In the age of information and communication technology (ICT), the requirements of multimedia image transmission are essential. image compression (source coding) has provided significant improvements for communication ...
详细信息
In the age of information and communication technology (ICT), the requirements of multimedia image transmission are essential. image compression (source coding) has provided significant improvements for communication bandwidth, and transmission cost and data rate. the objective of the paper is to develop new techniques for strengthening the compression of still images. the features of the proposed algorithm include: (i) a wavelet transform engine, which provides a better image compression rate and visual quality as compared to DCT-based systems (JPEG); (ii) zero-path which exploits the cross-scale self-similarity of wavelet coefficients and thus provides zero-path compression; (iii) the absence of side information (significant map) for coding and decoding of zero-tree structure hence reduces the data bits for significant map symbolic coding; (iv) adaptive arithmetic entropy coding provides further compression on generating variable-length codewords. Experimental results show that the proposed algorithm outperforms both JPEG and the EZW (embedded zerotree wavelet) algorithms in terms of peak signal-to-noise ratio (PSNR), data compression bit-rate (bpp), and also human visual perception.
Entropy coding algorithms assign variable length codes to the input data (symbols) based on their statistical properties. those techniques are used in both lossless and lossy compression systems. this article presents...
详细信息
Entropy coding algorithms assign variable length codes to the input data (symbols) based on their statistical properties. those techniques are used in both lossless and lossy compression systems. this article presents scaling and residual mapping parameters in coding schemes and their effect on compression of images. In our experiments these entropy coding techniques have been incorporated in simple DPCM based lossless compressor.
Lossless fractal imagecoding (LFIC) is a new method to code images. the significant property of this method is that it is the first simple fractal imagecoding method that can regenerate images without data loss (los...
详细信息
Lossless fractal imagecoding (LFIC) is a new method to code images. the significant property of this method is that it is the first simple fractal imagecoding method that can regenerate images without data loss (lossless). the method, different from the other fractal image compression, needs no search for the matched domain-range. therefore, the coding time of this method is also very fast compared withthe other fractal image compression methods.
In this paper, a new lossless method for real time compression of still images in the field of the artificial vision, is presented. the proposed method is based on a new focus which incorporates the simultaneous execu...
详细信息
In this paper, a new lossless method for real time compression of still images in the field of the artificial vision, is presented. the proposed method is based on a new focus which incorporates the simultaneous execution of the acquisition and compression process of an image. the method consists of three processes. In the first one, a linear camera captures a line which is stored in memory. In the next step, the compression process of this line is executed at the same time as the acquisition process reads the next line. the process is repeated downwards starting from the upper line of the image. the novelty and main contribution of this method is in the compression process. A new coding algorithm is formulated and developed. the proposed method guarantees a ratio of compression of 3:1 with high probability and a real time execution.
In digital video coding, the 2-D block-based discrete cosine transform (DCT) has been widely used, combined withthe quantization techniques of DCT coefficients, for the purpose of compression of video data. Video com...
详细信息
In digital video coding, the 2-D block-based discrete cosine transform (DCT) has been widely used, combined withthe quantization techniques of DCT coefficients, for the purpose of compression of video data. Video compression algorithms using this block-based transform coding method cause the blocking and ringing artifacts in the reconstructed images of a video sequence. In this paper, we propose the efficient post-processing algorithm for coded video sequence, where the ringing effects near sharp edges are smoothed out and the blocking effects are removed without blurring the edge regions at the decoder. the simulation examples of processing images coded by MPEG-2 are presented to demonstrate that a significant improvement has been achieved.
this conference proceedings deals with: H.264 video coding standard; MPEG-4; Croatian digital video broadcasting; multimedia streaming networks; digital signal processing; imagedata processing; ultrasonic imaging; co...
