> A jpeg never retains all the data. It is always lossy, but other than > that you popped all this out far better than I could have.
Ok, now I'm just going to be pedantic. JPEG is a standard that is defined by how a JPEG is decoded (that is, how applications are to interpret a JPEG file). The actual encoding of JPEGs isn't defined and as such is up to the encoder, as long as the resulting file conforms to the JPEG standard. Different encoders are going to encode in different ways, but every decoder must decode each file in exactly the same way. If you get a particularly clever encoder, it is possible to select a fourier transform that consists of fewer waveforms but more accurately approximates the original data. Furthermore, no encoder is restricted to retain all the data at 100% (and I'll agree with you here Schlake, it is likely that in camera encoders will be slightly lossy at 100%), but no encoder is prohibited from producing a jpeg that decodes to exactly the original either. David * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
