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diff --git a/doc/html/qimage.html b/doc/html/qimage.html new file mode 100644 index 0000000..e2b88fd --- /dev/null +++ b/doc/html/qimage.html @@ -0,0 +1,1117 @@ +<!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:69 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QImage 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>QImage Class Reference</h1> + +<p>The QImage class provides a hardware-independent pixmap +representation with direct access to the pixel data. +<a href="#details">More...</a> +<p><tt>#include <<a href="qimage-h.html">qimage.h</a>></tt> +<p><a href="qimage-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn>enum <a href="#Endian-enum"><b>Endian</b></a> { IgnoreEndian, BigEndian, LittleEndian }</li> +<li class=fn><a href="#QImage"><b>QImage</b></a> ()</li> +<li class=fn><a href="#QImage-2"><b>QImage</b></a> ( int w, int h, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian )</li> +<li class=fn><a href="#QImage-3"><b>QImage</b></a> ( const QSize & size, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian )</li> +<li class=fn><a href="#QImage-4"><b>QImage</b></a> ( const QString & fileName, const char * format = 0 )</li> +<li class=fn><a href="#QImage-5"><b>QImage</b></a> ( const char * const xpm[] )</li> +<li class=fn><a href="#QImage-6"><b>QImage</b></a> ( const QByteArray & array )</li> +<li class=fn><a href="#QImage-7"><b>QImage</b></a> ( uchar * yourdata, int w, int h, int depth, QRgb * colortable, int numColors, Endian bitOrder )</li> +<li class=fn><a href="#QImage-8"><b>QImage</b></a> ( uchar * yourdata, int w, int h, int depth, int bpl, QRgb * colortable, int numColors, Endian bitOrder )</li> +<li class=fn><a href="#QImage-9"><b>QImage</b></a> ( const QImage & image )</li> +<li class=fn><a href="#~QImage"><b>~QImage</b></a> ()</li> +<li class=fn>QImage & <a href="#operator-eq"><b>operator=</b></a> ( const QImage & image )</li> +<li class=fn>QImage & <a href="#operator-eq-2"><b>operator=</b></a> ( const QPixmap & pixmap )</li> +<li class=fn>bool <a href="#operator-eq-eq"><b>operator==</b></a> ( const QImage & i ) const</li> +<li class=fn>bool <a href="#operator!-eq"><b>operator!=</b></a> ( const QImage & i ) const</li> +<li class=fn>void <a href="#detach"><b>detach</b></a> ()</li> +<li class=fn>QImage <a href="#copy"><b>copy</b></a> () const</li> +<li class=fn>QImage <a href="#copy-2"><b>copy</b></a> ( int x, int y, int w, int h, int conversion_flags = 0 ) const</li> +<li class=fn>QImage <a href="#copy-3"><b>copy</b></a> ( const QRect & r ) const</li> +<li class=fn>bool <a href="#isNull"><b>isNull</b></a> () const</li> +<li class=fn>int <a href="#width"><b>width</b></a> () const</li> +<li class=fn>int <a href="#height"><b>height</b></a> () const</li> +<li class=fn>QSize <a href="#size"><b>size</b></a> () const</li> +<li class=fn>QRect <a href="#rect"><b>rect</b></a> () const</li> +<li class=fn>int <a href="#depth"><b>depth</b></a> () const</li> +<li class=fn>int <a href="#numColors"><b>numColors</b></a> () const</li> +<li class=fn>Endian <a href="#bitOrder"><b>bitOrder</b></a> () const</li> +<li class=fn>QRgb <a href="#color"><b>color</b></a> ( int i ) const</li> +<li class=fn>void <a href="#setColor"><b>setColor</b></a> ( int i, QRgb c )</li> +<li class=fn>void <a href="#setNumColors"><b>setNumColors</b></a> ( int numColors )</li> +<li class=fn>bool <a href="#hasAlphaBuffer"><b>hasAlphaBuffer</b></a> () const</li> +<li class=fn>void <a href="#setAlphaBuffer"><b>setAlphaBuffer</b></a> ( bool enable )</li> +<li class=fn>bool <a href="#allGray"><b>allGray</b></a> () const</li> +<li class=fn>bool <a href="#isGrayscale"><b>isGrayscale</b></a> () const</li> +<li class=fn>uchar * <a href="#bits"><b>bits</b></a> () const</li> +<li class=fn>uchar * <a href="#scanLine"><b>scanLine</b></a> ( int i ) const</li> +<li class=fn>uchar ** <a href="#jumpTable"><b>jumpTable</b></a> () const</li> +<li class=fn>QRgb * <a href="#colorTable"><b>colorTable</b></a> () const</li> +<li class=fn>int <a href="#numBytes"><b>numBytes</b></a> () const</li> +<li class=fn>int <a href="#bytesPerLine"><b>bytesPerLine</b></a> () const</li> +<li class=fn>bool <a href="#create"><b>create</b></a> ( int width, int height, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian )</li> +<li class=fn>bool <a href="#create-2"><b>create</b></a> ( const QSize &, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian )</li> +<li class=fn>void <a href="#reset"><b>reset</b></a> ()</li> +<li class=fn>void <a href="#fill"><b>fill</b></a> ( uint pixel )</li> +<li class=fn>void <a href="#invertPixels"><b>invertPixels</b></a> ( bool invertAlpha = TRUE )</li> +<li class=fn>QImage <a href="#convertDepth-2"><b>convertDepth</b></a> ( int depth ) const</li> +<li class=fn>QImage <a href="#convertDepthWithPalette"><b>convertDepthWithPalette</b></a> ( int d, QRgb * palette, int palette_count, int conversion_flags = 0 ) const</li> +<li class=fn>QImage <a href="#convertDepth"><b>convertDepth</b></a> ( int depth, int conversion_flags ) const</li> +<li class=fn>QImage <a href="#convertBitOrder"><b>convertBitOrder</b></a> ( Endian bitOrder ) const</li> +<li class=fn>enum <a href="#ScaleMode-enum"><b>ScaleMode</b></a> { ScaleFree, ScaleMin, ScaleMax }</li> +<li class=fn>QImage <a href="#smoothScale"><b>smoothScale</b></a> ( int w, int h, ScaleMode mode = ScaleFree ) const</li> +<li class=fn>QImage <a href="#smoothScale-2"><b>smoothScale</b></a> ( const QSize & s, ScaleMode mode = ScaleFree ) const</li> +<li class=fn>QImage <a href="#scale"><b>scale</b></a> ( int w, int h, ScaleMode mode = ScaleFree ) const</li> +<li class=fn>QImage <a href="#scale-2"><b>scale</b></a> ( const QSize & s, ScaleMode mode = ScaleFree ) const</li> +<li class=fn>QImage <a href="#scaleWidth"><b>scaleWidth</b></a> ( int w ) const</li> +<li class=fn>QImage <a href="#scaleHeight"><b>scaleHeight</b></a> ( int h ) const</li> +<li class=fn>QImage <a href="#xForm"><b>xForm</b></a> ( const QWMatrix & matrix ) const</li> +<li class=fn>QImage <a href="#createAlphaMask"><b>createAlphaMask</b></a> ( int conversion_flags = 0 ) const</li> +<li class=fn>QImage <a href="#createHeuristicMask"><b>createHeuristicMask</b></a> ( bool clipTight = TRUE ) const</li> +<li class=fn>QImage <a href="#mirror"><b>mirror</b></a> () const</li> +<li class=fn>QImage <a href="#mirror-2"><b>mirror</b></a> ( bool horizontal, bool vertical ) const</li> +<li class=fn>QImage <a href="#swapRGB"><b>swapRGB</b></a> () const</li> +<li class=fn>bool <a href="#load"><b>load</b></a> ( const QString & fileName, const char * format = 0 )</li> +<li class=fn>bool <a href="#loadFromData"><b>loadFromData</b></a> ( const uchar * buf, uint len, const char * format = 0 )</li> +<li class=fn>bool <a href="#loadFromData-2"><b>loadFromData</b></a> ( QByteArray buf, const char * format = 0 )</li> +<li class=fn>bool <a href="#save"><b>save</b></a> ( const QString & fileName, const char * format, int quality = -1 ) const</li> +<li class=fn>bool <a href="#save-2"><b>save</b></a> ( QIODevice * device, const char * format, int quality = -1 ) const</li> +<li class=fn>bool <a href="#valid"><b>valid</b></a> ( int x, int y ) const</li> +<li class=fn>int <a href="#pixelIndex"><b>pixelIndex</b></a> ( int x, int y ) const</li> +<li class=fn>QRgb <a href="#pixel"><b>pixel</b></a> ( int x, int y ) const</li> +<li class=fn>void <a href="#setPixel"><b>setPixel</b></a> ( int x, int y, uint index_or_rgb )</li> +<li class=fn>int <a href="#dotsPerMeterX"><b>dotsPerMeterX</b></a> () const</li> +<li class=fn>int <a href="#dotsPerMeterY"><b>dotsPerMeterY</b></a> () const</li> +<li class=fn>void <a href="#setDotsPerMeterX"><b>setDotsPerMeterX</b></a> ( int x )</li> +<li class=fn>void <a href="#setDotsPerMeterY"><b>setDotsPerMeterY</b></a> ( int y )</li> +<li class=fn>QPoint <a href="#offset"><b>offset</b></a> () const</li> +<li class=fn>void <a href="#setOffset"><b>setOffset</b></a> ( const QPoint & p )</li> +<li class=fn>QValueList<QImageTextKeyLang> <a href="#textList"><b>textList</b></a> () const</li> +<li class=fn>QStringList <a href="#textLanguages"><b>textLanguages</b></a> () const</li> +<li class=fn>QStringList <a