Actually I think that simon is right, albeit that it’s not usually referred to as aliasing in this context.
I think the blurring is an artefact caused because the frequency of the sampling used by the JPG compression is lower than the frequency of the original image.
In other words if the JPG compression squares were small enough (i.e. high frequency enough) then the blurring would disappear – but the file size would increase.
Well if that’s the case Graham, then Simon’s definition of aliasing and Bez’s definition of compression artefacting are basically the same thing, and we’re all just talking at crossed purposes. I think Bez’s original point, about using the appropriate file format for the job, still stands though.
Hi Bez, how’s tricks?