Re: Adding new metadata

[Lionel Landwerlin <lionel g landwerlin linux intel com>]

On Fri, 2011-03-11 at 14:01 +0100, Juan A. Suárez Romero wrote:
> On Thu, 2011-03-10 at 18:15 +0000, Lionel Landwerlin wrote:
> > Hi all,
> > 
> > I would like to add some new metadata key mostly to handle some EXIF
> > property available on pictures. Here is the list of what I would like to
> > support :
> > 	   - camera model
> >            - original resolution
> >            - date taken
> >            - orientation
> >            - flash usage
> >            - exposure time
> >            - original size (XResolution/YResolution)
> > 
> > Some of these properties are quite specific. How would you like to see
> > them appear in Grilo ? :
> > 	- exposed in the core as well as already available properties ?
> > 	- private to one plugin ?
> > 
> 
> Being EXIF properties, and thus a standard, I would add them to core. I
> don't see them specific to a plugin, but useful for any plugin that can
> return photos (like Flickr).
> 

In the end, do we want a particular prefix for these keys ?

> 
> > In the second case, how should the corresponding value be retrieved ?
> > Calling grl_media_source_metadata () with keys parameter being NULL ?
> > 
> 
> If you know the key name (let's say "camera-model"), you can ask the
> register for the key, and then use it in source_metadata() function.
> 
> GrlKeyID camera_model = grl_plugin_registry_lookup_metadata_key
> (registry, "camera-model");
> 
> GList *ask_keys = grl_metadata_key_list_new (GRL_METADATA_KEY_TITLE,
> GRL_METADATA_KEY_AUTHOR, camera_model, NULL);
> 
> metadata_key(source, ..., ask_keys, ...);
> 
> 
> 	J.A.