A few years back we saw some PS4 BD-J Homebrew ports followed more recently by PS4 Webkit Emulators, a BDLive Bug and a PS4 JavaScript Emulator demonstration video with some answers to common questions recently by musician and coder Mr_lou. 
To quote: Hello all. Just signed up here, and thought I'd introduce myself (in this thread because BD-J dev is the main reason I signed up, and I don't actually own any PlayStations).
Been working on a BD-J project for 5 years now. Info at www.8bitmemoirs.com
Got the HDCookBook for my birthday, and have studied BD-J a lot. Very little info online about it indeed. Some Japaneese sites are rather good, but requires Google Translate.
Is anyone here still interested in BD-J? I think I can answer a few questions from this thread (although it's old), so here goes:
From Lucif3r: Would make more sense if the PS4 supported such a thing from a USB stick or similar... Wasting a blueray disc for a java app? No ty... o.o
Yea, Sony blocked the possibility of booting a Blu-ray Disc from USB, as we all know. But I believe it's still possible to run BD-J stuff from a USB - if you boot from a disc.
So yea, you will still need to burn a disc - but you can settle for having this one disc for booting, and then run whatever Xlets you have on your USB.
I admit I haven't tried this myself yet (because I'm using a Dune HD Smart D1 for testing which lets me run my stuff from harddisk), but from what I've read in HDCookBook it should be possible, because:
And of course, while developing, you can use a software player like PowerDVD from Cyberlink. (Other software media-players are also getting BD-J support these days, like VLC and Kodi).
From FreePlay: There's no audio. But I think we already knew that.
I don't think this is because you can't have audio with BD-J. I think it's more a question of the developers didn't bother to port the audio-system to a BD-J compatible one.
From what I've read, the whole Java Media Framework (JMF) should be available in BD-J. I admit I don't have any experience with JMF myself, but a quick look at the docs tells me that it supports playback of Linear PCM WAV, which as far as know, is a RAW format.
The dynamic audio generators usually uses raw format (I think), so it should "just" be a matter of finding a way to feed dynamically generated audio into JMF.
Not claiming this is possible. Just saying I think it can be done, somehow. I'm a musician, and a coder, but I have never experimented with dynamic audio generation yet. But this whole dynamic audio generation is only interesting for emulators.
When we're talking homebrew games, you can always add audio in the form of video-playback. This is what I'm doing in my own project. Plenty of audio there.
From FreePlay: Something else I forgot to mention that you might have noticed in the video: emulators run REALLY FAST on this. Like, around 400% speed. I don't know why.
Without having tried the NES emulator, my guess is that it was created for PS3 with a "dumb" timing setting, which is the easiest way of doing it. The PS4 obviously having a faster CPU will result in a faster execution.
I suppose you could say that the emulator should just have been coded slightly differently.
From incognita: May be you can't hack the PS4 but I think you can do a lot of interesting hombrews.
Absolutely I think so too. My project "8-bit Memoirs" has been a very interesting one so far. Learning a lot of what's possible.
I admit I'm not as much focused on the PS3 as such, but rather Blu-ray Players in genereal (which is why my project has been tested on A LOT of different players).
If you only target PS3, you'll have it easy. Because getting stuff to run on all players requires a lot of patience and work. Blu-ray Players are just as different and buggy as JavaME enabled cellphones.
I would like to add the following. Some people say that Blu-ray Disc Java (BD-J) obviously isn't as powerful as native coding on the PlayStation - and they're of course absolutely right.
You shouldn't expect to be able to code full-blown 3D shooters. BD-J was created for simple menu stuff for Blu-ray movies.
That being said, you shouldn't underestimate what you can do with BD-J either. Take a look at this BD-J demo for example:
Finally, from GregoryRasputin comes the following summary and related BD-J files:
Download: Blu Ray Java
Here are some facts:
To quote: Hello all. Just signed up here, and thought I'd introduce myself (in this thread because BD-J dev is the main reason I signed up, and I don't actually own any PlayStations).
