CAS-CNN: A Deep Convolutional Neural Network for Image Compression Artifact Suppression

Lossy image compression algorithms are pervasively used to reduce the size of images transmitted over the web and recorded on data storage media. However, we pay for their high compression rate with visual artifacts degrading the user experience. Deep convolutional neural networks have become a widespread tool to address high-level computer vision tasks very successfully. Recently, they have found their way into the areas of low-level computer vision and image processing to solve regression problems mostly with relatively shallow networks. We present a novel 12-layer deep convolutional network for image compression artifact suppression with hierarchical skip connections and a multi-scale loss function. We achieve a boost of up to 1.79 dB in PSNR over ordinary JPEG and an improvement of up to 0.36 dB over the best previous ConvNet result. We show that a network trained for a specific quality factor (QF) is resilient to the QF used to compress the input image - a single network trained for QF 60 provides a PSNR gain of more than 1.5 dB over the wide QF range from 40 to 76.Comment: 8 page

Tackling the Bottleneck of Delay Tables in 3D Ultrasound Imaging

3D ultrasound imaging is quickly becoming a refer- ence technique for high-quality, accurate, expressive diagnostic medical imaging. Unfortunately, its computation requirements are huge and, today, demand expensive, power-hungry, bulky processing resources. A key bottleneck is the receive beamforming operation, which requires the application of many permutations of fine-grained delays among the digitized received echoes. To apply these delays in the digital domain, in principle large tables (billions of coefficients) are needed, and the access bandwidth to these tables can reach multiple TB/s, meaning that their storage both on-chip and off-chip is impractical. However, smarter implementations of the delay generation function, including forgoing the tables altogether, are possible. In this paper we explore efficient strategies to compute the delay function that controls the reconstruction of the image, and present a feasibility analysis for an FPGA platform

The Logic of the ‘As If’ and the Existence of God: An Inquiry into the Nature of Belief in the Work of Jacques Derrida

The religious thematics at play in the work of Jacques Derrida have often provided an ongoing platform from which to struggle with the entire scope of his work, thus moving the seemingly peripheral discourses on religion within his oeuvre to the center stage. Despite repeated attempts to come to terms both theologically and philosophically with the conditional nature of representations, the problematics of representation are perhaps nowhere more forcefully demonstrated than in the work of Derrida. Indeed, for Derrida, the ‘as if’, as a regulative principle directly appropriated and modified from its Kantian context, becomes the central lynchpin for understanding, not only Derrida’s philosophical system as a whole, but also his numerous seemingly enigmatic references to his ‘jewishness’, as I intend to demonstrate in what follows. Through an analysis of the function of the ‘as if’ within the history of thought, from Greek tragedy to the poetry of Wallace Stevens, I hope to show how Derrida can only appropriate his Judaic roots as an act of mourning that seeks to render the lost object as present, ‘as if’ it were incorporated by the subject for whom this act nevertheless remains an impossibility. As Derrida discerns within the poetry of Paul Celan, bringing a sense of presence/presentness to our experiences, and as a confirmation of the subject which the human being struggles to assert, is the poetic task par excellence. It is seemingly also, if Derrida is to be understood on this point, the only option left to a humanity wherein poetry comes to express what religious formulations can no longer justify

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

LightProbe: A Digital Ultrasound Probe for Software-Defined Ultrafast Imaging

Digital ultrasound probes integrate the analog frontend in the housing of the probe handle and provide a digital interface instead of requiring an expensive coaxial cable harness to connect. Current digital probes target the portable market and perform the bulk of the processing (beamforming) on the probe, which enables the probe to be connected to commodity devices such as tablets or smartphones running an ultrasound app to display the image and control the probe. Thermal constraints limit the number of front-end channels as well as the complexity of the processing. This prevents current digital probes to support advanced modalities such as Vector Flow or Elastography requiring high-frame rate (HFR) imaging. In this paper, we present LIGHTPROBE, a digital ultrasound probe, which integrates a 64-channel 100 Vpp TX/RX frontend including analog-to-digital conversion (up to 32.5 MS/s @ 12 bit), and is equipped with an optical high-speed link (26.4 Gb/s) providing sustainable raw samples access to all channels, which allows the processing to be performed on the connected device without thermal power constraints. By connecting the probe to a GPU-equipped PC, we demonstrate the flexibility of softwaredefined B-mode imaging using conventional and ultrafast methods. We achieve plane-wave and synthetic aperture imaging with frame-rates from 30 Hz up to 500 Hz consuming between 5.6W and 10.7W. By using a combination of power and thermal management techniques, we demonstrate that the probe can remain within operating temperature limits even without active cooling, while never having to turn the probe off for cooling hence providing a consistent Quality of Service for the operator.ISSN:0885-3010ISSN:1525-895

STB-SASB: Combining Synthetic Aperture Sequential Beamforming with Synthetic Transmit Beams for Wireless Ultrasound Probes

none2siWireless ultrasound probes typically perform beamforming on the probe and communicate B-mode images to meet bandwidth constraints of wireless links. Performing on-probe beamforming is thermally-bound, hence wireless probes typically only provide limited capabilities compared to cart-based systems.In this work, we apply Synthetic Aperture Sequential Beamforming (SASB) to enable beamforming "after" the wireless link, i.e., on the mobile device connected with the wireless probe. SASB enables wireless transmission of the data by performing only simple operations on the probe. The compute-intensive part of the image formation is performed on the connecting device. However, SASB consumes much energy in the analog front-end compared to other methods such as diverging beams imaging.In this paper, we present the first (to the best of our knowledge) working prototype of a 64-channel wireless ultrasound probe performing SASB. The prototype allows comparing the energy-consumption and image quality of SASB with other methods. To improve the energy-consumption, we propose STB-SASB, a combination of SASB with synthetic transmit beams (STB). STB-SASB with two synthetic beams reduces the front-end consumption by 50% with ideal power management. On our system, we demonstrate savings of 31% with a minor quality degradation of 6% in resolution (FWHM). More synthetic beams reduce the consumption even further at the cost of quality.mixedHager P.A.; Benini L.Hager P.A.; Benini L