Search

This paper presents the implementation of a sensor-shift image stabilization system for a small form factor camera. Image stabilization is a family of techniques for reducing image blur resulting from minute camera shake due to hand-held shooting, thereby allowing the use of shutter speeds slower than values normally required to obtain sharp images. A prototype sensor-shift type image stabilizer module developed for a camera mobile phone is introduced and a digital control system as a part of the image stabilization system is designed and implemented on an 8-bit microcontroller through integer arithmetic in the C language. This paper focuses primarily on issues that need to be taken into consideration for fixed-point implementation of the digital controller. Experimental results are presented to demonstrate the performance of the implemented sensor-shift image stabilization system. Index Terms--image stabilization, digital camera, fixed-point implementation, digital controller.

The mobile imaging market is a rapidly developing market, and has outgrown the traditional imaging market. This market is dominated by CMOS sensors, with pixels getting small and smaller. As pixel size is reduced, the sensitivity is lowered and must be compensated by longer exposure times. However, in the mobile market, this amount to increased motion blur. We characterize the hand motion with a typical shooting scenario. This data can be used to create an evaluation procedure for image stabilization solutions, and we indeed present one such procedure (1). Index Terms--hand motion, image stabilization, mobile imaging.

Print-from-video can be achieved by using super-resolution techniques. These techniques involve combining information from multiple low resolution images to generate and print a high resolution image. Among the existing super-resolution techniques, the most suitable one for deployment on portable consumer electronics products, in particular on cell-phones, that have limited processing and memory resources is the shift-and-add approach. However, this approach is known to generate artifacts when applied to real video sequences. This paper introduces a number of improvements made to the shift-and-add approach in terms of frame alignment, frame selection, and frame fusion to reduce such artifacts in computationally efficient manner. In addition, a post-processing step named pattern filtering is applied to reduce visual artifacts in printed images. The effectiveness of the developed solution is demonstrated by showing both quantitative and qualitative comparison results for video sequences captured by cell-phone cameras (1). Index Terms--Fast print-from-video, cell-phone cameras, pattern filtering, outlier reduction, super-resolution.

We have developed a new image stabilization method that utilizes electric charge transfer in the vertical transfer register of a CCD image sensor. This method repeats a series of actions including one or more continuous exposures according to the degree of camera shake, transferring, and adding electric charges in the vertical transfer registers to correct image blurs. This method can only correct blurs in the direction parallel to the vertical transfer registers, however it does not require mechanical components, external memory, or digital image processing circuits. Consequently, we can apply it in the direction of a single axis when executing biaxial blur correction to a camera that performs blur correction by means of drive control of the optical system in order to realize more compact cameras and reduce costs (1). Index Terms--CCD, time delay integration, electric charges, digital cameras, image-stabilization.

In order to enable the real-time image mosaic in mobile devices that have very limited computing power and memory, we propose an efficient image mosaic algorithm with integer arithmetic. The proposed algorithm is focused not only on the computational efficiency, but also on the performance improvement of image mosaic. For the efficient projection without transform estimation, we obtain successive images through the semitransparent view finder which shows the fixed amount o fright part of previously captured image. We project each images onto cylindrical surface by the proposed projection equation and integer arithmetic. We align the projected images by hierarchical hexagon search and a matching measure that is robust to illumination changes caused by different exposures and vignette distortion. Finally, the images are naturally blended using color compensation and dynamic programming based stitching. The proposed mosaic algorithm is embedded and tested in mobile phone systems. According to various tests and experiments, the proposed algorithm shows good panorama composition in real-time compared with the other PC-based methods (1). Index Terms--Embedded panorama mosaic, color compensation, integer arithmetic, stitching

Consumer digital cameras usually use a single light sensor together with a color filter array (CFA) for capturing color images. This results in a mosaic image being captured, where only one color sample (red, green or blue) is obtained at each pixel location. Demosaicking is the process of interpolating the two missing color samples at each location to generate a full color image. Virtually all current demosaicking methods produce an RGB output image. If the image is to be compressed afterwards, it will typically be converted from RGB to YCbCr 4:2:0 format. In this paper we propose a new demosaicking method that directly produces an YCbCr 4:2:0 image, so the output can be directly compressed. Simulation results show that the proposed method provides higher image quality than fast RGB based demosaicking methods and has lower computational complexity. Index Terms--demosaicking, color filter array, YCbCr color space, digital cameras.

In this paper, we have proposed a security camera system that displays high-definition images by using a sharply outlined display algorithm (SODA), which generates less hardware complexity because of a modified video encoder. While the proposed system uses a Charge Coupled Device (CCD) with a complementary filter that may cause some problems in representing vivid color, we have been able to resolve the problem by mixing two signals, such as those generated by chrominance and luminance processes. In doing so, the system requires the use of a video encoder that converts the CCD's output signals into a Composite Video Baseband Signal (CVBS). Moreover, although a video encoder generally operates at 27MHz the CCD module used in the security camera requires a particular clock frequency. Here, we have proposed that the new video encoder uses a clock to equal the CCD module at a given frequency. In doing so, the system using the encoder reduces hardware complexity and noise. The proposed system is fabricated with a test camera chip that has been manufactured by the MagnaChip 0.25um CMOS process. Index Terms--Digital Camera, CCTV, CCD, Video Encoder.

This paper presents a color processing architecture for digital color cameras utilizing Complementary Metal Oxide Semiconductor (CMOS) image sensors. The proposed architecture gives due consideration to the peculiar aspects of CMOS image sensors and the human visual perception related to the particular application of digital color photography. A main difference between the proposed method and the conventional systems is the fact that color correction module is located before the interpolation module. Therefore, a method of performing color correction on a color filter array (CFA) pattern is also provided in this paper. The interpolation algorithm is especially designed to solve the problem of pixel cross talk among the pixels of different color channels. The algorithm separates the green channel into two planes, one highly correlated with the red channel and the other with the blue channel. These separate planes are used for red and blue channel interpolation. The implementation details related to managing four color channel values is also described. Experiments conducted on McBeth color chart and natural images have shown that the proposed color processing chain produces better quality images with improved SNR. Index Terms--color correction, color interpolation, color processing architecture, pixel cross talk.

We present an embedded software-based automatic calibration system for high-end digital still cameras. By using electronic shutter associated with charge-coupled device (CCD), the system can be used to calibrate the characteristics of the sensor, the mechanical shutter, and the lens accurately. It has been built in several camera models and applied on a practical mass production line. The calibration time for each camera is less than 30 seconds and the calibrated cameras can get very high precision parameters for controlling image capture function. Index Terms--Digital still camera, calibration, CCD sensor, mechanical shutter.

Photography was solely a black-and-white process until 1860, when James Clerk Maxwell discovered that color photographs could be formed using red, blue and green filters. Maxwell photographed a tartan ribbon [...]

The second AF digital SLR to break the under-$1000 price barrier, Nikon's D70 is a 6.1-megapixel model with a lot going for it besides the low price, including excellent performance, […]

With their instant feedback, reusable media, and excellent image quality, today's digital cameras offer great advantages over their film counterparts. What's more, most digital cameras provide intelligent auto modes that […]

Interconnectivity of digital camera with other devices is one of the main concerns of consumers and digital camera manufacturers. Interconnectivity features in digital cameras allow more consumer-friendly usage of digital cameras. Moreover, with a suitable application layer software, digital photographs can be sent directly from the camera to a desired target: disk storage, printer, web site, as an e-mail message or web print, using a single, purpose-designed, communication protocol: the Picture Transfer Protocol, PTP.