Lukas Krasula

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The image/video quality is a key issue in security video systems. Therefore the objective image/video quality criteria are extensively studied. In this paper, the novel full reference objective metric for image quality assessment is proposed. This metric is based on FSIM. The ROI detection is embedded in order to improve the performance. For ROI estimation,(More)
The upcoming JPEG XT is under development for High Dynamic Range (HDR) image compression. This standard encodes a Low Dynamic Range (LDR) version of the HDR image generated by a Tone-Mapping Operator (TMO) using the conventional JPEG coding as a base layer and encodes the extra HDR information in a residual layer. This paper studies the performance of the(More)
This paper describes several MATLAB-based applications useful for image processing and image quality assessment. The Image Processing Application helps user to easily modify images, the Image Quality Adjustment Application enables to create series of pictures with different quality. The Image Quality Assessment Application contains objective full reference(More)
The procedures commonly used to evaluate the performance of objective quality metrics rely on ground truth mean opinion scores and associated confidence intervals, which are usually obtained via direct scaling methods. However, indirect scaling methods, such as the paired comparison method, can also be used to collect ground truth preference scores.(More)
The most reliable way to assess the quality of images after a dynamic range compression (i.e. tone-mapping) is a subjective study. The goal of this paper is to determine, whether the preference of the participating subjects is significantly affected by the presence of the original high dynamic range (HDR) image displayed on the HDR screen or if we can(More)
In this paper, the impact of the degree of compression by High Efficiency Video Coding (HEVC) on observers ability of detecting certain events in videos obtained by outdoor CCTV cameras is studied. This was done by extensive subjective testing. The testing was performed also for H.264/MPEG-4 Part 10 AVC compression on similar bitrates and the capabilities(More)
The popularity of high dynamic range (HDR) imaging has grown in both academic and private research sectors. Since the native visualization of HDR content still has its limitations, the importance of dynamic range compression (i.e., tone-mapping) is very high. This paper evaluates observers’ preference of experience in context of image tone-mapping.(More)
Recently, High Efficiency Video Coding (HEVC or H.265) standard becomes to be widely applied and exploited. This compression standard can achieve very low video bitrates and allow deployment of mobile security cameras with wireless data transmission. The paper deals with subjective evaluation and assessment of the above mentioned standard and its impact on(More)
Assessment of multimedia quality relies heavily on subjective assessment, and is typically done by human subjects in the form of preferences or continuous ratings. Such data is crucial for analysis of different multimedia processing algorithms as well as validation of objective (computational) methods for the said purpose. To that end, statistical testing(More)