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RedHat 9 (Linux i386) - man page for qimage (redhat section 3qt)

QImage(3qt)									      QImage(3qt)

NAME
       QImage - Hardware-independent pixmap representation with direct access to the pixel data

SYNOPSIS
       #include <qimage.h>

   Public Members
       enum Endian { IgnoreEndian, BigEndian, LittleEndian }
       QImage ()
       QImage ( int w, int h, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian )
       QImage ( const QSize & size, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian
	   )
       QImage ( const QString & fileName, const char * format = 0 )
       QImage ( const char * const xpm[] )
       QImage ( const QByteArray & array )
       QImage ( uchar * yourdata, int w, int h, int depth, QRgb * colortable, int numColors,
	   Endian bitOrder )
       QImage ( uchar * yourdata, int w, int h, int depth, int bpl, QRgb * colortable, int
	   numColors, Endian bitOrder )
       QImage ( const QImage & image )
       ~QImage ()
       QImage & operator= ( const QImage & image )
       QImage & operator= ( const QPixmap & pixmap )
       bool operator== ( const QImage & i ) const
       bool operator!= ( const QImage & i ) const
       void detach ()
       QImage copy () const
       QImage copy ( int x, int y, int w, int h, int conversion_flags = 0 ) const
       QImage copy ( const QRect & r ) const
       bool isNull () const
       int width () const
       int height () const
       QSize size () const
       QRect rect () const
       int depth () const
       int numColors () const
       Endian bitOrder () const
       QRgb color ( int i ) const
       void setColor ( int i, QRgb c )
       void setNumColors ( int numColors )
       bool hasAlphaBuffer () const
       void setAlphaBuffer ( bool enable )
       bool allGray () const
       bool isGrayscale () const
       uchar * bits () const
       uchar * scanLine ( int i ) const
       uchar ** jumpTable () const
       QRgb * colorTable () const
       int numBytes () const
       int bytesPerLine () const
       bool create ( int width, int height, int depth, int numColors = 0, Endian bitOrder =
	   IgnoreEndian )
       bool create ( const QSize &, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian
	   )
       void reset ()
       void fill ( uint pixel )
       void invertPixels ( bool invertAlpha = TRUE )
       QImage convertDepth ( int depth ) const
       QImage convertDepthWithPalette ( int d, QRgb * palette, int palette_count, int
	   conversion_flags = 0 ) const
       QImage convertDepth ( int depth, int conversion_flags ) const
       QImage convertBitOrder ( Endian bitOrder ) const
       enum ScaleMode { ScaleFree, ScaleMin, ScaleMax }
       QImage smoothScale ( int w, int h, ScaleMode mode = ScaleFree ) const
       QImage smoothScale ( const QSize & s, ScaleMode mode = ScaleFree ) const
       QImage scale ( int w, int h, ScaleMode mode = ScaleFree ) const
       QImage scale ( const QSize & s, ScaleMode mode = ScaleFree ) const
       QImage scaleWidth ( int w ) const
       QImage scaleHeight ( int h ) const
       QImage xForm ( const QWMatrix & matrix ) const
       QImage createAlphaMask ( int conversion_flags = 0 ) const
       QImage createHeuristicMask ( bool clipTight = TRUE ) const
       QImage mirror () const
       QImage mirror ( bool horizontal, bool vertical ) const
       QImage swapRGB () const
       bool load ( const QString & fileName, const char * format = 0 )
       bool loadFromData ( const uchar * buf, uint len, const char * format = 0 )
       bool loadFromData ( QByteArray buf, const char * format = 0 )
       bool save ( const QString & fileName, const char * format, int quality = -1 ) const
       bool valid ( int x, int y ) const
       int pixelIndex ( int x, int y ) const
       QRgb pixel ( int x, int y ) const
       void setPixel ( int x, int y, uint index_or_rgb )
       int dotsPerMeterX () const
       int dotsPerMeterY () const
       void setDotsPerMeterX ( int x )
       void setDotsPerMeterY ( int y )
       QPoint offset () const
       void setOffset ( const QPoint & p )
       QValueList<QImageTextKeyLang> textList () const
       QStringList textLanguages () const
       QStringList textKeys () const
       QString text ( const char * key, const char * lang = 0 ) const
       QString text ( const QImageTextKeyLang & kl ) const
       void setText ( const char * key, const char * lang, const QString & s )

