Streaming H.264 files on Bravia EX series

I already had a PS3 and a Humax HDR, both of which have DLNA capabilities. But when I got a new Sony Bravia KDL-40EX503 TV, I gave it a whirl to see what it would stream and what it wouldn't. Sony's documentation on the topic is predictably sparse, but it did imply support for AVC/H.264 and MPEG2 encoded HD video. I was therefore disappointed to find that only the SD MPEG2 files on my ReadyNAS Duo could be accessed through the Bravia's UI. The H.264 encodes would not show up, now matter what container they were in.

After some reading of the DLNA specifications, experimentation and debugging of the DLNA communication going back and forth to the TV, I established that the issue lay with the supported media types reported by the TV (the DLNA.ORG_PN values, for DLNA geeks). The final piece of the puzzle came via a discussion thread on a similar topic in the forum for the Servio DLNA server. The TV can in fact decode these videos, but chooses to ignore them unless they are advertised by the server with a specific media type. So I took about delving into the source code for the minidlna DLNA server used in the ReadyNAS.

After spending some time familiarising myself with the architecture (and with the C programming language as a whole which I do not use in my day job), I implemented a workaround. The modification causes minidlna to check if the client requesting the list of media files is a Bravia TV, and change the media type for the affected files to ones supported by it. Now the TV shows and plays back my H.264 files (mpg/vob/ts). Win! I submitted the patch so that it can be included in a later version of minidlna.