""" The image module supports basic image loading, rescaling and display operations. """ from __future__ import division import sys, os from matplotlib import rcParams from artist import Artist from colors import colorConverter import cm import numerix import numerix.ma as ma from numerix import arange, asarray, UInt8, Float32, repeat, NewAxis, typecode import _image class AxesImage(Artist, cm.ScalarMappable): def __init__(self, ax, cmap = None, norm = None, interpolation=None, origin=None, extent=None, filternorm=1, filterrad=4.0, **kwargs ): """ interpolation and cmap default to their rc settings cmap is a colors.Colormap instance norm is a colors.Normalize instance to map luminance to 0-1 extent is a data xmin, xmax, ymin, ymax for making image plots registered with data plots. Default is the image dimensions in pixels Additional kwargs are matplotlib.artist properties """ Artist.__init__(self) cm.ScalarMappable.__init__(self, norm, cmap) if origin is None: origin = rcParams['image.origin'] self.origin = origin self._extent = extent self.set_filternorm(filternorm) self.set_filterrad(filterrad) # map interpolation strings to module constants self._interpd = { 'nearest' : _image.NEAREST, 'bilinear' : _image.BILINEAR, 'bicubic' : _image.BICUBIC, 'spline16' : _image.SPLINE16, 'spline36' : _image.SPLINE36, 'hanning' : _image.HANNING, 'hamming' : _image.HAMMING, 'hermite' : _image.HERMITE, 'kaiser' : _image.KAISER, 'quadric' : _image.QUADRIC, 'catrom' : _image.CATROM, 'gaussian' : _image.GAUSSIAN, 'bessel' : _image.BESSEL, 'mitchell' : _image.MITCHELL, 'sinc' : _image.SINC, 'lanczos' : _image.LANCZOS, 'blackman' : _image.BLACKMAN, } # reverse interp dict self._interpdr = dict([ (v,k) for k,v in self._interpd.items()]) if interpolation is None: interpolation = rcParams['image.interpolation'] self.set_interpolation(interpolation) self.axes = ax self._imcache = None self.update(kwargs) def get_size(self): 'Get the numrows, numcols of the input image' if self._A is None: raise RuntimeError('You must first set the image array') return self._A.shape[:2] def set_alpha(self, alpha): """ Set the alpha value used for blending - not supported on all backends ACCEPTS: float """ Artist.set_alpha(self, alpha) self._imcache = None def changed(self): """ Call this whenever the mappable is changed so observers can update state """ self._imcache = None cm.ScalarMappable.changed(self) def make_image(self, magnification=1.0): if self._A is None: raise RuntimeError('You must first set the image array or the image attribute') if self._imcache is None: if typecode(self._A) == UInt8: im = _image.frombyte(self._A, 0) im.is_grayscale = False else: x = self.to_rgba(self._A, self._alpha) im = _image.fromarray(x, 0) if len(self._A.shape) == 2: im.is_grayscale = self.cmap.is_gray() else: im.is_grayscale = False self._imcache = im if self.origin=='upper': im.flipud_in() else: im = self._imcache bg = colorConverter.to_rgba(self.axes.get_frame().get_facecolor(), 0) im.set_bg( *bg) # image input dimensions im.reset_matrix() numrows, numcols = im.get_size() im.set_interpolation(self._interpd[self._interpolation]) xmin, xmax, ymin, ymax = self.get_extent() dxintv = xmax-xmin dyintv = ymax-ymin # the viewport scale factor sx = dxintv/self.axes.viewLim.width() sy = dyintv/self.axes.viewLim.height() if im.get_interpolation()!=_image.NEAREST: im.apply_translation(-1, -1) # the viewport translation tx = (xmin-self.axes.viewLim.xmin())/dxintv * numcols ty = (ymin-self.axes.viewLim.ymin())/dyintv * numrows l, b, widthDisplay, heightDisplay = self.axes.bbox.get_bounds() widthDisplay *= magnification heightDisplay *= magnification im.apply_translation(tx, ty) im.apply_scaling(sx, sy) # resize viewport to display rx = widthDisplay / numcols ry = heightDisplay / numrows im.apply_scaling(rx, ry) im.resize(int(widthDisplay+0.5), int(heightDisplay+0.5), norm=self._filternorm, radius=self._filterrad) return im def