href="#textKeys"><b>textKeys</b></a> () const</li> +<li class=fn>QString <a href="#text"><b>text</b></a> ( const char * key, const char * lang = 0 ) const</li> +<li class=fn>QString <a href="#text-2"><b>text</b></a> ( const QImageTextKeyLang & kl ) const</li> +<li class=fn>void <a href="#setText"><b>setText</b></a> ( const char * key, const char * lang, const QString & s )</li> +</ul> +<h2>Static Public Members</h2> +<ul> +<li class=fn>QImage <a href="#fromMimeSource"><b>fromMimeSource</b></a> ( const QString & abs_name )</li> +<li class=fn>Endian <a href="#systemBitOrder"><b>systemBitOrder</b></a> ()</li> +<li class=fn>Endian <a href="#systemByteOrder"><b>systemByteOrder</b></a> ()</li> +<li class=fn>const char * <a href="#imageFormat"><b>imageFormat</b></a> ( const QString & fileName )</li> +<li class=fn>QStrList <a href="#inputFormats"><b>inputFormats</b></a> ()</li> +<li class=fn>QStrList <a href="#outputFormats"><b>outputFormats</b></a> ()</li> +<li class=fn>QStringList <a href="#inputFormatList"><b>inputFormatList</b></a> ()</li> +<li class=fn>QStringList <a href="#outputFormatList"><b>outputFormatList</b></a> ()</li> +</ul> +<h2>Related Functions</h2> +<ul> +<li class=fn>QDataStream & <a href="#operator-lt-lt"><b>operator<<</b></a> ( QDataStream & s, const QImage & image )</li> +<li class=fn>QDataStream & <a href="#operator-gt-gt"><b>operator>></b></a> ( QDataStream & s, QImage & image )</li> +<li class=fn>void <a href="#bitBlt"><b>bitBlt</b></a> ( QImage * dst, int dx, int dy, const QImage * src, int sx, int sy, int sw, int sh, int conversion_flags )</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + +The QImage class provides a hardware-independent pixmap +representation with direct access to the pixel data. +<p> + + + +<p> It is one of the two classes Qt provides for dealing with images, +the other being <a href="qpixmap.html">QPixmap</a>. QImage is designed and optimized for I/O +and for direct pixel access/manipulation. QPixmap is designed and +optimized for drawing. There are (slow) functions to convert +between QImage and QPixmap: <a href="qpixmap.html#convertToImage">QPixmap::convertToImage</a>() and +<a href="qpixmap.html#convertFromImage">QPixmap::convertFromImage</a>(). +<p> An image has the parameters <a href="#width">width</a>, <a href="#height">height</a> and <a href="#depth">depth</a> (bits per +pixel, bpp), a color table and the actual <a href="#bits">pixels</a>. QImage supports 1-bpp, 8-bpp and 32-bpp image +data. 1-bpp and 8-bpp images use a color lookup table; the pixel +value is a color table index. +<p> 32-bpp images encode an RGB value in 24 bits and ignore the color +table. The most significant byte is used for the <a href="#setAlphaBuffer">alpha buffer</a>. +<p> An entry in the color table is an RGB triplet encoded as a <tt>uint</tt>. Use the <a href="qcolor.html#qRed">qRed()</a>, <a href="qcolor.html#qGreen">qGreen()</a> and <a href="qcolor.html#qBlue">qBlue()</a> functions (<a href="qcolor-h.html">qcolor.h</a>) to access the components, and <a href="qcolor.html#qRgb">qRgb</a> to make an RGB triplet (see the <a href="qcolor.html">QColor</a> class +documentation). +<p> 1-bpp (monochrome) images have a color table with a most two +colors. There are two different formats: big endian (MSB first) or +little endian (LSB first) bit order. To access a single bit you +will must do some bit shifts: +<p> <pre> + QImage image; + // sets bit at (x,y) to 1 + if ( image.<a href="#bitOrder">bitOrder</a>() == QImage::<a href="#Endian-enum">LittleEndian</a> ) + *(image.<a href="#scanLine">scanLine</a>(y) + (x >> 3)) |= 1 << (x & 7); + else + *(image.<a href="#scanLine">scanLine</a>(y) + (x >> 3)) |= 1 << (7 - (x & 7)); + </pre> + +<p> If this looks complicated, it might be a good idea to convert the +1-bpp image to an 8-bpp image using <a href="#convertDepth">convertDepth</a>(). +<p> 8-bpp images are much easier to work with than 1-bpp images +because they have a single byte per pixel: +<p> <pre> + QImage image; + // set entry 19 in the color table to yellow + image.<a href="#setColor">setColor</a>( 19, qRgb(255,255,0) ); + // set 8 bit pixel at (x,y) to value yellow (in color table) + *(image.<a href="#scanLine">scanLine</a>(y) + x) = 19; + </pre> + +<p> 32-bpp images ignore the color table; instead, each pixel contains +the RGB triplet. 24 bits contain the RGB value; the most +significant byte is reserved for the alpha buffer. +<p> <pre> + QImage image; + // sets 32 bit pixel at (x,y) to yellow. + uint *p = (uint *)image.<a href="#scanLine">scanLine</a>(y) + x; + *p = <a href="qcolor.html#qRgb">qRgb</a>(255,255,0); + </pre> + +<p> On Qt/Embedded, scanlines are aligned to the pixel depth and may +be padded to any degree, while on all other platforms, the +scanlines are 32-bit aligned for all depths. The constructor +taking a <tt>uchar*</tt> argument always expects 32-bit aligned data. +On Qt/Embedded, an additional constructor allows the number of +bytes-per-line to be specified. +<p> QImage supports a variety of methods for getting information about +the image, for example, <a href="#colorTable">colorTable</a>(), <a href="#allGray">allGray</a>(), <a href="#isGrayscale">isGrayscale</a>(), +<a href="#bitOrder">bitOrder</a>(), <a href="#bytesPerLine">bytesPerLine</a>(), <a href="#depth">depth</a>(), <a href="#dotsPerMeterX">dotsPerMeterX</a>() and +<a href="#dotsPerMeterY">dotsPerMeterY</a>(), <a href="#hasAlphaBuffer">hasAlphaBuffer</a>(), <a href="#numBytes">numBytes</a>(), <a href="#numColors">numColors</a>(), and +<a href="#width">width</a>() and <a href="#height">height</a>(). +<p> Pixel colors are retrieved with <a href="#pixel">pixel</a>() and set with <a href="#setPixel">setPixel</a>(). +<p> QImage also supports a number of functions for creating a new +image that is a transformed version of the original. For example, +<a href="#copy">copy</a>(), <a href="#convertBitOrder">convertBitOrder</a>(), <a href="#convertDepth">convertDepth</a>(), <a href="#createAlphaMask">createAlphaMask</a>(), +<a href="#createHeuristicMask">createHeuristicMask</a>(), <a href="#mirror">mirror</a>(), <a href="#scale">scale</a>(), <a href="#smoothScale">smoothScale</a>(), <a href="#swapRGB">swapRGB</a>() +and <a href="#xForm">xForm</a>(). There are also functions for changing attributes of +an image in-place, for example, <a href="#setAlphaBuffer">setAlphaBuffer</a>(), <a href="#setColor">setColor</a>(), +<a href="#setDotsPerMeterX">setDotsPerMeterX</a>() and <a href="#setDotsPerMeterY">setDotsPerMeterY</a>() and <a href="#setNumColors">setNumColors</a>(). +<p> Images can be loaded and saved in the supported formats. Images +are saved to a file with <a href="#save">save</a>(). Images are loaded from a file +with <a href="#load">load</a>() (or in the constructor) or from an array of data with +<a href="#loadFromData">loadFromData</a>(). The lists of supported formats are available from +<a href="#inputFormatList">inputFormatList</a>() and <a href="#outputFormatList">outputFormatList</a>(). +<p> Strings of text may be added to images using <a href="#setText">setText</a>(). +<p> The QImage class uses explicit <a href="shclass.html">sharing</a>, +similar to that used by <a href="qmemarray.html">QMemArray</a>. +<p> New image formats can be added as <a href="plugins-howto.html">plugins</a>. +<p> <p>See also <a href="qimageio.html">QImageIO</a>, <a href="qpixmap.html">QPixmap</a>, <a href="shclass.html">Shared Classes</a>, <a href="graphics.html">Graphics Classes</a>, <a href="images.html">Image Processing Classes</a>, and <a href="shared.html">Implicitly and Explicitly Shared Classes</a>. + +<hr><h2>Member Type Documentation</h2> +<h3 class=fn><a name="Endian-enum"></a>QImage::Endian</h3> + +<p> This enum type is used to describe the endianness of the CPU and +graphics hardware. +<ul> +<li><tt>QImage::IgnoreEndian</tt> - Endianness does not matter. Useful for some +operations that are independent of endianness. +<li><tt>QImage::BigEndian</tt> - Network byte order, as on SPARC and Motorola CPUs. +<li><tt>QImage::LittleEndian</tt> - PC/Alpha byte order. +</ul> +<h3 class=fn><a name="ScaleMode-enum"></a>QImage::ScaleMode</h3> + +<p> The functions <a href="#scale">scale</a>() and <a href="#smoothScale">smoothScale</a>() use different modes for +scaling the image. The purpose of these modes is to retain the +ratio of the image if this is required. +<p> <center><img src="scaling.png"></center> +<ul> +<li><tt>QImage::ScaleFree</tt> - The image is scaled freely: the resulting image +fits exactly into the specified size; the ratio will not +necessarily be preserved. +<li><tt>QImage::ScaleMin</tt> - The ratio of the image is preserved and the +resulting image is guaranteed to fit into the specified size +(it is as large as possible within these constraints) - the +image might be smaller than the requested size. +<li><tt>QImage::ScaleMax</tt> - The ratio of the image is preserved and the +resulting image fills the whole specified rectangle (it is as +small as possible within these constraints) - the image might +be larger than the requested size. +</ul> +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QImage"></a>QImage::QImage () +</h3> +Constructs a null image. +<p> <p>See also <a href="#isNull">isNull</a>(). + +<h3 class=fn><a name="QImage-2"></a>QImage::QImage ( int w, int h, int depth, int numColors = 0, <a href="qimage.html#Endian-enum">Endian</a> bitOrder = IgnoreEndian ) +</h3> +Constructs an image with <em>w</em> width, <em>h</em> height, <em>depth</em> bits +per pixel, <em>numColors</em> colors and bit order <em>bitOrder</em>. +<p> Using this constructor is the same as first constructing a null +image and then calling the <a href="#create">create</a>() function. +<p> <p>See also <a href="#create">create</a>(). + +<h3 class=fn><a name="QImage-3"></a>QImage::QImage ( const <a href="qsize.html">QSize</a> & size, int depth, int numColors = 0, <a href="qimage.html#Endian-enum">Endian</a> bitOrder = IgnoreEndian ) +</h3> +Constructs an image with size <em>size</em> pixels, depth <em>depth</em> bits, +<em>numColors</em> and <em>bitOrder</em> endianness. +<p> Using this constructor is the same as first constructing a null +image and then calling the <a href="#create">create</a>() function. +<p> <p>See also <a href="#create">create</a>(). + +<h3 class=fn><a name="QImage-4"></a>QImage::QImage ( const <a href="qstring.html">QString</a> & fileName, const char * format = 0 ) +</h3> +Constructs an image and tries to load the image from the file <em>fileName</em>. +<p> If <em>format</em> is specified, the loader attempts to read the image +using the specified format. If <em>format</em> is not specified (which +is the default), the loader reads a few bytes from the header to +guess the file format. +<p> If the loading of the image failed, this object is a <a href="#isNull">null</a> image. +<p> The <a href="qimageio.html">QImageIO</a> documentation lists the supported image formats and +explains how to add extra formats. +<p> <p>See also <a href="#load">load</a>(), <a href="#isNull">isNull</a>(), and <a href="qimageio.html">QImageIO</a>. + +<h3 class=fn><a name="QImage-5"></a>QImage::QImage ( const char * const xpm[] ) +</h3> +Constructs an image from <em>xpm</em>, which must be a valid XPM image. +<p> Errors are silently ignored. +<p> Note that it's possible to squeeze the XPM variable a little bit +by using an unusual declaration: +<p> <pre> + static const char * const start_xpm[]={ + "16 15 8 1", + "a c #cec6bd", + .... + </pre> + +<p> The extra <tt>const</tt> makes the entire definition read-only, which is +slightly more efficient (e.g. when the code is in a shared +library) and ROMable when the application is to be stored in ROM. + +<h3 class=fn><a name="QImage-6"></a>QImage::QImage ( const <a href="qbytearray.html">QByteArray</a> & array ) +</h3> +Constructs an image from the binary data <em>array</em>. It tries to +guess the file format. +<p> If the loading of the image failed, this object is a <a href="#isNull">null</a> image. +<p> <p>See also <a href="#loadFromData">loadFromData</a>(), <a href="#isNull">isNull</a>(), and <a href="#imageFormat">imageFormat</a>(). + +<h3 class=fn><a name="QImage-7"></a>QImage::QImage ( uchar * yourdata, int w, int h, int depth, QRgb * colortable, int numColors, <a href="qimage.html#Endian-enum">Endian</a> bitOrder ) +</h3> +Constructs an image <em>w</em> pixels wide, <em>h</em> pixels high with a +color depth of <em>depth</em>, that uses an existing memory buffer, <em>yourdata</em>. The buffer must remain valid throughout the life of the +QImage. The image does not delete the buffer at destruction. +<p> If <em>colortable</em> is 0, a color table sufficient for <em>numColors</em> +will be allocated (and destructed later). +<p> Note that <em>yourdata</em> must be 32-bit aligned. +<p> The endianness is given in <em>bitOrder</em>. + +<h3 class=fn><a name="QImage-8"></a>QImage::QImage ( uchar * yourdata, int w, int h, int depth, int bpl, QRgb * colortable, int numColors, <a href="qimage.html#Endian-enum">Endian</a> bitOrder ) +</h3> +Constructs an image that uses an existing memory buffer. The +buffer must remain valid for the life of the QImage. The image +does not delete the buffer at destruction. The buffer is passed as +<em>yourdata</em>. The image's width is <em>w</em> and its height is <em>h</em>. The +color depth is <em>depth</em>. <em>bpl</em> specifies the number of bytes per +line. +<p> If <em>colortable</em> is 0, a color table sufficient for <em>numColors</em> +will be allocated (and destructed later). +<p> The endianness is specified by <em>bitOrder</em>. +<p> <b>Warning:</b> This constructor is only available on Qt/Embedded. + +<h3 class=fn><a name="QImage-9"></a>QImage::QImage ( const <a href="qimage.html">QImage</a> & image ) +</h3> +Constructs a <a href="shclass.html">shallow copy</a> of <em>image</em>. + +<h3 class=fn><a name="~QImage"></a>QImage::~QImage () +</h3> +Destroys the image and cleans up. + +<h3 class=fn>bool <a name="allGray"></a>QImage::allGray () const +</h3> +Returns TRUE if all the colors in the image are shades of gray +(i.e. their red, green and blue components are equal); otherwise +returns FALSE. +<p> This function is slow for large 16-bit (Qt/Embedded only) and 32-bit images. +<p> <p>See also <a href="#isGrayscale">isGrayscale</a>(). + +<h3 class=fn><a href="qimage.html#Endian-enum">Endian</a> <a name="bitOrder"></a>QImage::bitOrder () const +</h3> + +<p> Returns the bit order for the image. +<p> If it is a 1-bpp image, this function returns either +QImage::BigEndian or QImage::LittleEndian. +<p> If it is not a 1-bpp image, this function returns +QImage::IgnoreEndian. +<p> <p>See also <a href="#depth">depth</a>(). + +<h3 class=fn>uchar * <a name="bits"></a>QImage::bits () const +</h3> + +<p> Returns a pointer to the first pixel data. This is equivalent to +<a href="#scanLine">scanLine</a>(0). +<p> <p>See also <a href="#numBytes">numBytes</a>(), <a href="#scanLine">scanLine</a>(), and <a href="#jumpTable">jumpTable</a>(). + +<p>Example: <a href="qglwidget.html#x2119">opengl/texture/gltexobj.cpp</a>. +<h3 class=fn>int <a name="bytesPerLine"></a>QImage::bytesPerLine () const +</h3> + +<p> Returns the number of bytes per image scanline. This is equivalent +to <a href="#numBytes">numBytes</a>()/height(). +<p> <p>See also <a href="#numBytes">numBytes</a>() and <a href="#scanLine">scanLine</a>(). + +<h3 class=fn>QRgb <a name="color"></a>QImage::color ( int i ) const +</h3> + +<p> Returns the color in the color table at index <em>i</em>. The first +color is at index 0. +<p> A color value is an RGB triplet. Use the <a href="qcolor.html#qRed">qRed()</a>, <a href="qcolor.html#qGreen">qGreen()</a> and <a href="qcolor.html#qBlue">qBlue()</a> functions (defined in <a href="qcolor-h.html">qcolor.h</a>) to +get the color value components. +<p> <p>See also <a href="#setColor">setColor</a>(), <a href="#numColors">numColors</a>(), and <a href="qcolor.html">QColor</a>. + +<p>Example: <a href="themes-example.html#x207">themes/wood.cpp</a>. +<h3 class=fn>QRgb * <a name="colorTable"></a>QImage::colorTable () const +</h3> + +<p> Returns a pointer to the color table. +<p> <p>See also <a href="#numColors">numColors</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="convertBitOrder"></a>QImage::convertBitOrder ( <a href="qimage.html#Endian-enum">Endian</a> bitOrder ) const +</h3> +Converts the bit order of the image to <em>bitOrder</em> and returns the +converted image. The original image is not changed. +<p> Returns <tt>*this</tt> if the <em>bitOrder</em> is equal to the image bit +order, or a <a href="#isNull">null</a> image if this image cannot +be converted. +<p> <p>See also <a href="#bitOrder">bitOrder</a>(), <a href="#systemBitOrder">systemBitOrder</a>(), and <a href="#isNull">isNull</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="convertDepth"></a>QImage::convertDepth ( int depth, int conversion_flags ) const +</h3> +Converts the depth (bpp) of the image to <em>depth</em> and returns the +converted image. The original image is not changed. +<p> The <em>depth</em> argument must be 1, 8, 16 (Qt/Embedded only) or 32. +<p> Returns <tt>*this</tt> if <em>depth</em> is equal to the image depth, or a +<a href="#isNull">null</a> image if this image cannot be +converted. +<p> If the image needs to be modified to fit in a lower-resolution +result (e.g. converting from 32-bit to 8-bit), use the <em>conversion_flags</em> to specify how you'd prefer this to happen. +<p> <p>See also <a href="qt.html#ImageConversionFlags-enum">Qt::ImageConversionFlags</a>, <a href="#depth">depth</a>(), and <a href="#isNull">isNull</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="convertDepth-2"></a>QImage::convertDepth ( int depth ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> +<h3 class=fn><a href="qimage.html">QImage</a> <a name="convertDepthWithPalette"></a>QImage::convertDepthWithPalette ( int d, QRgb * palette, int palette_count, int conversion_flags = 0 ) const +</h3> +Returns an image with depth <em>d</em>, using the <em>palette_count</em> +colors pointed to by <em>palette</em>. If <em>d</em> is 1 or 8, the returned +image will have its color table ordered the same as <em>palette</em>. +<p> If the image needs to be modified to fit in a lower-resolution +result (e.g. converting from 32-bit to 8-bit), use the <em>conversion_flags</em> to specify how you'd prefer this to happen. +<p> Note: currently no closest-color search is made. If colors are +found that are not in the palette, the palette may not be used at +all. This result should not be considered valid because it may +change in future implementations. +<p> Currently inefficient for non-32-bit images. +<p> <p>See also <a href="qt.html#ImageConversionFlags-enum">Qt::ImageConversionFlags</a>. + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="copy"></a>QImage::copy () const +</h3> +Returns a <a href="shclass.html">deep copy</a> of the image. +<p> <p>See also <a href="#detach">detach</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="copy-2"></a>QImage::copy ( int x, int y, int w, int h, int conversion_flags = 0 ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns a <a href="shclass.html">deep copy</a> of a sub-area of +the image. +<p> The returned image is always <em>w</em> by <em>h</em> pixels in size, and is +copied from position <em>x</em>, <em>y</em> in this image. In areas beyond +this image pixels are filled with pixel 0. +<p> If the image needs to be modified to fit in a lower-resolution +result (e.g. converting from 32-bit to 8-bit), use the <em>conversion_flags</em> to specify how you'd prefer this to happen. +<p> <p>See also <a href="#bitBlt">bitBlt</a>() and <a href="qt.html#ImageConversionFlags-enum">Qt::ImageConversionFlags</a>. + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="copy-3"></a>QImage::copy ( const <a href="qrect.html">QRect</a> & r ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns a <a href="shclass.html">deep copy</a> of a sub-area of +the image. +<p> The returned image always has the size of the rectangle <em>r</em>. In +areas beyond this image pixels are filled with pixel 0. + +<h3 class=fn>bool <a name="create"></a>QImage::create ( int width, int height, int depth, int numColors = 0, <a href="qimage.html#Endian-enum">Endian</a> bitOrder = IgnoreEndian ) +</h3> +Sets the image <em>width</em>, <em>height</em>, <em>depth</em>, its number of colors +(in <em>numColors</em>), and bit order. Returns TRUE if successful, or +FALSE if the parameters are incorrect or if memory cannot be +allocated. +<p> The <em>width</em> and <em>height</em> is limited to 32767. <em>depth</em> must be +1, 8, or 32. If <em>depth</em> is 1, <em>bitOrder</em> must be set to +either QImage::LittleEndian or QImage::BigEndian. For other depths +<em>bitOrder</em> must be QImage::IgnoreEndian. +<p> This function allocates a color table and a buffer for the image +data. The image data is not initialized. +<p> The image buffer is allocated as a single block that consists of a +table of <a href="#scanLine">scanline</a> pointers (<a href="#jumpTable">jumpTable</a>()) +and the image data (<a href="#bits">bits</a>()). +<p> <p>See also <a href="#fill">fill</a>(), <a href="#width">width</a>(), <a href="#height">height</a>(), <a href="#depth">depth</a>(), <a href="#numColors">numColors</a>(), <a href="#bitOrder">bitOrder</a>(), <a href="#jumpTable">jumpTable</a>(), <a href="#scanLine">scanLine</a>(), <a href="#bits">bits</a>(), <a href="#bytesPerLine">bytesPerLine</a>(), and <a href="#numBytes">numBytes</a>(). + +<h3 class=fn>bool <a name="create-2"></a>QImage::create ( const <a href="qsize.html">QSize</a> &, int depth, int numColors = 0, <a href="qimage.html#Endian-enum">Endian</a> bitOrder = IgnoreEndian ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> +<h3 class=fn><a href="qimage.html">QImage</a> <a name="createAlphaMask"></a>QImage::createAlphaMask ( int conversion_flags = 0 ) const +</h3> +Builds and returns a 1-bpp mask from the alpha buffer in this +image. Returns a <a href="#isNull">null</a> image if <a href="#setAlphaBuffer">alpha buffer mode</a> is disabled. +<p> See <a href="qpixmap.html#convertFromImage">QPixmap::convertFromImage</a>() for a description of the <em>conversion_flags</em> argument. +<p> The returned image has little-endian bit order, which you can +convert to big-endianness using <a href="#convertBitOrder">convertBitOrder</a>(). +<p> <p>See also <a href="#createHeuristicMask">createHeuristicMask</a>(), <a href="#hasAlphaBuffer">hasAlphaBuffer</a>(), and <a href="#setAlphaBuffer">setAlphaBuffer</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="createHeuristicMask"></a>QImage::createHeuristicMask ( bool clipTight = TRUE ) const +</h3> +Creates and returns a 1-bpp heuristic mask for this image. It +works by selecting a color from one of the corners, then chipping +away pixels of that color starting at all the edges. +<p> The four corners vote for which color is to be masked away. In +case of a draw (this generally means that this function is not +applicable to the image), the result is arbitrary. +<p> The returned image has little-endian bit order, which you can +convert to big-endianness using <a href="#convertBitOrder">convertBitOrder</a>(). +<p> If <em>clipTight</em> is TRUE the mask is just large enough to cover the +pixels; otherwise, the mask is larger than the data pixels. +<p> This function disregards the <a href="#hasAlphaBuffer">alpha buffer</a>. +<p> <p>See also <a href="#createAlphaMask">createAlphaMask</a>(). + +<h3 class=fn>int <a name="depth"></a>QImage::depth () const +</h3> + +<p> Returns the depth of the image. +<p> The image depth is the number of bits used to encode a single +pixel, also called bits per pixel (bpp) or bit planes of an image. +<p> The supported depths are 1, 8, 16 (Qt/Embedded only) and 32. +<p> <p>See also <a href="#convertDepth">convertDepth</a>(). + +<h3 class=fn>void <a name="detach"></a>QImage::detach () +</h3> +Detaches from shared image data and makes sure that this image is +the only one referring to the data. +<p> If multiple images share common data, this image makes a copy of +the data and detaches itself from the sharing mechanism. +Nothing is done if there is just a single reference. +<p> <p>See also <a href="#copy">copy</a>(). + +<p>Example: <a href="themes-example.html#x208">themes/wood.cpp</a>. +<h3 class=fn>int <a name="dotsPerMeterX"></a>QImage::dotsPerMeterX () const +</h3> + +<p> Returns the number of pixels that fit horizontally in a physical +meter. This and <a