3D and HD

It seems that the Playstation 3 is likely to get its Blu-ray 3D firmware upgrade in September. That the PS3 can be upgraded at all for this purpose is something I find quite interesting.

My understanding is that the preferred signal for Blu-ray 3D is a form of 1080p48. Certainly that is the volume of video data sent: 1080p24 x 2 for the two eyes. It could be that these are conveyed one after the other, which would seem the obvious way, but I suppose there could be reasons for some form of interlacing or other data organisation.

(I’ve just tried plugging the Panasonic Blu-ray 3D player into the Epson EH-TW5500 home theatre projector, because I reckon that projector most likely supports 1080p48 signals, which can be produced by some video processors. But the Panasonic player must have queried the projector, decided it doesn’t support 3D, and simply supplied it with a regular 1080p24 signal from the 3D disc.)

Presumably, then, for the PS3 to support Blu-ray 3D output it must have a chipset capable of delivering data at 1080p48 or something. Or must it? It certainly supports 1080p60 output, so it could convert the output to this. You’d get 3D, but pans would be jerky. So we’ll have to wait and see how it comes out.

Meanwhile, I was trying to find some worthwhile upcoming HDTV to give the Panasonic Blu-ray recorder a workout. Golly, it’s hard to find out these days. Prime doesn’t seem interested in indicating which of its programs are in HD, and neither does WIN. It turns out that there are a couple of movies on Saturday night on Prime, so I’ll record them to see how it goes. I can always, I supposed, record ‘Ultimate Fighting’ from OneHD. Ho hum.

Update (1:31pm): Simon in comments below wonders whether the HDMI 1.3a output of the PS3 allows for 3D. Actually, it doesn’t. HDMI 1.4 does. But that’s only the spec. The HDMI organisation goes to great lengths to say that even if some device has HDMI 1.x compliance, that doesn’t necessarily mean it implements all the features.

The most obvious example of this is … the PS3. Even though rated at HDMI 1.3 right from the start, until the PS3 Slim came out, it could not deliver the new HD audio standards as bitstreams. This was a hardware issue to do with its chipset. The new firmware supports bitstream of Dolby TrueHD and DTS-HD MA, but only on the PS3 Slim. If you set an older model to ‘bitstream’ output, you get either the DTS core or the embedded Dolby Digital as appropriate.

A post on hidefdigest suggests that all Blu-ray players will support Blu-ray 3D, but only at 1080i. It claims this is because ‘for a 3D picture, two images have to be shown nearly simultaneously. Since HDMI 1.3 can’t handle two 1080p pictures at that speed, you’ll get two 1080i pictures.’

That’s plainly wrong. HDMI 1.3 can handle two 1080p pictures easily. 1080p24-3D or 1080p48 requires only 80% of the bandwidth of 1080p60. The problem would be whether the video chips are versatile enough to cope with 48fps in addition to the more common 24fps, 50fps and 60fps. Just because a chip can output a higher speed doesn’t mean that it can deal with a lower, non-standard speed. There are lots of TVs that are perfectly happy with 1080p60, but won’t touch 1080p24, even though it demands only 40% of the other signal’s capacity.

Anyway, it appears that the PS3’s video output is sufficiently versatile to produce some form of 3D output. And, once again, we’ll see what it is when it finally arrives. But 1080i makes no sense at all.