Menu images does not show in hardware player but does in software players and PS3

Question

I'm developing a blu-ray menu with java (BD-J). I developed a simple loading animation. when running it on PS3, soft players (PowerDVD, TotalMedia Theatre, ...) and some hard players (Samsung ht-c6950w), there is no problem and it runs like a charm. But when running it on other hard players (LG, Panasonic, Samsung,...) nothing happens. You cannot see any image on the screen.

Answer 1

BD-J Xlets is JavaME.

The thing about JavaME (on both Blu-ray players and cellphones) is that it behaves differently on different devices. Different manufacturers simply implements it differently. (Hence why Java coders replaced the "Code once, run anywhere" with "Code once, debug everywhere").

Some Blu-ray players are very forgiving while others are very tricky.

So yes, you will need to debug on a lot of different players to make sure your Xlet runs on as many different devices as possible. (I think I have about 15 different players, bought on various flee markets and such).

Here are two things I've learned during my own research:

• Some players require a video to be played before the BD-J works. So if you don't have any video in your project, then add a little 3-second long black screen and play it.
• There's a folder called CERTIFICATE in the root of the disc. This folder needs to contain a file id.bdmv containing the ID of the disc - regardless of your BD-J Xlet is signed or not. Again; some players are forgiving about this - others aren't.

There aren't many places left for those interested in BD-J, but you can find some useful links at http://www.Blu-Play.com