Precise bitmaps
- To: mathgroup at smc.vnet.net
- Subject: [mg96689] Precise bitmaps
- From: "Diamond, Mark" <dot at dot.dot>
- Date: Sat, 21 Feb 2009 19:37:11 -0500 (EST)
A question was asked back in 2005 about precise bitmaps. I have a similar
question with regard to Mathematica version 7.
Looking at the new image-manipulation functions in V7, I expected this to be
quick ... I'd like to be able to create a series of stimuli for use in an
experiment. The first step in creating the stimuli is to create a 512 x 512
greyscale image with a white background and which contains the drawn
objects.
I tried the following to create a JPEG image with dimensions 128x128 ...
circ=Graphics[Circle[{0,0},62]]
rasterCirc=Rasterize[circ,RasterSize->{128,128}]
Export["circle.jpg",rasterCirc]
but instead the image dimensions are 360 x 363 pixels. I had also hoped that
I could obtain an antialiased arc but the only antialiasing option seems to
be for Style, which then produces a non-Graphics object.
Can anyone see a simple (i.e., not very low-level programming) solution to
the problem within Mathematica? What have I missed conceptually that would
explain the 360x363 pixel dimensions instead of my expected 128x128? And is
there a way to obtain the anti-aliased circle?
Cheers,
Mark Diamond