validate - question of understanding

[herb]

Hello Phil,

thanks for the new feature -validate.
But for all my images taken with an Olympus camera E-PL6 I get the following output for command:
exiftool.exe -all:all -validate validate.jpg

Code Select Expand

---- ExifTool ----
ExifTool Version Number         : 10.41
Warning                         : [minor] Odd offset for ExifIFD tag 0x9003
Warning                         : [minor] Odd offset for ExifIFD tag 0x9004
Validate                        : 2 Warnings (all minor)
Validate                        : 2 Warnings (all minor)
< all other tags removed>

Can you please give a short explanation, why the offset of tags DateTimeOriginal and CreateDate is "odd".
I have attached a htmldump of such a file.

And by the way, why is the info "Validate: 2 Warnings (all minor)" given twice?

Best regards
Herb

[Phil Harvey]

Hi Herb,

The TIFF/EXIF specification states that all values should be on even-byte boundaries so ExifTool warns about ones that are on odd-byte boundaries.  You can see this best in the -htmldump output.

The Validate tag is reported twice because you requested it twice: once with -all:all and a second time with -validate.  Hmmm.  This makes it difficult to include the Validate tag in the rest of the output.  I was thinking of it as more of a stand-alone feature.  I'll have to think about this.

- Phil

Edit: OK.  I'll enhance the API Validate option so that the following command may be used with ExifTool 10.42 to extract all tags including the Validate tag:

exiftool -api validate=2 FILE

Also, I notice that it wasn't validating the JPEG image data as I had intended, so this will be fixed in 10.42 as well.

[herb]

Hello Phil,

thanks for your fast reply.
That the values should be on even-byte bounderies was new to me.

Best regards
Herb

[herb]

Hello Phil,

please allow another comment to "exiftool -api validate=2 FILE".

Exiftool 10.41 does the following
- exiftool -validate FILE:            gives only result of validation
- exiftool -all:all FILE                  gives all tags, but no result of validation
- exiftool -all:all -validate FILE   gives all tags and also result of validation (but why twice?)

It is now unclear to me what -api validate=2 is good for?

Best regards
Herb

[Phil Harvey]

Hi Herb,

Actually, I changed my mind about -api validate=2 because you can already do this now with -api requesttags=validate.

Your command gives Validate twice for the same reason that this command gives FileName twice:

exiftool -all:all -filename FILE

The only difference is that the Validate tag isn't normally generated, so if you just specify -all:all it doesn't appear.  But once it is generated, it is included with all of the tags.

- Phil

[herb]

Hello Phil,

thanks for your explanations and for the hint -api requesttags=validate.

I worked with it and I have seen that for files - with no IPTC tags - the command
exiftool -iptc:all -api requesttags=validate FILE
gives the validate output to stderr (not on stdout) and adds the name of the file.

I this case it would be fine to have the result for valiadte only on stdout without addition of filename.

Best regards
Herb

[Phil Harvey]

Hi Herb,

You are confused again.  You won't see the Validate tag if you ask only for -iptc:all.

- Phil

[herb]

Hello Phil,

Yes you are right, I am confused now. I see only the warning.

Thanks and Best regards
Herb