Man Linux: Main Page and Category List

NAME

       netpbm - package of graphics manipulation programs and libraries

DESCRIPTION

       Netpbm is a package of graphics programs and programming libraries.

       There are over 220 separate programs in the package, most of which have
       "pbm", "pgm", "ppm", or "pnm" in their names.   For  example,  pnmscale
       and giftopnm.

       For  example, you might use pnmscale to shrink an image by 10%.  Or use
       pnmcomp to overlay one image on top of  another.   Or  use  pbmtext  to
       create  an  image  of text.  Or reduce the number of colors in an image
       with pnmquant.

The Netpbm Formats

       All of the programs work with a set  of  graphics  formats  called  the
       "netpbm"  formats.   Specifically,  these  formats  are pbm(5), pgm(5),
       ppm(5), and pam(5).  The first  three  of  these  are  sometimes  known
       generically  as pnm.  Many of the Netpbm programs convert from a Netpbm
       format to another format or vice versa.  This is so  you  can  use  the
       Netpbm  programs  to work on graphics of any format.  It is also common
       to use a combination of Netpbm programs to convert from one  non-Netpbm
       format to another non-Netpbm format.  Netpbm has converters for over 80
       graphics formats, and as a package Netpbm lets  you  do  more  graphics
       format conversions than any other computer graphics facility.

       The  Netpbm formats are all raster formats, i.e. they describe an image
       as a matrix of rows and columns of pixels.   In  the  PBM  format,  the
       pixels  are  black  and white.  In the PGM format, pixels are shades of
       gray.  In the PPM format, the pixels are in full color.  The PAM format
       is  more  sophisticated.   A  replacement  for  all  three of the other
       formats, it can represent matrices of general data  including  but  not
       limited to black and white, grayscale, and color images.

       Programs  designed  to  work with PBM images have "pbm" in their names.
       Programs designed to work with PGM, PPM, and PAM images similarly  have
       "pgm", "ppm", and "pam" in their names.

       All  Netpbm  programs  designed to read PGM images see PBM images as if
       they were PGM too.  All Netpbm programs designed to read PPM images see
       PGM  and  PBM  images  as  if  they were PPM.  See the section "Implied
       Format Conversion" below.

       Programs that have "pnm" in their names read  PBM,  PGM,  and  PPM  but
       unlike "ppm" programs, they distinguish between them and their function
       depends on the format.  For example, pnmtogif creates a black and white
       GIF  output  image  if  its input is PBM or PGM, but a color GIF output
       image if its input is PPM.  And pnmscale produces an  output  image  of
       the  same format as the input.  A ppmscale program would read all three
       PNM input formats, but would see them  all  as  PPM  and  would  always
       generate PPM output.

       If  it  seems  wasteful  to  you to have three separate PNM formats, be
       aware that there is a historical reason  for  it.   In  the  beginning,
       there were only PBMs.  PGMs came later, and then PPMs.  Much later came
       PAM, which realizes  the  possibility  of  having  just  one  aggregate
       format.

       The  formats are described in the man pages pbm(5), pgm(5), ppm(5), and
       pam(5),

Implied Format Conversion

       A program that uses the PGM library to read an image  can  read  a  PBM
       image  as well as a PGM image.  The program sees the PBM image as if it
       were the equivalent PGM image, with a maxval of 255.

       A program that uses the PPM library to read an image  can  read  a  PGM
       image  as  well  as a PPM image and a PBM image as well as a PGM image.
       The program sees the PBM or PGM image as if it were the equivalent  PPM
       image,  with a maxval of 255 in the PBM case and the same maxval as the
       PGM in the PGM case.

Netpbm and Transparency

       In many graphics format, there’s a means  of  indicating  that  certain
       parts of the image are wholly or partially transparent, meaning that if
       it were displayed "over" another image,  the  other  image  would  show
       through there.  Netpbm formats deliberately omit that capability, since
       their purpose is to be extremely simple.

       In Netpbm, you  handle  transparency  via  a  transparency  mask  in  a
       separate  (slightly  redefined)  PGM  image.   In this pseudo-PGM, what
       would normally be a pixel’s  intensity  is  instead  it  an  opaqueness
       value.  See pgm(5).  pnmcomp is an example of a program that uses a PGM
       transparency mask.

