============================================================================ ChangeFSI file formats ============================================================================ This file lists the file formats that ChangeFSI uses, and then gives more detail on each one. Summary of formats ================== Input formats ------------- RISC OS sprites ArVis 15-bit HIP + LOP sprites Watford digitiser pictures, 512Χ256, 64 greys - and triple red, green, blue separations ProArtisan compressed pictures, 640Χ256, 256 colours JPEG 'JFIF' files Kodak PhotoCD images TimeStep satellite images, 800Χ800, 256 greys PC TGA images MTV 24-bit PIC images QRT 24-bit RAW images ZSoft .PCX files Degas PI1, PI2, PI3 images !Translator Clear format files CCIR 601 4:2:2 images !RayShade 'RGB' images TimeStep satellite images, 128Χ256, 256 greys - and triple red, green, blue separations Wild Vision Hawk V12, 512Χ512, 256 greys AIM/Wild Vision Hawk V10, 256Χ256, 256 greys Wild Vision/Hawk V9, 256Χ256, 24 bit triple image Wild Vision Hawk V9, 512Χ256, 12-bit colour Wild Vision Hawk V9 Mk II, 16-bit colour Pineapple 16 bit per pixel images FITS astronomical format images Irlam Instruments YUV 411 files Irlam Instruments 24-bit files Windows 3 .BMP files Compuserve's GIF files up to 8 bit per pixel .PIC 8 bit per pixel files Sun 'pixrect' raster files GEM IMG images Apollo GPR 16-colour images RIX Softworks ColoRIX 8 bit per pixel files TIFF pictures UNIX rle format files Portable Bit Map (pbm) binary encoded formats ChangeFSI packed portable bitmaps PocketBook I and II PIC format files Electronic Art's IFF ILBM pictures MILLIPEDE PRISMA, 768Χ576, 8-bit colour images MacPaint files, 576Χ720, 1 bit per pixel Mac PICT2 v2 8 and 24/32 bit per pixel RT 24-bit run length coded IMAGE files PC EGA .DSP images, 640Χ350, 16 colours Kodak RGB images, 24 bits per pixel Output formats -------------- RISC OS sprites AIM/Wild Vision Hawk V10, 256Χ256, 256 greys JPEG 'JFIF' files Portable Bit Map (pbm) ASCII and binary encoded formats ChangeFSI packed portable bitmaps Details of formats ================== RISC OS sprites --------------- The old RISC OS sprite format ····························· Contains 1, 2, 4 or 8 bits per pixel with a modification palette of up to 16 entries; any number of pixels wide and high uncompressed. Details are in Acorn's Programmer's Reference Manual.  Recognised by file type FF9 (a paint brush and house icon).  Details of how many bits per pixel and the pixel size are obtained from the operating system (rather than being in the file) from the "MODE" number. Mode extensions can result in a source image containing a MODE number which your computer does not understand.  Mask information ignored.  Lefthand wastage ignored. The new RISC OS sprite format ····························· Contains 1, 2, 4, 8, 16 or 32 bits per pixel.  Recognised by file type FF9.  No problem with mode extensions: information is coded into the format.  Mask information ignored. ArVis 15-bit HIP + LOP sprites ------------------------------ Contains 5 bits of red, green and blue information encoded into two RISC OS sprites "HIP." and "LOP." comprising a 640 pixel wide and 256 line tall image with pixels sized 1:2. Details from ArVis Multimedia.  Recognised by file type FF9, and the file is beneath a directory named HIP, and a corresponding LOP file exists.  Uncompressed (indeed represents 16 bits instead of 15). Watford digitiser pictures -------------------------- Contains a run length encoded 64 grey level 512 pixel wide, 256 line image, with pixels sized 1:2. Details from Watford Electronics Ltd.  Recognised by file type DFA (a small grey picture of Stevie Nicks).  Warning: don't forget to save the pictures in *un-dithered* state! When used with a colour converter, ChangeFSI can read three colour separations stored in a directory of separate "red", "green" and "blue" files of file type DFA. Beware of auto-gain/contrast when using such information! ProArtisan compressed pictures ------------------------------ Contains a (mildly) compressed MODE 15 (640 by 256 by 256 colours) picture. Details from Clares.  Recognised by file type DE2 (a beige monitor in a grey surround). JPEG 'JFIF' files ----------------- The JPEG File Interchange Format contains up to 24 bits R,G,B, compressed by the JPEG compression system.  