On Sun, 2005-07-31 at 21:49 +0100, Daniel Carrera wrote: > Ian Lynch wrote: > > > Think of it like this. If I have an equation like Y = Sin(x) it will > > generate a nice oscillating curve. Now try and take a more complex curve > > and work out the equation that generated it. Its not at all so easy. So > > its quite easy to go from equations to curves, its a lot more difficult > > to go from curves back to equations and not simply a matter of reversing > > a formula. > > Not to mention that not all transformations are bijections. It's > possible that going from ODT to PDF is relatively straight forward and > going from PDF to ODT is nearly impossible. > > Consider a transformation that turns a Draw vector graphic into a PNG > bitmap. It would be impossible to turn that PNG back into a usable > vector graphic.
Not entirely true. There is software around that will make a pretty good job of tracing edges and turning some bit maps into usable vectors. Back in the early 90s I did this to a whole lot of hand drawn diagrams that had been scanned for an educational environment resource. Software was called Image Outliner and it was a Risc OS application. By tracing the diagrams to vectors it saved megabytes of storage which at that time was expensive and it also speeded up file handling and made scaling better. Mind I had two computers working over night every night for about two weeks doing the conversions. Certainly scanned images that are not simple line drawings would be a nightmare. I tried one as an experiment and it was actaully bigger as a vector than the original bit map and basically a complex horrendous mess! -- Ian Lynch <[EMAIL PROTECTED]> ZMSL --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
