--- "Robert M." <[EMAIL PROTECTED]> wrote: > In any case, if you find that information about the > Canon raw format I would > be very interested.
Well, if you look here, someone in the linux community has already (and succesfully) attempted to peek into the RAW format. Take a look here: http://www.cybercom.net/~dcoffin/dcraw/ http://www.aim-dtp.net/aim/digicam/dcraw/ http://www.insflug.org/raw/software/tools/dcraw.php3 The source code file (dcraw.c), very clearly uses a Bayer mask for getting at the info and if you look at the history section, the author clearly mentions doing interpolation which means the body is *not* applying interpolation before creating raw file. IMO a RAW file is really a representation of the raw sensor data with the parameter settings in the header. This reinforces what I was saying earlier on in that various camera body RAW formats are highly dependent on the sensor (RAW Luminance only for each channel in whatever format the sensor is arranged) and that is why a DNG is really a higher level of abstraction than a RAW (for archival and perhaps greater compatibility in future). Sort of like having different Machine level instructions for different processors (RAW), while having a high level language across formats C/C++ etc. (DNG) as long as there are compilers available for each hardware platform (RAW to DNG conversion utilities). IMO They really complement each other. Another link here describes the raw data format in an excel spreadsheet format: http://www.wonderland.org/crw/ And and if you look here: http://www.cybercom.net/~dcoffin/dcraw/secrets.html The "CRW Files" section mentions the fact that a RAW is *not* a TIFF type file at all, although its heraders are TIFF style (perhaps that is why others refer to it as a TIFF type file, mistakenly). Although it talks about the Canon Powershot 600 only, I am sure the concept is same for other bodies, with compression applied (as is evident in the source code for dcraw.c accessible from the first link). The following steps are elucidated here as neccessary tp process the CRW file: <quote..> # Parse the CRW file and extract the pixel values. # Interpolate them to produce green, magenta, cyan, and yellow values for every non-edge pixel (thus the output will be 852x611). # Interpolate again to smooth out the color ratios. # Compute RGB for each pixel to collect statistics. # Compute RGB again, applying gamma correction and other adjustments. etc.... </quote ....> Finally, if the RAW file really was a TIFF type file (ie interpolation is already applied minus the camera settings), Canon would not have to go thru the trouble of supplying an FVU utility - they would just output either a JPEG (lossy) or TIFF (lossless) - no RAW neccessary. The DNG initiative would really be unneccessary - the TIFF has been around for a while and enjoys tremendous support with professionals and is a very well known and flexible format to work with. Think about it. At least, this is better than just a guess :) - Harman _______________________________ Do you Yahoo!? Declare Yourself - Register online to vote today! http://vote.yahoo.com * **** ******* *********************************************************** * For list instructions, including unsubscribe, see: * http://www.a1.nl/phomepag/markerink/eos_list.htm ***********************************************************
