Camera-phone boundary blurs, but images get sharper
- 21 February, 2005 07:31
It can only be a matter of time before we talk of calling someone with our camera, as the resolution and capabilities of the imaging components in mobile phones continue to climb. At the 3GSM World Congress in Cannes last week, manufacturers showed off a number of technologies that render the line between phones and cameras more blurry -- but make the pictures they produce ever sharper.
Cameras typically allow a great deal of control over factors such as exposure and focus at the moment the picture is taken, whereas phones typically have one control: take a picture. Some cameras try to give users the control they seek after the fact with a range of functions for editing stored images, but these are often limited in capability.
Two companies exhibiting in Cannes -- Scalado, and DxO Labs -- demonstrated image processing software for camera phones that improves image quality in different ways.
Scalado demonstrated software to solve one of the hidden problems of image editing on mobile phones: lack of memory. While a two-megapixel image might only occupy a few hundred kilobytes of memory in compressed JPEG format, editing such images has traditionally involved decompressing them into a full-size bitmap image of about 6M bytes and performing operations on a copy of that image -- requiring around 12M bytes of memory in total. If this memory is not available, then editing photos may only be possible at greatly reduced resolution, defeating the object of putting a high-resolution camera in the phone in the first place, according to Pierre Elzouki, Scalado's vice president of business development.
The company's Caps software libraries perform operations such as color correction, picture rotation, image compositing and pixel editing directly on the compressed version of the image, reducing the memory required for editing the same two-megapixel image to less than a megabyte, he said. By reducing the requirement for memory and processor power in the phone, the software can cut phone costs by between US$1 and US$5, Elzouki said.
Scalado sells its software in several ways. Phone manufacturers can license the image processing code for use in their own applications. They can also license broader functions or complete applications such as Photo Twister, which distorts images in real time, swelling and shrinking parts of the image much like the curved mirrors in a funhouse. Finally, owners of smart phones based on Symbian OS can download such applications from online services such as Handango, Elzouki said.
DxO Labs showed its DxO Mobile Embedded Edition software running on an Omap DM275 imaging processor from Texas Instruments Inc. (TI). The software corrects for image defects such as noise, color imbalance and low contrast introduced by digital image sensors by applying a variety of mathematical techniques to a model of the image sensor, the company said.
At low light levels, noise becomes a problem with digital image sensors. DxO uses a recently developed mathematical technique in its DxO Noise software to reduce the effect of noise on the image, which allows cameras to produce the same image quality with just a quarter of the ambient light, according to the company, which demonstrated the software at TI's booth. Another program, DxO Contrast, applies varying contrast settings to different parts of the image, to make fine detail in shadows or bleached-out parts of the image more visible.
Although the techniques are equally applicable to camera phones and dedicated cameras, they may be more valuable in phones, where users tend to edit and share their photos without first transferring them to a PC.
Scalado and DxO both maintained that there's more to picture quality than increasing the number of megapixels in the image sensor, but that didn't stop companies from touting sensors with higher and higher resolution. LG Electronics Inc. showed its LT1000 phone, with a 1.3 megapixel camera -- and a built-in TV tuner into the bargain. Panasonic Mobile Communications showed its VS3 and VS7 phones, also with megapixel cameras.
Motorola showed its own answer to the problem of image quality at low light levels: Its E1120, a 3G (third generation) phone for the European market, has a built-in 30-lux lamp, and ups the stakes on resolution with a three-megapixel camera.
Micron Technology Inc. of Boise, Idaho, announced a two-megapixel image sensor with a built-in JPEG compression engine. Including this on the camera chip eliminates the need for a second chip to do the compression, which means phones can be made smaller and cheaper, the company said. Samples of the chip will be generally available beginning in April, it said.
Mitsubishi Electric showed imaging components in a range of capacities up to two megapixels, and said it plans to introduce a four megapixel version "soon."
Back on dry land, Nokia showed its 6680 Imaging Smartphone for 3G networks, with a 1.3 megapixel camera on one side and a 0.3 megapixel resolution camera on the other. The launch marks something of an about-face for Nokia, which has until now maintained that people were more interested in sending images of what they can see than they are in face-to-face videoconferencing. With the 6680, they can do both, Nokia said.
Mobile network operators encourage their customers to use devices such as the 6680 to share pictures in electronic format, but some people still like to pass their holiday snaps around on paper. Eastman Kodak Co. has developed an online photo album hosting service bringing both worlds together, and this week announced deals with three European network operators to offer cobranded portals to their customers. Photos can be uploaded to the portals from a phone by MMS (Multimedia Messaging Service), or directly from a PC over the Internet. They are then published as Web pages, and visitors can order prints over the Web or from their phones.
The photos can be delivered by mail to anywhere in the world using Kodak's Easyshare Gallery printing service, the company said. The service will be available on mmO2's U.K. network, O2, from March; on T-Mobile International AG & Co. KG's U.K., German and Austrian networks from April, and on the French network of Societe Francaise du Radiotelephone SA (SFR) from May. Creating an account to host the photos is free, but network operators set their own charges for sending MMS messages to the service, and Kodak will charge Euro 0.29 (US$0.38) for each print ordered, plus a shipping fee, a company spokesman said.
The 3GSM World Congress closed Thursday.