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Let the Crowd be Heard - A Crowdsourcing-based Study on Video Coding
Zach, Ondřej
In this paper, we present a crowdsourcing-based study on video codec comparison. We compared the perceived quality of sequences encoded using H.264 and H.265 algorithms. The main advantage of the study is, that the users could watch the videos in their natural environment using their own equipment. The results show, that H.265 may not bring a significantly better quality in SD scenarios, however, in other scenarios, the use of H.265 might be preferred.
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Android application for subjective evaluation of video-sequences
Štarha, Dominik ; Přinosil, Jiří (referee) ; Číka, Petr (advisor)
This semestral thesis is focused on a group of four actually used video codecs, namely H.264, HEVC, VP8, VP9. The main objective is to decide on the basis of an evaluation by volunteers which one is the best suitable for video compression. The first part of thesis contains theoretical aspect od the issue. This includes a discussion about the the tested codecs, Android operating system description, performance of the Android Studio software and last but not least, introduction to the assessment methods, used to evaluate video quality, to guarantee the objectivity of the results. The secont part of thesis deals with the implementation of the testing procedure and following evaluation of the data obtained by the assessment.
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Comparison of VP9 and H.265 encoding standards
Fendrich, Vítězslav ; Boleček, Libor (referee) ; Polák, Ladislav (advisor)
This bachelor thesis deals with a comparison of the features of video coding standards VP9 and HEVC (H.265), developed to encoding videos mainly in high resolution. Theoretical part of this work is focused on the presentation and description of both VP9 and H.265 video codecs. Furthermore, objective and subjective metrics for video quality assessment are briefly described. Practical part of this work deals with an evaluation of the quality of video sequences, encoded by VP9 and H.265, with objective metrics and subjective metric. The description of the encoding process using VP9 and H.265 is also included. Proceeding of subjective tests in laboratory conditions is also described. Achieved results are clearly presented and discussed.
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4K real-time video encoding using NVENC technology
Buchta, Martin ; Přinosil, Jiří (referee) ; Kříž, Petr (advisor)
Diploma thesis is focused on real-time 4K video encoding using NVENC technology. First chapter describes the most used video codecs H.264 and HEVC. There is an explanation of the principle of graphic cards and their programmable units. Analysis of the solution of open source Video Codec SDK is also part of the thesis. The main focus of the thesis is an implementation of an application which can handle 4K video encoding from multiple cameras in real time. Performance and qualitative tests were performed for application. Results of these tests were analyzed and discussed.
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Comparison of objective and subjective video quality metrics for Ultra HDTV sequences
Bršel, Boris ; Krasula, Lukáš (referee) ; Kufa, Jan (advisor)
Master's thesis deals with the assessment of quality of Ultra HDTV video sequences applying objective metrics. Thesis theoretically describes coding of selected codecs H.265/HEVC and VP9, objective video quality metrics and also subjective methods for assessment of the video sequences quality. Next chapter deals with the implementation of the H.265/HEVC and the VP9 codecs at selected video sequences in the raw format from which arises the test sequences database. Quality of these videos is measured afterwards by objective metrics and selected subjective method. These results are compared for the purpose of finding the most consistent correlations among objective metrics and subjective assessment.
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Video Quality Measurement for HEVC
Klejmová, Eva ; Veřtát,, Ivo (referee) ; Slanina, Martin (advisor)
This diploma thesis deals with standard objective and subjective video quality assessments and with analysis of their applicability to HEVC. Also basic description of video compression standard H.265/HEVC is presented. The main focus of the thesis is a creation of the database of compressed video sequences. Important parameters and features of the reference encoder HM-12 are discussed. Selected methods of objective video quality assessments are implemented on the created database. A part of this thesis is also a suggestion of method for objective video quality assessment, application of this method and associated data collection. Final data is statistically analyzed and it’s correlation with objective tests is discussed.
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Lossy Light Field Compression
Dlabaja, Drahomír ; Milet, Tomáš (referee) ; Bařina, David (advisor)
The aim of this paper is to propose, implement and evaluate a new lossy compression method for light field images. The proposed method extends the JPEG method to four dimensions and brings new ideas which lead to better compression performance. Correlation between light field views is exploited in both dimensions by four-dimensional discrete cosine transformation. The lossy part of the encoding is performed by quantization, similarly to the JPEG method. The proposed method is implemented as a program library in a C++ language. This paper compares the proposed method to JPEG, JPEG 2000 and HEVC intra image compression methods and HEVC video compression method. The results show that the proposed method outperforms the reference methods with images with a higher amount of views. HEVC video method is better for images with fewer views or for very low bitrates.
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Video and Data Services Quality in the Future Broadband Multimedia Systems and Networks
Kufa, Jan ; Hudec, Róbert (referee) ; Fliegel,, Karel (referee) ; Kratochvíl, Tomáš (advisor)
Téma doktorské práce je zaměřeno na analýzu zpracování signálů v širokopásmových multimediálních sítích a systémech budoucnosti, kde se předpokládají systémy s ultra vysokým rozlišením (UHDTV), vysokým snímkovým kmitočtem (HFR) a stereoskopické systémy (3D). Tyto systémy budou umožňovat vysoce účinnou zdrojovou kompresi obrazu, zvuku a dat a také jejich vysoce účinný přenos, a to jak při volném vysílání (např. DVB-T2), tak ve službách placené televize (např. IPTV). Cílem práce je analýza a vyhodnocení kvality obrazu a služeb v těchto systémech na základě objektivních metrik a subjektivních testů. Práce se dále zaměřuje na analýzu vnímané kvality u stereoskopické televize, kódovací účinnost moderních stereoskopických enkoderů a vlivu sekvencí na uživatelský komfort.
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New video coding algorithms
Zach, Ondřej ; Počta,, Peter (referee) ; Fliegel, Karel (referee) ; Slanina, Martin (advisor)
Předložená dizertační práce se zabývá moderními algoritmy pro kódovaní videosekvencí, zejména algoritmem High Efficiency Video Coding, a jeho použítím v prostředí online streamování. Vzhledem k tomu, že chování koncových diváků směřuje ke sledování video obsahu kdykoli a kdekoli, způsob, jakým je obsah doručen k divákovi, se stává stejně důležitým, jakým je samotné kódování. V této práci se zaměřujeme na užití HEVC ve službách založených na HTTP adaptivním streamování, zejména ve službách využívajích DASH. Dále se zabýváme dalšími aspekty, které mají vliv na kvalitu zážitku (Quality of Experience) tak, jak jej vnímá koncový uživatel. Takovými jsou na příklad přítomnost reklamy či další systémové parametry. Abychom mohli sbírat názory uživatelů, pro naše experimenty často používáme crowdsourcing. Z tohoto důvodu je část této práce věnována samotnému crowdsourcingu a tomu, jak jej lze využít pro hodnocení kvality videa.
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4K real-time video encoding using NVENC technology
Buchta, Martin ; Přinosil, Jiří (referee) ; Kříž, Petr (advisor)
Diploma thesis is focused on real-time 4K video encoding using NVENC technology. First chapter describes the most used video codecs H.264 and HEVC. There is an explanation of the principle of graphic cards and their programmable units. Analysis of the solution of open source Video Codec SDK is also part of the thesis. The main focus of the thesis is an implementation of an application which can handle 4K video encoding from multiple cameras in real time. Performance and qualitative tests were performed for application. Results of these tests were analyzed and discussed.
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