diff options
Diffstat (limited to 'doc/html/qimageio.html')
| -rw-r--r-- | doc/html/qimageio.html | 372 |
1 files changed, 372 insertions, 0 deletions
diff --git a/doc/html/qimageio.html b/doc/html/qimageio.html new file mode 100644 index 000000000..52e2ad685 --- /dev/null +++ b/doc/html/qimageio.html @@ -0,0 +1,372 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/kernel/qimage.cpp:3715 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>TQImageIO Class</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>TQImageIO Class Reference</h1> + +<p>The TQImageIO class contains parameters for loading and +saving images. +<a href="#details">More...</a> +<p><tt>#include <<a href="qimage-h.html">qimage.h</a>></tt> +<p><a href="qimageio-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#TQImageIO"><b>TQImageIO</b></a> ()</li> +<li class=fn><a href="#TQImageIO-2"><b>TQImageIO</b></a> ( TQIODevice * ioDevice, const char * format )</li> +<li class=fn><a href="#TQImageIO-3"><b>TQImageIO</b></a> ( const TQString & fileName, const char * format )</li> +<li class=fn><a href="#~TQImageIO"><b>~TQImageIO</b></a> ()</li> +<li class=fn>const TQImage & <a href="#image"><b>image</b></a> () const</li> +<li class=fn>int <a href="#status"><b>status</b></a> () const</li> +<li class=fn>const char * <a href="#format"><b>format</b></a> () const</li> +<li class=fn>TQIODevice * <a href="#ioDevice"><b>ioDevice</b></a> () const</li> +<li class=fn>TQString <a href="#fileName"><b>fileName</b></a> () const</li> +<li class=fn>int <a href="#quality"><b>quality</b></a> () const</li> +<li class=fn>TQString <a href="#description"><b>description</b></a> () const</li> +<li class=fn>const char * <a href="#parameters"><b>parameters</b></a> () const</li> +<li class=fn>float <a href="#gamma"><b>gamma</b></a> () const</li> +<li class=fn>void <a href="#setImage"><b>setImage</b></a> ( const TQImage & image )</li> +<li class=fn>void <a href="#setStatus"><b>setStatus</b></a> ( int status )</li> +<li class=fn>void <a href="#setFormat"><b>setFormat</b></a> ( const char * format )</li> +<li class=fn>void <a href="#setIODevice"><b>setIODevice</b></a> ( TQIODevice * ioDevice )</li> +<li class=fn>void <a href="#setFileName"><b>setFileName</b></a> ( const TQString & fileName )</li> +<li class=fn>void <a href="#setQuality"><b>setQuality</b></a> ( int q )</li> +<li class=fn>void <a href="#setDescription"><b>setDescription</b></a> ( const TQString & description )</li> +<li class=fn>void <a href="#setParameters"><b>setParameters</b></a> ( const char * parameters )</li> +<li class=fn>void <a href="#setGamma"><b>setGamma</b></a> ( float gamma )</li> +<li class=fn>bool <a href="#read"><b>read</b></a> ()</li> +<li class=fn>bool <a href="#write"><b>write</b></a> ()</li> +</ul> +<h2>Static Public Members</h2> +<ul> +<li class=fn>const char * <a href="#imageFormat"><b>imageFormat</b></a> ( const TQString & fileName )</li> +<li class=fn>const char * <a href="#imageFormat-2"><b>imageFormat</b></a> ( TQIODevice * d )</li> +<li class=fn>TQStrList <a href="#inputFormats"><b>inputFormats</b></a> ()</li> +<li class=fn>TQStrList <a href="#outputFormats"><b>outputFormats</b></a> ()</li> +<li class=fn>void <a href="#defineIOHandler"><b>defineIOHandler</b></a> ( const char * format, const char * header, const char * flags, image_io_handler readImage, image_io_handler writeImage )</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +<p> The TQImageIO class contains parameters for loading and +saving images. +<p> + + +<p> TQImageIO contains a <a href="qiodevice.html">TQIODevice</a> object that is used for image data +I/O. The programmer can install new image file formats in addition +to those that TQt provides. +<p> TQt currently supports the following image file formats: PNG, BMP, +XBM, XPM and PNM. It may also support JPEG, MNG and GIF, if +specially configured during compilation. The different PNM formats +are: PBM (P1 or P4), PGM (P2 or P5), and PPM (P3 or P6). +<p> You don't normally need to use this class; <a href="qpixmap.html#load">TQPixmap::load</a>(), +<a href="qpixmap.html#save">TQPixmap::save</a>(), and <a href="qimage.html">TQImage</a> contain sufficient functionality. +<p> For image files that contain sequences of images, only the first +is read. See <a href="qmovie.html">TQMovie</a> for loading multiple images. +<p> PBM, PGM, and PPM