Encoding of still pictures by a wavelet transform and singular value decomposition
This paper proposes a new scheme for picture compression which decomposes a picture to (3/spl times/3+1) subband pictures using the 2-D discrete wavelet transform three times, and then decomposes a picture block matrix A(16/spl times/16 pixels) of the lowest frequency subband picture to singular values and eigenvectors of AA/sup T/ and A/sup T/A and encode them by PCM. For all other subband pictures, first we encode the 0-level wavelet coefficient run-length by a modified Huffman code and then encode the non-0-level coefficients by PCM with non-linear quantizer.
Squeezing of Color Image Using Dual Tree Complex Wavelet Transform Based Preliminary Plan
In this paper, we scrutinize the role of dual tree complex wavelet transform. This Dual tree complex wavelet transform (DT-CWT) is slightly short of shift invariant and directionally selective in two or rise up dimensions.The nature of multidimensional DT-CWT is non separable & dependent on the computationally expeditious, separable filter bank(SFB).This paper explains the designing of complex wavelet transform with directional properties and use of this designed form in squeezing of image. If we take the DT-CWT transform, then many of wavelet coefficients are approximately zero and this shows the intra sub-bands dependency. We further access the performance of SPIHT coding preliminary plan for coding of those coefficients. At last, In the results of proposed preliminary plan gives higher rate of squeezing and lower mean square error(MSE) compared to plan of DWT. Dual tree complex wavelet transform-SPIHT preliminary plan outperform DWT based preliminary plan at lower bit rates.
Accurate measurements of output characteristics and detonations of motorbike high-speed racing engine and their optimization at actual atmospheric conditions and combusted mixture composition
Abstract At a motorbike high speed racing engine there is very important an output engine characteristics which depends significantly on a detonation combustion rate, atmospheric conditions and a combusted mixture composition. The combustion process has got a relevant influence on a wear degree of main engine parts or on their damage eventually. The detonation combustion rate is very important because this kind of burning can be not only destructive but a useful phenomenon, as well. If the process of detonation burning is kept on a certain level, it can help significantly to the next increasing of an engine power output. In this article there is described the measurements of output characteristics of a high-speed racing engine which were performed by means of a data-recording system and the detonation combustion was evaluated using a quantitative method. The actual values of atmospheric conditions and the mixture composition were added to the measured values. Then the obtained values are compared visually with a damage degree of an engine piston caused by the detonation burning. The result is a limit value expressed in a number of detonation units related to a run distance interval of the vehicle driven by the high-speed racing engine. In framework of this run distance interval there is the process of detonation burning profitable. As well as it increases an engine power output and together it is not destructive with regard to engine design parts.