   Static Public Members
       QImage fromMimeSource ( const QString & abs_name )
       Endian systemBitOrder ()
       Endian systemByteOrder ()
       const char * imageFormat ( const QString & fileName )
       QStrList inputFormats ()
       QStrList outputFormats ()
       QStringList inputFormatList ()
       QStringList outputFormatList ()

RELATED FUNCTION DOCUMENTATION
       QDataStream & operator<< ( QDataStream & s, const QImage & image )
       QDataStream & operator>> ( QDataStream & s, QImage & image )

DESCRIPTION
       The QImage class provides a hardware-independent pixmap representation with direct access
       to the pixel data.

       It is one of the two classes Qt provides for dealing with images, the other being QPixmap.
       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: QPixmap::convertToImage() and QPixmap::convertFromImage().

       An image has the parameters width, height and depth (bits per pixel, bpp), a color table
       and the actual pixels. 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.

       32-bpp images encode an RGB value in 24 bits and ignore the color table. The most
       significant byte is used for the alpha buffer.

       An entry in the color table is an RGB triplet encoded as a uint. Use the qRed(), qGreen()
       and qBlue() functions (qcolor.h) to access the components, and qRgb to make an RGB triplet
       (see the QColor class documentation).

       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:

	   QImage image;
	   // sets bit at (x,y) to 1
	   if ( image.bitOrder() == QImage::LittleEndian )
	       *(image.scanLine(y) + (x >> 3)) |= 1 << (x & 7);
	   else
	       *(image.scanLine(y) + (x >> 3)) |= 1 << (7 - (x & 7));

       If this looks complicated, it might be a good idea to convert the 1-bpp image to an 8-bpp
       image using convertDepth().

       8-bpp images are much easier to work with than 1-bpp images because they have a single
       byte per pixel:

	   QImage image;
	   // set entry 19 in the color table to yellow
	   image.setColor( 19, qRgb(255,255,0) );
	   // set 8 bit pixel at (x,y) to value yellow (in color table)
	   *(image.scanLine(y) + x) = 19;

       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.

	   QImage image;
	   // sets 32 bit pixel at (x,y) to yellow.
	   uint *p = (uint *)image.scanLine(y) + x;
	   *p = qRgb(255,255,0);

       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 uchar* argument always expects 32-bit aligned data. On Qt/Embedded,
       an additional constructor allows the number of bytes-per-line to be specified.

       QImage supports a variety of methods for getting information about the image, for example,
       colorTable(), allGray(), isGrayscale(), bitOrder(), bytesPerLine(), depth(),
       dotsPerMeterX() and dotsPerMeterY(), hasAlphaBuffer(), numBytes(), numColors(), and
       width() and height().

       Pixel colors are retrieved with pixel() and set with setPixel().

       QImage also supports a number of functions for creating a new image that is a transformed
       version of the original. For example, copy(), convertBitOrder(), convertDepth(),
       createAlphaMask(), createHeuristicMask(), mirror(), scale(), smoothScale(), swapRGB() and
       xForm(). There are also functions for changing attributes of an image in-place, for
       example, setAlphaBuffer(), setColor(), setDotsPerMeterX() and setDotsPerMeterY() and
       setNumColors().

       Images can be loaded and saved in the supported formats. Images are saved to a file with
       save(). Images are loaded from a file with load() (or in the constructor) or from an array
       of data with loadFromData(). The lists of supported formats are available from
       inputFormatList() and outputFormatList().

       Strings of text may be added to images using setText().

       The QImage class uses explicit sharing, similar to that used by QMemArray.

       New image formats can be added as plugins.

       See also QImageIO, QPixmap, Shared Classes, Graphics Classes, Image Processing Classes,
       and Implicitly and Explicitly Shared Classes.

   Member Type Documentation
QImage::Endian
       This enum type is used to describe the endianness of the CPU and graphics hardware.

       QImage::IgnoreEndian - Endianness does not matter. Useful for some operations that are
       independent of endianness.

       QImage::BigEndian - Network byte order, as on SPARC and Motorola CPUs.

       QImage::LittleEndian - PC/Alpha byte order.

QImage::ScaleMode
       The functions scale() and smoothScale() use different modes for scaling the image. The
       purpose of these modes is to retain the ratio of the image if this is required.

