Canon EOS 7D Instruction Manual page 180

L Erasing Images
3 Erasing All Images in a Folder or Card
You can erase all the images in a folder or card at one time. When the
[3 Erase images] menu is set to [All images in folder] or [All images
on card], all the images in the folder or card will be erased.
To also erase protected images, format the card (p.43).
180
Select [Select and erase images].
2
Turn the <5> dial to select [Select
and erase images], then press
<0>.
The image will be displayed.
To display the three-image view,
press the <I> button. To return
to the single-image display, press the
<u> button.
Select the images to be erased.
3
Turn the <5> dial to select the
image to be erased, then press
<0>.
The <X> icon will be displayed on
the upper left.
To erase other images, repeat step 3.
Erase the image.
4
Press the <L> button.
Turn the <5> dial to select [OK],
then press <0>.
The selected images will be erased.