"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">\r
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en" dir="ltr">\r
<head>\r
- <meta http-equiv="content-type" content="text/html; charset=UTF-8"/>\r
- <meta name="verify-v1" content="g222frIIxcQTrvDR3NBRUSKP3AnMNoqxOkIniCEkV7U=" />\r
- <link rel="meta" type="application/rdf+xml" title="ICI" href="http://imagemagick.org/ici.rdf" />\r
- <style type="text/css" media="screen,projection"><!--\r
- @import url("../www/magick.css");\r
- --></style>\r
- <link rel="shortcut icon" href="../images/wand.ico" type="images/vnd.microsoft.icon"/>
- <title>ImageMagick: Encipher or Decipher an Image</title>
+ <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>\r
+ <meta name="verify-v1" content="g222frIIxcQTrvDR3NBRUSKP3AnMNoqxOkIniCEkV7U="/>\r
+ <title>ImageMagick: Encipher or Decipher an Image</title/>
<meta http-equiv="Content-Language" content="en-US"/>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<meta http-equiv="Reply-to" content="magick-users@imagemagick.org"/>
+ <meta name="Application-name" content="ImageMagick"/>
+ <meta name="Description" content="ImageMagick® is a software suite to create, edit, and compose bitmap images. It can read, convert and write images in a variety of formats (about 100) including GIF, JPEG, JPEG-2000, PNG, PDF, PhotoCD, TIFF, and DPX. Use ImageMagick to translate, flip, mirror, rotate, scale, shear and transform images, adjust image colors, apply various special effects, or draw text, lines, polygons, ellipses and Bézier curves. ImageMagick is free software delivered as a ready-to-run binary distribution or as source code that you can freely use, copy, modify, and distribute. Its license is compatible with the GPL. It runs on all major operating systems. The functionality of ImageMagick is typically utilized from the command line or you can use the features from programs written in your favorite programming language. Choose from these interfaces: MagickCore (C), MagickWand (C), ChMagick (Ch), Magick++ (C++), JMagick (Java), L-Magick (Lisp), PascalMagick (Pascal), PerlMagick (Perl), MagickWand for PHP (PHP), PythonMagick (Python), RMagick (Ruby), or TclMagick (Tcl/TK). With a language interface, use ImageMagick to modify or create images automagically and dynamically."/>
+ <meta name="Application-url" content="http://www.imagemagick.org"/>
<meta name="Generator" content="PHP"/>
<meta name="Keywords" content="encipher, or, decipher, an, image, ImageMagick, ImageMagic, MagickCore, MagickWand, PerlMagick, Magick++, RMagick, PythonMagick, JMagick, TclMagick, Image, Magick, Magic, Wand, ImageMagickObject, Swiss, Army, Knife, Image, Processing"/>
- <meta name="Description" content="ImageMagick® is a software suite to create, edit, and compose bitmap images. It can read, convert and write images in a variety of formats (about 100) including GIF, JPEG, JPEG-2000, PNG, PDF, PhotoCD, TIFF, and DPX. Use ImageMagick to translate, flip, mirror, rotate, scale, shear and transform images, adjust image colors, apply various special effects, or draw text, lines, polygons, ellipses and Bézier curves. ImageMagick is free software delivered as a ready-to-run binary distribution or as source code that you can freely use, copy, modify, and distribute. Its license is compatible with the GPL. It runs on all major operating systems. The functionality of ImageMagick is typically utilized from the command line or you can use the features from programs written in your favorite programming language. Choose from these interfaces: MagickCore (C), MagickWand (C), ChMagick (Ch), Magick++ (C++), JMagick (Java), L-Magick (Lisp), PascalMagick (Pascal), PerlMagick (Perl), MagickWand for PHP (PHP), PythonMagick (Python), RMagick (Ruby), or TclMagick (Tcl/TK). With a language interface, use ImageMagick to modify or create images automagically and dynamically."/>
