1. Visual analysis and localization of damaged MCUs
      2. Finding the next correct MCU
      3. Deleting damaged MCUs
      4. Inserting empty MCUs
      5. Color correction
        1. Automatic color correction
        2. Manual color correction
      6. Filling empty MCUs with data
        1. Use the thumbnail image to fill the empty MCUs
        2. Auto-generate missing content
    4. Saving repaired JPEG image
    5. Repairing fragmented JPEG file
    6. Repairing damaged JPEG image based on SOS marker
    7. Repairing JPEG file encoded by ransomware

How to fix broken JPEG file

Fixing a broken JPEG file typically consists of the following steps:

  1. Locate good, non-damaged MCUs
  2. Remove damaged MCUs
  3. Align non-damaged MCUs to correct positions
  4. Apply color correction to MCUs positioned after breaches caused by removal of damaged MCUs
  5. Fill "cavities" in the image caused by removal of damaged MCUs if possible

In theory, one can open a damaged JPEG file in a hex editor and make the corresponding changes manually. But such way of fixing JPEG is way too complex and time-consuming. JpegMedic offers a much more convenient visual semi-automatic way to follow the above repairing procedure.

If the header section of a JPEG file is damaged, it can also be recovered by trying to replace the damaged header with the one from a healthy JPEG image made by the same camera.

Please refer to the Repair JPEG section to learn how to repair damaged JPEG files using JpegMedic.