pyexiv2-developers team mailing list archive

[Olivier Tilloy <olivier@xxxxxxxxxx>]

On 2012-01-05, Benjamin Henne <henne@xxxxxxxxxxxxxxxxxxxxx> wrote:
> Hi pyexiv2-developers,
> 
> I currently struggle with pyexiv2 and some complex XMP structures. It is
> currently possible to write such XMP using pyexiv2? I work on extending
> exiv2 with two new namespaces which contain the needed XMP entries. I
> added the first to exiv2, it works using their CLI, but I cannot write
> it using pyexiv2. Can you please help me answering the question if it
> may be on pyexiv2's side or if the other (exiv2) side may not be complete.
> 
> I want to write a xmp struture like the following to file.
> How can I do this using pyexiv2?
> 
>   <MP:RegionInfo rdf:parseType="Resource">
>     <MPRI:Regions>
>      <rdf:Bag>
>       <rdf:li
>        MPReg:Rectangle="0.661608, 0.244310, 0.130501, 0.261002"
>        MPReg:PersonDisplayName="Baby Tux"/>
>       <rdf:li
>        MPReg:Rectangle="0.205615, 0.226100, 0.130501, 0.261002"
>        MPReg:PersonDisplayName="Baby Gnu"/>
>      </rdf:Bag>
>     </MPRI:Regions>
>    </MP:RegionInfo>
> 
> More on the extension of exiv2, the working CLI example and the not
> working pyexiv2 code can be found at
> http://dev.exiv2.org/boards/3/topics/1039#message-1043

Hi Benjamin,

I read the thread on exiv2’s forums, and I saw that you did a thorough
investigation of the problem.

As you already found out, a current limitation of pyexiv2 is that it
doesn’t allow setting the type of an unknown tag in a custom namespace
to anything other than XmpText (this is documented in the tutorial, see
http://tilloy.net/dev/pyexiv2/tutorial.html#reading-and-writing-xmp-tags).

Please keep the list posted on your findings/progress, and don’t
hesitate to ask here if you encounter issues in pyexiv2 itself while
adding those namespaces to libexiv2.

Cheers,

Olivier