<meta name="Rating" content="GENERAL"/>
<meta name="Robots" content="INDEX, FOLLOW"/>
<meta name="Generator" content="ImageMagick Studio LLC"/>
<meta name="Resource-type" content="document"/>
<meta name="Copyright" content="Copyright (c) 1999-2010 ImageMagick Studio LLC"/>
<meta name="Distribution" content="Global"/>
+ <link rel="icon" href="../images/wand.png" sizes="32x32"/>
+ <link rel="shortcut icon" href="../images/wand.ico" type="images/x-icon"/>
+ <link rel="meta" type="application/rdf+xml" title="ICI" href="http://imagemagick.org/ici.rdf"/>\r
+ <style type="text/css" media="all">\r
+ @import url("../www/magick.css");\r
+ </style>\r
</head>\r
\r
<body id="www-imagemagick-org">\r
style="width: 114px; height: 118px; border: 0px; float: right;" /></a>\r
</div>\r
\r
-<div class="eastbar">\r
+<div class="westbar">\r
\r
<div class="menu">
- <a href="../index.html">About ImageMagick</a>
+ <a title="About ImageMagick" href="../index.html">About ImageMagick</a>
</div>
<div class="sep"></div>\r
<div class="menu">
- <a href="../www/command-line-tools.html">Command-line Tools</a>
+ <a title="Binary Releases" href="../www/binary-releases.html">Binary Releases</a>
</div>
<div class="sub">
- <a href="../www/command-line-processing.html">Processing</a>
+ <a title="Binary Release: Unix" href="../www/binary-releases.html#unix">Unix</a>
</div>
<div class="sub">
- <a href="../www/command-line-options.html">Options</a>
+ <a title="Binary Release: MacOS X" href="../www/binary-releases.html#macosx">Mac OS X</a>
</div>
<div class="sub">
- <a href="http://www.imagemagick.org/Usage/">Usage</a>
+ <a title="Binary Release: Windows" href="../www/binary-releases.html#windows">Windows</a>
</div>
+<div class="sep"></div>\r
<div class="menu">
- <a href="../www/api.html">Program Interfaces</a>
-</div>
-<div class="sub">
- <a href="../www/magick-wand.html">MagickWand</a>
+ <a title="Command-line Tools" href="../www/command-line-tools.html">Command-line Tools</a>
</div>
<div class="sub">
- <a href="../www/magick-core.html">MagickCore</a>
+ <a title="Command-line Tools: Processing" href="../www/command-line-processing.html">Processing</a>
</div>
<div class="sub">
- <a href="../www/perl-magick.html">PerlMagick</a>
+ <a title="Command-line Tools: Options" href="../www/command-line-options.html">Options</a>
</div>
<div class="sub">
- <a href="../Magick++/">Magick++</a>
+ <a title="Command-line Tools: Usage" href="http://www.imagemagick.org/Usage/">Usage</a>
</div>
<div class="menu">
- <a href="../www/architecture.html">Architecture</a>
+ <a title="Program Interfaces" href="../www/api.html">Program Interfaces</a>
</div>
-<div class="sep"></div>\r
-<div class="menu">
- <a href="../www/install-source.html">Install from Source</a>
+<div class="sub">
+ <a title="Program Interface: MagickWand" href="../www/magick-wand.html">MagickWand</a>
</div>
<div class="sub">
- <a href="../www/install-source.html#unix">Unix</a>
+ <a title="Program Interface: MagickCore" href="../www/magick-core.html">MagickCore</a>
</div>
<div class="sub">
- <a href="../www/install-source.html#windows">Windows</a>
- </div>
-<div class="menu">
- <a href="../www/binary-releases.html">Binary Releases</a>
+ <a title="Program Interface: PerlMagick" href="../www/perl-magick.html">PerlMagick</a>
</div>
<div class="sub">
- <a href="../www/binary-releases.html#unix">Unix</a>
+ <a title="Program Interface: Magick++" href="../Magick++/">Magick++</a>
+</div>
+<div class="sep"></div>\r
+<div class="menu">
+ <a title="Install from Source" href="../www/install-source.html">Install from Source</a>
</div>
<div class="sub">
- <a href="../www/binary-releases.html#macosx">Mac OS X</a>