       <center>
					    [Image Omitted]

       </center>

       QImage::ScaleFree - The image is scaled freely: the resulting image fits exactly into the
       specified size; the ratio will not necessarily be preserved.

       QImage::ScaleMin - 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.

       QImage::ScaleMax - 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.

MEMBER FUNCTION DOCUMENTATION
QImage::QImage ()
       Constructs a null image.

       See also isNull().

QImage::QImage ( int w, int h, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian )
       Constructs an image with w width, h height, depth bits per pixel, numColors colors and bit
       order bitOrder.

       Using this constructor is the same as first constructing a null image and then calling the
       create() function.

       See also create().

QImage::QImage ( const QSize & size, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian
       )
       Constructs an image with size size pixels, depth depth bits, numColors and bitOrder
       endianness.

       Using this constructor is the same as first constructing a null image and then calling the
       create() function.

       See also create().

QImage::QImage ( const QString & fileName, const char * format = 0 )
       Constructs an image and tries to load the image from the file fileName.

       If format is specified, the loader attempts to read the image using the specified format.
       If format is not specified (which is the default), the loader reads a few bytes from the
       header to guess the file format.

       If the loading of the image failed, this object is a null image.

       The QImageIO documentation lists the supported image formats and explains how to add extra
       formats.

       See also load(), isNull(), and QImageIO.

QImage::QImage ( const char * const xpm[] )
       Constructs an image from xpm, which must be a valid XPM image.

       Errors are silently ignored.

       Note that it's possible to squeeze the XPM variable a little bit by using an unusual
       declaration:

	       static const char * const start_xpm[]={
		   "16 15 8 1",
		   "a c #cec6bd",
	       ....

       The extra const 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.

QImage::QImage ( const QByteArray & array )
       Constructs an image from the binary data array. It tries to guess the file format.

       If the loading of the image failed, this object is a null image.

       See also loadFromData(), isNull(), and imageFormat().

QImage::QImage ( uchar * yourdata, int w, int h, int depth, QRgb * colortable, int numColors,
       Endian bitOrder )
       Constructs an image w pixels wide, h pixels high with a color depth of depth, that uses an
       existing memory buffer, yourdata. The buffer must remain valid throughout the life of the
       QImage. The image does not delete the buffer at destruction.

       If colortable is 0, a color table sufficient for numColors will be allocated (and
       destructed later).

       Note that yourdata must be 32-bit aligned.

       The endianness is given in bitOrder.

QImage::QImage ( uchar * yourdata, int w, int h, int depth, int bpl, QRgb * colortable, int
       numColors, Endian bitOrder )
       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 yourdata. The image's width is w and its height is h. The color depth is depth.
       bpl specifies the number of bytes per line.

       If colortable is 0, a color table sufficient for numColors will be allocated (and
       destructed later).

       The endian-ness is specified by bitOrder.

QImage::QImage ( const QImage & image )
       Constructs a shallow copy of image.

QImage::~QImage ()
       Destroys the image and cleans up.

bool QImage::allGray () const
       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.

       This function is slow for large 16-bit and 32-bit images.

       See also isGrayscale().

Endian QImage::bitOrder () const
       Returns the bit order for the image.

       If it is a 1-bpp image, this function returns either QImage::BigEndian or
       QImage::LittleEndian.

       If it is not a 1-bpp image, this function returns QImage::IgnoreEndian.

       See also depth().

uchar * QImage::bits () const
       Returns a pointer to the first pixel data. This is equivalent to scanLine(0).

       See also numBytes(), scanLine(), and jumpTable().

       Example: opengl/texture/gltexobj.cpp.

int QImage::bytesPerLine () const
       Returns the number of bytes per image scanline. This is equivalent to numBytes()/height().

       See also numBytes() and scanLine().

QRgb QImage::color ( int i ) const
       Returns the color in the color table at index i. The first color is at index 0.

       A color value is an RGB triplet. Use the qRed(), qGreen() and qBlue() functions (defined
       in qcolor.h) to get the color value components.

       See also setColor(), numColors(), and QColor.

       Example: themes/wood.cpp.

QRgb * QImage::colorTable () const
       Returns a pointer to the color table.

       See also numColors().

QImage QImage::convertBitOrder ( Endian bitOrder ) const
       Converts the bit order of the image to bitOrder and returns the converted image. The
       original image is not changed.

