Now showing items 1-20 of 39

    • A 2-D orientation-adaptive prediction filter in lifting structures for image coding 

      Gerek, Ö. N.; Çetin, A. Enis (Institute of Electrical and Electronics Engineers, 2006)
      Lifting-style implementations of wavelets are widely used in image coders. A two-dimensional (2-D) edge adaptive lifting structure, which is similar to Daubechies 5/3 wavelet, is presented. The 2-D prediction filter predicts ...
    • Adaptive polyphase subband decomposition structures for image compression 

      Gerek, Ö. N.; Çetin, A. Enis (IEEE, 2000)
      Subband decomposition techniques have been extensively used for data coding and analysis. In most filter banks, the goal is to obtain subsampled signals corresponding to different spectral regions of the original data. ...
    • Binary morphological subband decomposition for image coding 

      Gürcan, Metin Nafi; Gerek, Ömer Nezih; Çetin, A. Enis (IEEE, 1996)
      In this paper a binary waveform coding method based on morphological subband decomposition coupled with embedded zero-tree and entropy coding is described. This method can be utilized in text compression or bit-plane coding ...
    • Block wavelet transforms for image coding 

      Çetin, A. Enis; Gerek, Ö. N.; Ulukuş, Ş. (IEEE, 1993)
      In this paper, a new class of block transforms is presented. These transforms are constructed from subband decomposition filter banks corresponding to regular wavelets. New transforms are compared to the discrete cosine ...
    • Coding of fingerprint images using binary subband decomposition and vector quantization 

      Gerek, Ömer N.; Çetin, A. Enis (SPIE, 1998-01)
      In this paper, compression of binary digital fingerprint images is considered. High compression ratios for fingerprint images is essential for handling huge amount of images in databases. In our method, the fingerprint ...
    • Compression of images in CFA format 

      Cüce, Halil İbrahim; Çetin, A. Enis; Davey, M. K. (IEEE, 2006)
      In this paper, images in Color Filter Array (CFA) format are compressed without converting them to full-RGB color images. Green pixels are extracted from the CFA image data and placed in a rectangular array, and compressed ...
    • DCT coding of nonrectangularly sampled images 

      Gündüzhan, E.; Çetin, A. Enis; Tekalp, A. M. (IEEE, 1994)
      Discrete cosine transform (DCT) coding is widely used for compression of rectangularly sampled images. In this letter, we address efficient DCT coding of nonrectangularly sampled images. To this effect, we discuss an ...
    • Error resilient layered stereoscopic video streaming 

      Tan, Ahmet Serdar; Aksay, A.; Bilen, Ç.; Bozdağı-Akar, G.; Arıkan, Erdal (IEEE, 2007)
      In this paper, error resilient stereoscopic video streaming problem is addressed. Two different Forward Error Correction (FEC) codes namely Systematic LT and RS codes are utilized to protect the stereoscopic video data ...
    • Estimation of depth fields suitable for video compression based on 3-D structure and motion of objects 

      Alatan, A. A.; Onural, L. (Institute of Electrical and Electronics Engineers, 1998-06)
      Intensity prediction along motion trajectories removes temporal redundancy considerably in video compression algorithms. In three-dimensional (3-D) object-based video coding, both 3-D motion and depth values are required ...
    • Haber videolarında nesne tanıma ve otomatik etiketleme 

      Baştan, Muhammet; Duygulu, Pınar (IEEE, 2006-04)
      We propose a new approach to object recognition problem motivated by the availability of large annotated image and video collections. Similar to translation from one language to another, this approach considers the object ...
    • Impact of scalability in video transmission in promotion-capable differentiated services networks 

      Gürses, E.; Akar, G. B.; Akar, Nail (IEEE, 2002-09)
      Transmission of high quality video over the Internet faces many challenges including unpredictable packet loss characteristics of the current Internet and the heterogeneity of receivers in terms of their bandwidth and ...
    • An improvement to MBASIC algorithm for 3-D motion and depth estimation 

      Bozdağı, G.; Tekalp, A. M.; Onural, L. (IEEE, 1994)
      In model-based coding of facial images, the accuracy of motion and depth parameter estimates strongly affects the coding efficiency. MBASIC is a simple and effective iterative algorithm (recently proposed by Aizawa et al.) ...
    • Iterative technique for 3-D motion estimation in videophone applications 

      Bozdağı, Gözde; Tekalp, A. M.; Onural, Levent (IEEE, 1994-04)
      In object based coding of facial images, the accuracy of motion and depth parameter estimates strongly affects the coding efficiency. We propose an improved algorithm based on stochastic relaxation for 3-D motion and depth ...
    • Joint estimation and optimum encoding of depth field for 3-D object-based video coding 

      Alatan, A. Aydın; Onural, Levent (IEEE, 1996-09)
      3-D motion models can be used to remove temporal redundancy between image frames. For efficient encoding using 3-D motion information, apart from the 3-D motion parameters, a dense depth field must also be encoded to achieve ...
    • Linear and nonlinear temporal prediction employing lifting structures for scalable video coding 

      Töreyin, B. Uğur; Trocan, M.; Pesquet-Popescu, B.; Çetin, A. Enis (IEEE, 2006-09)
      Scalable 3D video codecs based on wavelet lifting structures have attracted recently a lot of attention, due to their compression performance comparable with that of state-of-art hybrid codecs. In this work, we propose a ...
    • Linear/nonlinear adaptive polyphase subband decomposition structures for image compression 

      Gerek, Ömer N.; Çetin, A. Enis (IEEE, 1998-05)
      Subband decomposition techniques have been extensively used for data coding and analysis. In most filter banks, the goal is to obtain subsampled signals corresponding to different spectral bands of the original data. ...
    • LMS based adaptive prediction for scalable video coding 

      Töreyin, B. Uğur; Trocan, M.; Pesquet-Popescu, B.; Çetin, A. Enis (IEEE, 2006-05)
      3D video codecs have attracted recently a lot of attention, due to their compression performance comparable with that of state-of-art hybrid codecs and due to their scalability features. In this work, we propose a least ...
    • Lossless image compression by LMS adaptive filter banks 

      Öktem, R.; Çetin, A. Enis; Gerek, O. N.; Öktem, L.; Egiazarian, K. (Elsevier, 2001)
      A lossless image compression algorithm based on adaptive subband decomposition is proposed. The subband decomposition is achieved by a two-channel LMS adaptive filter bank. The resulting coefficients are lossy coded first, ...
    • Lossless image compression using an edge adapted lifting predictor 

      Gerek, Ö. N.; Çetin, A .Enis (IEEE, 2005-09)
      We present a novel and computationally simple prediction stage in a Daubechies 5/3 - like lifting structure for lossless image compression. In the 5/3 wavelet, the prediction filter predicts the value of an odd-indexed ...
    • Morphological subband decomposition structure using GF(N) arithmetic 

      Gürcan, Metin Nafi; Çetin, A. Enis; Gerek, Ömer, N. (IEEE, 1996-09)
      Linear filter banks with critical subsampling and perfect reconstruction (PR) property have received much interest and found numerous applications in signal and image processing. Recently, nonlinear filter bank structures ...