Thread: [Matplotlib-users] FigureCanvas transparency

hi, with the simple script below, how can i make the image have a
transparent background instead of white? it's saving RGB, not RGBA.
thanks,
-brent
import matplotlib
matplotlib.use('Agg')
from matplotlib.backends.backend_agg import FigureCanvasAgg as FigureCanvas
from matplotlib.figure import Figure
fig = Figure()
canvas = FigureCanvas(fig)
dpi = 64
fig.set_size_inches(256/dpi, 256/dpi)
#fig.figurePatch.set_alpha(1.)
fig.set_alpha(1.)
ax = fig.add_axes((0,0,1,1), axis_bgcolor=(1, 1, 1, 1.), alpha=1.,
frame_on=False, xticks=(), yticks=())
ax.plot([1,2,3])
fig.set_facecolor((1.,1.,1.,1.))
canvas.print_figure('t.png', dpi=dpi, facecolor=(1.,1.,1.,1.))

sending again, doesnt seem to have gone through...
hi, with the simple script below, how can i make the image have a
transparent background instead of white? it's saving RGB, not RGBA.
thanks,
-brent
import matplotlib
matplotlib.use('Agg')
from matplotlib.backends.backend_agg import FigureCanvasAgg as FigureCanvas
from matplotlib.figure import Figure
fig = Figure()
canvas = FigureCanvas(fig)
dpi = 64
fig.set_size_inches(256/dpi, 256/dpi)
#fig.figurePatch.set_alpha(1.)
fig.set_alpha(1.)
ax = fig.add_axes((0,0,1,1), axis_bgcolor=(1, 1, 1, 1.), alpha=1.,
frame_on=False, xticks=(), yticks=())
ax.plot([1,2,3])
fig.set_facecolor((1.,1.,1.,1.))
canvas.print_figure('t.png', dpi=dpi, facecolor=(1.,1.,1.,1.))