       Returns *this if the bitOrder is equal to the image bit order, or a null image if this
       image cannot be converted.

       See also bitOrder(), systemBitOrder(), and isNull().

QImage QImage::convertDepth ( int depth, int conversion_flags ) const
       Converts the depth (bpp) of the image to depth and returns the converted image. The
       original image is not changed.

       The depth argument must be 1, 8, 16 or 32.

       Returns *this if depth is equal to the image depth, or a null image if this image cannot
       be converted.

       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 conversion_flags to specify how you'd prefer this to
       happen.

       See also Qt::ImageConversionFlags, depth(), and isNull().

QImage QImage::convertDepth ( int depth ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

QImage QImage::convertDepthWithPalette ( int d, QRgb * palette, int palette_count, int
       conversion_flags = 0 ) const
       Returns an image with depth d, using the palette_count colors pointed to by palette. If d
       is 1 or 8, the returned image will have its color table ordered the same as palette.

       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 conversion_flags to specify how you'd prefer this to
       happen.

       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.

       Currently inefficient for non-32-bit images.

       See also Qt::ImageConversionFlags.

QImage QImage::copy () const
       Returns a deep copy of the image.

       See also detach().

QImage QImage::copy ( int x, int y, int w, int h, int conversion_flags = 0 ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns a deep copy of a sub-area of the image.

       The returned image is always w by h pixels in size, and is copied from position x, y in
       this image. In areas beyond this image pixels are filled with pixel 0.

       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 conversion_flags to specify how you'd prefer this to
       happen.

       See also bitBlt() and Qt::ImageConversionFlags.

QImage QImage::copy ( const QRect & r ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns a deep copy of a sub-area of the image.

       The returned image always has the size of the rectangle r. In areas beyond this image
       pixels are filled with pixel 0.

bool QImage::create ( int width, int height, int depth, int numColors = 0, Endian bitOrder =
       IgnoreEndian )
       Sets the image width, height, depth, its number of colors (in numColors), and bit order.
       Returns TRUE if successful, or FALSE if the parameters are incorrect or if memory cannot
       be allocated.

       The width and height is limited to 32767. depth must be 1, 8, 16 or 32. If depth is 1,
       bitOrder must be set to either QImage::LittleEndian or QImage::BigEndian. For other depths
       bitOrder must be QImage::IgnoreEndian.

       This function allocates a color table and a buffer for the image data. The image data is
       not initialized.

       The image buffer is allocated as a single block that consists of a table of scanline
       pointers (jumpTable()) and the image data (bits()).

       See also fill(), width(), height(), depth(), numColors(), bitOrder(), jumpTable(),
       scanLine(), bits(), bytesPerLine(), and numBytes().

bool QImage::create ( const QSize &, int depth, int numColors = 0, Endian bitOrder = IgnoreEndian
       )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

QImage QImage::createAlphaMask ( int conversion_flags = 0 ) const
       Builds and returns a 1-bpp mask from the alpha buffer in this image. Returns a null image
       if alpha buffer mode is disabled.

       See QPixmap::convertFromImage() for a description of the conversion_flags argument.

       The returned image has little-endian bit order, which you can convert to big-endianness
       using convertBitOrder().

       See also createHeuristicMask(), hasAlphaBuffer(), and setAlphaBuffer().

QImage QImage::createHeuristicMask ( bool clipTight = TRUE ) const
       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.

       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.

       The returned image has little-endian bit order, which you can convert to big-endianness
       using convertBitOrder().

       If clipTight is TRUE the mask is just large enough to cover the pixels; otherwise, the
       mask is larger than the data pixels.

       This function disregards the alpha buffer.

       See also createAlphaMask().

int QImage::depth () const
       Returns the depth of the image.

       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.

       The supported depths are 1, 8, 16 and 32.

       See also convertDepth().

void QImage::detach ()
       Detaches from shared image data and makes sure that this image is the only one referring
       to the data.

       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.

       See also copy().

       Example: themes/wood.cpp.

int QImage::dotsPerMeterX () const
       Returns the number of pixels that fit horizontally in a physical meter. This and
       dotsPerMeterY() define the intended scale and aspect ratio of the image.

       See also setDotsPerMeterX().

int QImage::dotsPerMeterY () const
       Returns the number of pixels that fit vertically in a physical meter. This and
       dotsPerMeterX() define the intended scale and aspect ratio of the image.

