When MRIcro converts medical images (DICOM, GE, Elscint, etc) to Analyze format, is any image data lost?
MRIcro’s image converion is lossless. For example, DICOM 8-bit images (with values 0..255) will be saved as Analyze 8-bit images, and DICOM 16-bit images (with values ranging from -32768..32767) will be saved as Analyze 16-bit images. Therefore, the raw data is identical. However, it is worth noting that the headers of medical images often include a function to calibrate the raw data. Consider a 8-bit DICOM image with voxel intensities ranging from 0..200 (see figure below). The header might specify a function such as “Y = (X*0.4)+20”. In this case, a voxel with a raw value of 200 will have a scaled value of 100 [=(200*0.4)+20]. In this example, the header specifies a slope (0.4) and a X-intercept (20). While DICOM headers can specify both a slope and an intercept, SPM99/MRIcro (pre-1.36) headers can only specify a slope (this is the ‘scale’ value in MRIcro’s “Header Information” panel). Therefore, if the hypothetical DICOM images were converted to Analyze format, the scaling transform