The Netpbm Programs

       The Netpbm programs are generally useful run by a person from a command
       shell,  but  are  also  designed  to  be  used  by  programs.  A common
       characteristic of Netpbm programs is that they are simple,  fundamental
       building  blocks.   They  are  most powerful when stacked in pipelines.
       Netpbm programs do not use graphical user interfaces (in fact, none  of
       them  display  graphics  at all, except for a very simple Linux Svgalib
       displayer) and do not seek input from a user.

       Each of these programs has its own man page.

Common Options

       There are a few options that are present on all programs that are based
       on  the  Netpbm  libraries,  including  virtually  all Netpbm programs.
       These are not mentioned in the individual man pages for the programs.

       -quiet Suppress all informational  messages  that  would  otherwise  be
              issued  to  Standard  Error.  (To be precise, this only works to
              the extent that the program in question  implements  the  Netpbm
              convention   of  issuing  all  informational  messages  via  the
              pm_message() service of the Netpbm libraries).

       -version
              Instead of doing anything else, report the version of the libpbm
              library  linked  with  the  program  (it  may  have  been linked
              statically into the program, or dynamically linked at run time).
              Normally, the Netpbm programs and the libraries are installed at
              the same time, so this tells you the version of the program  and
              all the other Netpbm libraries and files it uses as well.

              Here  is  a  directory of the Netpbm programs.  You can also use
              man -k to search for a program that does what you want.

   Converters
       ppmtompeg
              convert series of PPM frames to an MPEG movie

       jpegtopnm
              convert JFIF/JPEG/EXIF file to Netpbm format

       pnmtojpeg
              convert PPM to JPEG/JFIF/EXIF format

       anytopnm
              convert any graphics format to Netpbm format

       bmptoppm
              convert Windows or OS/2 Bitmap file to PPM

       ppmtobmp
              convert PPM to Windows or OS/2 Bitmap file

       winicontoppm
              convert Windows icon file to PPM

       ppmtowinicon
              convert PPM to Windows icon file

       giftopnm
              convert GIF to portable anymap

       ppmtogif
              convert PPM to GIF

       pnmtopng
              convert Netpbm format to Portable Network Graphics

       pngtopnm
              convert PNG (Portable Network Graphics) to Netpbm formats

       palmtopnm
              convert Palm pixmap to Netpbm formats

       pnmtopalm
              convert Netpbm formats to Palm pixmap

       jbigtopbm
              convert JBIG BIE (compressed bitmap) to PBM

       pamtopnm
              convert a PAM image to PBM, PGM, or PPM

       pbmtojbig
              convert PBM to JBIG BIE (compressed bitmap)

       pnmtofiasco
              convert Netpbm image to Fiasco (wfa) highly compressed format

       fiascotopnm
              convert Fiasco (wfa) highly compressed format to Netpbm image

       hpcdtoppm
              convert photo CD to PPM

       pbmtonokia
              convert PBM to Nokia Smart Messaging Format (SMF)

       pbmtowbmp
              convert PBM to WAP (Wireless App Protocol) Wireless Bitmap

       wbmptopbm
              convert WAP (Wireless App Protocol) Wireless Bitmap to PBM

       neotoppm
              convert Atari Neochrome (.neo) image to PPM

       ppmtoneo
              convert PPM image to Atari Neochrome (.neo)

       pbmtomda
              convert from PBM to Microdesign (for Amstrad PCWs)