href="#dotsPerMeterY">dotsPerMeterY</a>() define the intended scale and +aspect ratio of the image. +<p> <p>See also <a href="#setDotsPerMeterX">setDotsPerMeterX</a>(). + +<h3 class=fn>int <a name="dotsPerMeterY"></a>QImage::dotsPerMeterY () const +</h3> + +<p> Returns the number of pixels that fit vertically in a physical +meter. This and <a href="#dotsPerMeterX">dotsPerMeterX</a>() define the intended scale and +aspect ratio of the image. +<p> <p>See also <a href="#setDotsPerMeterY">setDotsPerMeterY</a>(). + +<h3 class=fn>void <a name="fill"></a>QImage::fill ( uint pixel ) +</h3> +Fills the entire image with the pixel value <em>pixel</em>. +<p> If the <a href="#depth">depth</a> of this image is 1, only the +lowest bit is used. If you say <a href="#fill">fill</a>(0), fill(2), etc., the image +is filled with 0s. If you say fill(1), fill(3), etc., the image is +filled with 1s. If the depth is 8, the lowest 8 bits are used. +<p> If the depth is 32 and the image has no alpha buffer, the <em>pixel</em> +value is written to each pixel in the image. If the image has an +alpha buffer, only the 24 RGB bits are set and the upper 8 bits +(alpha value) are left unchanged. +<p> Note: <a href="#pixel">QImage::pixel</a>() returns the color of the pixel at the given +coordinates; <a href="qcolor.html#pixel">QColor::pixel</a>() returns the pixel value of the +underlying window system (essentially an index value), so normally +you will want to use QImage::pixel() to use a color from an +existing image or <a href="qcolor.html#rgb">QColor::rgb</a>() to use a specific color. +<p> <p>See also <a href="#invertPixels">invertPixels</a>(), <a href="#depth">depth</a>(), <a href="#hasAlphaBuffer">hasAlphaBuffer</a>(), and <a href="#create">create</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="fromMimeSource"></a>QImage::fromMimeSource ( const <a href="qstring.html">QString</a> & abs_name )<tt> [static]</tt> +</h3> Convenience function. Gets the data associated with the absolute +name <em>abs_name</em> from the default mime source factory and decodes it +to an image. +<p> <p>See also <a href="qmimesourcefactory.html">QMimeSourceFactory</a>, <a href="#fromMimeSource">QImage::fromMimeSource</a>(), and <a href="qimagedrag.html#decode">QImageDrag::decode</a>(). + +<h3 class=fn>bool <a name="hasAlphaBuffer"></a>QImage::hasAlphaBuffer () const +</h3> + +<p> Returns TRUE if alpha buffer mode is enabled; otherwise returns +FALSE. +<p> <p>See also <a href="#setAlphaBuffer">setAlphaBuffer</a>(). + +<h3 class=fn>int <a name="height"></a>QImage::height () const +</h3> + +<p> Returns the height of the image. +<p> <p>See also <a href="#width">width</a>(), <a href="#size">size</a>(), and <a href="#rect">rect</a>(). + +<p>Examples: <a href="canvas-example.html#x2932">canvas/canvas.cpp</a> and <a href="qglwidget.html#x2120">opengl/texture/gltexobj.cpp</a>. +<h3 class=fn>const char * <a name="imageFormat"></a>QImage::imageFormat ( const <a href="qstring.html">QString</a> & fileName )<tt> [static]</tt> +</h3> +Returns a string that specifies the image format of the file <em>fileName</em>, or 0 if the file cannot be read or if the format is not +recognized. +<p> The <a href="qimageio.html">QImageIO</a> documentation lists the guaranteed supported image +formats, or use <a href="#inputFormats">QImage::inputFormats</a>() and <a href="#outputFormats">QImage::outputFormats</a>() +to get lists that include the installed formats. +<p> <p>See also <a href="#load">load</a>() and <a href="#save">save</a>(). + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="inputFormatList"></a>QImage::inputFormatList ()<tt> [static]</tt> +</h3> +Returns a list of image formats that are supported for image +input. +<p> Note that if you want to iterate over the list, you should iterate +over a copy, e.g. +<pre> + <a href="qstringlist.html">QStringList</a> list = myImage.inputFormatList(); + QStringList::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>(); + while( it != list.<a href="qvaluelist.html#end">end</a>() ) { + myProcessing( *it ); + ++it; + } + </pre> + +<p> <p>See also <a href="#outputFormatList">outputFormatList</a>(), <a href="#inputFormats">inputFormats</a>(), and <a href="qimageio.html">QImageIO</a>. + +<p>Example: <a href="showimg-example.html#x1321">showimg/showimg.cpp</a>. +<h3 class=fn><a href="qstrlist.html">QStrList</a> <a name="inputFormats"></a>QImage::inputFormats ()<tt> [static]</tt> +</h3> +Returns a list of image formats that are supported for image +input. +<p> <p>See also <a href="#outputFormats">outputFormats</a>(), <a href="#inputFormatList">inputFormatList</a>(), and <a href="qimageio.html">QImageIO</a>. + +<h3 class=fn>void <a name="invertPixels"></a>QImage::invertPixels ( bool invertAlpha = TRUE ) +</h3> +Inverts all pixel values in the image. +<p> If the depth is 32: if <em>invertAlpha</em> is TRUE, the alpha bits are +also inverted, otherwise they are left unchanged. +<p> If the depth is not 32, the argument <em>invertAlpha</em> has no +meaning. +<p> Note that inverting an 8-bit image means to replace all pixels +using color index <em>i</em> with a pixel using color index 255 minus <em>i</em>. Similarly for a 1-bit image. The color table is not changed. +<p> <p>See also <a href="#fill">fill</a>(), <a href="#depth">depth</a>(), and <a href="#hasAlphaBuffer">hasAlphaBuffer</a>(). + +<h3 class=fn>bool <a name="isGrayscale"></a>QImage::isGrayscale () const +</h3> +For 16-bit (Qt/Embedded only) and 32-bit images, this function is +equivalent to <a href="#allGray">allGray</a>(). +<p> For 8-bpp images, this function returns TRUE if <a href="#color">color</a>(i) is +QRgb(i,i,i) for all indices of the color table; otherwise returns +FALSE. +<p> <p>See also <a href="#allGray">allGray</a>() and <a href="#depth">depth</a>(). + +<h3 class=fn>bool <a name="isNull"></a>QImage::isNull () const +</h3> + +<p> Returns TRUE if it is a null image; otherwise returns FALSE. +<p> A null image has all parameters set to zero and no allocated data. + +<p>Example: <a href="showimg-example.html#x1322">showimg/showimg.cpp</a>. +<h3 class=fn>uchar ** <a name="jumpTable"></a>QImage::jumpTable () const +</h3> + +<p> Returns a pointer to the scanline pointer table. +<p> This is the beginning of the data block for the image. +<p> <p>See also <a href="#bits">bits</a>() and <a href="#scanLine">scanLine</a>(). + +<h3 class=fn>bool <a name="load"></a>QImage::load ( const <a href="qstring.html">QString</a> & fileName, const char * format = 0 ) +</h3> +Loads an image from the file <em>fileName</em>. Returns TRUE if the +image was successfully loaded; otherwise returns FALSE. +<p> If <em>format</em> is specified, the loader attempts to read the image +using the specified format. If <em>format</em> is not specified (which +is the default), the loader reads a few bytes from the header to +guess the file format. +<p> The <a href="qimageio.html">QImageIO</a> documentation lists the supported image formats and +explains how to add extra formats. +<p> <p>See also <a href="#loadFromData">loadFromData</a>(), <a href="#save">save</a>(), <a href="#imageFormat">imageFormat</a>(), <a href="qpixmap.html#load">QPixmap::load</a>(), and <a href="qimageio.html">QImageIO</a>. + +<h3 class=fn>bool <a name="loadFromData"></a>QImage::loadFromData ( const uchar * buf, uint len, const char * format = 0 ) +</h3> +Loads an image from the first <em>len</em> bytes of binary data in <em>buf</em>. Returns TRUE if the image was successfully loaded; otherwise +returns FALSE. +<p> If <em>format</em> is specified, the loader attempts to read the image +using the specified format. If <em>format</em> is not specified (which +is the default), the loader reads a few bytes from the header to +guess the file format. +<p> The <a href="qimageio.html">QImageIO</a> documentation lists the supported image formats and +explains how to add extra formats. +<p> <p>See also <a href="#load">load</a>(), <a href="#save">save</a>(), <a href="#imageFormat">imageFormat</a>(), <a href="qpixmap.html#loadFromData">QPixmap::loadFromData</a>(), and <a href="qimageio.html">QImageIO</a>. + +<h3 class=fn>bool <a name="loadFromData-2"></a>QImage::loadFromData ( <a