jburnes@crash.cts.com (Jim Burnes) (12/12/90)
Anyone: When asking Dan Baker of CATS for assistance in finding out the format for 24bit IFF files, he forwarded to me a transcript of AmigaMail from Commodore. Below we have an excerpt... The Standard The bit ordering shown below has been chosen as the default for deep ILBMs. This is the bit ordering saved by the ASDG color scanner and read by the associated ASDG software. It is also read by Active Circuits image management, Targa transfer software and products from other vendors. Default standard deep ILBM bit ordering: saved first -------------------------------------------------> saved last R0 R1 R2 R3 R4 R5 R6 R7 G0 G1 G2 G3 G4 G5 G6 G7 B0 B1 B2 B3 B4 B5 B6 B7 Another bit ordering currently in use is shown below. This is the ordering used by NewTek in their Video Toaster, and read by Digipaint III. Unfortunately, other developers saving and reading deep ILBMs did not agree with this format. However, since you may want to parse or convert it, the NewTek format is as follows: NewTek deep ILBM bit ordering: saved first ------------------------------------------------------> saved last R7 G7 B7 R6 G6 B6 R5 G5 B5 R4 G4 B4 R3 G3 B3 R2 G2 B2 R1 G1 B1 R0 G0 B0 I'm trying to figure out how to interpret this. My guess is that it says: (for the ASDG 24bit files) The body of the ILBM contains: o One whole plane of data containing the least significant bit of the red values. o One whole plane of data containing the next most significant bit of the red values. ...For all red bits o One whole plane of data for each of the succesive green bits. o One whole plane of data for each of the successive blue bits. (for the NEWTEK video toaster/toaster paint/digipaint III) o One whole plane of data for the most significant bit of the red bits. o One whole plane of data for the most sig bit of the green bits. o One whole plane of data for the most sig bit of the blue bits. ... and so on for the next least most significant bit planes. Of course each of these successive bit planes are subject to run-length encoding like all ILBM files. I believe the format for this group coding is... <group> ::= <HeaderByte><Plane Data> where Let the headerByte be N. o If N is positive then N bytes will follow which should be interpreted as normal plane data. o If N is negative then repeat the next byte -N+1 times. Can anyone tell me if my assumptions are correct? Is Newtek still using their unique version of 24bit rgb ILBM files or have they joined the ASDG school? HELP!!!! Best Regards, Jim Burnes -- ------------------------------------------------------------------- It's the man in the White House, the man under the steeple Passing out drugs to the American people I don't believe in anything, nothing is free They're feeding our people that Government Cheese the RainMakers ------------------------------------------------------------------ Jim Burnes: jburnes@crash.cts.com mabellnet: (314) 962-2399 ------------------------------------------------------------------
mark@calvin..westford.ccur.com (Mark Thompson) (12/13/90)
In article <6271@crash.cts.com> jburnes@crash.cts.com (Jim Burnes) writes: >When asking Dan Baker of CATS for assistance in finding out the format for >24bit IFF files, he forwarded to me a transcript of AmigaMail from >Commodore. Below we have an excerpt.....deleted... >Can anyone tell me if my assumptions are correct? Is Newtek still using >their unique version of 24bit rgb ILBM files or have they joined the >ASDG school? If I read your article right, you have interpreted it correctly. However, the NewTek Video Toaster and Toaster Paint do conform to the standard IFF24 format. You can take any 24 bit image created on the Toaster and freely read it into other programs that support IFF24 such as ASDG's TAD. I believe the the other format you mentioned is an old NewTek format supported by DigiView. If you would like some code that reads compressed and uncompressed IFF24 images, I wrote a conversion utility for use with the PBMPlus package that will do this. Drop me a line if you are interested. By the way, you can read an IFF24 image into DigiView and process it, but if you want to convert it to an image viewable on any Amiga, TAD does a MUCH better job. +--------------------------------------------------------------------------+ | Mark Thompson | | mark@westford.ccur.com | | ...!{decvax,uunet}!masscomp!mark Designing high performance graphics | | (508)392-2480 engines today for a better tomorrow. | +------------------------------------------------------------------------- +