       mdatopbm
              convert from Microdesign (for Amstrad PCWs) to PBM

       atktopbm
              convert Andrew Toolkit raster object to PBM

       pbmtoatk
              convert PBM to Andrew Toolkit raster object

       brushtopbm
              convert Xerox doodle brushes to PBM

       cmuwmtopbm
              convert CMU window manager format to PBM

       g3topbm
              convert Group 3 FAX to PBM

       pbmtog3
              convert PBM to Group 3 FAX

       icontopbm
              convert Sun icon to PBM

       pbmtoicon
              convert PBM to Sun icon

       gemtopnm
              convert GEM .img format to PBM or pixmap

       macptopbm
              convert MacPaint to PBM

       pbmtomacp
              convert PBM to MacPaint

       mgrtopbm
              convert MGR format to PBM

       pbmtomgr
              convert PBM to MGR format

       pi3topbm
              convert Atari Degas .pi3 to PBM

       pbmtopi3
              convert PBM to Atari Degas .pi3

       xbmtopbm
              convert X10 or X11 bitmap to PBM

       pbmtoxbm
              convert PBM to X11 bitmap

       pbmtox10bm
              convert PBM to X10 bitmap

       ybmtopbm
              convert Bennet Yee "face" file into PBM

       pbmtoybm
              convert PBM into Bennet Yee "face" file

       pbmto10x
              convert PBM to Gemini 10x printer graphics

       pbmtoascii
              convert PBM to ASCII graphic form

       asciitopgm
              convert ASCII character graphics to PGM

       pbmtobbnbg
              convert PBM to BBN BitGraph graphics

       pbmtocmuwm
              convert PBM to CMU window manager format

       pbmtoepson
              convert PBM to Epson printer graphics

       pbmtogem
              convert PBM into GEM .img file

       pbmtogo
              convert PBM to GraphOn graphics

       pbmtolj
              convert PBM to HP LaserJet black and white graphics

       ppmtolj
              convert PPM to HP LaserJet color graphics (PCL)

       pjtoppm
              convert HP PaintJet file to PPM

       ppmtopj
              convert PPM to HP PaintJet file

       thinkjettopbm
              convert HP Thinkjet printer stream to PBM

       pbmtoplot
              convert PBM into Unix plot(5) file

       pbmtoptx
              convert PBM to Printronix graphics

       pbmtozinc
              convert PBM to Zinc Interface Library icon

       fitstopnm
              convert FITS format to portable anymap

       pnmtofits
              convert Netpbm formats to FITS format

       fstopgm
              convert Usenix FaceSaver(tm) format to PGM

       pgmtofs
              convert PGM to Usenix FaceSaver(tm) format

       hipstopgm
              convert HIPS format to PGM

       lispmtopgm
              convert a Lisp Machine bitmap file into PGM format

       pgmtolispm
              convert PGM into Lisp Machine format

       pnmtops
              convert Netpbm formats to Postscript

       pstopnm
              convert Postscript to Netpbm formats

       psidtopgm
              convert PostScript "image" data to PGM

       pbmtolps
              convert PBM image to Postscript using lines

       pbmtoepsi
              convert a PBM image to encapsulated Postscript preview bitmap

       pbmtopsg3
              convert PBM images to Postscript using G3 fax compression.

       rawtopgm
              convert raw grayscale bytes to PGM

       pgmtopbm
              convert PGM to PBM

       gouldtoppm
              convert Gould scanner file to PPM

       ilbmtoppm
              convert IFF ILBM to PPM

       ppmtoilbm
              convert PPM to IFF ILBM

       imgtoppm
              convert Img-whatnot to PPM

       mtvtoppm
              convert MTV ray-tracer output to PPM

       pcxtoppm
              convert PC Paintbrush format to PPM

       pgmtoppm
              colorize a portable graymap into a PPM

       pi1toppm
              convert Atari Degas .pi1 to PPM

       ppmtopi1
              convert PPM to Atari Degas .pi1

       picttoppm
              convert Macintosh PICT to PPM

       ppmtopict
              convert PPM to Macintosh PICT

       qrttoppm
              convert QRT ray-tracer output to PPM

       rawtoppm
              convert raw RGB bytes to PPM

       sldtoppm
              convert an AutoCAD slide file into a PPM

       spctoppm
              convert Atari compressed Spectrum to PPM

       sputoppm
              convert Atari uncompressed Spectrum to PPM

       tgatoppm
              convert TrueVision Targa file to PPM

       ppmtotga
              convert PPM to TrueVision Targa file

       ximtoppm
              convert Xim to PPM

       xpmtoppm
              convert XPM format to PPM

       ppmtoxpm
              convert PPM to XPM format

       yuvtoppm
              convert Abekas YUV format to PPM

       eyuvtoppm
              convert Encoder/Berkeley YUV format to PPM

       ppmtoeyuv
              convert PPM to Encoder/Berkeley YUV format

       ppmtoyuv
              convert PPM to Abekas YUV format

       ppmtoyuvsplit
              convert PPM to 3 subsampled raw YUV files

       yuvsplittoppm
              merge 3 subsampled raw YUV files to one PPM

       ppmtoacad
              convert PPM to AutoCAD database or slide

       ppmtoicr
              convert PPM to NCSA ICR graphics

       ppmtopcx
              convert PPM to PC Paintbrush format

       ppmtopgm
              convert PPM to portable graymap

       ppmtopuzz
              convert PPM to X11 "puzzle" file

       rasttopnm
              convert Sun raster file to Netpbm formats

       pnmtorast
              convert Netpbm formats to Sun raster file

       tifftopnm
              convert TIFF file to portable anymap

       pnmtotiff
              convert Netpbm formats to TIFF RGB file

       pnmtotiffcmyk
              convert Netpbm formats to TIFF CMYK file

       xwdtopnm
              convert X10 or X11 window dump to Netpbm formats

       pnmtoxwd
              convert Netpbm formats to X11 window dump

       pnmtoplainpnm
              convert regular Netpbm format image into plain Netpbm format

