I wrote a little bit about this feature in a bug report. I've pasted it here since it may help once you start working with that feature.
To answer your question, yes. TWG will put the chosen IPTC text below the photo (see below for a little about choosing..). I observe a slight quirk though in getting it to display. I must advance forward 2 photos before the text begins to show -- or advance/rewind in the case of just two images in the album. I am not sure that you could get it to display with only one image in an album with this bug.
This last thing really doesn't seem like a bug but how-to 38 describes defaults that I assume should work with Xnview, however config.php with:
Code:
$iptc_fields_for_caption= array("2#105","2#005");
..doesn't retrieve the "Caption" data added using Xnview 1.91 -- I don't know what it actually will retrieve -- will test by adding all IPTC data and see what get's extracted.
What I needed to do in order to get the "Caption" data per Xnview writing was to change in the my_config.php:
Code:
$iptc_fields_for_caption= array("2#120");
..so it uses the TWG "Description" data. A little confusing since there isn't a description entry for IPTC with Xnview.
FWIW the IPTC "Keywords" written with Xnview are mapped perfectly to the TWG "Tags" though..
I really have not yet researched the IPTC so I don't quite follow the n#nnn offset stuff yet or the mapping and what is TWG specific and what is IPTC specific.
I also have Photoshop so I may fiddle around with writing IPTC data with it to see if it's any different.
Again, no big deal and not really a bug, remapping is easy enough.. The how-to 38 though does kind of read like the default TWG should handle the Xnview IPTC "Caption" -> TWG "Caption" which it doesn't, confusing things somewhat.
##UPDATED##Just wanted to pass along the mapping if IPTC data that I have observed (using the "Info" menu command) after populating all fields with both PS and Xnview. The left side below shows the TWG field name and the right is the corresponding IPTC data -- described related to the IPTC writing menu(s) of the corresponding program used.
The mapping is more clear now to me. The default config.php setting for $iptc_fields_for_caption is specifically for display purpose, showing the field choosen under the photo/in lightbox.. It's not actually changing which TWG field the IPTC data imported gets mapped to AFAIK.
EG: with the default config.php the TWG Info that is used under photos would be "Caption" which is actually the "Caption Headline" IPTC data. The mod to my_config.php above simply tells TWG to show the TWG Info "Description" which is the IPTC caption 'data' field.
Code:
File name = pshop_test.jpg
Date = 9.6.2007
Size = 127 KB
Resolution = 640 x 480
Image tags = Keyword1
Album tags = Categories - Supplemental Catego
Description = General - Caption
Autor = General - Caption Writer
Copyright = Genral - Copyright Notice
Source = Origin - Source
Caption = Origin - Headline
----------------------------------------------------------------
File name = xnview_test.jpg
Date = 9.6.2007
Size = 117 KB
Resolution = 640 x 480
Image tags = keyword1
Album tags = Categories - Supplemental Catego
Description = This is caption data
Autor = this is caption author
Copyright = credits copyright
Source = credits source
Caption = this is caption headline