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MIFF(4)			   Kernel Interfaces Manual		       MIFF(4)

       MIFF - Magick Image File	Format

       #include	<image.h>

       The Magick Image	File Format (MIFF) is a	platform-independent format
       for storing bitmap images.  MIFF	is a part of the ImageMagick toolkit
       of image	manipulation utilities for the X Window	System.	 ImageMagick
       is capable of converting	many different image file formats to and from
       MIFF (e.g. JPEG,	XPM, TIFF, etc.).

       A MIFF image file consist of two	sections.  The first section is	a
       header composed of keys describing the image in text form.  The next
       section is the binary image data.  The header is	separated from the im-
       age data	by a : character immediately followed by a newline.

       The MIFF	header is composed entirely of LATIN-1 characters.  The	fields
       in the header are key and value combination in the key=value format,
       with each key and value separated by an equal sign (=).	Each key=value
       combination is delimited	by at least one	control	or whitespace charac-
       ter.  Comments may appear in the	header section and are always delim-
       ited by braces.	The MIFF header	always ends with a colon (:) charac-
       ter, followed by	a ctrl-Z character.  It	is also	common to proceed the
       colon with a formfeed and a newline character.  The formfeed prevents
       the listing of binary data when using more(1) under Unix	where the
       ctrl-Z has the same effect with the type	command	on the Win32 command

       The following is	a list of key=value combinations that may be found in
       a MIFF file:

	      border-color=color matte-color=color these optional keys re-
	      flects the image background, border, and matte colors respec-
	      tively. A	color can be a name (e.g. white) or a hex value	(e.g.

	      class=PseudoClass	the type of binary image data stored in	the
	      MIFF file.  If this key is not present, DirectClass image	data
	      is assumed.

	      the number of colors in a	DirectClass image. For a PseudoClass
	      image, this key specifies	the size of the	colormap.  If this key
	      is not present in	the header, and	the image is PseudoClass, a
	      linear 256 color grayscale colormap is used with the image data.
	      The maximum number of colormap entries is	65535.	col-
	      orspace=CMYK the colorspace of the pixel data.  The default is

	      the width	of the image in	pixels.	 This is a required key	and
	      has no default.

	      compression=Fax compression=JPEG compression=LZW compression=RLE
	      compression=Zip the type of algorithm used to compress the image
	      data.  If	this key is not	present, the image data	is assumed to
	      be uncompressed.

       delay _1/100ths of a second_
	      the interframe delay in an image sequence.  The maximum delay is

	      depth=16 the depth of a single color value representing values
	      from 0 to	255 (depth 8) or 65535 (depth 16).  If this key	is ab-
	      sent, a depth of 8 is assumed.

       dispose value
	      GIF disposal method.

	      Here are the valid methods:

		   0  No disposal specified.
		   1  Do not dispose between frames.
		   2  Overwrite	frame with background color from header.
		   3  Overwrite	with previous frame.

	      the gamma	of the image.  If it is	not specified, a gamma of 1.0
	      (linear brightness response) is assumed,

	      identifies the file as a MIFF-format image file.	This key is
	      required and has no default.  Although this key can appear any-
	      where in the header, it should start as the first	key of the
	      header in	column 1.  This	will allow programs like file(1) to
	      easily identify the file as MIFF.

       iterations value
	      the number of times an image sequence loops before stopping.

	      defines a	short title or caption for the image.  If any white-
	      space appears in the label, it must be enclosed within braces.

	      matte=False specifies whether a DirectClass image	has matte
	      data.  Matte data	is generally useful for	image compositing.
	      This key has no meaning for pseudo-color images.

       montage=_width_x_height_{+-}_x offset_{+-}_y offset_
	      size and location	of the individual tiles	of a composite image.
	      See X(1) for details about the geometry specification.

	      Use this key when	the image is a composite of a number of	dif-
	      ferent tiles.  A tile consists of	an image and optionally	a bor-
	      der and a	label.	_width_	is the size in pixels of each individ-
	      ual tile in the horizontal direction and _height_	is the size in
	      the vertical direction.  Each tile must have an equal number of
	      pixels in	width and equal	in height.  However, the width can
	      differ from the height.  _x offset_ is the offset	in number of
	      pixels from the vertical edge of the composite image where the
	      first tile of a row begins and _y	offset_	is the offset from the
	      horizontal edge where the	first tile of a	column begins.

