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Pages
- Title
- Image quality measures for performance assessment of compression transforms.
- Creator
- Caimi, F. M., Schmalz, Mark S., Ritter, G. X., Harbor Branch Oceanographic Institute
- Date Issued
- 1998
- PURL
- http://purl.flvc.org/FCLA/DT/3180421
- Subject Headings
- Image compression, Image Quality
- Format
- Document (PDF)
- Title
- A novel technique for the retrieval of compressed image and video databases.
- Creator
- Saksobhavivat, Pornvit., Florida Atlantic University, Furht, Borko, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The classic methods in indexing image and video databases are either using keywords or analysis of color distribution. In the recent year, there is a new standard in image and video compression standard called JPEG and MPEG respectively. One of the basic operations of JPEG and MPEG is Discrete Cosine Transform (DCT). The human visual system is known to be very dependent on spatial frequency. The DCT has capability to provide a good approximation of the images' spatial frequency that is...
Show moreThe classic methods in indexing image and video databases are either using keywords or analysis of color distribution. In the recent year, there is a new standard in image and video compression standard called JPEG and MPEG respectively. One of the basic operations of JPEG and MPEG is Discrete Cosine Transform (DCT). The human visual system is known to be very dependent on spatial frequency. The DCT has capability to provide a good approximation of the images' spatial frequency that is sensitive to human eyes. We take this advantage of DCT in indexing image and video databases. However, the two-dimensional DCT can give us 64 coefficients per block of 8 x 8 pixels. These numbers are too many to calculate to receive fast indexing results. We use only first coefficient of DCT called DC coefficient to represent an 8 x 8 block of transformed data. This representation yields satisfactory indexing results.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/15442
- Subject Headings
- Video compression, Image compression, Indexing
- Format
- Document (PDF)
- Title
- Performance evaluation of data compression transforms for underwater imaging and object recognition.
- Creator
- Schmalz, Mark S., Ritter, G. X., Caimi, F. M., Harbor Branch Oceanographic Institute
- Date Issued
- 1997
- PURL
- http://purl.flvc.org/FCLA/DT/3183701
- Subject Headings
- Underwater imaging systems, Image compression
- Format
- Document (PDF)
- Title
- On the parallel computation of image compression transformations.
- Creator
- Caimi, F. M., Schmalz, Mark S., Ritter, G. X., Harbor Branch Oceanographic Institute
- Date Issued
- 1998
- PURL
- http://purl.flvc.org/FCLA/DT/3180419
- Subject Headings
- Image compression, Parallel computers
- Format
- Document (PDF)
- Title
- Performance analysis of compression algorithms for noisy multispectral underwater images of small targets.
- Creator
- Schmalz, Mark S., Ritter, G. X., Caimi, F. M., Harbor Branch Oceanographic Institute
- Date Issued
- 1997
- PURL
- http://purl.flvc.org/FCLA/DT/3180413
- Subject Headings
- Image compression, Underwater vision
- Format
- Document (PDF)
- Title
- Comparison and development of compression algorithms for AUV telemetry: Recent advancements.
- Creator
- Caimi, F. M., Kocak, D. M., Ritter, G. X., Schmalz, Mark S., Harbor Branch Oceanographic Institute
- Date Issued
- 1998
- PURL
- http://purl.flvc.org/FCLA/DT/3338524
- Subject Headings
- Algorithms, Telemetry, Image Quality, Image compression
- Format
- Document (PDF)
- Title
- Data compression techniques for underwater imagery.
- Creator
- Schmalz, Mark S., Ritter, G. X., Caimi, F. M., Harbor Branch Oceanographic Institute
- Date Issued
- 1996
- PURL
- http://purl.flvc.org/fau/fd/FA00007349
- Subject Headings
- Underwater imaging systems, Data Compression
- Format
- Document (PDF)
- Title
- A review of recent underwater imaging methods and advancements.
- Creator
- Caimi, F. M., Harbor Branch Oceanographic Institute
- Date Issued
- 1996
- PURL
- http://purl.flvc.org/FCLA/DT/3351972
- Subject Headings
- Underwater imaging systems, Photogrammetry, Image compression, Image processing, Review
- Format
- Document (PDF)
- Title
- DSP hardware implementation of transform-based compression algorithm for AUV telemetry.
