X ray imaging

B-Scan X-Rays Images Segmentation Using Co-Occurrence Matrix. 

Manual thresholding by detecting peaks of matrix diagonal (4) to segment X-Rays images. 

We apply also this tool to X-rays images that are currently increasingly studied. 

The X-ray tube generates an X-ray image of the workpiece via central projection. 

An X-ray image of a test object is converted by a X-ray TV unit (4), and complete video-signal from it is supplied to specialized computer (5). For conversion of X-ray images series X-ray vidicons LI-444 and LI-473 can be used or experimental X-ray vidicons of the same dimensions with a Be input window [2] sensitive to soft X-radiation developed in Introscopy Institute. >. ... 

Application of experimental devices allows to perform NDT of products, made out of materials of low density (Al-Mg - alloys, Be, plastics) with high defectoscopic sensitivity up to 0,5 %. Inch-size X-ray vidicons used complete with microfocal X-ray tubes and X-ray image enlargement method allow to obtain resolution up to SO pairs of lines per mm. 

Real Time X-Ray images are stored on CD ROM/XA. Compared to film the volume for a storage is reduced by a factor 50. Retrieving is easy since information of the location is given in the directory of the diskette. Normally the directory name is the shop order and the file name is the serial number of the part. The directory and file names can be customised. 

For examination of X-Ray images the customer needs standard hard- and software as given in table 4 and 5. As mentioned before the directory can be customised to specification defined by the customer. 

Figure 1 X-ray imaging system with calibration body and test sample...

To describe the X-ray imaging system the projection of 3D object points onto the 2D image plane, and nonlinear distortions inherent in the image detector system have to, be modelled. A parametric camera model based on a simple pinhole model to describe the projection in combination with a polynomal model of the nonlinear distortions is used to describe the X-ray imaging system. The parameters of the model are estimated using a two step approach. First the distortion parameters for fixed source and detector positions are calculated without any knowledge of the projection parameters. In a second step, the projection parameters are calculated for each image taken with the same source and detector positions but with different sample positions. 

Doering, E.R. Basart,. I.P. Gray,. I.N. Three-dimensional flaw reconstruction and dimensional analysis using a real-time X-ray imaging system. NDT-I-E International, Vol. 26(1), 1993, pp. 7-17. 

This study describes one stage of a soft tool realisation, which facilitate and improve the task of the expert for x-ray image interpretation and decision-making. We are interested by tbe first four stages of this flow chart. 

This focal spot diameter is very much smaller than the spots of conventional X-ray tubes. The goodness of a X-ray image is influenced by contrast and sharpness. Caused by the almost punctual point of origin of the X-rays, a low geometrical unsharpness according to equation 1 is reached. 

Equations 1 and 2 shows that the distance b between the radiation source and the object has big influence on the X-ray image [8]. Therefore you have to find a compromise between a small geometrical unsharpness and a sufficient high magnification to archive an optimal... 

BE-1042 Nex X ray imaging sensors. Mr. C. Frdjdh Resam Medical Syatema AB... 

Whereas scintillation screens can be used to directly view x-rays passing through the body, the dose to a patient is too high. Instead, scintillation screens are combined with video cameras or electronic intensifier tubes and video cameras. This detection scheme is used in digital radiography where digital x-ray images are recorded, and fluoroscopy where temporal processes are to be followed. 

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