Canon EOS Rebel T4i 18-135mm IS STM Lens Kit Instruction Manual page 245

The total number of images with a given rating that can be displayed is 999.
If there are more than 999 images with a given rating, [###] will be displayed
for that rating.
Taking Advantage of Ratings
With [x2: Image jump w/6], you can display only images and
movies with a specific rating.
With [x2: Slide show], you can play back only images and movies with
a specific rating.
With Digital Photo Professional (provided software, p.350), you can
select only images and movies with a specific rating (still photos only).
With Windows 7 and Windows Vista, you can see each file's rating as
part of the file information display or in the provided image viewer (still
photos only).
3 Setting Ratings
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