format <em>output</em> is always in the more condensed +raw format. PPM and PGM files with more than 256 levels of +intensity are scaled down when reading. +<p> <b>Warning:</b> If you are in a country which recognizes software patents +and in which Unisys holds a patent on LZW compression and/or +decompression and you want to use GIF, Unisys may retquire you to +license the technology. Such countries include Canada, Japan, the +USA, France, Germany, Italy and the UK. +<p> GIF support may be removed completely in a future version of TQt. +We recommend using the PNG format. +<p> <p>See also <a href="qimage.html">TQImage</a>, <a href="qpixmap.html">TQPixmap</a>, <a href="qfile.html">TQFile</a>, <a href="qmovie.html">TQMovie</a>, <a href="graphics.html">Graphics Classes</a>, <a href="images.html">Image Processing Classes</a>, and <a href="io.html">Input/Output and Networking</a>. + +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="TQImageIO"></a>TQImageIO::TQImageIO () +</h3> +Constructs a TQImageIO object with all parameters set to zero. + +<h3 class=fn><a name="TQImageIO-2"></a>TQImageIO::TQImageIO ( <a href="qiodevice.html">TQIODevice</a> * ioDevice, const char * format ) +</h3> +Constructs a TQImageIO object with the I/O device <em>ioDevice</em> and a +<em>format</em> tag. + +<h3 class=fn><a name="TQImageIO-3"></a>TQImageIO::TQImageIO ( const <a href="qstring.html">TQString</a> & fileName, const char * format ) +</h3> +Constructs a TQImageIO object with the file name <em>fileName</em> and a +<em>format</em> tag. + +<h3 class=fn><a name="~TQImageIO"></a>TQImageIO::~TQImageIO () +</h3> +Destroys the object and all related data. + +<h3 class=fn>void <a name="defineIOHandler"></a>TQImageIO::defineIOHandler ( const char * format, const char * header, const char * flags, image_io_handler readImage, image_io_handler writeImage )<tt> [static]</tt> +</h3> +Defines an image I/O handler for the image format called <em>format</em>, which is recognized using the <a href="qregexp.html#details">regular expression</a> <em>header</em>, read using <em>readImage</em> and +written using <em>writeImage</em>. +<p> <em>flags</em> is a string of single-character flags for this format. +The only flag defined currently is T (upper case), so the only +legal value for <em>flags</em> are "T" and the empty string. The "T" +flag means that the image file is a text file, and TQt should treat +all newline conventions as equivalent. (XPM files and some PPM +files are text files for example.) +<p> <em>format</em> is used to select a handler to write a <a href="qimage.html">TQImage</a>; <em>header</em> +is used to select a handler to read an image file. +<p> If <em>readImage</em> is a null pointer, the TQImageIO will not be able +to read images in <em>format</em>. If <em>writeImage</em> is a null pointer, +the TQImageIO will not be able to write images in <em>format</em>. If +both are null, the TQImageIO object is valid but useless. +<p> Example: +<pre> + void readGIF( TQImageIO *image ) + { + // read the image using the image-><a href="#ioDevice">ioDevice</a>() + } + + void writeGIF( TQImageIO *image ) + { + // write the image using the image-><a href="#ioDevice">ioDevice</a>() + } + + // add the GIF image handler + + TQImageIO::<a href="#defineIOHandler">defineIOHandler</a>( "GIF", + "^GIF[0-9][0-9][a-z]", + 0, + readGIF, + writeGIF ); + </pre> + +<p> Before the regex test, all the 0 bytes in the file header are +converted to 1 bytes. This is done because when TQt was +ASCII-based, <a href="qregexp.html">TQRegExp</a> could not handle 0 bytes in strings. +<p> The regexp is only applied on the first 14 bytes of the file. +<p> Note that TQt assumes that there is only one handler per format; if +two handlers support the same format, TQt will choose one +arbitrarily. It is not possible to have one handler support +reading, and another support writing. + +<h3 class=fn><a href="qstring.html">TQString</a> <a name="description"></a>TQImageIO::description () const +</h3> + +<p> Returns the image description string. +<p> <p>See also <a href="#setDescription">setDescription</a>(). + +<h3 class=fn><a href="qstring.html">TQString</a> <a name="fileName"></a>TQImageIO::fileName () const +</h3> + +<p> Returns the file name currently set. +<p> <p>See also <a href="#setFileName">setFileName</a>(). + +<h3 class=fn>const char * <a