JPG-Repair Toolkit allows you to recover data from corrupted CR2 photos (JPEG). Canon RAW photos (CR2) contain the raw, ‘undeveloped’ sensor data. JPG-Repair Toolkit can process multiple Canon RAW files (Cr2) files in batch.
Commonly Canon RAW photos embed one or more JPEGs: a low resolution thumbnail, a medium resolution preview, and in many cases a full frame preview. I have seen CR2 photos were a full frame JPEG was embedded even though the camera was set to shoot at a lower resolution! Using JPG-Repair Toolkit you can extract the full frame preview.
Technically JPG-Repair Toolkit does not repair CR2 photos, it extracts JPEGs already embedded! Of course having undeveloped and unprocessed RAW data is probably preferable, the full frame JPEG is hardly worthless. If the RAW itself is absolutely necessary, please submit one or two corrupted + an intact CR2 shot with the same camera and settings as I am some times able to repair these manually.
How to recover data from corrupted CR2 photos using JPG-Repair Toolkit
Time needed: 1 minute, assuming you have downloaded JPG-Repair Toolkit.
To determine signatures I examined RAW files taken from: http://www.rawsamples.ch/index.php/en/canon.
And also: https://www.wesaturate.com/.