       See also setDotsPerMeterY().

void QImage::fill ( uint pixel )
       Fills the entire image with the pixel value pixel.

       If the depth of this image is 1, only the lowest bit is used. If you say fill(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.

       If the depth is 32 and the image has no alpha buffer, the pixel 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.

       Note: QImage::pixel() returns the color of the pixel at the given coordinates;
       QColor::pixel() 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 QColor::rgb() to use a specific color.

       See also invertPixels(), depth(), hasAlphaBuffer(), and create().

QImage QImage::fromMimeSource ( const QString & abs_name ) [static]
       Convenience function. Gets the data associated with the absolute name abs_name from the
       default mime source factory and decodes it to an image.

       See also QMimeSourceFactory, QImage::fromMimeSource(), and QImageDrag::decode().

bool QImage::hasAlphaBuffer () const
       Returns TRUE if alpha buffer mode is enabled; otherwise returns FALSE.

       See also setAlphaBuffer().

int QImage::height () const
       Returns the height of the image.

       See also width(), size(), and rect().

       Examples:

const char * QImage::imageFormat ( const QString & fileName ) [static]
       Returns a string that specifies the image format of the file fileName, or 0 if the file
       cannot be read or if the format is not recognized.

       The QImageIO documentation lists the guaranteed supported image formats, or use
       QImage::inputFormats() and QImage::outputFormats() to get lists that include the installed
       formats.

       See also load() and save().

QStringList QImage::inputFormatList () [static]
       Returns a list of image formats that are supported for image input.

       Note that if you want to iterate over the list, you should iterate over a copy, e.g.

	   QStringList list = myImage.inputFormatList();
	   QStringList::Iterator it = list.begin();
	   while( it != list.end() ) {
	       myProcessing( *it );
	       ++it;
	   }

       See also outputFormatList(), inputFormats(), and QImageIO.

       Example: showimg/showimg.cpp.

QStrList QImage::inputFormats () [static]
       Returns a list of image formats that are supported for image input.

       See also outputFormats(), inputFormatList(), and QImageIO.

void QImage::invertPixels ( bool invertAlpha = TRUE )
       Inverts all pixel values in the image.

       If the depth is 32: if invertAlpha is TRUE, the alpha bits are also inverted, otherwise
       they are left unchanged.

       If the depth is not 32, the argument invertAlpha has no meaning.

       Note that inverting an 8-bit image means to replace all pixels using color index i with a
       pixel using color index 255 minus i. Similarly for a 1-bit image. The color table is not
       changed.

       See also fill(), depth(), and hasAlphaBuffer().

bool QImage::isGrayscale () const
       For 16-bit and 32-bit images, this function is equivalent to allGray().

       For 8-bpp images, this function returns TRUE if color(i) is QRgb(i,i,i) for all indices of
       the color table; otherwise returns FALSE.

       See also allGray() and depth().

bool QImage::isNull () const
       Returns TRUE if it is a null image; otherwise returns FALSE.

       A null image has all parameters set to zero and no allocated data.

       Example: showimg/showimg.cpp.

uchar ** QImage::jumpTable () const
       Returns a pointer to the scanline pointer table.

       This is the beginning of the data block for the image.

       See also bits() and scanLine().

bool QImage::load ( const QString & fileName, const char * format = 0 )
       Loads an image from the file fileName. Returns TRUE if the image was successfully loaded;
       otherwise returns FALSE.

       If format is specified, the loader attempts to read the image using the specified format.
       If format is not specified (which is the default), the loader reads a few bytes from the
       header to guess the file format.

       The QImageIO documentation lists the supported image formats and explains how to add extra
       formats.

       See also loadFromData(), save(), imageFormat(), QPixmap::load(), and QImageIO.

bool QImage::loadFromData ( const uchar * buf, uint len, const char * format = 0 )
       Loads an image from the first len bytes of binary data in buf. Returns TRUE if the image
       was successfully loaded; otherwise returns FALSE.

       If format is specified, the loader attempts to read the image using the specified format.
       If format is not specified (which is the default), the loader reads a few bytes from the
       header to guess the file format.

       The QImageIO documentation lists the supported image formats and explains how to add extra
       formats.

       See also load(), save(), imageFormat(), QPixmap::loadFromData(), and QImageIO.

bool QImage::loadFromData ( QByteArray buf, const char * format = 0 )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Loads an image from the QByteArray buf.