Been working on a BD-J project for 5 years now. Info at www.8bitmemoirs.com
Got the HDCookBook for my birthday, and have studied BD-J a lot. Very little info online about it indeed. Some Japaneese sites are rather good, but requires Google Translate.
Is anyone here still interested in BD-J? I think I can answer a few questions from this thread (although it's old), so here goes:
From Lucif3r: Would make more sense if the PS4 supported such a thing from a USB stick or similar... Wasting a blueray disc for a java app? No ty... o.o
Yea, Sony blocked the possibility of booting a Blu-ray Disc from USB, as we all know. But I believe it's still possible to run BD-J stuff from a USB - if you boot from a disc.
So yea, you will still need to burn a disc - but you can settle for having this one disc for booting, and then run whatever Xlets you have on your USB.
I admit I haven't tried this myself yet (because I'm using a Dune HD Smart D1 for testing which lets me run my stuff from harddisk), but from what I've read in HDCookBook it should be possible, because:
- Xlets can start other Xlets
- The disc filesystem gets merged with the USB filesystem (for BD-Live).
And of course, while developing, you can use a software player like PowerDVD from Cyberlink. (Other software media-players are also getting BD-J support these days, like VLC and Kodi).
From FreePlay: There's no audio. But I think we already knew that.
I don't think this is because you can't have audio with BD-J. I think it's more a question of the developers didn't bother to port the audio-system to a BD-J compatible one.
From what I've read, the whole Java Media Framework (JMF) should be available in BD-J. I admit I don't have any experience with JMF myself, but a quick look at the docs tells me that it supports playback of Linear PCM WAV, which as far as know, is a RAW format.
The dynamic audio generators usually uses raw format (I think), so it should "just" be a matter of finding a way to feed dynamically generated audio into JMF.
Not claiming this is possible. Just saying I think it can be done, somehow. I'm a musician, and a coder, but I have never experimented with dynamic audio generation yet. But this whole dynamic audio generation is only interesting for emulators.
When we're talking homebrew games, you can always add audio in the form of video-playback. This is what I'm doing in my own project. Plenty of audio there.
From FreePlay: Something else I forgot to mention that you might have noticed in the video: emulators run REALLY FAST on this. Like, around 400% speed. I don't know why.
Without having tried the NES emulator, my guess is that it was created for PS3 with a "dumb" timing setting, which is the easiest way of doing it. The PS4 obviously having a faster CPU will result in a faster execution.
I suppose you could say that the emulator should just have been coded slightly differently.
From incognita: May be you can't hack the PS4 but I think you can do a lot of interesting hombrews.
Absolutely I think so too. My project "8-bit Memoirs" has been a very interesting one so far. Learning a lot of what's possible.
I admit I'm not as much focused on the PS3 as such, but rather Blu-ray Players in genereal (which is why my project has been tested on A LOT of different players).
If you only target PS3, you'll have it easy. Because getting stuff to run on all players requires a lot of patience and work. Blu-ray Players are just as different and buggy as JavaME enabled cellphones.
I would like to add the following. Some people say that Blu-ray Disc Java (BD-J) obviously isn't as powerful as native coding on the PlayStation - and they're of course absolutely right.
You shouldn't expect to be able to code full-blown 3D shooters. BD-J was created for simple menu stuff for Blu-ray movies.
That being said, you shouldn't underestimate what you can do with BD-J either. Take a look at this BD-J demo for example:
Finally, from GregoryRasputin comes the following summary and related BD-J files:
Download: Blu Ray Java
Here are some facts:
- This is NOT a hack.
- This is NOT anything major and will not lead to anything major.
- This will NOT let you run PS4 “backups”.
- This will NOT give you any access to the PS4’s OS system files.
- This is NOT illegal.
- This does NOT void your warranty.
- This will NOT let you run PC games on your PS4.
- This will ONLY let you run Java software.
- This WILL give you Homebrew.
- This IS totally doable.