- Creator
- Kocak, D. M., Caimi, F. M., Harbor Branch Oceanographic Institute
- Date Issued
- 1998
- PURL
- http://purl.flvc.org/FCLA/DT/3183703
- Subject Headings
- Image compression, Submersibles--Automatic control, Telemetry, Data Compression
- Format
- Document (PDF)
- Title
- An approach to image compression using three-dimensional DCT.
- Creator
- Furht, Borko, Li, Xiuqi
- Date Issued
- 2003-09-24 - 2003-09-26
- PURL
- http://purl.flvc.org/fcla/dt/358419
- Subject Headings
- Image compression., Video compression., Three-dimensional display systems.
- Format
- Document (PDF)
- Title
- Underwater laser serial imaging using compressive sensing and digital mirror device.
- Creator
- Ouyang, Bing, Dalgleish, Fraser R., Caimi, F. M., Giddings, T. E., Shirron, J. J., Vuorenkoski, Anni K., Nootz, G., Britton, W. B., Ramos, Brian
- Date Issued
- 2011
- PURL
- http://purl.flvc.org/FCLA/DT/3340793
- Subject Headings
- Underwater imaging systems, Image compression, Lasers, Signal processing
- Format
- Document (PDF)
- Title
- Application of wavelets to image and video coding.
- Creator
- Zolghadr, Esfandiar, Florida Atlantic University, Furht, Borko, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In this thesis we applied wavelet transforms to image and video coding. First, a survey of various wavelets and their features is presented, including continuous, discrete, and orthogonal wavelets. Theories and concepts underlying one and two-dimensional wavelet transforms are introduced and compared to Fourier transform and sub-band coding. The core of the thesis is the implementation of two-dimensional and three-dimensional codec architectures and their application to coding images and...
Show moreIn this thesis we applied wavelet transforms to image and video coding. First, a survey of various wavelets and their features is presented, including continuous, discrete, and orthogonal wavelets. Theories and concepts underlying one and two-dimensional wavelet transforms are introduced and compared to Fourier transform and sub-band coding. The core of the thesis is the implementation of two-dimensional and three-dimensional codec architectures and their application to coding images and videos, respectively. We studied performance of the wavelet codec by comparing it to DCT and JPEG coding techniques. We applied these techniques for compression of a variety of test images and videos. We also analyzed the adaptability and scalability of 2D and 3D codec. Experimental results, presented in the thesis, illustrate the superior performance of wavelets compared to other coding techniques.
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fcla/dt/13050
- Subject Headings
- Wavelets (Mathematics), Image compression, JPEG (Image coding standard)
- Format
- Document (PDF)
- Title
- Interactive progressive encoding system for transmission of complex images.
- Creator
- Furht, Borko, Wang, Yingli, Celli, Joseph
- Date Issued
- 1998-11
- PURL
- http://purl.flvc.org/fcla/dt/351011
- Subject Headings
- Internetworking (Telecommunication), Digital video., Image transmission., JPEG (Image coding standard), Data compression (Telecommunication) --Standards., Image compression --Standards.
- Format
- Document (PDF)
- Title
- Limits on computational precision of image compression transformations.
- Creator
- Schmalz, Mark S., Ritter, G. X., Caimi, F. M., Harbor Branch Oceanographic Institute
- Date Issued
- 1998
- PURL
- http://purl.flvc.org/FCLA/DT/3180417
- Subject Headings
- Image compression, Adaptive computing, Adaptive computation and machine learning
- Format
- Document (PDF)
- Title
- Mathematical methods for mapping image and data compression transforms to adaptive computing systems.
- Creator
- Schmalz, Mark S., Witter, G. S., Caimi, F. M., Harbor Branch Oceanographic Institute
- Date Issued
- 1998
- PURL
- http://purl.flvc.org/FCLA/DT/3183705
- Subject Headings
- Image compression, Adaptive computing systems, Underwater acoustic telemetry
- Format
- Document (PDF)
- Title
- Densely-centered uniform P-search: A fast motion estimation algorithm.
- Creator
- Greenberg, Joshua H., Florida Atlantic University, Furht, Borko
- Abstract/Description
-
Video compression technology promises to be the key to the transmission of motion video. A number of techniques have been introduced in the past few years, particularly that developed by the Motion Picture Experts Group (MPEG). The MPEG algorithm uses Motion Estimation to reduce the amount of data that is stored for each frame. Motion Estimation uses a reference frame as a codebook for a modified Vector Quantization process. While an exhaustive search for Motion Estimation Vectors is time...
