QImage(3qt)QImage(3qt)NAME
QImage - Hardware-independent pixmap representation with
direct access to the pixel data
#include <qimage.h>
Public Members
enum Endian { IgnoreEndian, BigEndian, LittleEndian }
QImage ()
QImage ( int width, int height, int depth, int
numColors=0, Endian bitOrder=IgnoreEndian )
QImage ( const QSize &, int depth, int numColors=0, Endian
bitOrder=IgnoreEndian )
QImage ( const QString & fileName, const char * format=0 )
QImage ( const char * xpm[] )
QImage ( const QByteArray & data )
QImage ( uchar * data, int w, int h, int depth, QRgb *
colortable, int numColors, Endian bitOrder )
QImage ( const QImage & )
~QImage ()
QImage& operator= ( const QImage & )
QImage& operator= ( const QPixmap & )
bool operator== ( const QImage & ) const
bool operator!= ( const QImage & ) const
void detach ()
QImage copy () const
QImage copy ( int x, int y, int w, int h, int
conversion_flags=0 ) const
QImage copy ( QRect & ) const
QImage copy ( const QRect & ) 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 )
bool hasAlphaBuffer () const
void setAlphaBuffer ( bool )
bool allGray () const
bool isGrayscale () const
uchar* bits () const
uchar* scanLine ( int ) 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 )
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QImage(3qt)QImage(3qt)
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 ) const
QImage convertDepthWithPalette ( int, QRgb * p, int pc,
int cf=0 ) const
QImage convertDepth ( int, int conversion_flags ) const
QImage convertBitOrder ( Endian ) const
QImage smoothScale ( int width, int height ) const
QImage createAlphaMask ( int conversion_flags=0 ) const
QImage createHeuristicMask ( bool clipTight=TRUE ) const
QImage mirror () const
QImage mirror ( bool horizontally, bool vertically ) 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 data, const char * format=0
)
bool save ( const QString & fileName, const char * format
) const
bool save ( const QString & fileName, const char * format,
int quality ) 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 )
void setDotsPerMeterY ( int )
QPoint offset () const
void setOffset ( const QPoint & )
QValueList<QImageTextKeyLang> textList () const
QStringList textLanguages () const
QStringList textKeys () const
QString text ( const char * key, const char * lang=0 )
const
QString text ( const QImageTextKeyLang & ) const
void setText ( const char * key, const char * lang, const
QString & )
Static Public Members
Endian systemBitOrder ()
Endian systemByteOrder ()
const char* imageFormat ( const QString & fileName )
QStrList inputFormats ()
QStrList outputFormats ()
QStringList inputFormatList ()
QStringList outputFormatList ()
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QImage(3qt)QImage(3qt)RELATED FUNCTION DOCUMENTATION
(Note that these are not member functions.)
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
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 maximum
2 colors. There are two different formats; big endian (MSB
first) or little endian (LSB first) bit order. To access a
single bit, you will have to do some bitshifts:
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
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QImage(3qt)QImage(3qt)
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
and 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);
The scanlines are 32-bit aligned for all depths.
The QImage class uses explicit sharing, similar to that of
QArray.
See also QImageIO, QPixmap and Shared Classes
Examples: qtimage/qtimage.cpp qmag/qmag.cpp
desktop/desktop.cpp
Member Type Documentation
QImage::Endian
This enum type is used to describe the endianness of the
CPU and graphics hardware.
The current values are:
IgnoreEndian - does not matter. Useful for some operations
that are independent of endianness
BigEndian - network byte order, like on SPARC and Motorola
CPUs.
LittleEndian - PC/Alpha byte order.
MEMBER FUNCTION DOCUMENTATIONQImage::QImage ()
Constructs a null image.
See also isNull().
QImage::QImage ( const QByteArray & array )
Constructs an image from array, which must be in a
supported image format image.
See also loadFromData().
QImage::QImage ( const QSize & size, int depth, int numColors=0,
Endian bitOrder=IgnoreEndian )
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QImage(3qt)QImage(3qt)
Constructs an image with size size pixels, depth depth
bits, numColors and bitOrder endianness.
QImage::QImage ( const QString & fileName, const char * format=0
)
Constructs an image from loading fileName and an optional
format.
See also load().
QImage::QImage ( const QImage & image )
Constructs a shallow copy of image.
QImage::QImage ( const char * 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.
In order to use that sort of declaration, you must cast
the variable back to <nobr>const char **</nobr> when you
create the QImage.
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 ( uchar * yourdata, int w, int h, int depth, 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 will not delete the buffer at destruction.
If colortable is 0, a color table sufficient for numColors
will be allocated (and destructed later).