	      If this key is specified,	a directory of tile names must follow
	      the image	header.	 The format of the directory is	explained be-

	      preferred	size and location of an	image canvas.

	      the number of bytes in the International Color Consortium	color
	      profile.	The profile is defined by the ICC profile specifica-
	      tion located at


	      green-primary=x,y	blue-primary=x,y white-point=x,y this optional
	      key reflects the chromaticity primaries and white	point.

	      rendering-intent=perceptual rendering-intent=absolute rendering-
	      intent=relative Rendering	intent is the CSS-1 property that has
	      been defined by the International	Color Consortium

	      vertical and horizontal resolution of the	image.	See units for
	      the specific resolution units (e.g. pixels per inch).

	      the height of the	image in pixels.  This is a required key and
	      has no default.

	      the sequence number for this MIFF	image file.  This optional key
	      is used when a MIFF image	file is	one in a sequence of files
	      used in an animation.

	      this optional key	contains a string that uniquely	identifies the
	      image pixel contents.  NIST's SHA-256 message digest algorithm
	      is recommended.

	      units=pixels-per-centimeter image	resolution units.

	      Other key	value pairs are	permitted.  If a value contains	white-
	      space it must be enclosed	with braces as illustrated here:

		  class=PseudoClass  colors=256
		  compression=RunlengthEncoded	packets=27601
		  columns=1280	rows=1024
		  copyright={Copyright (c) 2001	ImageMagick Studio}

       Note that key=value combinations	may be separated by newlines or	spaces
       and may occur in	any order within the header.  Comments (within braces)
       may appear anywhere before the colon.

       If you specify the montage key in the header, follow the	header with a
       directory of image tiles.  This directory consists of a name for	each
       tile of the composite image separated by	a newline character.  The list
       is terminated with a NULL character.

       If you specify the color-profile	key in the header, follow the header
       (or montage directory if	the montage key	is in the header) with the bi-
       nary color profile.

       Next comes the binary image data	itself.	 How the image data is format-
       ted depends upon	the class of the image as specified (or	not specified)
       by the value of the class key in	the header.

       DirectClass images (class=DirectClass) are continuous-tone, images
       stored as RGB (red, green, blue), RGBA (red, green, blue, alpha), or
       CMYK (cyan, yellow, magenta, black) intensity values as defined by the
       colorspace key. Each intensity value is one byte	in length for images
       of depth	8 (0..255), whereas, images of depth 16	(0..65535) require two
       bytes in	most significant byte first order.

       PseudoClass images (class=PseudoClass) are colormapped RGB images. The
       colormap	is stored as a series of red, green, and blue pixel values,
       each value being	a byte in size.	If the image depth is 16, each col-
       ormap entry consumes two	bytes with the most significant	byte being
       first. The number of colormap entries is	defined	by the colors key.
       The colormap data occurs	immediately following the header (or image di-
       rectory if the montage key is in	the header). PseudoClass image data is
       an array	of index values	into the color map. If there are 256 or	fewer
       colors in the image, each byte of image data contains an	index value.
       If the image contains more than 256 colors or the image depth is	16,
       the index value is stored as two	contiguous bytes with the most signif-
       icant byte being	first. If matte	is true, each colormap index is	fol-
       lowed by	a 1 or 2-byte alpha value.

       The image data in a MIFF	file may be uncompressed, runlength encoded,
       Zip compressed, or BZip compressed. The compression key in the header
       defines how the image data is compressed. Uncompressed pixels are just
       stored one scanline at a	time in	row order. Runlength encoded compres-
       sion counts runs	of identical adjacent pixels and stores	the pixels
       followed	by a length byte (the number of	identical pixels minus 1). Zip
       and BZip	compression compresses each row	of an image and	preceeds the
       compressed row with the length of compressed pixel bytes	as a word in
       most significant	byte first order.

       MIFF files may contain more than	one image.  Simply concatenate each
       individual image	(composed of a header and image	data) into one file.

       display(1), animate(1), import(1), montage(1), mogrify(1), convert(1),
       more(1),	compress(1)

       Copyright (C) 2000 ImageMagick Studio, a	non-profit organization	dedi-
       cated to	making software	imaging	solutions freely available.

       Permission is hereby granted, free of charge, to	any person obtaining a
       copy of this software and associated documentation files	("Image-
       Magick"), to deal in ImageMagick	without	restriction, including without
       limitation the rights to	use, copy, modify, merge, publish, distribute,
       sublicense, and/or sell copies of ImageMagick, and to permit persons to
       whom the	ImageMagick is furnished to do so, subject to the following

       The above copyright notice and this permission notice shall be included
       in all copies or	substantial portions of	ImageMagick.

       The software is provided	"as is", without warranty of any kind, express
       or implied, including but not limited to	the warranties of mer-
       chantability, fitness for a particular purpose and noninfringement.  In
       no event	shall ImageMagick Studio be liable for any claim, damages or
       other liability,	whether	in an action of	contract, tort or otherwise,
       arising from, out of or in connection with ImageMagick or the use or
       other dealings in ImageMagick.

       Except as contained in this notice, the name of the ImageMagick Studio
       shall not be used in advertising	or otherwise to	promote	the sale, use
       or other	dealings in ImageMagick	without	prior written authorization
       from the	ImageMagick Studio.

       John Cristy, ImageMagick	Studio

ImageMagick			    $Date$			       MIFF(4)


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