Show moreVideo compression technology promises to be the key to the transmission of motion video. A number of techniques have been introduced in the past few years, particularly that developed by the Motion Picture Experts Group (MPEG). The MPEG algorithm uses Motion Estimation to reduce the amount of data that is stored for each frame. Motion Estimation uses a reference frame as a codebook for a modified Vector Quantization process. While an exhaustive search for Motion Estimation Vectors is time-consuming, various fast search algorithms have been developed. These techniques are surveyed, and the theoretical framework for a new search algorithm is developed: Densely-Centered Uniform P-Search. The time complexity of Densely-Centered Uniform P-Search is comparable to other popular Motion Estimation techniques, and shows superior results on a variety of motion video sources.
Show less - Date Issued
- 1996
- PURL
- http://purl.flvc.org/fcla/dt/15286
- Subject Headings
- Image processing--Digital techniques, Data compression (Telecommunication)
- Format
- Document (PDF)
- Title
- A novel DSP scheme for image compression and HDTV transmission.
- Creator
- Dong, Xu., Florida Atlantic University, Sudhakar, Raghavan, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The main objective of the research is to develop computationally efficient hybrid coding schemes for the low bit implementations of image frames and image sequences. The basic fractal block coding can compress a relatively low resolution image efficiently without blocky artifacts, but it does not converge well at the high frequency edges. This research proposes a hybrid multi-resolution scheme which combines the advantages of fractal and DCT coding schemes. The fractal coding is applied to...
Show moreThe main objective of the research is to develop computationally efficient hybrid coding schemes for the low bit implementations of image frames and image sequences. The basic fractal block coding can compress a relatively low resolution image efficiently without blocky artifacts, but it does not converge well at the high frequency edges. This research proposes a hybrid multi-resolution scheme which combines the advantages of fractal and DCT coding schemes. The fractal coding is applied to get a lower resolution, quarter size output image and DCT is then used to encode the error residual between original full bandwidth image signal and the fractal decoded image signal. At the decoder side, the full resolution, full size reproduced image is generated by adding decoded error image to the decoded fractal image. Also, the lower resolution, quarter size output image is automatically given by the iteration function scheme without having to spend extra effort. Other advantages of the scheme are that the high resolution layer is generated by error image which covers the bandwidth loss of the lower resolution layer as well as the coding error of the lower resolution layer, and that it does not need a sophisticated classification procedure. A series of computer simulation experiments are conducted and their results are presented to illustrate the merit of the scheme. The hybrid fractal coding method is then extended to process motion sequences as well. A new scheme is proposed for motion vector detection and motion compensation, by judiciously combining the techniques of fractal compression and block matching. The advantage of this scheme is that it improves the performance of the motion compensation, while keeping the overall computational complexity low for each frame. The simulation results on realistic video conference image sequences support the superiority of the proposed method in terms of reproduced picture quality and compression ratio.
Show less - Date Issued
- 1995
- PURL
- http://purl.flvc.org/fcla/dt/12407
- Subject Headings
- Hybrid integrated circuits, Image compression, Fractals, Image processing--Digital techniques, High definition television
- Format
- Document (PDF)
- Title
- Subband coding of images using binomial QMF and vector quantization.
- Creator
- Rajamani, Kannan., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis presents an image coding system using binomial QMF based subband decomposition and vector quantisation. An attempt was made to compress a still image of size 256 x 256 represented at a resolution of 8 bits/pixel to a bit rate of 0.5 bits/pixel using 16 channel subband decomposition with binomial QMFs and coding the subbands using a full search LBG Vector Quantizer (VQ). Simulations were done on SUN work station and the quality of the image was evaluated by computing the Signal to...
Show moreThis thesis presents an image coding system using binomial QMF based subband decomposition and vector quantisation. An attempt was made to compress a still image of size 256 x 256 represented at a resolution of 8 bits/pixel to a bit rate of 0.5 bits/pixel using 16 channel subband decomposition with binomial QMFs and coding the subbands using a full search LBG Vector Quantizer (VQ). Simulations were done on SUN work station and the quality of the image was evaluated by computing the Signal to Noise Ratio (SNR) between the original image and the reconstructed image.
