Invisible file after WLPG and Picasa change metadata

[cowboy]

Hello. I've created, somehow, an invisible file. Well, at least invisible to Windows XPS3. I've a .jpg file that I used first Window Live Photo Gallery on, and then later Picasa. Think I wrote tags/captions with both programs. (sorry..!) And, Picasa, being last,  changed the software tag, of course. However, at that point, the file becomes invisible to the operating system. There is no thumbnail preview, just a tile, and if you hover over it, the dimensions read "0x0". The only way out of the problem seems to be either stripping the file entirely of metadata, at which point it becomes visible to the system again. I've tried using ExiftoolGui to selectively strip out bit by bit the EXIF, the IPTC, and XMP. Nothing seems to work but a complete strip.  I've tried rotating and resaving, I've tried Geosetter, where someone on a forum had success with a similar file (by changing the star rating, and then rewriting), but no luck there. I can also run the following command on a file "-all= --exif:all", again through ExiftoolGUI, and that seems to help, and leave some of the metadata.  Picasa and WLPG, and their respective proprietors, are, of course, without a clue.

Anway, can someone tell me what, perhaps, happened to the file? Was the EXIF damaged? Was it the IPTC? (I've also had luck with these files in Irfanview, by stripping out the IPTC, which seems odd) Is the command above the best to use to save these files, and at least some of the metadata?

thanks so much,

cowboy.

[Phil Harvey]

I haven't seen this problem before, but Picasa is the most buggy software on the planet when it comes to writing metadata.

If it is the metadata, try writing any EXIF tag using ExifTool (EXIF:Artist is a good one).  If this succeeds, then the new EXIF will be OK.  If it doesn't, consult FAQ 20 for repairing corrupted EXIF.

Also, make sure the file name is valid (ie. doesn't start with a ".").  This can confuse Windows too.

- Phil

[cowboy]

Hi Phil, and thank you. While the write:artist didn't seem to work, the first command in FAQ 20, the delete-and-rebuild command, delivered through the "Exifdirect" in ExiftoolGui, did the trick. Still wonder why it happens, though. There are warnings, an invalid "CanonCameraSettings", a "CanonShotInfo", a "MyColors", and a invalid "FaceDetect1". That last, even though I specifically told Picasa not to scan my photos for Face Recognition. Grrrr.

WLPG seems a little more compliant than Picasa, or at least, I don't see quite the number of warnings in Exiftool after using it. It seems to be Picasa that is writing the damage through to the file, after it has been acted on (rated, captioned, etc) by WLPG.  Also, the file name is valid, per windows. Another odd thing - the files can be seen inside WLPG, or Picasa, or XNview, or Irfanview, or Geosetter. But Windows XP can't display them, and ExiftoolGui also can not preview them.

Phil, would you care to see one of the files in question? I'd be interested in your opinion about what is happening with them. Might be a good addition to your menagerie, and might help someone else in the future. I could email it over if you'd like.

thanks so much...cowboy.

[Phil Harvey]

Sure, send the image to philharvey66 at gmail.com -- I'd be interested to take a look.

- Phil

[Phil Harvey]

I got the sample, thanks.

Very odd.  The only thing I can see wrong with this is that the Canon maker notes have been corrupted.  Do you have a Canon-specific driver installed?  I could see the Canon software getting confused by this, but I would be surprised if Windows cared about it.

Also, did you try just stripping the maker notes -makernotes= instead of all metadata to see if this fixes the problem?

- Phil

Edit: I just happened to have an XP machine handy (a rarity), so I tried this myself.  The problem is a zero-byte APP13 segment that is confusing Windows.  The only way to delete this segment with ExifTool is to rebuild the full metadata as per FAQ 20.

This is a new one for me, but I wouldn't put it past Picasa to write garbage like this.  I spend a lot of time debugging Picasa problems, and it is beginning to get annoying.  Also, I am not surprised if Microsoft software isn't robust enough to handle a zero-byte segment -- their software is still very immature when it comes to handling metadata.  So the problem is caused by questionable metadata practices (Picasa) combined with fragile software (Windows).

[cowboy]

I just happened to have an XP machine handy (a rarity), so I tried this myself.  The problem is a zero-byte APP13 segment that is confusing Windows.  The only way to delete this segment with ExifTool is to rebuild the full metadata as per FAQ 20.

This is a new one for me, but I wouldn't put it past Picasa to write garbage like this.  I spend a lot of time debugging Picasa problems, and it is beginning to get annoying.  Also, I am not surprised if Microsoft software isn't robust enough to handle a zero-byte segment -- their software is still very immature when it comes to handling metadata.  So the problem is caused by questionable metadata practices (Picasa) combined with fragile software (Windows).

Phil, thank you for taking the time to work the problem out with this file. It's worrisome when it occurs; as it appears the file has been damaged in some way. And, neither Msoft or the Picasa folks seem able or willing to assist. And yes, FAQ 20 seems to be the way to go to restore the file, merely deleting the makernotes does not seem to work. One can completely strip all metadata, and that works as well, but one also loses all the info in the file.

As a test, per your statement about Picasa, and Windows, I fired up my favorite Linux distro, and looked at the file. And of course, the thumbnailer viewer there had no difficulty in viewing the file. It's remarkable to me that using two of the more popular photo management tools on Windows XP could render a file "unviewable".  The lesson is - go Linux, and go Exiftool! Again, thank you for taking the time to work through this, and a double thank you for creating and maintaining ExifTool.