       pbmtopgm
              convert PBM file to PGM by averaging areas

       411toppm
              convert 411 (Sony Mavica) to PPM

       ppmtosixel
              convert PPM to DEC sixel format

       ppmtouil
              convert PPM to Motif UIL icon file

       sbigtopgm
              convert Santa Barbara Instrument Group CCD file to PGM

       vidtoppm
              convert Parallax XVideo JPEG to sequence of PPM files

       pnmtorle
              convert PNM to Utah Raster Toolkit (urt/rle) file

       rletopnm
              convert Utah Raster Toolkit (urt/rle) file to PNM

       ppmtoleaf
              convert PPM to Interleaf

       leaftoppm
              convert Interleaf to PPM

       bioradtopgm
              convert Biorad confocal image to PGM

       pbmtoln03
              convert PGM image to Dec LN03+ Sixel image

       pbmtopk
              convert PBM image to packed format (PK) font

       pktopbm
              convert packed format (PK) font to PBM image

   Image Generators
       All of these generate Netpbm format output.

       pbmmake
              create a blank PBM image of a specified size

       ppmmake
              create a PPM image of a specified size and color

       pgmramp
              generate a grayscale ramp

       ppmpat create a pretty PPM image

       ppmrainbow
              create a spectrum-like image with colors fading together.

       pgmnoise
              create a PGM image of white noise

       pbmtext
              render text into a PBM image

       pbmupc create a Universal Product Code PBM image

       ppmcie generate a CIE color map PPM image

       pbmpage
              create a printer test pattern page in PBM format

       ppmcolors
              create a color map (PPM image) containing all possible colors of
              given maxval

   Image Editors
       All of these work on the Netpbm formats

       ppmlabel
              Add text to an image

       pnmshadow
              add a shadow to an image so it looks like it’s floating

       ppmbrighten
              brighten or dim an image -- change saturation and value

       ppmdim dim an image - different way from ppmbrighten

       pbmreduce
              reduce a PBM N times, using Floyd-Steinberg

       pgmnorm
              normalize contrast in a PGM image

       ppmnorm
              normalize contrast in a PPM image

       pbmpscale
              enlarge a PBM image with edge smoothing

       pnmscale
              scale an image with high precision

       pnmscalefixed
              scale an image quickly with low precision

       pnmenlarge
              enlarge an image N times

       ppmdither
              ordered dither for color images

       pnmcolormap
              Choose  the  N  best  colors  to  represent  an  image; create a
              colormap

       pnmremap
              Replace colors in an image with those from a color map

       ppmquant
              quantize colors in a color image down to fewer colors

       pnmquant
              quantize colors/shades in a color or  grayscale  image  down  to
              fewer

       ppmquantall
              quantize colors on many files

       ppmrelief
              run a Laplacian Relief filter on a PPM

       pnmarith
              perform arithmetic on two images

       pnmcat concatenate images

       pnmpad add borders to an image

       pnmcomp
              create composite (overlay) of images

       ppmmix mix (overlay) two images.

       pnmcrop
              crop all like-colored borders off an image

       pamcut select a rectangular region from an image

       pnmcut obsolete version of pamcut (kept because it may have fewer bugs)

       pamdice
              slice an image into many horizontally and/or vertically

       pamdeinterlace
              remove every other row from an image

       pamchannel
              extract a single plane (channel, e.g. R, G, or B) from an image

       pnmdepth
              change the maxval in an image

       pnmflip
              perform one or more flip operations on an image

       pamstretch
              scale up an image by inserting interpolated pixels

       pamstretch-gen
              scale by non-integer values using pamstretch and pnmscale

