[tracker] IPTC extractors : use nco:contributor for contact metadata

[Carlos Garnacho <carlosg src gnome org>]

commit a05758cddec975f4b24b9268226f1aaf3c2bc1ac
Author: Julien Hémono <whackvault me com>
Date:   Wed Mar 9 20:11:42 2016 +0100

    IPTC extractors : use nco:contributor for contact metadata
    
    5a27279a7e07a9f1f0c58f663f4c290c397d4aff adds support for contact
    IPTC metadata and represents it with a nco:representative predicate.
    
    This contradicts the ontology that stipulates that the subject of
    a nco:representative predicate is a nco:Contact. Consequently, updates
    from extraction of files containing this IPTC field are rejected by
    the store.
    
    This fix uses the nco:contributor predicate instead. Official
    documentation at [1] says the field "Identifies the person or
    organisation which can provide further background information on
    the objectdata." Nco:contributor is therefore too narrow as not every
    such person need be a contributor. The adequate predicate doesn't
    exist but if it did it would definitely at least be a nao:annotation
    or more narrowly a nao:isRelated. But I deem these too broad because
    their range isn't a person or an organisation.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=762675

 src/tracker-extract/tracker-extract-jpeg.c |    2 +-
 src/tracker-extract/tracker-extract-tiff.c |    2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/tracker-extract/tracker-extract-jpeg.c b/src/tracker-extract/tracker-extract-jpeg.c
index 8097a7b..a9f8f6e 100644
--- a/src/tracker-extract/tracker-extract-jpeg.c
+++ b/src/tracker-extract/tracker-extract-jpeg.c
@@ -338,7 +338,7 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
                }
                tracker_sparql_builder_insert_close (preupdate);
 
-               tracker_sparql_builder_predicate (metadata, "nco:representative");
+               tracker_sparql_builder_predicate (metadata, "nco:contributor");
                tracker_sparql_builder_object_iri (metadata, uri);
                g_free (uri);
        }
diff --git a/src/tracker-extract/tracker-extract-tiff.c b/src/tracker-extract/tracker-extract-tiff.c
index d14ac79..d1c6d50 100644
--- a/src/tracker-extract/tracker-extract-tiff.c
+++ b/src/tracker-extract/tracker-extract-tiff.c
@@ -606,7 +606,7 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
                }
                tracker_sparql_builder_insert_close (preupdate);
 
-               tracker_sparql_builder_predicate (metadata, "nco:representative");
+               tracker_sparql_builder_predicate (metadata, "nco:contributor");
                tracker_sparql_builder_object_iri (metadata, uri);
                g_free (uri);
        }