href="qbytearray.html">QByteArray</a> buf, const char * format = 0 ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Loads an image from the <a href="qbytearray.html">QByteArray</a> <em>buf</em>. + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="mirror"></a>QImage::mirror () const +</h3> +Returns a QImage which is a vertically mirrored copy of this +image. The original QImage is not changed. + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="mirror-2"></a>QImage::mirror ( bool horizontal, bool vertical ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns a mirror of the image, mirrored in the horizontal and/or +the vertical direction depending on whether <em>horizontal</em> and <em>vertical</em> are set to TRUE or FALSE. The original image is not +changed. +<p> <p>See also <a href="#smoothScale">smoothScale</a>(). + +<h3 class=fn>int <a name="numBytes"></a>QImage::numBytes () const +</h3> + +<p> Returns the number of bytes occupied by the image data. +<p> <p>See also <a href="#bytesPerLine">bytesPerLine</a>() and <a href="#bits">bits</a>(). + +<h3 class=fn>int <a name="numColors"></a>QImage::numColors () const +</h3> + +<p> Returns the size of the color table for the image. +<p> Notice that <a href="#numColors">numColors</a>() returns 0 for 16-bpp (Qt/Embedded only) +and 32-bpp images because these images do not use color tables, +but instead encode pixel values as RGB triplets. +<p> <p>See also <a href="#setNumColors">setNumColors</a>() and <a href="#colorTable">colorTable</a>(). + +<p>Example: <a href="themes-example.html#x209">themes/wood.cpp</a>. +<h3 class=fn><a href="qpoint.html">QPoint</a> <a name="offset"></a>QImage::offset () const +</h3> + +<p> Returns the number of pixels by which the image is intended to be +offset by when positioning relative to other images. + +<h3 class=fn>bool <a name="operator!-eq"></a>QImage::operator!= ( const <a href="qimage.html">QImage</a> & i ) const +</h3> +Returns TRUE if this image and image <em>i</em> have different contents; +otherwise returns FALSE. The comparison can be slow, unless there +is some obvious difference, such as different widths, in which +case the function will return quickly. +<p> <p>See also <a href="#operator-eq">operator=</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> & <a name="operator-eq"></a>QImage::operator= ( const <a href="qimage.html">QImage</a> & image ) +</h3> +Assigns a <a href="shclass.html">shallow copy</a> of <em>image</em> to +this image and returns a reference to this image. +<p> <p>See also <a href="#copy">copy</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> & <a name="operator-eq-2"></a>QImage::operator= ( const <a href="qpixmap.html">QPixmap</a> & pixmap ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Sets the image bits to the <em>pixmap</em> contents and returns a +reference to the image. +<p> If the image shares data with other images, it will first +dereference the shared data. +<p> Makes a call to <a href="qpixmap.html#convertToImage">QPixmap::convertToImage</a>(). + +<h3 class=fn>bool <a name="operator-eq-eq"></a>QImage::operator== ( const <a href="qimage.html">QImage</a> & i ) const +</h3> +Returns TRUE if this image and image <em>i</em> have the same contents; +otherwise returns FALSE. The comparison can be slow, unless there +is some obvious difference, such as different widths, in which +case the function will return quickly. +<p> <p>See also <a href="#operator-eq">operator=</a>(). + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="outputFormatList"></a>QImage::outputFormatList ()<tt> [static]</tt> +</h3> +Returns a list of image formats that are supported for image +output. +<p> Note that if you want to iterate over the list, you should iterate +over a copy, e.g. +<pre> + <a href="qstringlist.html">QStringList</a> list = myImage.outputFormatList(); + QStringList::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>(); + while( it != list.<a href="qvaluelist.html#end">end</a>() ) { + myProcessing( *it ); + ++it; + } + </pre> + +<p> <p>See also <a href="#inputFormatList">inputFormatList</a>(), <a href="#outputFormats">outputFormats</a>(), and <a href="qimageio.html">QImageIO</a>. + +<h3 class=fn><a href="qstrlist.html">QStrList</a> <a name="outputFormats"></a>QImage::outputFormats ()<tt> [static]</tt> +</h3> +Returns a list of image formats that are supported for image +output. +<p> <p>See also <a href="#inputFormats">inputFormats</a>(), <a href="#outputFormatList">outputFormatList</a>(), and <a href="qimageio.html">QImageIO</a>. + +<p>Example: <a href="showimg-example.html#x1323">showimg/showimg.cpp</a>. +<h3 class=fn>QRgb <a name="pixel"></a>QImage::pixel ( int x, int y ) const +</h3> +Returns the color of the pixel at the coordinates (<em>x</em>, <em>y</em>). +<p> If (<em>x</em>, <em>y</em>) is not <a href="#valid">on the image</a>, the +results are undefined. +<p> <p>See also <a href="#setPixel">setPixel</a>(), <a href="qcolor.html#qRed">qRed</a>(), <a href="qcolor.html#qGreen">qGreen</a>(), <a href="qcolor.html#qBlue">qBlue</a>(), and <a href="#valid">valid</a>(). + +<p>Examples: <a href="canvas-example.html#x2933">canvas/canvas.cpp</a> and <a href="qmag-example.html#x1776">qmag/qmag.cpp</a>. +<h3 class=fn>int <a name="pixelIndex"></a>QImage::pixelIndex ( int x, int y ) const +</h3> +Returns the pixel index at the given coordinates. +<p> If (<em>x</em>, <em>y</em>) is not <a href="#valid">valid</a>, or if the +image is not a paletted image (<a href="#depth">depth</a>() > 8), the results are +undefined. +<p> <p>See also <a href="#valid">valid</a>() and <a href="#depth">depth</a>(). + +<h3 class=fn><a href="qrect.html">QRect</a> <a name="rect"></a>QImage::rect () const +</h3> + +<p> Returns the enclosing rectangle (0, 0, <a href="#width">width</a>(), <a href="#height">height</a>()) of the +image. +<p> <p>See also <a href="#width">width</a>(), <a href="#height">height</a>(), and <a href="#size">size</a>(). + +<h3 class=fn>void <a name="reset"></a>QImage::reset () +</h3> +Resets all image parameters and deallocates the image data. + +<h3 class=fn>bool <a name="save"></a>QImage::save ( const <a href="qstring.html">QString</a> & fileName, const char * format, int quality = -1 ) const +</h3> +Saves the image to the file <em>fileName</em>, using the image file +format <em>format</em> and a quality factor of <em>quality</em>. <em>quality</em> +must be in the range 0..100 or -1. Specify 0 to obtain small +compressed files, 100 for large uncompressed files, and -1 (the +default) to use the default settings. +<p> Returns TRUE if the image was successfully saved; otherwise +returns FALSE. +<p> <p>See also <a href="#load">load</a>(), <a href="#loadFromData">loadFromData</a>(), <a href="#imageFormat">imageFormat</a>(), <a href="qpixmap.html#save">QPixmap::save</a>(), and <a href="qimageio.html">QImageIO</a>. + +<h3 class=fn>bool <a name="save-2"></a>QImage::save ( <a href="qiodevice.html">QIODevice</a> * device, const char * format, int quality = -1 ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> This function writes a QImage to the <a href="qiodevice.html">QIODevice</a>, <em>device</em>. This +can be used, for example, to save an image directly into a +QByteArray: +<pre> + QImage image; + <a href="qbytearray.html">QByteArray</a> ba; + <a href="qbuffer.html">QBuffer</a> buffer( ba ); + buffer.<a href="qiodevice.html#open">open</a>( <a href="qfile.html#open">IO_WriteOnly</a> ); + image.