# ImgConv.py """ Based on pyWiki 'Working With Images' @ http://wiki.wxpython.org/index.cgi/WorkingWithImages Modified to properly copy, create or remove any alpha in all conversion permutations. Note: The terms "plane", "band", "layer" and "channel" are used interchangibly. Tested on Win7 64-bit (6.1.7600) and Win XP SP3 (5.1.2600) using Python 32-bit. Platform Windows 6.1.7600 Python 2.5.4 (r254:67916, Dec 23 2008, 15:10:54) [MSC v.1310 32 bit (Intel) (x86)] Python wx 2.8.10.1 Pil 1.1.7 Ray Pasco pascor(at)verizon(dot)net Last modification: 2011-04-02 This code may be modified and distributed for any purpose whatsoever. """ import sys import wx # WxBmap <==> wxImage import Image # wxImage <==> PilImage. Used whenf converting to or from Pil images. #------------------------------------------------------------------------------ # image type image type image type # 1 2 3 # wx.Bitmap <==> wx.Image <==> pilImage #---------------------------- def WxBitmapFromPilImage( pilImage, addAlphaLayer=False, delAlphaLayer=False ) : """ 3 ==> 1 The default parameter valuess preserve any existing transparency, but do not add one if none exists. If the given pilImage mode is RGB, optionally create a new wxImage alpha transparency plane by calling with addAlphaLayer=True. If the given pilImage mode is RGBA, optionally create a new wxImage and delete any transparency plane by calling with delAlphaLayer=True. If given *both* addAlphaLayer=True *and* delAlphaLayer=True, addAlphaLayer=True will take precidence. """ # Pass on the given parameters. wxImage = WxImageFromPilImage( pilImage, addAlphaLayer, delAlphaLayer ) wxBitmap = wxImage.ConvertToBitmap() return wxBitmap #end def #---------------------------- def WxImageFromPilImage( pilImage, addAlphaLayer=False, delAlphaLayer=False ) : """ 3 ==> 2 The default parameter values preserve any existing transparency, but do not add one if it none exists in the source image. If the given source has no alpha, a new image with alpha transparency can be returned by calling with addAlphaLayer=True. If the given source image has alpha, a new image without alpha can be returned by calling with delAlphaLayer=True. """ wxImage = wx.EmptyImage( *pilImage.size ) # Has no transparency plane. pilMode = pilImage.mode hasAlpha = pilImage.mode[-1] == 'A' if hasAlpha or (not hasAlpha and addAlphaLayer) : pilImageRGBA = pilImage.copy() # Image mode might now be RGB, not RGBA. if pilImage.mode != 'RGBA' : pilImageRGBA = pilImageRGBA.convert( 'RGBA' ) #end if # The image mode is now gauranteed to be RGBA. pilImageStr = pilImageRGBA.tostring() # Convert all 4 image planes. # Extract just the RGB data pilRgbStr = pilImageRGBA.copy().convert( 'RGB').tostring() wxImage.SetData( pilRgbStr ) # Extract just the existing pilImage alpha plane data. pilAlphaStr = pilImageStr[3::4] # start at index 3 with a stride (skip) of 4. wxImage.SetAlphaData( pilAlphaStr ) elif delAlphaLayer or ((not hasAlpha) and (not addAlphaLayer)) : pilImageRGB = pilImage.copy().convert( 'RGB' ) wxImage.SetData( pilImageRGB.tostring() ) else : # All undecoded parameter permutations. This is for DEBUG. print '#### ERROR: ImgConv:WxImageFromPilImage(): Undecoded Parameter Combination.' sys.exit(1) #end if return wxImage #end def #---------------------------- def WxBitmapFromWxImage( wxImage, threshold=128 ) : """ 2 ==> 1 Any transparency mask or alpha transparency will be copied, to0. """ wxBmap = wxImage.ConvertToBitmap() return wxBmap #end def #---------------------------- def WxImageFromWxBitmap( wxBmap ) : """ 1 ==> 2 Any transparency mask or alpha transparency will be copied, to0. """ return wx.ImageFromBitmap( wxBmap ) #end def #------------------------------------------------------------------------------ def PilImageFromWxBitmap( wxBmap, keepTransp=True, createTransp=False, debug=False ) : """ 1 ==> 3 The default parameter values preserve any existing transparency, but do not add one if it none exists in the source image. If the given source has no alpha, a new image with alpha transparency can be returned by calling with addAlphaLayer=True. If the given source image has alpha, a new image without alpha can be returned by calling with delAlphaLayer=True. """ wxImage = WxImageFromWxBitmap( wxBmap ) return PilImageFromWxImage( wxImage ) # Always preserves any transparency. #end def #---------------------------- def PilImageFromWxImage( wxImage, keepTransp=True, createTransp=False, debug=False ) : """ 2 ==> 3 Default preserves any transparency. """ # These can never be simultaneous. hasMask = wxImage.HasMask() hasAlpha = wxImage.HasAlpha() if debug : print '>>>> PilImageFromWxImage(): Input Image has Alpha' # Always convert a mask into an aplha layer. # Deal with keeping or discarding this alpha later on. if hasMask : # Is always mutually exclusive with hasAlpha. if debug : print '>>>> PilImageFromWxImage(): Converting Input Image Mask to Alpha' wxImage.InitAlpha() # Covert the separate mask to a 4th alpha layer. hasAlpha = True #end if image_size = wxImage.GetSize() # All images here have the same size. # Create an RGB pilImage and stuff it with RGB data from the wxImage. pilImage = Image.new( 'RGB', image_size ) pilImage.fromstring( wxImage.GetData() ) # May need the separated planes if an RGBA image is needed. later. r_pilImage, g_pilImage, b_pilImage = pilImage.split() if hasAlpha : if keepTransp : # Ignore createTransp - has no meaning if debug : print '>>>> PilImageFromWxImage(): Keeping Transparency' # Must recompose the pilImage from 4 layers. r_pilImage, g_pilImage, b_pilImage = pilImage.split() # Create a Black L pilImage and stuff it with the alpha data # extracted from the alpha layer of the wxImage. pilImage_L = Image.new( 'L', image_size ) pilImage_L.fromstring( wxImage.GetAlphaData() ) # Create an RGBA PIL image from the 4 layers. pilImage = Image.merge( 'RGBA', (r_pilImage, g_pilImage, b_pilImage, pilImage_L) ) elif (not keepTransp) : # The RGB pilImage can be returned as it is now. if debug : print '>>>> PilImageFromWxImage(): Returning an RGB PIL Image.' #end if elif (not hasAlpha) and createTransp : # Ignore keepTransp - has no meaning if debug : print '>>>> PilImageFromWxImage(): Creating a New Transparency Layer' # Create a Black L mode pilImage. The resulting image will still # look the same, but will allow future transparency modification. pilImage_L = Image.new( 'L', image_size ) # Create an RGBA pil image from the 4 bands. pilImage = Image.merge( 'RGBA', (r_pilImage, g_pilImage, b_pilImage, pilImage_L) ) #end if return pilImage #end PilImageFromWxImage def #------------------------------------------------------------------------------