Bruno Zatt

Universidade Federal de Pelotas | UFPEL · Department of Computer Engineering

The emerging of 3D video-capable embedded mobile devices is expected due to the popularization of multimedia services and the demand for novel immersive video technologies. Such devices require efficient hardware-friendly heuristics to deal with strict processing requirements and limited energy supply. To contribute to these requirements, this work...

Network congestion and packet loss pose an ever-increasing challenge to video streaming. Despite the research efforts toward making video encoding schemes resilient to lossy network conditions, forwarding devices have not considered monitoring packet content to prioritize packets and minimize the impact of packet loss on video transmission. In this...

This article describes a framework to speed up the HEVC encoding decisions for on-demand transrating of bitstreams. The methods proposed collect information from a high-quality reference bitstream which after processing is used to limit the number of modes evaluated in subsequent re-encodings at different bitrates. In this way, the time required to...

After the AOMedia Video 1 (AV1) bitstream specification was launched by the Alliance for Open Media, the need for converting legacy content encoded with the state-of-the-art High Efficiency Video Coding (HEVC) standard to the new format has arisen in several scenarios. However, transcoding is a complex task composed of a decoding and an encoding pr...

The digital video coding process imposes severe pressure on memory traffic, leading to considerable power consumption related to frequent DRAM accesses. External off-chip memory demand needs to be minimized by clever architecture/algorithm co-design, thus saving energy and extending battery lifetime during video encoding. To exploit temporal redund...

Background Changes in soluble amyloid-beta (Aβ) levels in cerebrospinal fluid (CSF) are detectable at early preclinical stages of Alzheimer’s disease (AD). However, whether Aβ levels can predict downstream AD pathological features in cognitively unimpaired (CU) individuals remains unclear. With this in mind, we aimed at investigating whether a comb...

Positron emission tomography (PET) imaging plays a key role in the diagnosis of Alzheimer’s disease (AD). The idea of integrating PET and omics data can provide blood‐new insights about AD pathophysiology. In this context, state‐of‐the‐art techniques such as transcriptomics hold much potential for discovering altered biological processes in AD and...

The encoding of 360 videos presents many challenges. These spherical videos require a planar projection stage prior to encoding, and there are no studies on how projection interferes with the encoder decisions. Also, due to the increased resolution, encoding 360 videos is computationally costlier than conventional videos. In this work, we perform a...

Background: Changes in soluble amyloid-beta (Aβ) levels in cerebrospinal fluid (CSF) are detectable at early preclinical stages of Alzheimer's disease (AD). However, whether Aβ levels can predict downstream AD pathological features in cognitively unimpaired (CU) individuals remains unclear. With this in mind, we aimed at investigating whether a com...

This work presents an energy-efficient NoC-based system for real-time multimedia applications employing approximate computing. The proposed video processing system, called SApp-NoC, is efficient in both energy and quality (QoS), employing a scalable NoC architecture composed of processing elements designed to accelerate the HEVC Fractional Motion E...

This paper presents FastInter360, a fast inter mode decision algorithm for accelerating the encoding of ERP 360 videos. The development of FastInter360 involves an in-depth and comprehensive set of evaluations performed to understand the differences in the encoder’s behavior when encoding 360 and conventional videos. These evaluations showed that d...

Approximate computing techniques exploit the characteristics of error-tolerant applications either to provide faster implementations of their computational structures or to achieve substantial improvements in terms of energy efficiency. In video encoding, the motion estimation (ME) stage, including the Integer ME (IME) and the Fractional ME (FME) s...

This article presents an extensive review of the state-of-the-art system-level solutions featuring complexity reduction and/or dedicated hardware designs for the AV1 and VVC video coding formats. These formats introduced several novel coding techniques compared to their predecessors to improve the coding efficiency at the cost of a significant comp...

Video coding applications demand high computational effort to achieve high compression rates at a low perceptual quality expense. In order to reach acceptable encoding time for such applications, modern video coding standards have been em-ploying parallelism approaches to exploit multiprocessing plat-forms, such as the tiling tool from HEVC standar...

Positron emission tomography (PET) imaging has been playing a fundamental role in diagnosis of Alzheimer’s disease (AD). Also, in the context of AD, blood‐based biomarkers that are capable of predicting PET brain imaging findings are of high interest. Both PET imaging and transcriptomics are rich sources of different biological information. Hence,...

This paper presents an extensive evaluation of the HEVC parallel video coding when using Tiles. The evaluation consists on finding the tiling pattern that yields the maximum possible speedup for a set of video sequences considering several encoding parameters, measuring the coding efficiency variation of using such tiling pattern instead of the uni...

Real-time digital video coding became a mandatory feature in current consumer electronic devices due to the popularization of video applications. However, efficiently encoding videos is an extremely processing/energy-demanding task, especially at high resolutions and frame rates. Thus, the limited energy resources and the dynamically varying system...

This paper presents a complexity and compression efficiency assessment of the 3D-High Efficiency Video Coding (3D-HEVC) encoder. An experimental evaluation was carried out to identify the encoding tools with the highest impact on the computational complexity of 3D-HEVC. The evaluated tools were firstly divided into three categories: HEVC, multiview...