<a href="#save">save</a>( &buffer, "PNG" ); // writes image into ba in PNG format + </pre> + + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="scale"></a>QImage::scale ( int w, int h, <a href="qimage.html#ScaleMode-enum">ScaleMode</a> mode = ScaleFree ) const +</h3> +Returns a copy of the image scaled to a rectangle of width <em>w</em> +and height <em>h</em> according to the ScaleMode <em>mode</em>. +<p> <ul> +<li> If <em>mode</em> is <a href="#ScaleMode-enum">ScaleFree</a>, the image is scaled to (<em>w</em>, +<em>h</em>). +<li> If <em>mode</em> is <a href="#ScaleMode-enum">ScaleMin</a>, the image is scaled to a rectangle +as large as possible inside (<em>w</em>, <em>h</em>), preserving the aspect +ratio. +<li> If <em>mode</em> is <a href="#ScaleMode-enum">ScaleMax</a>, the image is scaled to a rectangle +as small as possible outside (<em>w</em>, <em>h</em>), preserving the aspect +ratio. +</ul> +<p> If either the width <em>w</em> or the height <em>h</em> is 0 or negative, this +function returns a <a href="#isNull">null</a> image. +<p> This function uses a simple, fast algorithm. If you need better +quality, use <a href="#smoothScale">smoothScale</a>() instead. +<p> <p>See also <a href="#scaleWidth">scaleWidth</a>(), <a href="#scaleHeight">scaleHeight</a>(), <a href="#smoothScale">smoothScale</a>(), and <a href="#xForm">xForm</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="scale-2"></a>QImage::scale ( const <a href="qsize.html">QSize</a> & s, <a href="qimage.html#ScaleMode-enum">ScaleMode</a> mode = ScaleFree ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> The requested size of the image is <em>s</em>. + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="scaleHeight"></a>QImage::scaleHeight ( int h ) const +</h3> +Returns a scaled copy of the image. The returned image has a +height of <em>h</em> pixels. This function automatically calculates the +width of the image so that the ratio of the image is preserved. +<p> If <em>h</em> is 0 or negative a <a href="#isNull">null</a> image is +returned. +<p> <p>See also <a href="#scale">scale</a>(), <a href="#scaleWidth">scaleWidth</a>(), <a href="#smoothScale">smoothScale</a>(), and <a href="#xForm">xForm</a>(). + +<p>Example: <a href="small-table-example-example.html#x2799">table/small-table-demo/main.cpp</a>. +<h3 class=fn><a href="qimage.html">QImage</a> <a name="scaleWidth"></a>QImage::scaleWidth ( int w ) const +</h3> +Returns a scaled copy of the image. The returned image has a width +of <em>w</em> pixels. This function automatically calculates the height +of the image so that the ratio of the image is preserved. +<p> If <em>w</em> is 0 or negative a <a href="#isNull">null</a> image is +returned. +<p> <p>See also <a href="#scale">scale</a>(), <a href="#scaleHeight">scaleHeight</a>(), <a href="#smoothScale">smoothScale</a>(), and <a href="#xForm">xForm</a>(). + +<h3 class=fn>uchar * <a name="scanLine"></a>QImage::scanLine ( int i ) const +</h3> + +<p> Returns a pointer to the pixel data at the scanline with index <em>i</em>. The first scanline is at index 0. +<p> The scanline data is aligned on a 32-bit boundary. +<p> <b>Warning:</b> If you are accessing 32-bpp image data, cast the returned +pointer to <tt>QRgb*</tt> (QRgb has a 32-bit size) and use it to +read/write the pixel value. You cannot use the <tt>uchar*</tt> pointer +directly, because the pixel format depends on the byte order on +the underlying platform. Hint: use <a href="qcolor.html#qRed">qRed()</a>, +<a href="qcolor.html#qGreen">qGreen()</a> and <a href="qcolor.html#qBlue">qBlue()</a>, etc. (qcolor.h) to access the pixels. +<p> <b>Warning:</b> If you are accessing 16-bpp image data, you must handle +endianness yourself. (Qt/Embedded only) +<p> <p>See also <a href="#bytesPerLine">bytesPerLine</a>(), <a href="#bits">bits</a>(), and <a href="#jumpTable">jumpTable</a>(). + +<p>Example: <a href="desktop-example.html#x1729">desktop/desktop.cpp</a>. +<h3 class=fn>void <a name="setAlphaBuffer"></a>QImage::setAlphaBuffer ( bool enable ) +</h3> +Enables alpha buffer mode if <em>enable</em> is TRUE, otherwise disables +it. The default setting is disabled. +<p> An 8-bpp image has 8-bit pixels. A pixel is an index into the +<a href="#color">color table</a>, which contains 32-bit color +values. In a 32-bpp image, the 32-bit pixels are the color values. +<p> This 32-bit value is encoded as follows: The lower 24 bits are +used for the red, green, and blue components. The upper 8 bits +contain the alpha component. +<p> The alpha component specifies the transparency of a pixel. 0 means +completely transparent and 255 means opaque. The alpha component +is ignored if you do not enable alpha buffer mode. +<p> The alpha buffer is used to set a mask when a QImage is translated +to a <a href="qpixmap.html">QPixmap</a>. +<p> <p>See also <a href="#hasAlphaBuffer">hasAlphaBuffer</a>() and <a href="#createAlphaMask">createAlphaMask</a>(). + +<h3 class=fn>void <a name="setColor"></a>QImage::setColor ( int i, QRgb c ) +</h3> + +<p> Sets a color in the color table at index <em>i</em> to <em>c</em>. +<p> A color value is an RGB triplet. Use the <a href="qcolor.html#qRgb">qRgb()</a> function (defined in <a href="qcolor-h.html">qcolor.h</a>) to make RGB +triplets. +<p> <p>See also <a href="#color">color</a>(), <a href="#setNumColors">setNumColors</a>(), and <a href="#numColors">numColors</a>(). + +<p>Examples: <a href="desktop-example.html#x1730">desktop/desktop.cpp</a> and <a href="themes-example.html#x210">themes/wood.cpp</a>. +<h3 class=fn>void <a name="setDotsPerMeterX"></a>QImage::setDotsPerMeterX ( int x ) +</h3> +Sets the value returned by <a href="#dotsPerMeterX">dotsPerMeterX</a>() to <em>x</em>. + +<h3 class=fn>void <a name="setDotsPerMeterY"></a>QImage::setDotsPerMeterY ( int y ) +</h3> +Sets the value returned by <a href="#dotsPerMeterY">dotsPerMeterY</a>() to <em>y</em>. + +<h3 class=fn>void <a name="setNumColors"></a>QImage::setNumColors ( int numColors ) +</h3> +Resizes the color table to <em>numColors</em> colors. +<p> If the color table is expanded all the extra colors will be set to +black (RGB 0,0,0). +<p> <p>See also <a href="#numColors">numColors</a>(), <a href="#color">color</a>(), <a href="#setColor">setColor</a>(), and <a href="#colorTable">colorTable</a>(). + +<h3 class=fn>void <a name="setOffset"></a>QImage::setOffset ( const <a href="qpoint.html">QPoint</a> & p ) +</h3> +Sets the value returned by <a href="#offset">offset</a>() to <em>p</em>. + +<h3 class=fn>void <a name="setPixel"></a>QImage::setPixel ( int x, int y, uint index_or_rgb ) +</h3> +Sets the pixel index or color at the coordinates (<em>x</em>, <em>y</em>) to +<em>index_or_rgb</em>. +<p> If (<em>x</em>, <em>y</em>) is not <a href="#valid">valid</a>, the result is +undefined. +<p> If the image is a paletted image (<a href="#depth">depth</a>() <= 8) and <em>index_or_rgb</em> >= <a href="#numColors">numColors</a>(), the result is undefined. +<p> <p>See also <a href="#pixelIndex">pixelIndex</a>(), <a href="#pixel">pixel</a>(), <a href="qcolor.html#qRgb">qRgb</a>(), <a href="qcolor.html#qRgba">qRgba</a>(), and <a href="#valid">valid</a>(). + +<h3 class=fn>void <a name="setText"></a>QImage::setText ( const char * key, const char * lang, const <a href="qstring.html">QString</a> & s ) +</h3> +Records string <em>s</em> for the keyword <em>key</em>. The <em>key</em> should be a +portable keyword recognizable by other software - some suggested +values can be found in <a href="http://www.libpng.org/pub/png/spec/1.2/png-1.2-pdg.html#C.Anc-text">the PNG specification</a>. <em>s</em> can be any text. <em>lang</em> +should specify the language code (see +<a href="http://www.rfc-editor.org/rfc/rfc1766.txt">RFC 1766</a>) or 0. + +<h3 class=fn><a href="qsize.html">QSize</a> <a name="size"></a>QImage::size () const +</h3> + +<p> Returns the size of the image, i.e. its width and height. +<p> <p>See also <a href="#width">width</a>(), <a href="#height">height</a>(), and <a href="#rect">rect</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="smoothScale"></a>QImage::smoothScale ( int w, int h, <a href="qimage.html#ScaleMode-enum">ScaleMode</a> mode = ScaleFree ) const +</h3> +Returns a smoothly scaled copy of the image. The returned image +has a size of width <em>w</em> by height <em>h</em> pixels if <em>mode</em> is <a href="#ScaleMode-enum">ScaleFree</a>. The modes <a href="#ScaleMode-enum">ScaleMin</a> and <a href="#ScaleMode-enum">ScaleMax</a> may be used to +preserve the ratio of the image: if <em>mode</em> is <a href="#ScaleMode-enum">ScaleMin</a>, the +returned image is guaranteed to fit into the rectangle specified +by <em>w</em> and <em>h</em> (it is as large as possible within the +constraints); if <em>mode</em> is <a href="#ScaleMode-enum">ScaleMax</a>, the returned image fits +at least into the specified rectangle (it is a small as possible +within the constraints). +<p> For 32-bpp images and 1-bpp/8-bpp color images