Will now generate converters that go thru intermedeate formats

diff --git a/Demo/sgi/video/imgconv.py b/Demo/sgi/video/imgconv.py
index a3a5d19d7a409af6b2be2fdf520d4af84a5a0ba7..3990ae1222d0120145e76a7af94e178bc31c9b54 100755 (executable)
--- a/Demo/sgi/video/imgconv.py
+++ b/Demo/sgi/video/imgconv.py
@@ -18,8 +18,14 @@ converters = [ \
          ('mono',  'grey',  mono2grey,            NOT_LOSSY), \
          ('grey2', 'grey',  imageop.grey22grey,   NOT_LOSSY), \
          ('grey4', 'grey',  imageop.grey42grey,   NOT_LOSSY), \
+         ('rgb',   'rgb8',  imageop.rgb2rgb8,     LOSSY), \
+         ('rgb8',  'rgb',   imageop.rgb82rgb,     NOT_LOSSY), \
+         ('rgb',   'grey',  imageop.rgb2grey,     LOSSY), \
+         ('grey',  'rgb',   imageop.grey2rgb,     NOT_LOSSY) \
 ]
 
+built = {}
+
 def addconverter(fcs, tcs, lossy, func):
        for i in range(len(converters)):
                ifcs, itcs, irtn, ilossy = converters[i]
@@ -29,10 +35,82 @@ def addconverter(fcs, tcs, lossy, func):
        converters.append((fcs,tcs,lossy,func))
 
 def getconverter(fcs, tcs):
+       #
+       # If formats are the same return the dummy converter
+       #
        if fcs == tcs: return null
-       
+       #
+       # Otherwise, if we have a converter return that one
+       #
        for ifcs, itcs, irtn, ilossy in converters:
                if (fcs, tcs) == (ifcs, itcs):
                        return irtn
-       raise error, 'Sorry, that conversion is not implemented'
-         
+       #
+       # Finally, we try to create a converter
+       #
+       if not built.has_key(fcs):
+               built[fcs] = enumerate_converters(fcs)
+       if not built[fcs].has_key(tcs):
+               raise error, 'Sorry, conversion from '+fcs+' to '+tcs+ \
+                         ' is not implemented'
+       if len(built[fcs][tcs]) == 3:
+               #
+               # Converter not instantiated yet
+               #
+               built[fcs][tcs].append(instantiate_converter(built[fcs][tcs]))
+       cf = built[fcs][tcs][3]
+       return cf
+
+def enumerate_converters(fcs):
+       cvs = {}
+       formats = [fcs]
+       steps = 0
+       while 1:
+               workdone = 0
+               for ifcs, itcs, irtn, ilossy in converters:
+                       if ifcs == fcs:
+                               template = [ilossy, 1, [irtn]]
+                       elif cvs.has_key(ifcs):
+                               template = cvs[ifcs][:]
+                               template[2] = template[2][:]
+                               if ilossy:
+                                       template[0] = ilossy
+                               template[1] = template[1] + 1
+                               template[2].append(irtn)
+                       else:
+                               continue
+                       if not cvs.has_key(itcs):
+                               cvs[itcs] = template
+                               workdone = 1
+                       else:
+                               previous = cvs[itcs]
+                               if template < previous:
+                                       cvs[itcs] = template
+                                       workdone = 1
+               if not workdone:
+                       break
+               steps = steps + 1
+               if steps > len(converters):
+                       print '------------------loop in emunerate_converters--------'
+                       print 'CONVERTERS:'
+                       print converters
+                       print 'RESULTS:'
+                       print cvs
+                       raise error, 'Internal error - loop'
+       return cvs
+
+def instantiate_converter(args):
+       list = args[2]
+       cl = RtConverters().init(list)
+       args.append(cl.convert)
+       return args
+
+class RtConverters():
+       def init(self, list):
+               self.list = list
+               return self
+
+       def convert(self, img, w, h):
+               for cv in self.list:
+                       img = cv(img, w, h)
+               return img