+ <a title="Install from Source: Unix" href="../www/install-source.html#unix">Unix</a>
</div>
<div class="sub">
- <a href="../www/binary-releases.html#windows">Windows</a>
+ <a title="Install from Source: Windows" href="../www/install-source.html#windows">Windows</a>
+ </div>
+<div class="menu">
+ <a title="Resources" href="../www/resources.html">Resources</a>
</div>
<div class="menu">
- <a href="../www/resources.html">Resources</a>
+ <a title="Architecture" href="../www/architecture.html">Architecture</a>
</div>
-<div class="sep"></div>\r
<div class="menu">
- <a href="../www/download.html">Download</a>
+ <a title="Download" href="../www/download.html">Download</a>
</div>
<div class="sep"></div>\r
<div class="menu">
- <a href="http://www.imagemagick.org/script/search.php">Search</a>
+ <a title="Search" href="http://www.imagemagick.org/script/search.php">Search</a>
</div>
<div class="sep"></div>\r
<div class="menu">
- <a href="../www/sitemap.html">Site Map</a>
+ <a title="Site Map"href="../www/sitemap.html">Site Map</a>
</div>
<div class="sub">
- <a href="../www/links.html">Links</a>
+ <a title="Site Map: Links"href="../www/links.html">Links</a>
</div>
<div class="sep"></div>\r
<div class="menu">
- <a href="../www/sponsors.html">Sponsors:</a>
+ <a title="Sponsors" href="../www/sponsors.html">Sponsors:</a>
<div class="sponsbox">
<div class="sponsor">
- <a href="http://www.renehornig.com/" title="Webdesign">Webdesign</a><!-- 20110101000120 -->
+ <a title="Sponsor: Webdesign" href="http://www.renehornig.com/">Webdesign</a><!-- 20111001000240 -->
</div>
<div class="sponsor">
- <a href="http://www.deko.net">Deko.net</a><!-- 201101010600 Peterssen-->
+ <a title="Sponsor: Druckerei" href="http://print24.com/de/">Druckerei</a><!-- 201110010720 -->
</div>
<div class="sponsor">
- <a href="http://www.tomsgutscheine.de">Tom's Gutscheine</a><!-- 201005010360 invendio.de-->
+ <a title="Sponsor: Image Converter" href="http://www.batchphoto.com">Image Converter</a><!-- 201103010900 Bits Coffee-->
</div>
<div class="sponsor">
- <a href="http://www.online-kredit-index.de">Kredit</a><!-- 201007010120 Buchhorn -->
+ <a title="Sponsor: Flyer drucken" href="http://www.online-druck.biz">Flyer drucken</a><!-- 201109010900 Floeter-->
</div>
<div class="sponsor">
- <a href="http://www.blumenversender.com">Blumenversand</a><!-- 201005010120 -->
+ <a title="Sponsor: Webdesign Agentur" href="http://www.ventzke-partner.de">Webdesign Agentur</a><!-- 201101010480 invendio.de-->
</div>
<div class="sponsor">
- <a href="http://www.print24.de/">Druckerei</a><!-- 201009010720 -->
+ <a title="Sponsor: LVM Versicherung" href="http://www.neu-reich.de">LVM Versicherung</a><!-- 201101010480 -->
</div>
<div class="sponsor">
- <a href="http://www.allesdruck.de">Druckerei Online</a><!-- 201012011200 allesdruck.de-->
+ <a title="Sponsor: Diamonds are a Girls Best Friend" href="http://www.schmuck.org">Diamonds are a Girls Best Friend</a><!-- 201101010600 Peterssen-->
</div>
+<div class="sponsor">
+ <a title="Sponsor: Druckerei Online" href="http://www.allesdruck.de">Druckerei Online</a><!-- 201012011200 allesdruck.de-->
</div>
</div>
+</div>
+</div>\r
\r
-\r
+<div class="eastbar">\r
+ <script type="text/javascript">\r
+ <!--\r
+ google_ad_client = "pub-3129977114552745";\r
+ google_ad_slot = "0574824969";\r
+ google_ad_width = 160;\r
+ google_ad_height = 600;\r
+ //-->\r
+ </script>\r
+ <script type="text/javascript"\r
+ src="http://pagead2.googlesyndication.com/pagead/show_ads.js">\r
+ </script>\r
</div>\r
\r
<div class="main">\r
<h2><a name="intro"></a>Introduction to Enciphering and Deciphering Images</h2>
<div class="doc-section">