Recognised by file type C85 (an eye), or by JFIF at offset 6 in the file. (You may have to cut headers off files, particularly if they are from Macs).  Often highly compressed.  If ChangeFSI$Cache is large enough (i.e. bigger than the file), then high speed routines are used to decompress. Otherwise:  ChangeFSI calls a djpeg routine. This can be on the Run$Path, implemented as an Alias (in which case it *must* use WimpTask to start) or found inside ChangeFSI$Dir if all else fails. cjpeg (the compressor) is also available inside ChangeFSI$Dir - you will need to convert the image to P6 format before it can be compressed. Djpeg and cjpeg are by the PD JPEG groupŒ  Œ and therefore slow. Needs a lot of space in .  No resolution specified; equal to mode 27 assumed. Kodak PhotoCD images -------------------- 24 bit per pixel images at various resolutions.  Recognised by file type BE8, or the file's name ends /PCD.  Set ChangeFSI$PCDIndex to read resolutions other than base (=3). TimeStep satellite images, 800Χ800 ---------------------------------- This gives an uncompressed 800 by 800 with 256 grey levels.  Recognised by file type 7A0 (icon never seen).  No resolution specified; equal to mode 27 assumed.  Documentation never seen. An extra header file ! is not understood at all. PC TGA images ------------- This 'Targa' format is used by TrueVision for Vista boards. Up to 32 bits per pixel.  Recognised by file type 69D, or the file's name ends with TGA or VDA.  Only uncompressed formats readable.  Only 8 and 16 bit per pixel formats tested. MTV 24-bit PIC images --------------------- Output from Mark Terrence VandeWettering public domain ray tracer: arbitrary size in 2^24 colours, uncompressed. Documentation part of MTV. Also used by "RayShade".  Recognised by file type 699, or the file is beneath a directory named PIC.  No resolution specified; equal to mode 27 assumed. QRT 24-bit RAW images --------------------- Output from Steve Koren's public domain ray tracer: arbitrary size in 2^24 colours, uncompressed. Documentation part of QRT.  Recognised by file type 698, or the file's name is RAW.  No resolution specified; equal to mode 27 assumed. ZSoft .PCX files ---------------- Used by PC Paintbrush. Usually a 4 bit per pixel image (CGA, EGA, VGA), but can be 1-8 bits per pixel.  Recognised by file type 697, or &0A,&00|02|03|04|05,&01 at the start of the file, or the file is beneath a directory named PCX, or the file's name ends /PCX.  Intelligent check for resolution of the DACs on the PC card. Use -info to find out what ChangeFSI thinks it is.  Pixel size information read. You may need to stop the scaling with -nosize, since it's often wrong. Degas PI1, PI2, PI3 images -------------------------- The Atari ST "Degas" format contains 1, 2 or 4 bits per pixel, clear or run length encoded. RISC OS file type by John Kortink of !Translator.  Recognised by file type 691.  No documentation, and only 5 images read.  No resolution specified; equal to mode 27 assumed. !Translator Clear format files ------------------------------ This provides 1, 2, 4, 8 and 24 bits per pixel.  Recognised by file type 690.  Uncompressed - especially for <8 bits per pixel, which is recorded at one byte per pixel.  No resolution specified; equal to mode 27 assumed. CCIR 601 4:2:2 images --------------------- Contain 720 pixels by 288 rows (PAL) (243 rows NTSC), YUV coded, with pixels sized 1:2.  Recognised by file type 601.  One field only. !RayShade 'RGB' images ----------------------  Recognised by file type 371. TimeStep satellite images, 128Χ256 ---------------------------------- Giving an uncompressed 128 pixels wide by 256 lines with 256 grey levels, pixels sized 2:1. Used by TimeStep's !ImProcess application.  Recognised by file type 300 (an "i" in a document frame).  Documentation never seen.  A bit coarse. The grey levels represent intensity in various different wave bands. By naming files of type 300 "red", "green" and "blue", and handing ChangeFSI the directory, you can produce a false colour image. Hours of experimentation can produce an almost reasonable pictureŒ Wild Vision Hawk V12 -------------------- This provides an uncompressed 512 by 512 image with 256 grey levels.  Recognised by file type 006.  No resolution specified; equal to mode 27 assumed. AIM/Wild Vision Hawk V10 ------------------------ This provides an uncompressed 256 by 256 image with 256 grey levels. Details from Delft University of Technology and ECD Computers Delft B.V.  