       pnminvert
              invert an image

       pnmgamma
              perform gamma correction on an image

       pnmhisteq
              histogram equalize image to increase contrast

       pnmmargin
              add a margin to an image

       pnmpaste
              paste a rectangle into an image

       pnmrotate
              rotate an image

       pnmshear
              shear an image

       pnmsmooth
              smooth am image

       pnmtile
              replicate an image into a specified size

       pbmclean
              remove lone pixels (snow) from a PBM image

       pnmalias
              antialias an image

       ppmchange
              change all of one color to another in PPM image

       pnmnlfilt
              filter an image by replacing  each  pixel  with  a  function  of
              nearby pixels

       ppmshift
              shift lines of PPM image left or right a random amount

       ppmspread
              move pixels of PPM image a random amount

       pnmconvol
              general MxN convolution on an image

       rgb3toppm
              combine three portable graymaps into one PPM

       ppmtorgb3
              separate a PPM into three portable graymaps

       pbmlife
              apply Conway’s rules of Life to a PBM image

       ppmdist
              map colors to high contrast grayscales arbitrarily

       ppmntsc
              adjust colors so they are legal for NTSC or PAL television

   Image Analyzers
       These all work on the Netpbm formats as input.

       pnmfile
              describe an image’s vital characteristics

       pnmpsnr
              measure difference between two images

       pgmedge
              edge-detect a PGM image

       pgmenhance
              edge-enhance a PGM image

       pgmslice
              print grayscale values for a row or column of a PGM image

       pgmtexture
              calculate textural features on a PGM image

       pgmhist
              print a histogram of the values in a PGM image

       ppmhist
              print a histogram of a PPM

       pnmhistmap
              draw a histogram of a PGM or PPM

       ppmtomap
              generate a map of all colors in an image

       ppm3d  generate a blue/green 3D glasses image from two images

   Miscellaneous
       ppmsvgalib
              display a PPM image on a Linux virtual console using Svgalib

       pbmmask
              create a mask bitmap from a regular bitmap

       ppmcolormask
              create mask of areas of a certain color in an image

       pnmsplit
              split a multi-image Netpbm file into multiple 1-image files

       pnmindex
              build a visual index of a bunch of Netpbm images

       pcdindex
              build a visual index of a photo CD from PCD overview file

       pnmmontage
              build multiple Netpbm images into a single montage image

       pgmbentley
              Bentleyize a PGM image

       pgmcrater
              create cratered terrain by fractal forgery

       pamoil turn a PNM or PAM image into an oil painting

       ppmforge
              fractal forgeries of clouds, planets, and starry skies

       pgmkernel
              generate a convolution kernel

       ppmtv  Make an image lined so it looks like an old TV

       pbmto4425
              Display PBM image on AT&T 4425 ASCII terminal with gfx chars

   Uncatalogued As Yet
       pnmtoddif

       pnmtosgi

       pnmtosir

       ppmflash

       ppmqvga

       ppmtomitsu

       ppmtopjxl

       sgitopnm

       sirtopnm

       spottopgm

       xvminitoppm

       zeisstopnm

The Netpbm Libraries

       The  Netpbm programming libraries, libpbm(3), libpgm(3), libppm(3), and
       libpnm(3), make it easy  to  write  programs  that  manipulate  graphic
       images.   Their  main function is to read and write files in the Netpbm
       format, and because the Netpbm package contains converters for all  the
       popular  graphics  formats, if your program reads and writes the Netpbm
       formats, you can use it with any formats.

       But  the  libraries  also  contain  some  utility  functions,  such  as
       character drawing and RGB/YCrCb conversion.

       The  libraries have the conventional C linkage.  Virtually all programs
       in the Netpbm package are based on the Netpbm libraries.

   Application Notes
       As a collection of primitive tools, the power of Netpbm  is  multiplied
       by  the power of all the other unix tools you can use with them.  These
       notes remind you of some of the more useful ways to  do  this.   Often,
       when  people want to add high level functions to the Netpbm tools, they
       have overlooked some existing tool that, in  combination  with  Netpbm,
       already does it.

       Often,  you  need  to apply some conversion or edit to a whole bunch of
       files.

       As a rule, Netpbm programs take one input file and produce  one  output
       file,  usually  on Standard Output.  This is for flexibility, since you
       so often have to pipeline many tools together.