The most common operation to maintain various versions of the same video sequence under different bitrates in live and streaming video applications is video transrating. The typical transrating operation is comprised of a decoding and a complete encoding step in sequence, which results in long processing times and high energy consumption. This work...

This paper presents a memory assessment of the next-generation Versatile Video Coding (VVC). The memory analyses are performed adopting as a baseline the state-of-the-art High-Efficiency Video Coding (HEVC). The goal is to offer insights and observations of how critical the memory requirements of VVC are aggravated, compared to HEVC. The adopted me...

Video encoding draws high research interest, due to the enormous demand for video traffic and real-time encoding for transmission. In video encoding standards such as HEVC (High-Efficiency Video Coding), the final step of the encoding stage is the CABAC (Context-Adaptive Binary Arithmetic Coding). The coding efficiency of the CABAC comes at the cos...

The 3D-HEVC is the state-of-art encoder for 3D videos. This article focuses on the 3D-HEVC depth-map intra prediction. Novel heuristics to reduce the computational effort are explored to design a high-throughput architecture, which supports both the 3D-HEVC tools and the tools inherited from the HEVC. The synthesis results were generated targeting...

With the recent rise in artificial intelligence, several areas of computer science have begun to explore the use of machine learning algorithms. Among them, recent video encoding techniques exploit in large-scale machine learning algorithms, either to aid in compression efficiency or to reduce computational cost. However, this is not a simple task,...

This article presents a framework for assessing the behavior and energy impact of cache hierarchies when encoding HEVC on general-purpose processors. The memory energy estimation framework estimates energy consumption of cache hierarchies based on mathematical models combined with memory access profiling tools. The energy analysis of several cache...

Today, several applications running into embedded systems have to fulfill soft or hard timing constraints. Video applications, like the modern High Efficiency Video Coding (HEVC), e.g., most often have soft real-time constraints. However, in specific scenarios, such as in robotic surgeries, the coupling of satellites and so on, harder timing constr...

This paper presents a dedicated hardware design for the DC and Chroma from Luma (CFL) intra-prediction modes of AV1 decoder. The hardware was designed to reach real-time when processing UHD 4K videos. The AV1 codec is an open-source and royalties-free video coding, which was developed by the AOMedia group, this group is composed of multiple compani...

Video processing is a topic of major interest due to the demand for real-time delivery of increasing resolution videos. Moreover, Internet traffic related to high-quality video processing tends to be the dominant type of information transmitted. The high-efficiency video coding (HEVC) standard is a suitable and efficient choice to overcome the chal...

The 3D-HEVC adopts the Disparity Estimation to efficiently reduce the Inter-view redundancies, which occur when the same scene is captured from different positions. Since the camera arrangement usually follows a horizontal alignment, horizontal disparities are more common. So, this paper presents a dedicated hardware to perform the Disparity Estima...

This brief presents a high-throughput hardware design for the motion compensation (MC) sub-sample interpolator of the novel AOMedia video 1 (AV1). A multifilter interpolation architecture (MFIA) is presented targeting AV1 decoders and supporting all 90 filters defined by the AV1 MC. The MFIA uses shift-adds instead of multipliers and common subexpr...

Recent technological advancements allowed videos to come from a simple sequence of 2D images to be displayed in a flat screen display into spherical representations of one’s surroundings, capable of creating a realistic immersive experience when allied to head-mounted displays. In order to explore the existing infrastructure for video coding, 360-d...

One of the most concerning issues in current video coding systems relies on the bottleneck caused by the intense external memory access required by motion estimation. As memory access affects directly the energy consumption, this problem becomes more evident when battery-powered devices are considered. In this sense, this article presents the Doubl...

Video transrating has become an essential task to allow the transmission of different versions of the same video in streaming services and live applications. However, as the transrating operation comprises a decoding and an encoding step in sequence, it demands high processing time and energy consumption, which is prohibitive in large-scale systems...

Real-time operation and low-power dissipation in video coding systems have become important research challenges, especially in mobile devices with limited battery and computational resources. Given the variety of applications able to manipulate videos and the growing number of video coding standards, current devices are expected to provide native s...

HEVC is one of the most recent video coding standards, designed to face a new age of video processing challenges, such as higher video resolutions and limited traffic share bandwidth. The HEVC standard is divided into multiple steps, whereas the entropy encoding is the final stage before the coded bitstream generation. The CABAC (Context Adaptive B...

High abstraction level models can be used within the system-level simulation to allow rapid evaluations of architectural aspects in early Design Space Exploration (DSE) and direct the development decisions. Further, early DSE is of paramount importance in the specification of future Embedded Systems (ES) and its evaluation for applications with hig...

A hybrid scratchpad video memory (Hy-SVM) for energy-efficient Tiles-parallelized High-Efficiency Video Coding (HEVC) is presented herein. The key ideas of Hy-SVM include: application-specific design and management; combined multiple levels of private and shared memories that jointly exploits intra-Tile and inter-Tiles data reuse; scratchpad memori...