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QImage(3qt)QImage(3qt)QImage::~QImage ()
Destructs the image and cleans up.
bool QImage::allGray () const
Returns TRUE if all the colors in the image are shades of
gray, that is their R, G, and B components are equal. This
function is slow for large 16-bit and 32-bit images.
QImage::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. Equivalent to
scanLine(0).
See also scanLine().
int QImage::bytesPerLine () const
Returns the number of bytes per image scanline. This is
equivalent to numBytes()/height().
QRgb QImage::color ( int i ) const
Returns the color in the color table at index i.
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() and QColor.
QRgb * QImage::colorTable () const
Returns a pointer to the color table.
QImage QImage::convertBitOrder ( Endian bitOrder ) const
Converts the bit order of the image to bitOrder and
returns the converted image.
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() and systemBitOrder().
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 left
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undisturbed.
The depth argument must be 1, 8, 16 or 32.
See QPixmap::convertFromImage for a description of the
conversion_flags argument.
Returns *this if depth is equal to the image depth, or a
null image if this image cannot be converted.
See also depth() and isNull().
QImage QImage::convertDepth ( int depth ) const
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
QImage QImage::convertDepthWithPalette ( int d, QRgb * palette,
int palette_count, int conversion_flags=0 ) const
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, as it may change in future implementations.
Currently inefficient for non 32-bit images.
QImage QImage::copy () const
Returns a deep copy of the image.
QImage QImage::copy ( int x, int y, int w, int h, int
conversion_flags=0 ) const
Returns a deep copy of a sub-area of the image.
The returned image is always w by h pixels is size. If the
area is beyond this image, the pixels are filled with
pixel 0.
See also bitBlt().
QImage QImage::copy ( const QRect & r ) const
This is an overloaded member function, provided for
convenience. It differs from the above function only in
what argument(s) it accepts.
bool QImage::create ( int width, int height, int depth, int
numColors=0, Endian bitOrder=IgnoreEndian )
Sets the image width, height, depth, number of colors 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 or 32. If depth is 1, then bitOrder must be set to
either QImage::LittleEndian or QImage::BigEndian. For
other depths, bitOrder must be QImage::IgnoreEndian.
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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 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 differs from the above function only in
what argument(s) it accepts.
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().
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 over 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 voting
results are undocumented.
The returned image has little-endian bit order, which you
can convert to big-endianness using convertBitOrder().
This function disregards the alpha buffer.
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.
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QImage(3qt)QImage(3qt)void QImage::detach ()
Detaches from shared image data and makes sure that this
image is the only one referring 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.
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.
bool QImage::hasAlphaBuffer () const
Returns TRUE if alpha buffer mode is enabled, otherwise
FALSE.
See also setAlphaBuffer().
int QImage::height () const
Returns the height of the image.
See also width(), size() and rect().
const char* QImage::imageFormat ( const QString & fileName )
[static]
Returns a string that specifies the image format of the
file fileName, or null if the file cannot be read or if
the format cannot be recognized.
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QImage(3qt)QImage(3qt)
The QImageIO documentation lists the guaranteed supported
image formats, or use the QImage::inputFormats()QImage::outputFormats() to get lists that include
installed formats.
See also load() and save().
QStringList QImage::inputFormatList () [static]
Returns a list of image formats which are supported for
image input.
QStrList QImage::inputFormats () [static]
Returns a list of image formats which are supported for
image input.
See also inputFormatList().
void QImage::invertPixels ( bool invertAlpha = TRUE )
Inverts all pixel values in the image.
For 32 bit (24 RGB + alpha buffer) images, set invertAlpha
to FALSE if you want the alpha bits to be unchanged,
otherwise they are inverted too.
bool QImage::isGrayscale () const
Returns TRUE if the image is allGray(), and if the image
is 32-bpp or a 256-color 8-bpp image for which color(i) is
QRgb(i,i,i).
bool QImage::isNull () const
Returns TRUE if it is a null image.
A null image has all parameters set to zero and no
allocated data.
Examples: qtimage/qtimage.cpp
uchar ** QImage::jumpTable () const
Returns a pointer to the scanline pointer table.
This is the beginning of the data block for the image.
bool QImage::load ( const QString & fileName, const char *
format=0 )
Loads an image from the file fileName. Returns TRUE if
successful, or FALSE if the image could not be loaded.
If format is specified, the loader attempts to read the
image using the specified format. If format is not
specified (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.
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QImage(3qt)QImage(3qt)
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 binary data in buf (len bytes).
Returns TRUE if successful, or FALSE if the image could
not be loaded.