       Here is an example of a shell command to convert all your of PNG  files
       (named *.png) to JPEG files named *.jpg:

       for  i  in  *.png;  do pngtopnm $i | ppmtojpeg >basename $i .png.jpg;
       done

       Or you might just generate a stream of individual shell  commands,  one
       per  file, with awk or perl.  Here’s how to brighten 30 YUV images that
       make up one second of a movie, keeping the images in the same files:

       ls *.yuv .br | perl -nechomp;
       print yuvtoppm $_ | ppmbrighten -v 100 | ppmtoyuv >tmp$$.yuv; ,
       mv tmp$$.yuv $_0.br | sh

       The tools find (with the -exec option) and xargs are  also  useful  for
       simple manipulation of groups of files.

       Some  shells’  "process  substitution"  facility  can help where a non-
       Netpbm program expects you to identify a disk file for  input  and  you
       want  it  to  use  the  result of a Netpbm manipulation.  Say printcmyk
       takes the filename of a Tiff CMYK file as input and what you have is  a
       PNG file abc.png.  Try:

       printcmyk <({ pngtopnm abc.png | pnmtotiffcmyk ; })

       It  works  in the other direction too, if you have a program that makes
       you name its output file and you want the output to go through a Netpbm
       tool.

   Other Graphics Software
       Netpbm  contains  primitive  building  blocks.   It  certainly is not a
       complete graphics library.

       The first thing you will need to make use of any of these  tools  is  a
       viewer.     For    the    X    inclined,    there    is    xzgv.    See
       ftp://metalab.unc.edu/pub/Linux/apps/graphics/viewers/X.

       xloadimage and its extension xli are also  common  ways  to  display  a
       graphic image in X.

       ImageMagick  is  like  a  visual version of Netpbm.  Using the X/Window
       system on Unix, you can do basic editing of images and lots  of  format
       conversions.   The package does include at least some non-visual tools.
       Convert, Mogrify, Montage, and Animate are popular  programs  from  the
       ImageMagick  package.   ImageMagick  runs on Unix, Windows, Windows NT,
       Macintosh, and VMS.

       The Gimp is a visual image editor for Unix and X, in the same  category
       as  the  more  famous,  less  capable,  and  much  more expensive Adobe
       Photoshop, etc. for Windows.  See http://www.gimp.org.

       The file program looks at a file and tells you what kind of file it is.
       It  recognizes most of the graphics formats with which Netpbm deals, so
       it is pretty  handy  for  graphics  work.   Netpbm’s  anytopnm  program
       depends on file.  See ftp://ftp.astron.com/pub/file.

       The Utah Raster Toolkit serves a lot of the same purpose as Netpbm, but
       without the emphasis on format conversions.  This package is  based  on
       the  RLE  format, which you can convert to and from the Netpbm formats.
       http://www.cs.utah.edu/research/projects/alpha1/urt.html   gives   some
       information  on the Utah Raster Toolkit, but does not tell where to get
       it.

       There are some Netpbm-like graphics tools distributed by the Army  High
       Performance  Computing  Research  Center at http://www.arc.umn.edu/gvl-
       software/media-tools.html.  These operate directly on non-Netpbm format
       images,  so  they  aren’t included in the Netpbm package.  However, you
       can use  them  with  any  image  format  by  using  the  Netpbm  format
       converters.

       Ivtools  is  a  suite of free X Windows drawing editors for Postscript,
       Tex, and  web  graphics  production,  as  well  as  an  embeddable  and
       extendable  vector  graphic shell.  It uses the Netpbm facilities.  See
       http://www.ivtools.org.

       Ilib is a C subroutine library with functions for  adding  text  to  an
       image  (as you might do at a higher level with pbmtext, pnmcomp, etc.).
       It   works   with   Netpbm   input   and   output.     Find    it    at
       http://www.radix.net/~cknudsen/Ilib.   Netpbm  also  includes character
       drawing functions in the libppm library, but they do not have as  fancy
       font  capabilities  (see  ppmlabel  for an example of use of the Netpbm
       character drawing functions).

       GD is a library of graphics routines that is part of  PHP.   It  has  a
       subset  of  Netpbm’s functions and has been found to resize images more
       slowly and with less quality.

       pnm2ppa converts to HP’s "Winprinter" format (for  HP  710,  720,  820,
       1000,  etc).   It  is  a  superset  of  Netpbm’s  pbmtoppa and handles,
       notably, color.  However, it is more of a printer driver than a Netpbm-
       style       primitive      graphics      building      block.       See
       http://sourceforge.net/project/?group_id=1322.

