Digging Into 'DIGIC 4' Image Processor (1)

Feb 17, 2009
Tomohiro Otsuki, Nikkei Electronics

Canon Inc's DIGIC series image processors for cameras are some of the few consumer SoCs that are made in Japan and have been very successful for a long period of time.

The DIGIC series is used in a wide range of products, from the most affordable compact cameras to SLR models, thereby providing high functionality at a low cost. And Canon debuted the fourth-generation DIGIC processor, "DIGIC 4," in cameras released in 2008.

What's inside the Digic 4? We examined the physical aspects of the processor with the help of Van Partners Corp, a company specializing in LSI analysis.

First, we tried out the Ixy Digital 920IS, a digital camera equipped with the DIGIC 4, and disassembled it.

One of the main features of the DIGIC 4 cameras is a function to detect and track faces. Though Canon has not revealed the parameters used in the processing, another company realized a similar function by using color information.

So, we tried shooting photos of two cats and found a big difference. The white cat came into focus even when it looked away, while it was impossible to detect the face of the tiger striped cat. It is possible that Canon, too, adopted an algorithm to detect and track faces based on color information.

After we started breaking down the camera, we noticed that it looked more difficult to assemble than other compact cameras that we had torn down before. It had a greater number of small plastic parts and a wider variety of screws to fasten these parts although the comparison is not based on detailed data. It is possible that we were surprised partly because we had the preconception that this was one of the top-selling models in the camera industry.

Next, we examined the removed parts. The components mounted on the mainboard and around the image sensor as well as the motor were all standard parts. This might make my article boring, but it is certainly better for manufacturers not to use exceptional techniques.

In the next article, we will remove the DIGIC 4 from the mainboard and melt the semiconductor package. We will also report on the results of observation using an optical microscope and SEM (scanning electron microscope).