name="format"></a>TQImageIO::format () const +</h3> + +<p> Returns the image format string or 0 if no format has been +explicitly set. + +<h3 class=fn>float <a name="gamma"></a>TQImageIO::gamma () const +</h3> +Returns the gamma value at which the image will be viewed. +<p> <p>See also <a href="#setGamma">setGamma</a>(). + +<h3 class=fn>const <a href="qimage.html">TQImage</a> & <a name="image"></a>TQImageIO::image () const +</h3> + +<p> Returns the image currently set. +<p> <p>See also <a href="#setImage">setImage</a>(). + +<h3 class=fn>const char * <a name="imageFormat"></a>TQImageIO::imageFormat ( const <a href="qstring.html">TQString</a> & fileName )<tt> [static]</tt> +</h3> +Returns a string that specifies the image format of the file <em>fileName</em>, or null if the file cannot be read or if the format is +not recognized. + +<h3 class=fn>const char * <a name="imageFormat-2"></a>TQImageIO::imageFormat ( <a href="qiodevice.html">TQIODevice</a> * d )<tt> [static]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns a string that specifies the image format of the image read +from IO device <em>d</em>, or 0 if the device cannot be read or if the +format is not recognized. +<p> Make sure that <em>d</em> is at the right position in the device (for +example, at the beginning of the file). +<p> <p>See also <a href="qiodevice.html#at">TQIODevice::at</a>(). + +<h3 class=fn><a href="qstrlist.html">TQStrList</a> <a name="inputFormats"></a>TQImageIO::inputFormats ()<tt> [static]</tt> +</h3> +Returns a sorted list of image formats that are supported for +image input. + +<h3 class=fn><a href="qiodevice.html">TQIODevice</a> * <a name="ioDevice"></a>TQImageIO::ioDevice () const +</h3> + +<p> Returns the IO device currently set. +<p> <p>See also <a href="#setIODevice">setIODevice</a>(). + +<h3 class=fn><a href="qstrlist.html">TQStrList</a> <a name="outputFormats"></a>TQImageIO::outputFormats ()<tt> [static]</tt> +</h3> +Returns a sorted list of image formats that are supported for +image output. + +<p>Example: <a href="scribble-example.html#x911">scribble/scribble.cpp</a>. +<h3 class=fn>const char * <a name="parameters"></a>TQImageIO::parameters () const +</h3> +Returns the image's parameters string. +<p> <p>See also <a href="#setParameters">setParameters</a>(). + +<h3 class=fn>int <a name="quality"></a>TQImageIO::quality () const +</h3> +Returns the quality of the written image, related to the +compression ratio. +<p> <p>See also <a href="#setQuality">setQuality</a>() and <a href="qimage.html#save">TQImage::save</a>(). + +<h3 class=fn>bool <a name="read"></a>TQImageIO::read () +</h3> +Reads an image into memory and returns TRUE if the image was +successfully read; otherwise returns FALSE. +<p> Before reading an image you must set an IO device or a file name. +If both an IO device and a file name have been set, the IO device +will be used. +<p> Setting the image file format string is optional. +<p> Note that this function does <em>not</em> set the <a href="#format">format</a> used to read the image. If you need that +information, use the <a href="#imageFormat">imageFormat</a>() static functions. +<p> Example: +<p> <pre> + TQImageIO iio; + <a href="qpixmap.html">TQPixmap</a> pixmap; + iio.<a href="#setFileName">setFileName</a>( "vegeburger.bmp" ); + if ( image.read() ) // ok + pixmap = iio.<a href="#image">image</a>(); // convert to pixmap + </pre> + +<p> <p>See also <a href="#setIODevice">setIODevice</a>(), <a href="#setFileName">setFileName</a>(), <a href="#setFormat">setFormat</a>(), <a href="#write">write</a>(), and <a href="qpixmap.html#load">TQPixmap::load</a>(). + +<h3 class=fn>void <a name="setDescription"></a>TQImageIO::setDescription ( const <a href="qstring.html">TQString</a> & description ) +</h3> +Sets the image description string for image handlers that support +image descriptions to <em>description</em>. +<p> Currently, no image format supported by TQt uses the description +string. + +<h3 class=fn>void <a name="setFileName"></a>TQImageIO::setFileName ( const <a href="qstring.html">TQString</a> & fileName ) +</h3> +Sets the name of the file to read or write an image from to <em>fileName</em>. +<p> <p>See also <a href="#setIODevice">setIODevice</a>(). + +<h3 class=fn>void <a name="setFormat"></a>TQImageIO::setFormat ( const char * format ) +</h3> +Sets the image format to <em>format</em> for the image to be read or +written. +<p> It is necessary to specify a format before writing an image, but +it is not necessary to specify a format before reading an image. +<p> If no format has been set, TQt guesses the image format before +reading it. If a format is set the image will only be read if it +has that format. +<p> <p>See also <a href="#read">read</a>(), <a href="#write">write</a>(), and <a href="#format">format</a>(). + +<h3 class=fn>void <a name="setGamma"></a>TQImageIO::setGamma ( float gamma ) +</h3> +Sets the gamma value at which the image will be viewed to <em>gamma</em>. If the image format stores a gamma value for which the +image is intended to be used, then this setting will be used to +modify the image. Setting to 0.0 will disable gamma correction +(i.e. any specification in the file will be ignored). +<p> The default value is 0.0. +<p> <p>See also <a href="#gamma">gamma</a>(). + +<h3 class=fn>void <a name="setIODevice"></a>TQImageIO::setIODevice ( <a href="qiodevice.html">TQIODevice</a> * ioDevice ) +</h3> +Sets the IO device to be used for reading or writing an image. +<p> Setting the IO device allows images to be read/written to any +block-oriented <a href="qiodevice.html">TQIODevice</a>. +<p> If <em>ioDevice</em> is not null, this IO device will override file name +settings. +<p> <p>See also <a href="#setFileName">setFileName</a>(). + +<h3 class=fn>void <a name="setImage"></a>TQImageIO::setImage ( const <a href="qimage.html">TQImage</a> & image ) +</h3> +Sets the image to <em>image</em>. +<p> <p>See also <a href="#image">image</a>(). + +<h3 class=fn>void <a name="setParameters"></a>TQImageIO::setParameters ( const char * parameters ) +</h3> +Sets the image's parameter string to <em>parameters</em>. This is for +image handlers that retquire special parameters. +<p> Although the current image formats supported by TQt ignore the +parameters string, it may be used in future extensions or by +contributions (for example, JPEG). +<p> <p>See also <a href="#parameters">parameters</a>(). + +<h3 class=fn>void <a name="setQuality"></a>TQImageIO::setQuality ( int q ) +</h3> +Sets the quality of the written image to <em>q</em>, related to the +compression ratio. +<p> <em>q</em> must be in the range -1..100. Specify 0 to obtain small +compressed files, 100 for large uncompressed files. (-1 signifies +the default compression.) +<p> <p>See also <a href="#quality">quality</a>() and <a href="qimage.html#save">TQImage::save</a>(). + +<h3 class=fn>void <a name="setStatus"></a>TQImageIO::setStatus ( int status ) +</h3> +Sets the image IO status to <em>status</em>. A non-zero value indicates +an error, whereas 0 means that the IO operation was successful. +<p> <p>See also <a href="#status">status</a>(). + +<h3 class=fn>int <a name="status"></a>TQImageIO::status () const +</h3> + +<p> Returns the image's IO status. A non-zero value indicates an +error, whereas 0 means that the IO operation was successful. +<p> <p>See also <a href="#setStatus">setStatus</a>(). + +<h3 class=fn>bool <a name="write"></a>TQImageIO::write () +</h3> +Writes an image to an IO device and returns TRUE if the image was +successfully written; otherwise returns FALSE. +<p> Before writing an image you must set an IO device or a file name. +If both an IO device and a file name have been set, the IO device +will be used. +<p> The image will be written using the specified image format. +<p> Example: +<pre> + TQImageIO iio; + <a href="qimage.html">TQImage</a> im; + im = pixmap; // convert to image + iio.<a href="#setImage">setImage</a>( im ); + iio.<a href="#setFileName">setFileName</a>( "vegeburger.bmp" ); + iio.<a href="#setFormat">setFormat</a>( "BMP" ); + if ( iio.<a href="#write">write</a>() ) + // returned TRUE if written successfully + </pre> + +<p> <p>See also <a href="#setIODevice">setIODevice</a>(), <a href="#setFileName">setFileName</a>(), <a href="#setFormat">setFormat</a>(), <a href="#read">read</a>(), and <a href="qpixmap.html#save">TQPixmap::save</a>(). + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">TQt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center> +<table width=100% cellspacing=0 border=0><tr> +<td>Copyright © 2007 +<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> +<td align=right><div align=right>TQt 3.3.8</div> +</table></div></address></body> +</html> |