Quote:
...it seems to me
that the algorithm used by the Iliad results in anti-aliasing for scanned text.
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Resampling, more probably -- the source pixels have to be transformed to a) the pixel raster, and to b) the pixel 'depth' (number of grey levels) of each pixel. I assume you did not resample the images or encode lossily -- that would introduce further possible variations to play with. (LATER: encoding is CCITTFaxEncoding, so it's non-lossy, and size is approx. 5 x 8 in, so probably no resampling, so that's OK.)
As the Sony and the iLiad have different screens, it's not easy to say if this is a hardware difference or a software difference: the screens need not display greyscales according to the same response curve (quite apart from differences between individual screens and individual pixels). The zoom is probably also a factor -- unless you ensure that both systems should produce an 'a' in exactly the same subpixel position, minor differences may be very visible. That there's different software involved is certain: The Sony Reader has an Adobe PDF reader, while the iLiad uses the xpdf reader, and they could easily use different resampling algorithms.