QImage QImage::mirror () const
       Returns a QImage which is a vertically mirrored copy of this image. The original QImage is
       not changed.

QImage QImage::mirror ( bool horizontal, bool vertical ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns a mirror of the image, mirrored in the horizontal and/or the vertical direction
       depending on whether horizontal and vertical are set to TRUE or FALSE. The original image
       is not changed.

       See also smoothScale().

int QImage::numBytes () const
       Returns the number of bytes occupied by the image data.

       See also bytesPerLine() and bits().

int QImage::numColors () const
       Returns the size of the color table for the image.

       Notice that numColors() returns 0 for 16-bpp and 32-bpp images because these images do not
       use color tables, but instead encode pixel values as RGB triplets.

       See also setNumColors() and colorTable().

       Example: themes/wood.cpp.

QPoint QImage::offset () const
       Returns the number of pixels by which the image is intended to be offset by when
       positioning relative to other images.

bool QImage::operator!= ( const QImage & i ) const
       Returns TRUE if this image and image i 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.

       See also operator=().

QImage &; QImage::operator= ( const QImage & image )
       Assigns a shallow copy of image to this image and returns a reference to this image.

       See also copy().

QImage &; QImage::operator= ( const QPixmap & pixmap )
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Sets the image bits to the pixmap contents and returns a reference to the image.

       If the image shares data with other images, it will first dereference the shared data.

       Makes a call to QPixmap::convertToImage().

bool QImage::operator== ( const QImage & i ) const
       Returns TRUE if this image and image i 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.

       See also operator=().

QStringList QImage::outputFormatList () [static]
       Returns a list of image formats that are supported for image output.

       Note that if you want to iterate over the list, you should iterate over a copy, e.g.

	   QStringList list = myImage.outputFormatList();
	   QStringList::Iterator it = list.begin();
	   while( it != list.end() ) {
	       myProcessing( *it );
	       ++it;
	   }

       See also inputFormatList(), outputFormats(), and QImageIO.

QStrList QImage::outputFormats () [static]
       Returns a list of image formats that are supported for image output.

       See also inputFormats(), outputFormatList(), and QImageIO.

       Example: showimg/showimg.cpp.

QRgb QImage::pixel ( int x, int y ) const
       Returns the color of the pixel at the coordinates (x, y).

       If (x, y) is not on the image, the results are undefined.

       See also setPixel(), qRed(), qGreen(), qBlue(), and valid().

       Examples:

int QImage::pixelIndex ( int x, int y ) const
       Returns the pixel index at the given coordinates.

       If (x, y) is not valid, or if the image is not a paletted image (depth() > 8), the results
       are undefined.

       See also valid() and depth().

QRect QImage::rect () const
       Returns the enclosing rectangle (0, 0, width(), height()) of the image.

       See also width(), height(), and size().

void QImage::reset ()
       Resets all image parameters and deallocates the image data.

bool QImage::save ( const QString & fileName, const char * format, int quality = -1 ) const
       Saves the image to the file fileName, using the image file format format and a quality
       factor of quality. quality 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.

       Returns TRUE if the image was successfully saved; otherwise returns FALSE.

       See also load(), loadFromData(), imageFormat(), QPixmap::save(), and QImageIO.

QImage QImage::scale ( int w, int h, ScaleMode mode = ScaleFree ) const
       Returns a copy of the image scaled to a rectangle of width w and height h according to the
       ScaleMode mode.

       If mode is ScaleFree, the image is scaled to (w, h).

       If mode is ScaleMin, the image is scaled to a rectangle as large as possible inside (w,
       h), preserving the aspect ratio.

       If mode is ScaleMax, the image is scaled to a rectangle as small as possible outside (w,
       h), preserving the aspect ratio.

       If either the width w or the height h is 0 or negative, this function returns a null
       image.

       This function uses a simple, fast algorithm. If you need better quality, use smoothScale()
       instead.

       See also scaleWidth(), scaleHeight(), smoothScale(), and xForm().

QImage QImage::scale ( const QSize & s, ScaleMode mode = ScaleFree ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       The requested size of the image is s.

QImage QImage::scaleHeight ( int h ) const
       Returns a scaled copy of the image. The returned image has a height of h pixels. This
       function automatically calculates the width of the image so that the ratio of the image is
       preserved.

