Reading the IPTC EnvelopeRecord Tags in a jpeg file

Posted on 2009-02-11 12:12:29-08 by frereroy

I am rtrying to work out why accented characters written to IPTC in accented characters is interpreted and misinterpreted according to the programme that reads or writes it and also on Win and Mac. I cannot work out the command line for exiftool to return the field 90 - CodedCharacterSet in the IPTC EnvelopeRecord Tags. Any help would be appreciated.

Direct Responses: 9925 | Write a response

Posted on 2009-02-11 13:53:57-08 by exiftool in response to 9922

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

Did you read FAQ number 10? This may be of some help. Also see FAQ number 18.

The command to extract the CodedCharacterSet is:

exiftool -codedCharacterSet FILE

I suggest using UTF-8 if your applications support it. The command to set this is:

exiftool -codedCharacterSet=utf8

(note: no "-" in "utf8")

I hope this gets you going.

- Phil

Direct Responses: 9926 | Write a response

Posted on 2009-02-11 14:05:45-08 by frereroy in response to 9925

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

Thanks for that. Yes I had read the FAQ 10 and 18 also a thread from last year. After setting utf8 with exiftool (I got an updated file message) looking at it in a Hexeditor my character e9 (e accent) was still e9 I understood that it would be converted to the UTF8 equivalent. Am I missing something?

Direct Responses: 9927 | Write a response

Posted on 2009-02-11 16:11:17-08 by exiftool in response to 9926

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

If you set the IPTC CodedCharacterSet to UTF8, then the characters are passed straight through without translation since exiftool expects input in UTF8. Exiftool also supports input in Windows Latin1, and for this you use the -L option. If you use the -L option and write to IPTC where the CodedCharacterSet is UTF8, then exiftool will translate from Latin1 to UTF8. It sounds like this is what you want.

- Phil

Direct Responses: 9928 | Write a response

Posted on 2009-02-11 16:51:46-08 by frereroy in response to 9927

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

Thanks. My ultimate aim is to have IPTC data written to an image file in utf8.

I have been tried out most of what is out there including the good freebies like Irfanview and Xnview to Photoshop CS4 and AcdSee Pro 2. Only Photoshop and Bridge write in UTF8 but strangely the file is not signed "Exiftool -codedCharacterSet FILE" does not return a value.

I was hoping that I could find a way for Exiftool to rewrite existing Latin1 encoded data to UTF8 and then sign the file as UTF8 - all in batch mode - but I am probably dreaming...

Direct Responses: 9929 | Write a response

Posted on 2009-02-11 17:15:10-08 by exiftool in response to 9928

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

"I was hoping that I could find a way for Exiftool to rewrite existing Latin1 encoded data to UTF8 and then sign the file as UTF8 - all in batch mode - but I am probably dreaming..."

This command will convert Latin1-encoded IPTC to UTF-8 for all files in directory DIR:

exiftool -tagsfromfile @ -iptc:all -codedcharacterset=utf8 DIR

This will rewrite all IPTC in each file, performing the appropriate translations.

But be careful because if the files are already UTF-8 and CodedCharacterSet was not set properly as you mentioned, then the values will be incorrectly translated. ExifTool relies on CodedCharacterSet being set properly when translating extracted values.

- Phil

Direct Responses: 9930 | Write a response

Posted on 2009-02-11 17:39:34-08 by frereroy in response to 9929

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

That works like a treat. Many thanks.

Just for the record I have found an application that writes IPTC in UTF8 AND signs the file as UTF8 and that is Photo Mechanic.

Your solution is great for my photo archives.

BTW, How can I set "Latin1" in the CodedCharacterSet before translating to UTF8- it an escape character, no ?

Direct Responses: 9931 | Write a response

Posted on 2009-02-11 18:58:32-08 by exiftool in response to 9930

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

IPTC is absurd. If I understand the ISO 2022 specification, the only encoding that can be invoked directly via the CodedCharacterSet is UTF-8. Other character character sets can only be designated by CodedCharacterSet, but they must be invoked by escape sequences in the text itself. So the common practice to assume Latin1 (or some other local character set) if CodedCharacterSet is missing. This is what exiftool does.

Direct Responses: 9933 | Write a response

Posted on 2009-02-11 19:11:19-08 by frereroy in response to 9931

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

Absurd is the word! I was working on a Mac and sucessfully encoded my IPTC data from Latin1 to UTF8 and was able to read it correctly in many different graphic applications. Back on the PC Xnview and Irfanview show the double byte characters of the UTF8 and it is only Photoshop that interprets them correctly. I read somewhere else in the forums here that the character set used by many programmes is that of the machine - Western European Windows in my case (Latin1).

Direct Responses: 9935 | Write a response

Posted on 2009-02-11 20:12:31-08 by exiftool in response to 9933

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

Exactly. Many software just uses the local character set. However, UTF8 is becoming a standard, and is being recommended by the MWG, so I think eventually other software will come around to dealing with UTF8 properly in IPTC.

- Phil

Direct Responses: 9937 | Write a response

Posted on 2009-02-12 07:41:22-08 by frereroy in response to 9935

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

That's good news. In the meantime. Is it possible to convert a jpg that has the IPTC and XMP information stored in UTF8 back to Latin1?

I know that -L reads the info but how to rewrite it?

Direct Responses: 9940 | Write a response

Posted on 2009-02-12 11:23:51-08 by exiftool in response to 9937

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

This will do the conversion to Latin1 for a single file, presuming that the CodedCharacterSet is set to utf8 to begin with:

exiftool -tagsfromfile FILE -iptc:all -codedcharacterset= FILE

But due to the different order of operations in batch mode (tags are copied from the file after static tag assignments have been performed), the command is a bit different in batch mode:

exiftool -tagsfromfile @ -iptc:all --codedcharacterset -codedcharacterset= DIR

The bottom line is that exiftool encodes IPTC based on the value of CodedCharacterSet.

- Phil

Direct Responses: 9949 | Write a response

Posted on 2009-02-12 14:08:21-08 by frereroy in response to 9940

Re: Reading the IPTC EnvelopeRecord Tags in a jpeg file

Many thanks Phil - always can count on a good solution from you. Now I can change the metadata charset as necessary in waiting for all applications to be able to read and write in utf8. I remember all this charset business from back in the days of Windows 95 when trying to write and send emails in both Eastern and Western Europe charset. Sometimes it seems as if progress is not that speedy ;)

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