Darren Dale wrote: > Hi Joel, > > On Thursday 01 February 2007 11:09:11 am Joel Hedlund wrote: >> I believe I've found a bug in matplotlib which manifests after >> imshow(img, aspect='auto') when only a small portion of the image is >> displayed, e.g: when (xmax-xmin) << img.shape[1]. The effect of the bug >> is that the transparency for the entire image seems to vary, seemingly >> as a periodic funtion of (xmax-xmin). Explicitly setting the alpha >> channel for each pixel has no effect. >> >> The attached script generates a random image of a certain size, and >> plots it in four different subplots. The only thing that differs between >> the subplots are slight variations in x_max. The four subplots are labeled: >> >> 1) The background image is visible. >> 2) The background image is not visible! >> 3) The background image is faded! >> 4) The background image is again visible! >> >> which reflects the actual result on my system. As the subplots are >> scaled (for example by resizing the window), the intensity then varies >> in a periodic manner in each of the subplots. >> >> The expected result is of course that the background should be fully >> visible in all subplots. > > I can verify this behavior, more or less. I observe that the figure.dpi rc > setting influences the results (I tried 86.23 and 200).
This sounds like the same bug that was noted a few months ago, in which repeated zooming to a very small part of the image ends up washing out the color entirely. I think that it was also connected with very slow rendering. Eric ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier. Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Matplotlib-users mailing list Matplotlib-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-users