       If h is 0 or negative a null image is returned.

       See also scale(), scaleWidth(), smoothScale(), and xForm().

       Example: table/small-table-demo/main.cpp.

QImage QImage::scaleWidth ( int w ) const
       Returns a scaled copy of the image. The returned image has a width of w pixels. This
       function automatically calculates the height of the image so that the ratio of the image
       is preserved.

       If w is 0 or negative a null image is returned.

       See also scale(), scaleHeight(), smoothScale(), and xForm().

uchar * QImage::scanLine ( int i ) const
       Returns a pointer to the pixel data at the scanline with index i. The first scanline is at
       index 0.

       The scanline data is aligned on a 32-bit boundary.

       Warning: If you are accessing 32-bpp image data, cast the returned pointer to QRgb* (QRgb
       has a 32-bit size) and use it to read/write the pixel value. You cannot use the uchar*
       pointer directly, because the pixel format depends on the byte order on the underlying
       platform. Hint: use qRed(), qGreen() and qBlue(), etc. (qcolor.h) to access the pixels.

       Warning: If you are accessing 16-bpp image data, you must handle endianness yourself.

       See also bytesPerLine(), bits(), and jumpTable().

       Example: desktop/desktop.cpp.

void QImage::setAlphaBuffer ( bool enable )
       Enables alpha buffer mode if enable is TRUE, otherwise disables it. The default setting is
       disabled.

       An 8-bpp image has 8-bit pixels. A pixel is an index into the color table, which contains
       32-bit color values. In a 32-bpp image, the 32-bit pixels are the color values.

       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.

       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.

       The alpha buffer is used to set a mask when a QImage is translated to a QPixmap.

       See also hasAlphaBuffer() and createAlphaMask().

void QImage::setColor ( int i, QRgb c )
       Sets a color in the color table at index i to c.

       A color value is an RGB triplet. Use the qRgb() function (defined in qcolor.h) to make RGB
       triplets.

       See also color(), setNumColors(), and numColors().

       Examples:

void QImage::setDotsPerMeterX ( int x )
       Sets the value returned by dotsPerMeterX() to x.

void QImage::setDotsPerMeterY ( int y )
       Sets the value returned by dotsPerMeterY() to y.

void QImage::setNumColors ( int numColors )
       Resizes the color table to numColors colors.

       If the color table is expanded all the extra colors will be set to black (RGB 0,0,0).

       See also numColors(), color(), setColor(), and colorTable().

void QImage::setOffset ( const QPoint & p )
       Sets the value returned by offset() to p.

void QImage::setPixel ( int x, int y, uint index_or_rgb )
       Sets the pixel index or color at the coordinates (x, y) to index_or_rgb.

       If (x, y) is not valid, the result is undefined.

       If the image is a paletted image (depth() <= 8) and index_or_rgb >= numColors(), the
       result is undefined.

       See also pixelIndex(), pixel(), qRgb(), qRgba(), and valid().

void QImage::setText ( const char * key, const char * lang, const QString & s )
       Records string s for the keyword key. The key should be a portable keyword recognizable by
       other software - some suggested values can be found in the PNG specification. s can be any
       text. lang should specify the language code (see RFC 1766) or 0.

QSize QImage::size () const
       Returns the size of the image, i.e. its width and height.

       See also width(), height(), and rect().

QImage QImage::smoothScale ( int w, int h, ScaleMode mode = ScaleFree ) const
       Returns a smoothly scaled copy of the image. The returned image has a size of width w by
       height h pixels if mode is ScaleFree. The modes ScaleMin and ScaleMax may be used to
       preserve the ratio of the image: if mode is ScaleMin, the returned image is guaranteed to
       fit into the rectangle specified by w and h (it is as large as possible within the
       constraints); if mode is ScaleMax, the returned image fits at least into the specified
       rectangle (it is a small as possible within the constraints).

       For 32-bpp images and 1-bpp/8-bpp color images the result will be 32-bpp, whereas all-gray
       images (including black-and-white 1-bpp) will produce 8-bit grayscale images with the
       palette spanning 256 grays from black to white.

       This function uses code based on pnmscale.c by Jef Poskanzer.

       pnmscale.c - read a portable anymap and scale it

       Copyright (C) 1989, 1991 by Jef Poskanzer.

       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.

       See also scale() and mirror().

