X-Git-Url: http://git.kpe.io/?a=blobdiff_plain;f=dof.lisp;h=f1cd7b245a71b07bd95e1afdcfcf81a5bc15bcce;hb=6290486a001d80c01676dfd9c2ac053cb4bc1871;hp=ee9250a745c0d613716cdc405e798f8a8e191019;hpb=4860883d5bf05e9e7c83d4f16a001e4edd1d1cb2;p=cl-photo.git

diff --git a/dof.lisp b/dof.lisp
index ee9250a..f1cd7b2 100644
--- a/dof.lisp
+++ b/dof.lisp
@@ -19,24 +19,34 @@
 
 (in-package #:photo)
 
-(defun coc (imager-size &key (lpm 5) (minimum-distance 250) 
+(defun sort-size (size)
+  "Returns a cons pair with the smaller size first."
+  (if (>= (car size) (cdr size))
+      (cons (cdr size) (car size))
+      (cons (car size) (cdr size))))
+
+(defun print-magnification (imager-size print-size)
+  "Returns the magnification required between an imager and print sizes
+while taking crop into consideration."
+  (setf imager-size (sort-size imager-size))
+  (setf print-size (sort-size print-size))
+  (float (max (/ (car print-size) (car imager-size))
+              (/ (cdr print-size) (cdr print-size)))))
+
+(defun coc (imager-size &key (lpm 5) (minimum-distance 250)
                    (viewing-distance 250)
                    (print-size (output-dimensions :8x10in)))
-  "Returns circle of confusion in mm and print magnification for a format. 
+  "Returns circle of confusion in mm and print magnification for a format.
 Default resolving power is 5 lpm at 25cm."
+  (let* ((magnification (print-magnification imager-size print-size))
+         (resolution-factor (/ (* magnification lpm minimum-distance) viewing-distance))
+         (coc (/ 1.0d0 resolution-factor)))
+    (values coc magnification)))
 
-  (let* ((imager-diagonal (diagonal (car imager-size) (cdr imager-size)))
-         (print-diagonal (diagonal (car print-size) (cdr print-size)))
-         (resolution-factor (/ (* lpm print-diagonal minimum-distance)
-                               (* imager-diagonal viewing-distance)))
-         (coc (/ 1.0d0 resolution-factor))
-         (print-magnification (/ print-diagonal imager-diagonal)))
-    (values coc print-magnification)))
-
-(defun coc-format (format &key (lpm 5) (minimum-distance 250) 
+(defun coc-format (format &key (lpm 5) (minimum-distance 250)
                           (viewing-distance 250)
                           (print-size (output-dimensions :8x10in)))
-  "Returns circle of confusion in mm and print magnification for a format. 
+  "Returns circle of confusion in mm and print magnification for a format.
 Default resolving power is 5 lpm at 25cm."
 
   (let* ((format-size (imager-dimensions format))
@@ -52,9 +62,9 @@ Default resolving power is 5 lpm at 25cm."
   "Returns lpm and circle of confusion based on pixel size."
   (when (and (consp imager) (consp pixels))
     (let ((coc-w (float (* 2 (/ (car imager) (car pixels)))))
-	  (coc-h (float (* 2 (/ (cdr imager) (cdr pixels))))))
+          (coc-h (float (* 2 (/ (cdr imager) (cdr pixels))))))
     (values coc-w coc-h (/ 1. coc-w) (/ 1. coc-h)))))
-  
+
 (defun coc-pixels-format (format)
   "Returns circle of confusion based on pixel size."
   (coc-pixels (imager-dimensions format) (pixel-dimensions format)))
@@ -78,7 +88,7 @@ Default resolving power is 5 lpm at 25cm."
 Six values are returned:
 near point, far point, total dof, magnification, blur size at infinity (mm).
 Circle of confusion can either be a number or keyword designating format."
-  (let* ((aperture (/ focal-length f-stop)) 
+  (let* ((aperture (/ focal-length f-stop))
          (numerator-1 (* (- pupil-factor 1) (- distance focal-length)
                          coc focal-length))
          (numerator-2 (* pupil-factor aperture focal-length distance))
@@ -114,10 +124,10 @@ Pupil factor is the ratio of the exit to enterance pupil diameters."
 
 (defun dof (focal-length f-stop distance coc &key (units :mm) (pupil-factor 1))
   "Returns the Depth of Field.
-Input: FOCAL-LENGTH, F-STOP, DISTANCE, CIRCLE-OF-CONFUSION. 
+Input: FOCAL-LENGTH, F-STOP, DISTANCE, CIRCLE-OF-CONFUSION.
 Output: NEAR-POINT, FAR-POINT, TOTAL-DOF, MAGNIFICATION, BLUR-SIZE-OF-INFINITY-POINT-IN-MM."
   (multiple-value-bind (near-point far-point total-dof mag blur)
-      (dof-mm focal-length f-stop (length->mm distance units) coc 
+      (dof-mm focal-length f-stop (length->mm distance units) coc
               :pupil-factor pupil-factor)
     (values (mm->length near-point units)
             (mm->length far-point units)
@@ -133,5 +143,3 @@ Output: NEAR-POINT, FAR-POINT, TOTAL-DOF, MAGNIFICATION, BLUR-SIZE-OF-INFINITY-P
 (defun mtf-scanner (freq dscan-freq &optional (order 3))
   (abs (expt (kmrcl:sinc (* pi (/ freq dscan-freq))) order)))
 
-(defun freq-mtf-scanner (dscan-freq mtf &optional (order 3))
-  (* dscan-freq (/ (asin (* x (exp  (/ (log mtf) order)))) pi)))