Open source pixels

The other day I noticed a menu option on the iPod Touch called "Legal". Normally, I avoid reading such legal notes, but this time I was curious to see what was mentioned here. Well, a lot was mentioned. It took me 76 "scroll-the-page-down" strokes to reach the bottom of the long list of legal speak. Most interesting fact; more than 3/4 of the notes were open source related! I saw the GPL come by several times for instance.

Anyone dare to estimate how much total effort it took to develop all the software shipped with the iPod Touch, including the effort put into the open source software? Are your SOCs and video subsystems ready to support open source software?

Acquired pixels

Recently, DivX acquired MainConcept for approximately $22M. MainConcept is a developer of mostly PC-based video codecs, which is the business that DivX is in also.

Which video company will be acquired next?

Shiny pixels at Qualcomm

CRT, LCD, TFT, OLED, EPD and DLP are just some of the many acronyms used for the techniques behind displays. There's an article in the November 2007 issue of Scientific American that presents a new acronym: IMOD. The IMOD displays are based on many small interferometric modulators, which bounce back light at different intensities. They don't need a backlight, which means power consumption is much lower, ever so important for portable applications. The viewing experience is also greatly enhanced I am sure. The electronic paper displays that I've seen don't use a back-light either and they're great. They read like paper. The e-ink pixels change intensities too slowly to show video though, while the IMOD technology is very fast. The whole technology reminds me of the, also MEMS-based, DLP from Texas Instruments. Within a few years, that technology quickly became prevalent in projectors, beating out LCD.

With better displays, video coding artefacts will only become more apparent. Is your video subsystem ready to capture and play the highest quality video?

Crummy pixels on my iPod Touch

I recently bought an iPod Touch. The WiFi integration is neat and worked straight out of the box. I now have a pocketable Internet browser, and it even connects directly to YouTube, using the new H.264 codec instead of YouTube's default and inferior Flash codec that the PC-based website uses.

After playing a few videos something interesting happened. The video codec shows very crude artefacts. See the picture below. I haven't found many other iPod users on the web complaining yet, but it's hard to believe I am the only one. Will Apple be able to fix this with a firmware upgrade? If the rumoured Samsung chip at the heart of this device uses a hard-wired video coding subsystem, they likely won't be able to fix the issue quickly in software. Instead, they will have to respin the chip and people will have to return their devices and get new ones months later. Chip inventory will have to be trashed. A reset fixed the issue for me, but it has shown up again.

Are you an SOC designer that still uses hard-wired video codecs? Can you risk designing an SOC that requires a silicon respin to resolve issues that could have been solved in software if a programmable approach had been chosen?

Scalable pixels

H.264 was standardized quite a while ago in 2003 and brought a "back to basics" compress-video-only approach compared to the feature-laden MPEG-4. So what are the ISO and ITU video standardization gurus working on these days? They're working on SVC, short for scalable video coding. The goal this time is not to achieve a higher coding gain, but instead to make the bitstream scalable.

In SVC, a same single bitstream can be decoded at different resolutions or frame rates. If you're watching the stream on your 1080p big screen TV at home you decode all the bits, and in case you want to play the same stream on your mobile phone, just decode those pixels that you need for the small screen. There are many applications for scalable video coding, but I've seen the concept many times before and people just don't use it. JPEG2000 is scalable. MPEG-4 had a few scalable profiles, even MPEG-2 had scalable extensions. None of them are widely used today. Why? Because there's overhead involved in making a bitstream scalable. A scalable bitstream is larger than a non-scalable one. Also, most system engineers find it simply more practical to just recompress the bitstream for each specific target device. Pixar and Dreamworks even completely re-render their 3D movies dependent on whether it's for the theater or for a DVD. Compressing the resulting video sequence another time doesn't seem that much of an extra burden.

Will things be different this time? Will SVC become a prevalent standard?

Sluggy pixels

My brother is an artist. One of his friends made this low-resolution and very-low-frame-rate imaging device. It's called the PingPongPixel and displays one image every 2.5 hours. That's about 0.0001 frame per second. Hardly practical, but still pretty nifty. Each pixel is represented by a ping-pong ball, which come in 6 shades of gray.

Anybody know of a display device with an even lower refresh rate?