       The program morph morphs one image into another.  It uses Targa  format
       images, but you can use tgatoppm and ppmtotga to deal with that format.
       You have to use the graphical (X/Tk) Xmorph to create  the  mesh  files
       that you must feed to morph.  morph is part of the Xmorph package.  See
       http://www.colorado-research.com/~gourlay/software/Graphics/Xmorph.

       To create an animated GIF, or extract a frame from one,  use  gifsicle.
       gifsicle  converts  between animated GIF and still GIF, and you can use
       ppmtogif and giftopnm to connect up to all the Netpbm  utilities.   See
       http://www.lcdf.org/gifsicle.

       To  convert  an  image of text to text (optical character recongition -
       OCR),  use  gocr  (think  of  it  as  an  inverse  of  pbmtext).    See
       http://altmark.nat.uni-magdeburg.de/~jschulen/ocr/.

       http://schaik.com/pngsuite  contains  a PNG test suite -- a whole bunch
       of PNG images exploiting the various features of the PNG format.

       Another      version       of       pnmtopng/pngtopnm       is       at
       http://www.schaik.com/png/pnmtopng.html.   The  version  in  Netpbm was
       actually based on that package a long time ago, and you can  expect  to
       find   better   exploitation  of  the  PNG  format,  especially  recent
       enhancements, in that package.  It may be a little less consistent with
       the  Netpbm  project  and  less  exploitive  of  recent  Netpbm  format
       enhancements, though.

       jpegtran Does some of the same transformations as Netpbm is famous for,
       but  does them specifically on JPEG files and does them without loss of
       information.  By contrast, if you were to use Netpbm, you  would  first
       decompress  the  JPEG image to Netpbm format, then transform the image,
       then compress it back to JPEG format.  In that recompression, you  lose
       a  little  image  information  because  JPEG  is  a  lossy compression.
       jpegtran comes with the Independent Jpeg  Group’s  (http://www.ijg.org)
       JPEG library.

       Some  tools  to  deal  with EXIF files (see also Netpbm’s jpegtopnm and
       pnmtojpeg):   To   dump   (interpret)   an   EXIF   header:    Exifdump
       ((http://topo.math.u-psud.fr/~bousch/exifdump.py)        or       Jhead
       (http://www.sentex.net/~mwandel/jhead).

       A Python EXIF library and dumper:  http://pyexif.sourceforge.net.

       Latex2html converts Latex document  source  to  HTML  document  source.
       Part  of  that  involves graphics, and Latex2html uses Netpbm tools for
       some of that.  But Latex2html through its history has had  some  rather
       esoteric  codependencies  with  Netpbm.   Older Latex2html doesn’t work
       with current Netpbm.  Latex2html-99.2beta8 works, though.

   Other Graphics Formats
       People never seem to tire of  inventing  new  graphics  formats,  often
       completely  redundant  with  pre-existing  ones.  Netpbm cannot keep up
       with them.  Here is a list of a few that we know Netpbm does not handle
       (yet).

         CAL  (originated by US Department Of Defense, favored by architects).
       http://www.landfield.com/faqs/graphics/fileformats-
       faq/part3/section-.html

         array formats dx, general, netcdf, CDF, hdf, cm

         CGM+

         Windows  Meta  File  (.WMF).  Libwmf converts from WMF to things like
       Latex, PDF, PNG.  Some of these can be input to Netpbm.

         Microsoft Word, RTF.  Microsoft keeps a  proprietary  hold  on  these
       formats.   Any  software you see that can handle them is likely to cost
       money.

         DXF (AutoCAD)

HISTORY

       Netpbm has a  long  history,  starting  with  Jef  Poskanzer’s  Pbmplus
       package in 1988.  The file HISTORY in the Netpbm source code contains a
       historical overview as well as a detailed history release by release.

AUTHOR

       Netpbm is  based  on  the  Pbmplus  package  by  Jef  Poskanzer,  first
       distributed  in 1988 and maintained by him until 1991.  But the package
       contains work by countless other authors, added  since  Jef’s  original
       work.   In  fact,  the  name is derived from the fact that the work was
       contributed by people all over the world via the  Internet,  when  such
       collaboration  was still novel enough to merit naming the package after
       it.

       Bryan Henderson has been maintaining Netpbm since 1999.  In addition to
       packaging  work  by others, Bryan has also written a significant amount
       of new material for the package.

                                                                     netpbm(1)