-<p>Most images, by design, are made to be viewed often and by many people. Web images, for example, may be viewed hundreds of times a day by a multitude of web vistors. However, in some cases, you may want to keep a particular image private so that only you or perhaps a select group of your friends or web visitors can view it. ImageMagick permits you to scramble your images such that unless someone knows your secret key, they will be unable to view the original content.</p>
+<p>Most images, by design, are made to be viewed often and by many people. Web images, for example, may be viewed hundreds of times a day by a multitude of web vistors. However, in some cases, you may want to keep a particular image private so that only you or perhaps a select group of your friends or web visitors can view it. ImageMagick permits you to scramble your images such that unless someone knows your passphrase, they will be unable to view the original content.</p>
<p>You could use an <a href="http://www.wizards-toolkit.org/www/encipher.html">enciphering</a> utility to scramble your image but they typically scramble the entire file making it unrecognizable as an image format. With ImageMagick, only the pixels are scrambled. The scrambled image continues to be recognized as an image and will even display in your web page. However, the content appears as gibberish, nothing like the original content.</p>
<h2><a name="encipher"></a>Encipher an Image</h2>
<div class="doc-section">
-<p>Use the <a href="../www/command-line-options.html#encipher">-encipher</a> option to scramble your image so that it is unrecognizable. The option requires a filename that contains your secret key. In this example we scramble an image and save it in the PNG format:</p>
+<p>Use the <a href="../www/command-line-options.html#encipher">-encipher</a> option to scramble your image so that it is unrecognizable. The option requires a filename that contains your passphrase. In this example we scramble an image and save it in the PNG format:</p>
-<p class='crt'><span class="crtprompt"> $magick> </span><span class='crtin'>convert rose.jpg -encipher passkey.txt rose.png</span></p>
-<p>Here we encipher an image using another image as the passkey:</p>
+<p class='crt'><span class="crtprompt"> $magick> </span><span class='crtin'>convert rose.jpg -encipher passphrase.txt rose.png</span></p>
+<p>Here we encipher an image using another image as the passphrase:</p>
<p class='crt'><span class="crtprompt"> $magick> </span><span class='crtin'>convert rose.jpg -encipher smiley.gif rose.png</span></p>
</div>
<h2><a name="decipher"></a>Decipher an Image</h2>
<div class="doc-section">
-<p>Use the <a href="../www/command-line-options.html#decipher">-decipher</a> option to unscramble your image so that it is recognizable once again. The option requires a filename that contains your secret key. In this example we unscramble an image and save it in the JPEG format:</p>
+<p>Use the <a href="../www/command-line-options.html#decipher">-decipher</a> option to unscramble your image so that it is recognizable once again. The option requires a filename that contains your passphrase. In this example we unscramble an image and save it in the JPEG format:</p>
-<p class='crt'><span class="crtprompt"> $magick> </span><span class='crtin'>convert rose.png -decipher passkey.txt rose.jpg</span></p>
+<p class='crt'><span class="crtprompt"> $magick> </span><span class='crtin'>convert rose.png -decipher passphrase.txt rose.jpg</span></p>
</div>
<h2><a name="caveats"></a>Encipher and Decipher Caveats</h2>
<div class="doc-section">
-<p>Some formats do not support enciphered pixels-- the JPEG or GIF format, for example. To ensure your image format is supported, encipher a test image and verify you can restore its original content <em>before</em> you encipher any additional images in that format.</p>
