Medical images adaptive compression for transmission and archiving. Application to cerebral angiography

Image compression with loss presents a major interest or profit for archiving and image transmission. Many methods are used in this field. The most useful is based on the discrete cosine transform DCT. It then, represents the core of the JPEG´s norm on the compression of fixed images. Medical structures involve an important volume of administrative and medical information where imagery could be high lighted. But the quantity of information represented by images cause serious problems. Our task deals with algorithmic aspects looking for compression technique adapted to different modalities of medical imagery and on the validity of images. A statistical study has been extensively done so as to determine the laws which follow the coefficients resulted from DCT. Results which are already obtained were used to work with the compression. The validity of diagnostic quality of medical images is largely based on an assessment made by a group of medical experts. We finally come to observe that the diagnostic quality of the image is kept. Globally, the results are very encouraging and positive they eventually show that compression is acceptable and largely useful in medical work.