QImage QImage::smoothScale ( const QSize & s, ScaleMode mode = ScaleFree ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       The requested size of the image is s.

QImage QImage::swapRGB () const
       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.

Endian QImage::systemBitOrder () [static]
       Determines the bit order of the display hardware. Returns QImage::LittleEndian (LSB first)
       or QImage::BigEndian (MSB first).

       See also systemByteOrder().

Endian QImage::systemByteOrder () [static]
       Determines the host computer byte order. Returns QImage::LittleEndian (LSB first) or
       QImage::BigEndian (MSB first).

       See also systemBitOrder().

QString QImage::text ( const char * key, const char * lang = 0 ) const
       Returns the string recorded for the keyword key in language lang, or in a default language
       if lang is 0.

QString QImage::text ( const QImageTextKeyLang & kl ) const
       This is an overloaded member function, provided for convenience. It behaves essentially
       like the above function.

       Returns the string recorded for the keyword and language kl.

QStringList QImage::textKeys () const
       Returns the keywords for which some texts are recorded.

       Note that if you want to iterate over the list, you should iterate over a copy, e.g.

	   QStringList list = myImage.textKeys();
	   QStringList::Iterator it = list.begin();
	   while( it != list.end() ) {
	       myProcessing( *it );
	       ++it;
	   }

       See also textList(), text(), setText(), and textLanguages().

QStringList QImage::textLanguages () const
       Returns the language identifiers for which some texts are recorded.

       Note that if you want to iterate over the list, you should iterate over a copy, e.g.

	   QStringList list = myImage.textLanguages();
	   QStringList::Iterator it = list.begin();
	   while( it != list.end() ) {
	       myProcessing( *it );
	       ++it;
	   }

       See also textList(), text(), setText(), and textKeys().

QValueList<;QImageTextKeyLang> QImage::textList () const
       Returns a list of QImageTextKeyLang objects that enumerate all the texts key/language
       pairs set by setText() for this image.

       Note that if you want to iterate over the list, you should iterate over a copy, e.g.

	   QValueList<QImageTextKeyLang> list = myImage.textList();
	   QValueList<QImageTextKeyLang>::Iterator it = list.begin();
	   while( it != list.end() ) {
	       myProcessing( *it );
	       ++it;
	   }

bool QImage::valid ( int x, int y ) const
       Returns TRUE if ( x, y ) is a valid coordinate in the image; otherwise returns FALSE.

       See also width(), height(), and pixelIndex().

       Examples:

int QImage::width () const
       Returns the width of the image.

       See also height(), size(), and rect().

       Examples:

QImage QImage::xForm ( const QWMatrix & matrix ) const
       Returns a copy of the image that is transformed using the transformation matrix, matrix.

       The transformation matrix is internally adjusted to compensate for unwanted translation,
       i.e. xForm() returns the smallest image that contains all the transformed points of the
       original image.

       See also scale(), QPixmap::xForm(), QPixmap::trueMatrix(), and QWMatrix.

RELATED FUNCTION DOCUMENTATION
QDataStream &; operator<< ( QDataStream & s, const QImage & image )
       Writes the image image to the stream s as a PNG image.

       See also QImage::save() and Format of the QDataStream operators.

QDataStream &; operator>> ( QDataStream & s, QImage & image )
       Reads an image from the stream s and stores it in image.

       See also QImage::load() and Format of the QDataStream operators.

SEE ALSO
       http://doc.trolltech.com/qimage.html http://www.trolltech.com/faq/tech.html

COPYRIGHT
       Copyright 1992-2001 Trolltech AS, http://www.trolltech.com.  See the license file included
       in the distribution for a complete license statement.

AUTHOR
       Generated automatically from the source code.

BUGS
       If you find a bug in Qt, please report it as described in
       http://doc.trolltech.com/bughowto.html.	Good bug reports help us to help you. Thank you.

       The definitive Qt documentation is provided in HTML format; it is located at
       $QTDIR/doc/html and can be read using Qt Assistant or with a web browser. This man page is
       provided as a convenience for those users who prefer man pages, although this format is
       not officially supported by Trolltech.

       If you find errors in this manual page, please report them to qt-bugs@trolltech.com.
       Please include the name of the manual page (qimage.3qt) and the Qt version (3.1.1).

Trolltech AS				 9 December 2002			      QImage(3qt)


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