draw(self, renderer, *args, **kwargs): if not self.get_visible(): return im = self.make_image(renderer.get_image_magnification()) l, b, widthDisplay, heightDisplay = self.axes.bbox.get_bounds() renderer.draw_image(l, b, im, self.axes.bbox) def pick(self, mouseevent): 'return true if the data coords of mouse click are within the extent of the image' if not self.pickable(): return picker = self.get_picker() if callable(picker): hit, props = picker(self, mouseevent) if hit: self.figure.canvas.pick_event(mouseevent, self, **props) elif picker: xmin, xmax, ymin, ymax = self.get_extent() xdata, ydata = mouseevent.xdata, mouseevent.ydata #print xdata, ydata, xmin, xmax, ymin, ymax if (xdata is not None and ydata is not None and xdata>=xmin and xdata<=xmax and ydata>=ymin and ydata<=ymax): self.figure.canvas.pick_event(mouseevent, self) def write_png(self, fname, noscale=False): """Write the image to png file with fname""" im = self.make_image() if noscale: numrows,numcols = im.get_size() im.reset_matrix() im.set_interpolation(0) im.resize(numcols, numrows) im.flipud_out() im.write_png(fname) def set_data(self, A, shape=None): """ Set the image array ACCEPTS: numeric/numarray/PIL Image A""" # check if data is PIL Image without importing Image if hasattr(A,'getpixel'): X = pil_to_array(A) else: X = ma.asarray(A) # assume array if (typecode(X) != UInt8 or len(X.shape) != 3 or X.shape[2] > 4 or X.shape[2] < 3): cm.ScalarMappable.set_array(self, X) else: self._A = X self._imcache =None def set_array(self, A): """ retained for backwards compatibility - use set_data instead ACCEPTS: numeric/numarray/PIL Image A""" self.set_data(A) def get_interpolation(self): """ Return the interpolation method the image uses when resizing. One of 'bicubic', 'bilinear', 'blackman100', 'blackman256', 'blackman64', 'nearest', 'sinc144', 'sinc256', 'sinc64', 'spline16', 'spline36' """ return self._interpolation def set_interpolation(self, s): """ Set the interpolation method the image uses when resizing. ACCEPTS: ['bicubic' | 'bilinear' | 'blackman100' | 'blackman256' | 'blackman64', 'nearest' | 'sinc144' | 'sinc256' | 'sinc64' | 'spline16' | 'spline36'] """ s = s.lower() if not self._interpd.has_key(s): raise ValueError('Illegal interpolation string') self._interpolation = s def get_extent(self): 'get the image extent: xmin, xmax, ymin, ymax' if self._extent is not None: return self._extent else: numrows, numcols = self.get_size() iwidth, iheight = numcols, numrows #return 0, width, 0, height tmp, tmp, dwidth, dheight = self.axes.bbox.get_bounds() sx = dwidth / iwidth sy = dheight / iheight return 0, 1.0/sx*dwidth, 0, 1.0/sy*dheight def set_filternorm(self, filternorm): """Set whether the resize filter norms the weights -- see help for imshow ACCEPTS: 0 or 1 """ if filternorm: self._filternorm = 1 else: self._filternorm = 0 def get_filternorm(self): 'return the filternorm setting' return self._filternorm def set_filterrad(self, filterrad): """Set the resize filter radius only applicable to some interpolation schemes -- see help for imshow ACCEPTS: positive float """ r = float(filterrad) assert(r>0) self._filterrad = r def get_filterrad(self): 'return the filterrad setting' class NonUniformImage(AxesImage): def __init__(self, ax, cmap = None, norm = None, extent=None, ): AxesImage.__init__(self, ax, cmap = cmap, norm = norm, extent=extent, interpolation = 'nearest', origin = 'lower', ) def make_image(self, magnification=1.0): if self._A is None: raise RuntimeError('You must first set the image array') x0, y0, v_width, v_height = self.axes.viewLim.get_bounds() l, b, width, height = self.axes.bbox.get_bounds() width *= magnification height *= magnification im = _image.pcolor(self._Ax, self._Ay, self._A, height, width, (x0, x0+v_width, y0, y0+v_height), ) bg = colorConverter.to_rgba(self.axes.get_frame().get_facecolor(), 0) im.set_bg(*bg) return im def set_data(self, x, y, A): x = asarray(x).astype(Float32) y = asarray(y).astype(Float32) A = asarray(A) if len(x.shape) != 1 or len(y.shape) != 1\ or A.shape[0:2] != (y.shape[0], x.shape[0]): raise TypeError("Axes don't match array shape") if len(A.shape) not in [2, 3]: raise TypeError("Can only plot 2D or 3D data") if len(A.shape) == 3 and A.shape[2] not in [1, 3, 4]: raise TypeError("3D arrays must have three (RGB) or four (RGBA) color components") if len(A.shape) == 3 and A.shape[2] == 1: A.shape = A.shape[0:2] if len(A.shape) == 2: if typecode(A) != UInt8: A = (self.cmap(self.norm(A))*255).astype(UInt8) else: A = repeat(A[:,:,NewAxis], 4, 2) A[:,:,3] = 255 else: if typecode(A) != UInt8: A = (255*A).astype(UInt8) if A.shape[2] == 3: B = zeros(tuple(list(A.shape[0:2]) + [4]), UInt8) B[:,:,0:3] = A B[:,:,3] = 255 A = B self._A = A self._Ax = x self._Ay = y self._imcache = None def set_array(self, *args): raise NotImplementedError('Method not supported') def set_interpolation(self, s): if s != 'nearest': raise NotImplementedError('Only nearest neighbor supported') def get_extent(self): if self._A is None: raise RuntimeError('Must set data first') return self._Ax[0], self._Ax[-1], self._Ay[0], self._Ay[-1] def set_filternorm(self, s): pass def set_filterrad(self, s): pass def set_norm(self, norm): if self._A is not None: raise RuntimeError('Cannot change colors after loading data') cm.ScalarMappable.set_norm(self, norm) def set_cmap(self, cmap): if self._A is not None: raise RuntimeError('Cannot change colors after loading data') cm.ScalarMappable.set_cmap(self, norm) class FigureImage(Artist, cm.ScalarMappable): def __init__(self, fig, cmap = None, norm = None, offsetx = 0, offsety = 0, origin=None, ): """ cmap is a colors.Colormap instance norm is a colors.Normalize instance to map luminance to 0-1 """ Artist.__init__(self) cm.ScalarMappable.__init__(self, norm, cmap) if origin is None: origin = rcParams['image.origin'] self.origin = origin self.figure = fig self.ox = offsetx self.oy = offsety def get_size(self): 'Get the numrows, numcols of the input image' if self._A is None: raise RuntimeError('You must first set the image array') return self._A.shape[:2] def make_image(self, magnification=1.0): # had to introduce argument magnification to satisfy the unit test # figimage_demo.py. I have no idea, how magnification should be used # within the function. It should be !=1.0 only for non-default DPI # settings in the PS backend, as introduced by patch #1562394 # Probably Nicholas Young should look over this code and see, how # magnification should be handled correctly. if self._A is None: raise RuntimeError('You must first set the image array') x = self.to_rgba(self._A, self._alpha) im = _image.fromarray(x, 1) im.set_bg( *colorConverter.to_rgba(self.figure.get_facecolor(), 0) ) im.is_grayscale = (self.cmap.name == "gray" and len(self._A.shape) == 2) if self.origin=='upper': im.flipud_out() return im def draw(self, renderer, *args, **kwargs): if not self.get_visible(): return im = self.make_image() renderer.draw_image(self.ox, self.oy, im, self.figure.bbox) def write_png(self, fname): """Write the image to png file with fname""" im = self.make_image() im.write_png(fname) def imread(fname): """ return image file in fname as numerix array Return value is a MxNx4 array of 0-1 normalized floats """ handlers = {'png' :_image.readpng, } basename, ext = os.path.splitext(fname) ext = ext.lower()[1:] if ext not in handlers.keys(): raise ValueError('Only know how to handled extensions: %s' % handlers.keys()) handler = handlers[ext] return handler(fname) def pil_to_array( pilImage ): if pilImage.mode in ('RGBA', 'RGBX'): im = pilImage # no need to convert images in rgba format else: # try to convert to an rgba image try: im = pilImage.convert('RGBA') except ValueError: raise RuntimeError('Unknown image mode') x_str = im.tostring('raw',im.mode,0,-1) x = numerix.fromstring(x_str,numerix.UInt8) x.shape = im.size[1], im.size[0], 4 return x