Recognised by file type 004 (a picture of 'Trui' with "TU" in blue).  ChangeFSI can write to this format; specify the output mode as "AIM", and specify "=" in the sizing to get a 256 by 256 output (otherwise it will be the same size as the source image).  No resolution specified; equal to mode 27 assumed.  The associated file + (file type 010) which contains additional information is ignored by ChangeFSI. The grey levels may represent intensity in various different wave bands. By naming files "red", "green" and "blue" and handing ChangeFSI the directory (see Wild Vision/Hawk V9 24 bit triple image below), you can produce a false colour image. Hours of experimentation can produce an almost reasonable pictureŒ  As a special feature, ChangeFSI will also write out files in this format if you specify the mode string as "AIM". You should use the = operation to restrict the picture to 256x256y, otherwise it will be the same size as the input. Wild Vision/Hawk V9 24 bit triple image --------------------------------------- Three files, resolution 256 by 256, giving a 24-bit image.  Recognised by a directory holding type 004 files named RED, GREEN and BLUE. Wild Vision Hawk V9 12-bit colour --------------------------------- This provides an uncompressed 512 by 256 image with 4 bits of red, green and blue, pixels sized 1:2. Also used by SnapShot.  Recognised by 'MercSoft' or 'SnapShot' at the start of the file. Wild Vision Hawk V9 Mk II, 16-bit colour ----------------------------------------  Recognised by 'MercSof1' at the start of the file. Pineapple 16 bit per pixel images --------------------------------- Pineapple Software's colour digitiser format contains 6 bits of green, 5 bits of red and blue information filed as a single data file starting "FSIfile" comprising a 512 pixel wide and 256 line tall image with pixels sized 1:2.  Recognised by 'FSIFile' at the start of the file.  Uncompressed. FITS astronomical format images ------------------------------- The "Flexible Image Transport System" (FITS) format is used for astronomical data. Up to 16 bits per pixel component.  Recognised by 'SIMPLE ' at the start of the file.  Only 8 and 16 bit per pixel component formats tested.  Only two files ever seen!  No resolution specified; equal to mode 27 assumed. Irlam Instruments YUV 411 files ------------------------------- 7 bits Y, up to 7 bits U and V.  Recognised by 'IRLAM YUV 411' at the start of the file.  No resolution specified; equal to mode 27 assumed. Irlam Instruments 24-bit files ------------------------------ 24 bit per pixel from colour scanner.  Recognised by 'Irlam' at the start of the file.  No resolution specified; equal to mode 27 assumed.  May need gamma correction.  Can be written. Windows 3 .BMP files -------------------- Used by MicroSoft in Windows 3 and PaintBrush for Windows 3. Provides an arbitrary sized image and 1, 4 or 8 bits per pixel. Uncompressed.  Recognised by 'BM' at the start of the file; or 'RIFF' at the start of the file, and 'RDIBdata' at offset 8 and 'BM' at offset 20 in file.  No resolution specified; equal to mode 27 assumed.  Documentation never seen - 7 files examined and intelligent guesses made! Compuserve's GIF files up to 8 bit per pixel -------------------------------------------- Used for wide area network transfer of images. It provides an LZW compressed up to 256 colours from 2^24 arbitrary sized image. Details from CompuServe (USA), or usenet.  Recognised by 'GIF8' at the start of the file.  LZW compression is efficient even for dithered images.  ChangeFSI can decompress LZW quickly.  No resolution specified; equal to mode 27 assumed.  Many low quality images around from PCs. .PIC 8 bit per pixel files -------------------------- Used for some VGA demos, the format provides an uncompressed 320 by 200 by 256 colour (from 2^24) VGA screen dump.  Recognised by 'AV_VO' at the start of the file.  Documentation never seen.  Pixel size assumed the same as MODE 13 (45 pixels per inch). Sun 'pixrect' raster files -------------------------- Used under SunOS and also under X11. Commonly 1 or 8 bits per pixel, but up to 24 bits per pixel can be found (see the Sun NeWS release tape!).  Recognised by &956AA659 at the start of the file.  