2003.04.08 13:56 "jpegs", by John Carter

Hi

seeing as jpegs can be imbedded in tiffs i thought some could answer my question.

I've just started writing code (in c) to load a jfif compliant jpeg into memory. I've noticed in the file im trying to read that it is made up of markers such as FF D8 -> SOI, or FF DB -> Data Quantization Table marker. However having browsed through jpeg fine interchange format spec 1.01 and 1.02 http://www.w3.org/Graphics/JPEG/jfif.txt it seems to put an SOF marker after the SOI marker.

I was wondering if these markers can appear in

  1. any order, in which case I would would be inclined to parse the whole file and put the contents of each marker/struct into a super struct that i could then parse. or
  2. the markers follow a particular order.

option 1 would be more flexible i suppose and would be slightly similar to how the TIFF file format works

any ideas

thanks jc

____________________________

John Carter
BSS O&M Development group,
Motorola,
Mahon Industrial Estate,
Cork.