|
|
Comparison of Modern Lossy Image Compression Formats
Kalabza, Marek ; Klíma, Ondřej (referee) ; Bařina, David (advisor)
This thesis compares modern compression methods of digital images on given datasets in terms of quality. First part describes the principle of lossy compression and then compression of JPEG, Lepton, JPEG 2000, JPEG XR, WebP, BPG, HEIF, H.265 intra frame, H.264 intra frame and AV1. Second part focuses on testing, comparison of results and evaluation. It also describes quality metrics (PSNR, PSNR-YUV, SSIM), deals with possible artefacts created during compression and points out the behavior of formats after data corruption. Based on testing and measurement, it was found that the best compression format from the tested lossy image formats is the AV1 format, specifically on the high resolution dataset, the scanned document dataset, and the map dataset.
|
|
|
ECG quality estimation
Pospíšil, Jan ; Smíšek, Radovan (referee) ; Smital, Lukáš (advisor)
This bachelor thesis deals with the question of estimation of the quality of the ECG signals, which is a key parameter for determining the diagnosis. The theoretical part deals with the basic knowledge concerning cardiac physiology, electrocardiography and finally the types of interferences that can occur during the measurement. The following practical part will deal with the published methods and the proposal of methods for estimating signal quality and their testing on artificial and real data.
|
|
|
ECG quality estimation
Pospíšil, Jan ; Smíšek, Radovan (referee) ; Smital, Lukáš (advisor)
This bachelor thesis deals with the question of estimation of the quality of the ECG signals, which is a key parameter for determining the diagnosis. The theoretical part deals with the basic knowledge concerning cardiac physiology, electrocardiography and finally the types of interferences that can occur during the measurement. The following practical part will deal with the published methods and the proposal of methods for estimating signal quality and their testing on artificial and real data.
|
|
|
Cone Be am CT in dentistry: Motion artifacts and their reduction
Hanzelka, Tomáš ; Beneš, Jiří (advisor) ; Charvát, František (referee) ; Mazánek, Jiří (referee)
Cone Beam Computed Tomography (CBCT) allows effective 3D imaging in dentistry. CBCT consists of a planar detector and a x-ray source that rotate once around patient`s head. The x-ray beam is cone-shaped and is directed through the whole volume of interest. All the data needed are obtained during a single rotation of the source and detector. This rotation takes from several to several tens of seconds, and during this time the CBCT captures several hundred of 2D images. They represent different points of view on the region of interest and are later reconstructed to form a 3D data set. The biggest advantage of CBCT is that it can produce 3D image using at radiation doses similar to those of conventional diagnostic methods used in dentistry (Pauwels et al., 2010). In the experimental part of our experiment, we address one of the biggest weaknesses of CBCT - patient movement during scanning which has a major impact on the image quality and is currently the main limiting factor in the further development of this technology. In the first part of our experiment, we recorded movements of patients and CBCT scanner using a high speed camera and subsequently analyzed the data in MatLab program. Significant level of patient motion as well as motion of CBCT scanner was demonstrated. Motion was highest at the...
|
|
|
Clothing as a cultural artifact and its current use in art lectures at primary education
Melounek, Robin ; Kovandová, Anna (advisor) ; Jakubcová Hajdušková, Lucie (referee)
Melounek, R.: Clothing as a cultural artifact and its current use in Art lectures at Primary Education [Thesis] Prague 2013 - Charles University, Faculty of Education, Department of Art Education, 113 p. Theoretic part of thesis deals with finding the mutual relations between the history of the 20th century clothing with wiew on combination of clothes, rituals and art. Didactic part offers a preview of current social rituals, through children's artistic perception, of which we may experience in life and personally reflect. In the practical section, through creation of a unique garment, thesis examine the possibilitie of understanding of clothing as a work of art and it's dual usage.
|
|
| |
|
| |
|
|
Automated Detection of graphic elements in EEG signal
Jančová, Ivana ; Ronzhina, Marina (referee) ; Bubník, Karel (advisor)
This thesis deals with the analysis of EEG, namely detection of graphic elements. The aim of the thesis is to describe methods suitable for detection of graphic elements and implementation of the two methods in MATLAB. The first part of the thesis describes the basics rhythms, artifacts and epileptiform transients occurring in the EEG. The second part deals with the methods of detection and their mutual comparison. The discussed methods are spectral analysis, correlation analysis, wavelet transform, cluster analysis and matched filter. Other parts of the thesis describe the database PhysioBank and implementation of the correlation analysis and matched filter. In the last part is the comparison of the success of selected methods and comparison is done by calculating sensitivity and positive predictive value.
|
|
|
Detection of Landscape in Images
Dufka, Zbyněk ; Křupka, Aleš (referee) ; Číka, Petr (advisor)
The target of this thesis is theoretical summary of methods, which are used for detection of objects in database of images. Next step is to develope own algorhytm for detection of landscape. Theoretical part describes methods Viola-Jones and HOG, which are used for detection of human faces and anomalies on radiographs. This analysis is concerned with segmentation method and algorhytm for data mining from images, which contain the landscape scenery. Appropriate method and its analysis could contribute to create and to implement into developement enviroment RapidMiner in the second part of thesis.
|
|
|
Electroencephalography
Jarošová, Veronika ; Ronzhina, Marina (referee) ; Chmelař, Milan (advisor)
This semestral paper has its aim to describe the electroencephalography. The beginning of paper is devoted to the history of electroencephalography, then there is both spontaneous and evoked brain activity described. Further, the paper deal with the electroencephalography. At the conclusion of teoretical part is described the methodology and processing of electroencephalography signal. The practical part of the work is focused on the creation of three various exercises on the epilepsy theme, reflexes and memory. Then the exercises were verified practically at fourteen volunteers. Further, in the work there is mentioned the instruction for particular measures, valuation results and its discussion.
|
guest ::
