Error in docs about "file creation date"

[Wilhelm Sanke]

On Fri, 18 May 2007, "J. Landman Gay" <jacque at hyperactivesw.com> wrote:

> Wilhelm Sanke wrote:
>
> >> While trying to add the creation date to the filename in a "thumbs"
> >> application I noticed that the creation date is actually item 5 of the
> >> detailed files rather than item 4, number 4 really containing the
> >> modification date.
> >>
> >> Since the "detailed files" was introduced in Rev version 1.0 and
> >> modified in 1.1 nobody seems to have made use of the creation date 
> over
> >> the last years?
>
>
> On my OS X machine, it's the way the docs say. What OS are you using?
>
>
> -- Jacqueline Landman Gay | jacque at hyperactivesw.com HyperActive 
> Software | http://www.hyperactivesw.com


I observed this while working on a WindowsXP machine, and I have now 
checked what happens on MacOS (still 10.3.9 on my G4 Powerbook).

For the testing I used two JPG-images, both taken on March 4 with a 
digital camera. I modfied one of these images today - May 19 - by 
changing the contrast with PaintshopPro 11 and saving the image under 
the same name. For purposes of comparison, let's call this image "M" for 
modification.
I did not touch or change the second image  in any way, let's call it 
"O" for original.

I copied both images to the Powerbook using an USB stick.

Looking at the EXIF data of the images (with PaintshopPro on Windows) I 
get this information:

Image M:  "date and time" : May 19
                "original date"   : March 4
                "digitalized":      : March 4

Image O:  "date and time" : March 4
                "original date"   : March 4
                "digitalized":      : March 4

Loading the two images into my "thumbs" application and using "the 
detailed files" I get

with item 5 of the detailed files

image M: "May 19", and for image O: "March 4".

With item 4 of the detailed files I get "March 15" for both images, 
which is apparently the date I transferred the images from my camera to 
the computer, a value not contained in the EXIF data.

On my Mac:  The photo information in "iTunes" reads

for image M: "created" ("aufgenommen" in German): March 4
                   "digitalized": March 4
                   "modified"  : March 4
                   "imported" : May 19

for image O: "created"    :March 4
                   "digitalized": March 4
                   "modified"  : March 4
                   "imported" : May 19

Now the corresponding image information in  the "thumbs" stack on the 
Powerbook:

With item 5 of the detailed files I get "May 19" for image M and "March 
4" for image O.

With item 4 of the detailed files I get "Jan 18, 2038" for both 
images!(?); maybe this is an effect of the USB stick? (The date 
information in the systems folder shows correctly the date of today "May 
19".)


Here is the script snippet I use to append the creation date to the 
image name field under the thumb:
   
   "put item 5 of line i of tdetfiles into Datum
    convert Datum from dateitems to long date
    put Tab&item 2 to 3 of Datum after fld Feld"

================================
Summary:

- "modification" and "creation" dates are not exactly corresponding to 
EXIF or iTunes information
- using item 4 of the detailed files which somehow returns a "transfer" 
date is not really useful. It probably only returns a "creation" date 
when an image was created on the computer and not transferred from 
elsewhere.

--
Wilhelm Sanke
<http://www.sanke.org/MetaMedia>