Fractures of bone are a common affliction. In most developed countries the number of fractures associated with age-related bone loss is increasing rapidly. Each year many fractures are missed during x-ray diagnosis, resulting in ineffective patient management and expensive litigation. From both an orthopaedic and radiologic point of view, the fully automatic detection and classification of fractures in long-bones is an important but difficult problem. In this paper, a fully automated method of detecting fractures in the diaphysis of a long-bone is described. X-rays are very difficult to process automatically, so to extract the required information a non-linear anisotropic diffusion method, the Affine Morphological Scale Space, was implemented to smooth the image without losing information about the location of boundaries within the image. Next, an iterative peak detection algorithm is used to accurately locate the bone centreline and articular surfaces. A method based on orthogonal projections calculated from a modified Hough transform is used to automatically locate the long-bone diaphysis. At this point, our algorithm accurately localises the area of the fracture, and would allow further image registration if necessary. Finally, a gradient-based algorithm is used to detect fractures present in the region of interest. The magnitude and direction of the gradient are combined to produce a measure of the likelyhood of the presence of a fracture. A library of long-bone fracture images was created. Experimental tests performed on a series of x-ray images show that the method is capable of accurately segmenting the diaphysis from the epiphyses, and is also able to detect many mid-shaft fractures of long-bones.
JPEG2000 is the newest international standard to be produced by the Joint Photographic Experts Group (JPEG) and it has recently been published as an International Standards Organization/IEC standard and as an ITU-T recommendation. It complements most of the currently used standards including the original JPEG, usually with superior compression for the same image quality, or alternatively with superior image quality for the same bit rate. The algorithm uses the wavelet transform followed by an embedded block coder incorporating the MQ arithmetic coder. In this article we give a novel hardware architecture for the block coder and MQ coder as used in the JPEG2000 standard. Together with appropriate software, this design enables a high performance system-on-chip solution for JPEG2000 image compression. We have included sufficient introductory material to interest readers unfamiliar with either JPEG2000 or hardware design.
In this note we give a new architecture for the bi-orthogonal wavelet transform. The basis of our approach is a new convolver circuit that generates low and high pass values simultaneously in the forward transform, and combines low and high pass values in the inverse transform to produce even and odd data values. This is possible because of the symmetry of the bi-orthogonal wavelet coefficients and because the bi-orthogonal wavelet transform preserves the number of input data samples. The results are optimal in the sense of the number of multipliers used. The architecture given here is more efficient than lifting, for example in the case of the Daubechies 9-7 wavelet, lifting requires 6 multiplications per transformed (H, G) pair, while this method uses only 5. Note that the designs given here are fully pipelined and so are suitable for high-speed or low-power implementation.