Gets image file information
info = imfinfo(filename)
info = imfinfo(filename, 'verbose')
imfinfo to print image
            description on the screen.| Field Name | Description | 
| Filename | String containing the image file name. | 
| FileSize | Integer indicating the size of the image file in bytes. | 
| Format | "JPEG", "TIFF", "GIF", "BMP", etc. | 
| Width | Integer indicating the number of image columns in pixels. | 
| Height | Integer indicating the number of image rows in pixels. | 
| Depth | Integer indicating the number of bits per pixel. | 
| StorageType | String containing the type of color storage in the image file, which can be 'truecolor' or 'indexed'. | 
| NumberOfColors | Size of the colormap. Equals to zero for truecolor images | 
| ResolutionUnit | "inch" or "centimeters" | 
| XResolution | number  of  pixels  per ResolutionUnitin the X direction | 
| YResolution | number  of  pixels  per ResolutionUnitin the Y direction | 
imfinfo is used to get a description from image files,  without
 reading the pixels into memory. A structure  (Scilab typed list) is returned
 with the information,  which can be accessed by their names (e.g. info.Depth,
 info.FileSize, ...). The 'verbose' option causes the  description to
 be printed in an organized manner.
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