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dcraw: name swap?

Dave,

> dcraw dscn0055.RAW
Failed to read metadata from 0055dscn.JPG

I executed the above command, then I got the "Failed to read" message right below it. I know my rename of the file caused this message. But the name "0055dscn.JPG" was what I expected. Seems the "dscn" and "0055" are swapped. Is that normal? Is that what Nikon embedded in the raw file?

Chieh Cheng
Wed, 22 Mar 2006 13:42:02 -0800

Hi Cheng,

Nothing is embedded in the raw file. It's just an array of pixels. Dcraw recognizes the file by its size, exactly 2465792 bytes.

See the parse_external_jpeg() function. If the name of the raw photo ends in ".jpg", add one to the image count to find the JPEG photo.

If the name does not end in ".jpg", swap the two halves of the name and change the extension to ".jpg".

The first rule is for Nikon cameras and the second is for Casio and Pentax cameras. Your file renaming caused dcraw to apply the wrong rule. Here are some examples from my collection:

		Raw photo	JPEG photo
Nikon:		dscn3508.jpg	dscn3509.jpg
Nikon:		dscn4477.jpg	dscn4478.jpg
Casio:		0424cimg.raw	cimg0424.jpg
Pentax:		0016imgp.raw	imgp0016.jpg

Dave Coffin
Wed, 22 Mar 2006 17:31:31 -0800

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