No resolution specified; equal to mode 27 assumed.  Sun didn't specify the pixel ordering of 24 bit per pixel images: many assume RGB when it was actually BGR. Change byte &17 in the Sun rasterfile between 1 and 3 if you have a problem. GEM IMG images -------------- Used by Digital Research's GEM (and GEM Paint) on both PC and Atari ST. Provides an arbitrary sized image and number of bits per pixel (though it's only usually used with up to 5 bits per pixel) and pixel size. Compressed by run length encoding and line repeats.  Recognised by &08000100 at the start of the file ("version 1, header length 8"), or the file is beneath a directory named IMG , or the file's name ends /IMG.  Planar file format slow to read.  Palette not specified: ChangeFSI assumes linear shades of grey. You might need to use -invert if the image is a negative.  The size of a pixel is specified in microns. The standard RISC OS 90 pixels per inch translates to (1/90Χ2.54Χ10,000) microns - 282. (Use -info to get information about the scaling, -nosize to stop it.)  Documentation from the "ST World" magazine's clinic. Apollo GPR 16-colour images ---------------------------  Recognised by &01000100 at the start of the file. RIX Softworks ColoRIX 8 bit per pixel files ------------------------------------------- Used by VGA Paint, image extension .SCE Œ .SCX. 4 or 8 bits per pixel.  Recognised by 'RIX3' at the start of the file.  Documentation never seen.  Only 5 files read; ChangeFSI checks to see if the header is the same as these files, and complains otherwise.  No resolution specified; equal to mode 27 assumed. TIFF pictures ------------- Frequently used by scanners, the Aldus/MicroSoft TIFF format is a common interchange format for graphics images on the Mac and PC (particularly DTP and Windows). It provides an arbitrary number of bits per pixel, size etc using a numeric tag scheme allowing new information to be introduced without upsetting existing programs. The format may be compressed (in 5 different ways at present). Details from Aldus UK, MicroSoft, Hewlett PackardŒ  Recognised by 'II' plus the 16 bit number 42 at the start of the file for little endian machines (ix86, ARM, VAXŒ)  Recognised by 'MM' plus the 16 bit number 42 at the start of the file for big endian machines (M680x0Œ)  Can read PackBits images and LZW compressed forms (at least the 3 it's seen so farŒ).  Cannot read predictor compressed LZW images.  So far ChangeFSI has only done 1, 4, 8 and 24 bit images. It can't read "planar" images or CCITT compressed forms.  Some TIFF images have incorrect pixel sizes: use -nosize if this is true. If no pixel size is specified, ChangeFSI assumes mode 27 size.  TIFF is a trademark of Aldus Corporation  Assigned RISC OS file type FF0; correctly typed files are recognised more quickly. UNIX rle format files --------------------- Used by a program called "svfb" to save the contents of large frame buffers; checked with four images at 24 bits per pixel.  Recognised by &CC52 at the start of the file.  No resolution specified; equal to mode 27 assumed. Portable Bit Map (pbm) binary encoded formats The "pbm" 'portable bitmap' file format --------------------------------------- Used by the "PBM-PLUS" toolkit (mainly Unix) by Jef Poskanzer. 1-24 bits per pixel (more can be specified in the format but ChangeFSI cannot read them). There are 3 types of format: black/white ('pbm'), grey ('pgm'), and colour ('ppm'); there are ASCII and binary encodings of each. ChangeFSI can read only the binary encoded formats (which use big-endian bytes), but for portability to other machines it can write the binary and ASCII encoded formats.  Recognised by 'P4', 'P5' or 'P6' at the start of the file.  Writable by ChangeFSI - first characters of file are: Binary ASCII (output only) black/white P4 P1 grey P5 P2 true colour P6 P3  No resolution specified; equal to mode 27 assumed. Files can be read with Jef Poskanzer's portable toolkit on other machines. The p2 format is easily convertible by programmers; it consists of: P2 # comment line xsize ysize maximum_value pixel_value pixel_value where all the numbers are in decimal (ASCII). 0 means black, maximum_value (=15) means white. The p3 format is similar with r, g, b triples for each pixel value. The number of bits per component (default 8) can be set from the command line with, for example, "p3,4" for 4 bits per component. ChangeFSI packed portable bitmaps ---------------------------------  Recognised by 'P15' at the start of the file.  