I need help for a *.rw2 image

[herb]

Hello Phil,

It is in discussion to buy a Panasonic Lumix DMC-GH3 camera. To get a better first impression I downloaded some sample images from the internet; e.g.: http://img.photographyblog.com/reviews/panasonic_lumix_dmc_gh3/sample_images/panasonic_lumix_dmc_gh3_12.rw2.

For this image the command "exiftool -all:all <image>" works fine.
But the command "exiftool -all:all -use MWG <image>" throws the warning: "Ignored non-standard EXIF at TIFF-IFD0-JPEG-APP1-IFD0" and not all tags are displayed.

Now I am a little bit confused and need your help.
Thanks for your comments in advance
Herb

[Phil Harvey]

Hi Herb,

Interesting.  We're in a bit of a grey area here.  I would suggest not using the MWG option with RW2 images because the metadata for these images is stored in an embedded JPEG instead of in the file's TIFF structure.  The MWG specifies a standard location for metadata in TIFF-format images, and invoking the MWG option causes other metadata in non-standard locations to be ignored.

- Phil

[herb]

Hello Phil,

thanks for your quick reply and thanks for your investigations.
But please allow some comments and further questions:

The -m option to ignore warnings does not help to display all metadata in case of -use MWG is used.

I also did some tests writing MWG-tags into this image and I have seen no problems.
I wrote tag -MWG:City and it was stored properly.
I also wrote -MWG:ModifyData (which touches also EXIF metadata) and it was also stored properly.
Of course I did not check the file with a HEX-Editor to see the internal structure, I only wrote and read the metadata with Exiftool 9.32.

Is this a surprising result for you?
So is there any chance to display all metadata and to get a warning?

Thanks in advance
Herb

[Phil Harvey]

The -m option to ignore warnings does not help to display all metadata in case of -use MWG is used.

Correct.  Because this is not a minor warning.

I also did some tests writing MWG-tags into this image and I have seen no problems.
I wrote tag -MWG:City and it was stored properly.
I also wrote -MWG:ModifyData (which touches also EXIF metadata) and it was also stored properly.
Of course I did not check the file with a HEX-Editor to see the internal structure, I only wrote and read the metadata with Exiftool 9.32.

Is this a surprising result for you?
So is there any chance to display all metadata and to get a warning?

Does the MWG tags documentation answer these questions?:

Loading the MWG module activates "strict MWG conformance mode", which has the effect of causing EXIF, IPTC and XMP in non-standard locations to be ignored when reading, as per the MWG recommendations. Instead, a "Warning" tag is generated when non-standard metadata is encountered. This feature may be disabled by setting $Image::ExifTool::MWG::strict = 0 in the ExifTool config file (or from your Perl script when using the API). Note that the behaviour when writing is not changed: ExifTool always creates new records only in the standard location, but writes new tags to any EXIF/IPTC/XMP records that exist.

- Phil

[herb]

Hello Phil,

thanks again for your help and shame on me, that I did not recognize these hints in your documentation.

Best regards
Herb

[Phil Harvey]

Hi Herb,

The documentation is often more reliable than my memory.  In this case, I had forgotten about the config option to disable the strict mode, but this could be useful to you.

- Phil