Dave Mitchell's DigitalMicrograph™ Scripting Website

// Script to create a downsampled image (thumbnail) from the passed in image

// D. R. G. Mitchell, adminnospam@dmscripting.com (remove the nospam to make this address work)

// Aug. 2009, v1.0

// version:20090815

image createthumbnail (image bigimage, number thumbx, number thumby)

{

number imagexsize, imageysize

getsize(bigimage, imagexsize, imageysize)

image thumbnail=integerimage("",2,1,thumbx, thumby)

// Only downsample if the source image is larger than the target size.

if(imagexsize>=thumbx && imageysize>=thumby)

{

number xscale=trunc(imagexsize/thumbx)

number yscale=trunc(imageysize/thumby)

thumbnail=bigimage[icol*xscale, irow*yscale]

}

else

{

showalert("Thumbnail size is greater than source image size!\nSource Image : X = "+imagexsize+" "+"Y = "+imageysize+" pixels.",2)

exit(0)

}

return thumbnail

}

// Main program starts here

// Source the frontmost image

image front:=getfrontimage()

// Get the image size

number thumbx, thumby, sizex, sizey

getsize(front, sizex, sizey)

// Ask for the thumbnail sizes in x and y. The ysize is scaled to

// have the same relative donwsample as the xsize

if(!getnumber("Enter the thumbnail X size (pixels)",32, thumbx)) exit(0)

number reducedy=round(sizey/(sizex/thumbx))

if(!getnumber("Enter the thumbnail Y size (pixels)",reducedy, thumby)) exit(0)

// Minimum size is 10 pixels

if(thumbx<10) thumbx=10

if(thumby<10) thumby=10

image thumbnail=createthumbnail(front, thumbx, thumby)

showimage (thumbnail)