I was asked recently how many phones were HD-capable, and realised that the question is actually quite complex.

I should start with a definition for what I believe constitutes HD, as many handsets already claim some sort of High Defintion credentials, but very few actually deliver it...

- True HD, 1080p, is a 16:9 ratio screen with a resolution of 1920x1080 pixels and a frame rate of 60 frames per second (or 24 fps for Blu-ray players);

- 1080i is the same resolution, but the image is interlaced, effectively halving the frame rate;

- 720p is also 16:9, but with a resolution of 1280x720 pixels.

The highest resolution display on a handset at present is WVGA (800x480 pixels) and there are just under 200 handsets with that spec, the biggest being the HTC HD2 which has a very nice 4.3 inch screen, but WVGA is nowhere near big enough to be classed as HD.My take on HD is that we will see it on phones in certain functions: a)       Capture? Yes: The Samsung i8910 HD (also known (incorrectly) as the Omnia HD) was the first phone capable of capturing 720p HD video and the quality is immense. I think we will see many more phones in the near future being capable of capturing 720p or even 1080p HD;

b)      Playback on screen? No: The Samsung i8910 HD has a very impressive 3.7 inch, 640x360 pixel OLED screen which gives a fantastic representation of high quality (if not HD) video, but it’s not true HD playback on the screen. In fact it’s only nHD (ninth full 1080 HD) at 640x360 pixels. Converting the Samsung i8910’s specs into dots per inch gives a figure of 198dpi.  I would argue that the highest definition screen we will ever see on a phone is QHD (960 x 540 pixels) or at a real push 720HD (1280x720 pixels) which, on a 4-inch display, would result in 275dpi or 367dpi respectively. Putting a 1080p screen on a phone is a complete waste of time (and money) because the human eye cannot distinguish anything greater than about 300dpi;

c)       Playback off screen? Yes: We may see more usage of playing content from the phone onto a larger screen using the TV Out or mini HDMI capabilities of the phone, or maybe even using a built-in pico projector. Nokia has been a strong supporter of TV Out and we will certainly see many more phones in future with a mini HDMI port. As for pico projector phones, I’m not sure that they are going to appeal to the network operators because power consumption will be so poor that the phone will be dead after an hour or two, then there’s no revenue stream for the operators;

d)      Storage: This is where I think there is potential for HD. Using Moores Law, I estimate that in 10 years time the average phone will have 50GB internal memory and some high end phones will have around 1TB of NAND Flash memory, and probably for about the same price as about 32GB of NAND Flash today. What we will do with that memory is another matter. With 1TB you could store about 375 hours of full HD (about 180 movies) so perhaps we will all have our collection of HD movies on our phones ready for viewing when we’re on a business trip for example;

Battery life will certainly be affected by HD though, so we will probably see much bigger batteries (maybe 2000mAh) in handsets with HD capture or playback.

Finally, it's worth noting that several chipset companies have chips in, or close to, production capable of supporting HD capture including TI OMAP 3440 (12MP, 720p); NVIDIA Tegra APX (12MP, 720p); Broadcom 2727 (12MP, 720p); Qualcomm MSM8260 (16MP, 1080p); TI OMAP4 (20MP, 1080p), so it looks like HD capture and storage on phones will be a booming segment.

Stuart Robinson