Show less - Date Issued
- 1995
- PURL
- http://purl.flvc.org/fcla/dt/15203
- Subject Headings
- Image compression--Digital techniques, Image processing--Digital techniques, Image transmission--Digital techniques, Coding theory, Vector fields
- Format
- Document (PDF)
- Title
- HEVC optimization in mobile environments.
- Creator
- Garcia, Ray, Kalva, Hari, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Recently, multimedia applications and their use have grown dramatically in popularity in strong part due to mobile device adoption by the consumer market. Applications, such as video conferencing, have gained popularity. These applications and others have a strong video component that uses the mobile device’s resources. These resources include processing time, network bandwidth, memory use, and battery life. The goal is to reduce the need of these resources by reducing the complexity of the...
Show moreRecently, multimedia applications and their use have grown dramatically in popularity in strong part due to mobile device adoption by the consumer market. Applications, such as video conferencing, have gained popularity. These applications and others have a strong video component that uses the mobile device’s resources. These resources include processing time, network bandwidth, memory use, and battery life. The goal is to reduce the need of these resources by reducing the complexity of the coding process. Mobile devices offer unique characteristics that can be exploited for optimizing video codecs. The combination of small display size, video resolution, and human vision factors, such as acuity, allow encoder optimizations that will not (or minimally) impact subjective quality. The focus of this dissertation is optimizing video services in mobile environments. Industry has begun migrating from H.264 video coding to a more resource intensive but compression efficient High Efficiency Video Coding (HEVC). However, there has been no proper evaluation and optimization of HEVC for mobile environments. Subjective quality evaluations were performed to assess relative quality between H.264 and HEVC. This will allow for better use of device resources and migration to new codecs where it is most useful. Complexity of HEVC is a significant barrier to adoption on mobile devices and complexity reduction methods are necessary. Optimal use of encoding options is needed to maximize quality and compression while minimizing encoding time. Methods for optimizing coding mode selection for HEVC were developed. Complexity of HEVC encoding can be further reduced by exploiting the mismatch between the resolution of the video, resolution of the mobile display, and the ability of the human eyes to acquire and process video under these conditions. The perceptual optimizations developed in this dissertation use the properties of spatial (visual acuity) and temporal information processing (motion perception) to reduce the complexity of HEVC encoding. A unique feature of the proposed methods is that they reduce encoding complexity and encoding time. The proposed HEVC encoder optimization methods reduced encoding time by 21.7% and bitrate by 13.4% with insignificant impact on subjective quality evaluations. These methods can easily be implemented today within HEVC.
Show less - Date Issued
- 2014
- PURL
- http://purl.flvc.org/fau/fd/FA00004112
- Subject Headings
- Coding theory, Digital coding -- Data processing, Image processing -- Digital techniques, Multimedia systems, Video compression
- Format
- Document (PDF)
- Title
- Methods and Algorithms for Human Detection in Video Sequences.
- Creator
- Pertuz, Carlos, Marques, Oge, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Lower prices of video sensors, security concerns and the need for better and faster algorithms to extract high level information from video sequences are all factors which have stimulated research in the area of automated video surveillance systems. In the context of security the analysis of human interrelations and their environment provides hints to proactively identify anomalous behavior. However, human detection is a necessary component in systems where the automatic extraction of higher...
Show moreLower prices of video sensors, security concerns and the need for better and faster algorithms to extract high level information from video sequences are all factors which have stimulated research in the area of automated video surveillance systems. In the context of security the analysis of human interrelations and their environment provides hints to proactively identify anomalous behavior. However, human detection is a necessary component in systems where the automatic extraction of higher level information, such as recognizing individuals' activities, is required. The human detection problem is one of classification. In general, motion, appearance and shape are the classification approaches a system can employ to perform human detection. Techniques representative of these approaches, such us periodic motion detection, skin color detection and MPEG-7 shape descriptors are implemented in this work. An infrastructure that allows data collection for such techniques was also implemented.
Show less - Date Issued
- 2007
- PURL
- http://purl.flvc.org/fau/fd/FA00012538
- Subject Headings
- MPEG (Video coding standard), Image processing--Digital techniques, Form perception, Computer algorithms, Video compression
- Format
- Document (PDF)