Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 474)

Converting HEIF to JPEG
You can convert HEIF images captured in HDR shooting and save them as JPEG images.
Converted JPEGs resemble how the original HEIF image appears on an HDR display
device.
1.
Select [ : HEIF→JPEG conversion].
2.
Select an image.
Turn the < > dial to select an HEIF image to convert to JPEG.
Press < > to convert to JPEG.
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