High dynamic range (HDR) images are usually obtained by capturing several images of the scene at different exposures. Previous HDR video techniques adopted the same principle by stacking HDR frames in time domain. We designed a new multi-camera platform which is able to construct and render HDR panoramic video in realtime, with 1024 × 256 resolution and a frame rate of 25 fps. We exploit the overlapping fields-of-view between the cameras with different exposures to create an HDR radiance map. We propose a method for HDR frame reconstruction which merges the previous HDR imaging techniques with the algorithms for panorama reconstruction. The developed FPGA-based processing system is able to reconstruct the HDR frame using the proposed method and tone map the resulting image using a hardware-adapted global operator. The measured throughput of the system is 245 MB/s, which is, up to our knowledge, among the fastest HDR video processing system.

Abstract-This brief analyzes the performance of the hardware-based tone mapping operators for compression of high dynamic range images. The bottlenecks of a tone mapping system are determined and a high-performance field programmable gate array (FPGA) implementation of an operator is introduced. The operator utilizes polynomial mapping technique, adaptive to the pixel values; hence preserving high contrast areas. The technique is further optimized for the presented resource-efficient FPGA implementation. We show that the timing optimization does not reduce the image quality, by obtaining high peak signal-to-noiseratio of the resulting images. The timing comparison to the similar implementations shows 2.5 times increase in the achieved throughput, irrespective of the hardware platform.

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Volumetric ultrasound (US) is a very promising development of medical US imaging. An under-exploited advantage of volumetric US is the mitigation of the strict probe positioning constrains necessary to acquire 2D scans, potentially allowing the decoupling of US image acquisition and diagnosis. However, today's 3D US systems are large and beset by high power and cost requirements, making them only available in well-equipped hospitals. In this study, we propose the first telesonography-capable medical imaging system that supports up to 1024 channels, on par with the state of the art. As a first embodiment, we have implemented our design in a single development FPGA board of 26.7cm×14cm×0.16cm, with an estimated power consumption of 6.1 W. Moreover, we have equipped our platform with an automatic positioning module to help any operator defining the scan location, hence allowing for better remote diagnosis. Our design supports two types of data inputs: real-time via an optical connection and offline over Ethernet. The reconstructed images can be visualized on an HDMI screen. The estimated cost of the proposed prototype materials is less than 4000e.

Volumetric ultrasound (US) is a very promising development of medical US imaging. An under-exploited advantage of volumetric US is the mitigation of the strict probe positioning constrains necessary to acquire 2D scans, potentially allowing the decoupling of US