4.8.4 Registering One Image to Another Image


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4.8.4 Registering One Image to Another Image

Once the image coordinates are known for the non-SXT image(s), you can call the routine COAL_IMAGE which will co-align one image to another. The following assumptions are made for the sample calling sequences below.
IDL> pix2 = 3.97 ; pixel size of non-SXT image

IDL> pix1 = gt_pix_size(index) ; SXT image pixel size

IDL> corner1 = gt_corner(index, /from_sc) ; the SXT corner

To convert the non-SXT image to the resolution and align it to the SXT image you would use the first command below, and you can optionally compare the newly aligned images with the second command.
IDL> out1 = coal_image(img, corner2, corner1, [256,256], mag=pix2/pix1)
 
IDL> flash_comp, out1, data

The following are the commands to convert the SXT image to the resolution of the non-SXT image, and align it to the non-SXT image:
IDL> out2 = coal_image(data, index, corner2, [512,512], mag=pix1/pix2)
 
IDL> flash_comp, out2, img

There is an optional keyword angle which will roll one image relative to the other if the angle is known. See the description of COAL_IMAGE in the reference guide and the program header for more information.


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