this conference proceedings deals with: H.264 video coding standard; MPEG-4; Croatian digital video broadcasting; multimedia streaming networks; digital signal processing; imagedata processing; ultrasonic imaging; color correlation; edge-preserving regularization; image reconstruction; computer vision; 3D-DCT compression; lossless fractal imagecoding; post-processing algorithm; video processing; mammogram; image registration; gray-scale images; hotelling transform; photon-limited images; steerable pyramids; image retrieval; edge detection technique; querying; robust image matching algorithm; local expert networks; content-based mesh generation algorithm; texture recognition; audio classification; stereo image compression; mitochondrial genomic signals; fast Fourier transform; Hough transform; weighted vector median optimization; entropy vector filters; group signature scheme; impulsive noise reduction technique; multiprocessors systems; color image enhancement; nonparametric density estimation; video coding; programmable media processor; PDA; digital video software encoder; hybrid DWT-SVD imagecoding system; wavelet transform; error-resilient video codec; adaptive data mapping; MIMO systems; DSL communication; pose invariant face detection; 3D face recognition; MCM; facial recognition system; radar objection identification; image segmentation tool; maritime images; world wide web; video indexing; ridge polynomial network; pattern recognition; hypergraph representation; delay jitter analysis; network latency; broadband communication network; predictive speech coding; noisy medical audio signal; context dependent viseme model; voice driven animation; forward masking phenomenon; concatenative speech synthesis; data hiding; blind watermarking; T-codes; Internet; bluetooth; WPAN; wireless ad hoc networks; direct spread sequence mobile communication system; virtual private networks; CATV broadband technologies.
Measurement of image quality is crucial for many image processing algorithms. In this paper, a "no-reference" picture quality evaluation is proposed. We use watermarking as a tool for evaluating quality. We ...
详细信息
Measurement of image quality is crucial for many image processing algorithms. In this paper, a "no-reference" picture quality evaluation is proposed. We use watermarking as a tool for evaluating quality. We embed, in an image, a watermark. Measures are computed between original and extracted watermarks instead of image to evaluate picture quality between the original image and the degraded one. Experimental results show the efficiency of the given approach in the case of JPEG compression.
Embedding watermark in compressed video is a challenging problem, and moreover transcodingthe watermarked video due to bandwidth requirement makes the watermark more difficult to survive. As we know, transcoding some...
详细信息
Embedding watermark in compressed video is a challenging problem, and moreover transcodingthe watermarked video due to bandwidth requirement makes the watermark more difficult to survive. As we know, transcoding sometimes involves numerical process as well as geometrical process, such as aspect ratio changing. In this paper, synthetical techniques including redundant embedding and scene-based embedding are presented to increase the watermark robustness against video transcoding, especially heterogeneous transcoding. Experimental results show that the proposed strategies are perfect in solving the attack.
A unified approach to the fast computation of evenly and oddly stacked modified discrete cosine transform (MDCT) and modified discrete sine transform (MDST) is presented. Although the evenly and oddly stacked MDCT/MDS...
详细信息
A unified approach to the fast computation of evenly and oddly stacked modified discrete cosine transform (MDCT) and modified discrete sine transform (MDST) is presented. Although the evenly and oddly stacked MDCT/MDST are quite different filter banks, there exists an intimate relation between them, and consequently, the efficient oddly stacked MDCT/MDST computation can be realized via the evenly stacked MDCT/MDST and vice versa only by simple preprocessing and postprocessing of input and output data sequences. In particular, it is shown that the transposed evenly and oddly stacked MDCT and MDST matrices are actually the generalized inverses or pseudoinverses of their corresponding forward transform matrices.
the adaptive data mapping of wavelet compressed images in multiple input multiple output (MIMO) wireless communication systems is proposed and analyzed. image compression methods based on wavelet transform allow image...
详细信息
the adaptive data mapping of wavelet compressed images in multiple input multiple output (MIMO) wireless communication systems is proposed and analyzed. image compression methods based on wavelet transform allow image decomposition in blocks, representing signal frequency bands at different resolutions. Blocks representing low frequencies are very important for visual image quality, while the highest frequency blocks, even lost, have almost no impact on image quality. MIMO systems offer parallel subchannels with different quality. Mapping more important data to higher quality subchannels improves the image quality. the results obtained by analog devices wavelet algorithm, implemented in a single chip ADV601, used in the MIMO system with four transmit and four receive antennas, show that the adaptive data mapping approach improves the peak signal to noise ratio (PSNR) up to 8 dB in comparison to standard data mapping.
暂无评论