Canon EOS-1D X Instruction Manual page 36

Batch Transfer
[RAW+JPEG transfer] Options
Menu Operation During Image Transfer
You can use the menu even during image transfer. However, to prevent
transfer problems, some menu items are unavailable during transfer,
such as [Communication settings], [Protect images], [Erase
images], [Format card], and [Record func+card/folder sel.].
If you shoot a movie during the image transfer of captured images, the
image transfer will be temporary cancelled during movie shooting.
Batch Transfer of Images in a Folder
36
Selecting [RAW+JPEG transfer] in step
2 on page 34 will give you the option of
transferring RAW images, JPEG images,
or both types of images.
The options will be the same whether
you specify [Sel. Image], [Sel. n], or
[All image] as the image selection
method.
On the [32] tab, select [Image
1
transfer].
Select [Image sel./transfer].
2