+<p>Some formats do not support enciphered pixels-- the JPEG or GIF format, for
+example. To ensure your image format is supported, encipher a test image and
+verify you can restore its original content <em>before</em> you encipher any
+additional images in that format.</p>
-<p>The passkey can be any combinations of letters and symbols. It should be a minimum of 12 character combinations to ensure your image remains private. Also make sure your passkey file permissions prevent others from reading it otherwise unintended users may be able to view the original image content.</p>
+<p>The image format also should be 8-bit and RGB (TrueColor). As such you may
+like to include the options "-depth 8 -type TrueColor" before the output
+filename. </p>
-<p>You can only restore the original image content if you know your passkey. If you lose or forget it, your original image content is lost forever.</p>
+<p>The passphrase can be any combinations of letters and symbols. It should
+be a minimum of 12 character combinations to help ensure your image remains
+private. Also make sure your passphrase file permissions prevent others from
+reading it otherwise unintended users may be able to view the original image
+content.</p>
-<p>ImageMagick only scrambles the image pixels. The image metadata remains untouched and readable by anyone with access to the image file.</p>
+<p>You can only restore the original image content if you know your
+passphrase. If you lose or forget it, your original image content is lost
+forever.</p>
-<p>ImageMagick uses the <a href="http://en.wikipedia.org/wiki/Advanced_Encryption_Standard">AES</a> cipher in cipher feedback mode. We use the passkey to derive the cipher key and the required nonce.</p>
+<p>ImageMagick only scrambles the image pixels. The image metadata remains
+untouched and readable by anyone with access to the image file.</p>
-<p>Currently only ImageMagick can restore your enciphered image content. We use a standard cipher and mode so other vendors are encouraged to support enciphered image content.</p>
+<p>ImageMagick uses the <a
+href="http://en.wikipedia.org/wiki/Advanced_Encryption_Standard">AES</a>
+cipher in cipher feedback mode. We use the passphrase to derive the cipher
+key and the required nonce.</p>
-</div>\r
+<p>Currently only ImageMagick can restore your enciphered image content. We
+use a standard cipher and mode so other vendors are encouraged to support
+enciphered image content.</p>
+
+<p>Some small practical examples of image enciphering can be found in IM
+Examples <A HREF="http://www.imagemagick.org/Usage/transform/#encipher"
+>Encrypting Image Data</A>. </p>
+
+</div>
+\r
</div>\r
\r
<div id="linkbar">\r
- <!-- <span id="linkbar-west"> </span> -->\r
+ <span id="linkbar-west"> </span>\r
<span id="linkbar-center">\r
<a href="http://www.imagemagick.org/discourse-server/">Discourse Server</a> •\r
- <a href="http://www.imagemagick.org/MagickStudio/scripts/MagickStudio.cgi">Studio</a>\r
+
<a href="http://www.imagemagick.org/MagickStudio/scripts/MagickStudio.cgi">Studio</a>
\r </span>\r
<span id="linkbar-east"> </span>\r
</div>\r
<span id="footer-east"> <a href="http://www.imagemagick.org/script/contact.php">Contact the Wizards</a></span>\r
</div>\r
<div style="clear: both; margin: 0; width: 100%; "></div>\r
+ <script type="text/javascript">\r
+ var _gaq = _gaq || [];\r
+ _gaq.push(['_setAccount', 'UA-17690367-1']);\r
+ _gaq.push(['_trackPageview']);\r
+\r
+ (function() {\r
+ var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;\r
+ ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';\r
+ var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);\r
+ })();\r
+ </script>\r
</body>\r
</html>\r
projects / imagemagick / blobdiff