the result will be +32-bpp, whereas <a href="#allGray">all-gray</a> images +(including black-and-white 1-bpp) will produce 8-bit <a href="#isGrayscale">grayscale</a> images with the palette spanning +256 grays from black to white. +<p> This function uses code based on pnmscale.c by Jef Poskanzer. +<p> pnmscale.c - read a portable anymap and scale it +<p> +<p> Copyright (C) 1989, 1991 by Jef Poskanzer. +<p> Permission to use, copy, modify, and distribute this software and +its documentation for any purpose and without fee is hereby +granted, provided that the above copyright notice appear in all +copies and that both that copyright notice and this permission +notice appear in supporting documentation. This software is +provided "as is" without express or implied warranty. +<p> <p>See also <a href="#scale">scale</a>() and <a href="#mirror">mirror</a>(). + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="smoothScale-2"></a>QImage::smoothScale ( const <a href="qsize.html">QSize</a> & s, <a href="qimage.html#ScaleMode-enum">ScaleMode</a> mode = ScaleFree ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> The requested size of the image is <em>s</em>. + +<h3 class=fn><a href="qimage.html">QImage</a> <a name="swapRGB"></a>QImage::swapRGB () const +</h3> +Returns a QImage in which the values of the red and blue +components of all pixels have been swapped, effectively converting +an RGB image to a BGR image. The original QImage is not changed. + +<h3 class=fn><a href="qimage.html#Endian-enum">Endian</a> <a name="systemBitOrder"></a>QImage::systemBitOrder ()<tt> [static]</tt> +</h3> +Determines the bit order of the display hardware. Returns +QImage::LittleEndian (LSB first) or QImage::BigEndian (MSB first). +<p> <p>See also <a href="#systemByteOrder">systemByteOrder</a>(). + +<h3 class=fn><a href="qimage.html#Endian-enum">Endian</a> <a name="systemByteOrder"></a>QImage::systemByteOrder ()<tt> [static]</tt> +</h3> +Determines the host computer byte order. Returns +QImage::LittleEndian (LSB first) or QImage::BigEndian (MSB first). +<p> <p>See also <a href="#systemBitOrder">systemBitOrder</a>(). + +<h3 class=fn><a href="qstring.html">QString</a> <a name="text"></a>QImage::text ( const char * key, const char * lang = 0 ) const +</h3> +Returns the string recorded for the keyword <em>key</em> in language <em>lang</em>, or in a default language if <em>lang</em> is 0. + +<h3 class=fn><a href="qstring.html">QString</a> <a name="text-2"></a>QImage::text ( const QImageTextKeyLang & kl ) const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns the string recorded for the keyword and language <em>kl</em>. + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="textKeys"></a>QImage::textKeys () const +</h3> +Returns the keywords for which some texts are recorded. +<p> Note that if you want to iterate over the list, you should iterate +over a copy, e.g. +<pre> + <a href="qstringlist.html">QStringList</a> list = myImage.textKeys(); + QStringList::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>(); + while( it != list.<a href="qvaluelist.html#end">end</a>() ) { + myProcessing( *it ); + ++it; + } + </pre> + +<p> <p>See also <a href="#textList">textList</a>(), <a href="#text">text</a>(), <a href="#setText">setText</a>(), and <a href="#textLanguages">textLanguages</a>(). + +<h3 class=fn><a href="qstringlist.html">QStringList</a> <a name="textLanguages"></a>QImage::textLanguages () const +</h3> +Returns the language identifiers for which some texts are +recorded. +<p> Note that if you want to iterate over the list, you should iterate +over a copy, e.g. +<pre> + <a href="qstringlist.html">QStringList</a> list = myImage.textLanguages(); + QStringList::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>(); + while( it != list.<a href="qvaluelist.html#end">end</a>() ) { + myProcessing( *it ); + ++it; + } + </pre> + +<p> <p>See also <a href="#textList">textList</a>(), <a href="#text">text</a>(), <a href="#setText">setText</a>(), and <a href="#textKeys">textKeys</a>(). + +<h3 class=fn><a href="qvaluelist.html">QValueList</a><QImageTextKeyLang> <a name="textList"></a>QImage::textList () const +</h3> +Returns a list of QImageTextKeyLang objects that enumerate all the +texts key/language pairs set by <a href="#setText">setText</a>() for this image. +<p> Note that if you want to iterate over the list, you should iterate +over a copy, e.g. +<pre> + <a href="qvaluelist.html">QValueList</a><QImageTextKeyLang> list = myImage.textList(); + QValueList<QImageTextKeyLang>::Iterator it = list.<a href="qvaluelist.html#begin">begin</a>(); + while( it != list.<a href="qvaluelist.html#end">end</a>() ) { + myProcessing( *it ); + ++it; + } + </pre> + + +<h3 class=fn>bool <a name="valid"></a>QImage::valid ( int x, int y ) const +</h3> +Returns TRUE if ( <em>x</em>, <em>y</em> ) is a valid coordinate in the image; +otherwise returns FALSE. +<p> <p>See also <a href="#width">width</a>(), <a href="#height">height</a>(), and <a href="#pixelIndex">pixelIndex</a>(). + +<p>Examples: <a href="canvas-example.html#x2934">canvas/canvas.cpp</a> and <a href="qmag-example.html#x1777">qmag/qmag.cpp</a>. +<h3 class=fn>int <a name="width"></a>QImage::width () const +</h3> + +<p> Returns the width of the image. +<p> <p>See also <a href="#height">height</a>(), <a href="#size">size</a>(), and <a href="#rect">rect</a>(). + +<p>Examples: <a href="canvas-example.html#x2935">canvas/canvas.cpp</a> and <a href="qglwidget.html#x2121">opengl/texture/gltexobj.cpp</a>. +<h3 class=fn><a href="qimage.html">QImage</a> <a name="xForm"></a>QImage::xForm ( const <a href="qwmatrix.html">QWMatrix</a> & matrix ) const +</h3> +Returns a copy of the image that is transformed using the +<a href="qwmatrix.html#TransformationMode">transformation matrix</a>, <em>matrix</em>. +<p> The transformation <em>matrix</em> is internally adjusted to compensate +for unwanted translation, i.e. <a href="#xForm">xForm</a>() returns the smallest image +that contains all the transformed points of the original image. +<p> <p>See also <a href="#scale">scale</a>(), <a href="qpixmap.html#xForm">QPixmap::xForm</a>(), <a href="qpixmap.html#trueMatrix">QPixmap::trueMatrix</a>(), and <a href="qwmatrix.html">QWMatrix</a>. + +<hr><h2>Related Functions</h2> +<h3 class=fn>void <a name="bitBlt"></a>bitBlt ( <a href="qimage.html">QImage</a> * dst, int dx, int dy, const <a href="qimage.html">QImage</a> * src, int sx, int sy, int sw, int sh, int conversion_flags ) +</h3> + +<p> Copies a block of pixels from <em>src</em> to <em>dst</em>. The pixels +copied from source (src) are converted according to +<em>conversion_flags</em> if it is incompatible with the destination +(<em>dst</em>). +<p> <em>sx</em>, <em>sy</em> is the top-left pixel in <em>src</em>, <em>dx</em>, <em>dy</em> +is the top-left position in <em>dst</em> and <em>sw</em>, \sh is the +size of the copied block. +<p> The copying is clipped if areas outside <em>src</em> or <em>dst</em> are +specified. +<p> If <em>sw</em> is -1, it is adjusted to src->width(). Similarly, if <em>sh</em> is -1, it is adjusted to src->height(). +<p> Currently inefficient for non 32-bit images. + +<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-lt-lt"></a>operator<< ( <a href="qdatastream.html">QDataStream</a> & s, const <a href="qimage.html">QImage</a> & image ) +</h3> + +<p> Writes the image <em>image</em> to the stream <em>s</em> as a PNG image, or as a +BMP image if the stream's version is 1. +<p> Note that writing the stream to a file will not produce a valid image file. +<p> <p>See also <a href="#save">QImage::save</a>() and <a href="datastreamformat.html">Format of the QDataStream operators</a>. + +<h3 class=fn><a href="qdatastream.html">QDataStream</a> & <a name="operator-gt-gt"></a>operator>> ( <a href="qdatastream.html">QDataStream</a> & s, <a href="qimage.html">QImage</a> & image ) +</h3> + +<p> Reads an image from the stream <em>s</em> and stores it in <em>image</em>. +<p> <p>See also <a href="#load">QImage::load</a>() and <a href="datastreamformat.html">Format of the QDataStream operators</a>. + +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. 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