Special packed output format. Binary pixel values, 5 bits per component, little endian RGB order packed into 16 bits. Header information as the other p formats. PocketBook I and II PIC format files ------------------------------------  Recognised by 'PIC' at the start of the file. Electronic Art's IFF ILBM pictures ---------------------------------- Provides an arbitrary sized image with up to 4096 colours, sometimes run length encoded. ChangeFSI understands the generic format and also the special Amiga format for "HAM" and "Half-bright" images.  Recognised by 'FORM' at the start of the file and 'ILBM' at offset 8 in file.  Only pixel aspect ratio specified, not its size (and then sometimes incorrectly): use -nosize *and* a size change (a:b) if it's wrong.  Images often small.  Doesn't understand Amiga "hires".  Can't convert HAM pictures directly to monochrome. MILLIPEDE PRISMA 8-bit colour images ------------------------------------ The Millipede Prisma 3 is a 768 pixels wide by 574 line interlaced display board for the Archimedes and BBC Microcomputer. It allows use of 256 colours from 2^24. Files may be stored uncompressed (432KBytes!) or run length encoded. This format is also used by CadSoft. More details from CadSoft or Millipede Electronic Graphics.  Recognised by 'MILLIPEDE' at offset 16 in file.  No resolution specified; equal to mode 27 assumed.  Slowish to read the compressed formats.  Scaling the picture using = can be poor, since 574 lines don't relate very well to 512 or 256. Use -info to display the scale ratios. MacPaint files -------------- Provides a 576 by 720 bitmap, run length coded by the Mac's "PackBits" algorithm (repeated bytes).  Recognised by 'PNTG' at offset 65 or 196 in the file. The former may only relate to files which have been through a program called "MacFix". Data assumed to start at position 128 in the file. Header ignored.  No resolution specified; equal to mode 25 assumed. MacPICT2 v2 8 and 24/32 bit per pixel) ---------------------------------------------- The PICT extended version 2 format provides an arbitary size packed picture, run length coded by the Mac's "PackBits" algorithm (repeated bytes).  Recognised by &00,&11,&02,&FF,&0C,&00,&FF,&FE (the PICT header) at offset 522 in the file.  Documentation available but mostly useless (it assumes you are about to call QuickDraw routines - "Note: for maximum safety and convenience, let QuickDraw generate and interpret your pictures." Apple fail to describe the PackBits algorithm in Inside MacŒ)  PICT is the loose equivalent of RISC OS Draw file format, but without the explicit sizing of objects - for PICT, if there is an object that you don't understand, there's no way of skipping it (whereas for Draw, the size of the object is specified in an object indep. way). Apple present a large table of the sizes of the objects (0000 - FFFF) which is not in ChangeFSI. Consequently, if ChangeFSI finds an object it doesn't know about before the picture, it stopsŒ  Only PackBitsRect (0098) (8bpp) and DirectBitsRect (009A) (24/32 bpp) are allowed.  ChangeFSI tries to skip a Clip (0001) region if it encounters it, since it is hard to get the Mac OS to make PICT files without a clip opcode in them.  Size of pixel specified.  Only 3 pictures read - since the format is very complicated (e.g. the size of things change if >250 rows in the picture!) this is no guarentee that anything else will be right. RT 24-bit run length coded IMAGE files -------------------------------------- Output from "RT", a private ray tracer by Brian D Watt(?). Arbitrary size in 2^24 colours, run length encoded.  Recognised by file being beneath a directory named IMAGE.  No resolution specified; equal to mode 27 assumed. PC EGA .DSP images ------------------ Experimentally determined that it holds a 640 by 350 EGA picture at 4 bits per pixel. ChangeFSI "knows" the default EGA palette (from IBM literature).  Recognised by file being beneath a directory named DSP, or the file's name ends /DSP.  Documentation never seen.  No resolution specified; equal to mode 27 assumed.  Only two examples read. Kodak RGB images, 24 bits per pixel -----------------------------------  Recognised by the file's name ending /RGB.