blabla=randn(40,500)
tuabuela=PyPlot.figure(frameon=false)
gca().set_axis_off()
subplots_adjust(top = 1, bottom = 0, right = 1, left = 0,
            hspace = 0, wspace = 0)

tu=imshow(blabla, interpolation="gaussian")
margins(0,0)
savefig("outname.png", bbox_inches="tight", pad_inches=0.01, frameon=false, dpi=90)