4:miff

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      #include <image.h>

Contents

NAME

      MIFF - Magick Image File Format 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 con-
      verting many different image file formats to and from MIFF (e.g. JPEG, XPM, TIFF, etc.).

DESCRIPTION

      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 image 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 combina-
      tion 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 character.  Comments may appear in the header section and are
      always delimited by braces.  The MIFF header always ends with a colon (:) character, followed by a ctrl-Z charac-
      ter.  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 line.
 
      The following is a list of key=value combinations that may be found in a MIFF file:
 
      background-color=color
             border-color=color matte-color=color these optional keys reflects the image background, border, and matte
             colors respectively. A color can be a name (e.g. white) or a hex value (e.g. #ccc).
 
      class=DirectClass
             class=PseudoClass the type of binary image data stored in the MIFF file.  If this key is not present,
             DirectClass image data is assumed.
 
      colors=value
             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 RGB.
 
      columns=value
             the width of the image in pixels.  This is a required key and has no default.
 
      compression=BZip
             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 uncom-
             pressed.
 
      delay <1/100ths of a second>
             the interframe delay in an image sequence.  The maximum delay is 65535.
 
      depth=8
             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 absent, 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.
 
      gamma=value
             the gamma of the image.  If it is not specified, a gamma of 1.0 (linear brightness response) is assumed,
 
      id=ImageMagick
             identifies the file as a MIFF-format image file.  This key is required and has no default.  Although this
             key can appear anywhere 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.
 
      label={value}
             defines a short title or caption for the image.  If any whitespace appears in the label, it must be
             enclosed within braces.
 
      matte=True
             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 different tiles.  A tile consists of an image
             and optionally a border and a label.  <width> is the size in pixels of each individual tile in the hori-
             zontal 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 below.
 
      page=value
             preferred size and location of an image canvas.
 
      profile-icc=value
             the number of bytes in the International Color Consortium color profile.  The profile is defined by the
             ICC profile specification located at ftp://sgigate.sgi.com/pub/icc/icc34.ps.
 
      colorspace=RGB
 
      red-primary=x,y
             green-primary=x,y blue-primary=x,y white-point=x,y this optional key reflects the chromaticity primaries
             and white point.
 
      rendering-intent=saturation
             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 (http://www.color.org).
 
      resolution=<x-resolution>x<y-resolution>
             vertical and horizontal resolution of the image.  See units for the specific resolution units (e.g. pixels
             per inch).
 
      rows=value
             the height of the image in pixels.  This is a required key and has no default.
 
      scene=value
             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.
 
      signature=value
             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-inch
             units=pixels-per-centimeter image resolution units.
 
             Other key value pairs are permitted.  If a value contains whitespace it must be enclosed with braces as
             illustrated here:
 
                 id=ImageMagick
                 class=PseudoClass  colors=256
                 compression=RunlengthEncoded  packets=27601
                 columns=1280  rows=1024
                 signature=d79e1c308aa5bbcdeea8ed63df412da9
                 copyright={Copyright (c) 2001 ImageMagick Studio}
                 <FF>
                 :
 
      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 binary color profile.
 
      Next comes the binary image data itself.  How the image data is formatted 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 colormap entry con-
      sumes two bytes with the most significant byte being first. The number of colormap entries is defined by the col-
      ors key.  The colormap data occurs immediately following the header (or image directory 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 significant byte being
      first. If matte is true, each colormap index is followed 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 compression 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.

RELATED

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

COPYRIGHT

      Copyright (C) 2000 ImageMagick Studio, a non-profit organization dedicated 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 doc-
      umentation files ("ImageMagick"), 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 conditions:
 
      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 merchantability, 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 other-
      wise to promote the sale, use or other dealings in ImageMagick without prior written authorization from the
      ImageMagick Studio.

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