If format is specified, the loader attempts to read the
image using the specified format. If format is not
specified (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 differs from the above function only in
what argument(s) it accepts.
Loads from a QByteArray.
QImage QImage::mirror () const
Returns a QImage which is a vertically mirrored copy of
this image. The original QImage is left unchanged.
QImage QImage::mirror ( bool horizontal, bool vertical ) const
Returns the image mirrored in the horizontal and/or
vertical direction.
See also smoothScale().
int QImage::numBytes () const
Returns the number of bytes occupied by the image data.
See also bytesPerLine().
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, since these images do not use color tables, but
instead encode pixel values as RGB triplets.
QPoint QImage::offset () const
Returns the number of pixels by which the image is
intended to by offset by when positioning relative to
other images.
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QImage(3qt)QImage(3qt)bool QImage::operator!= ( const QImage & i ) const
Returns TRUE if this image and i have different contents,
and FALSE if they they have the same. This can be slow. Of
course, this function returns quickly if e.g. the two
images' widths are different.
See also operator=().
QImage & QImage::operator= ( const QPixmap & pixmap )
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().
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().
bool QImage::operator== ( const QImage & i ) const
Returns TRUE if this image and i have the same contents,
and FALSE if they differ. This can be slow. Of course,
this function returns quickly if e.g. the two images'
widths are different.
See also operator=().
QStringList QImage::outputFormatList () [static]
Returns a list of image formats which are supported for
image output.
QStrList QImage::outputFormats () [static]
Returns a list of image formats which are supported for
image output.
See also QImage::outputFormatList().
QRgb QImage::pixel ( int x, int y ) const
Returns the actual color of the pixel at the given
coordinates.
If (x,y) is not on the image, the results are undefined.
See also setPixel(), qRed(), qGreen() and qBlue().
Examples: qmag/qmag.cpp
int QImage::pixelIndex ( int x, int y ) const
Returns the pixel index at the given coordinates.
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If (x,y) is not valid, or if the image is not a paletted
image (depth() > 8), the results are undefined.
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.
Examples: qtimage/qtimage.cpp
bool QImage::save ( const QString & fileName, const char * format
) const
Saves the image to the file fileName, using the image file
format format and default quality settings. Returns TRUE
if successful, or FALSE if the image could not be saved.
See also load(), loadFromData(), imageFormat(),
QPixmap::save() and QImageIO.
bool QImage::save ( const QString & fileName, const char *
format, int quality ) const
Saves the image to the file fileName, using the image file
format format and a quality factor 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
to use the default settings. Returns TRUE if successful,
or FALSE if the image could not be saved.
See also load(), loadFromData(), imageFormat(),
QPixmap::save() and QImageIO.
uchar * QImage::scanLine ( int i ) const
Returns a pointer to the pixel data at the i'th scanline.
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() and friends (qcolor.h) to access the pixels.
Warning: If you are accessing 16-bpp image data, you have
to handle endianness yourself for now.
See also bits().
Examples: desktop/desktop.cpp
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QImage(3qt)QImage(3qt)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().
Examples: desktop/desktop.cpp
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, then all new colors will
be set to black (RGB 0,0,0).
See also color() and setColor().
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 given coordinates.
If (x,y) is not valid, or if the image is a paletted image
(depth() <= 8) and index_or_rgb >= numColors(), the
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QImage(3qt)QImage(3qt)
results are undefined.
See also qRgb() and qRgba().
void QImage::setText ( const char * key, const char * lang, const
QString & s )
Records 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.
Note that no QImageIO handlers currently read or write
this data. In an upcoming Qt version, PNG I/O will do so.
QSize QImage::size () const
Returns the size of the image.
See also width(), height() and rect().
QImage QImage::smoothScale ( int width, int height ) const
Returns a copy of the image smoothly scaled to width by
height pixels. For 32-bpp images, and 1-bpp/8-bpp color
images, the result will be 32-bpp, while 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 mirror().
QImage QImage::swapRGB () const
Returns a QImage where the values of the red and blue
components of all pixels have been swapped, effectively
converting a RGB image to a BGR image. The original QImage
is left unchanged.
QImage::Endian QImage::systemBitOrder() [static]
Determines the bit order of the display hardware. Returns
QImage::LittleEndian (LSB first) or QImage::BigEndian (MSB
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QImage(3qt)QImage(3qt)
first).
QImage::Endian QImage::systemByteOrder() [static]
Determines the host computer byte order. Returns
QImage::LittleEndian (LSB first) or QImage::BigEndian (MSB
first).
QString QImage::text ( const QImageTextKeyLang & kl ) const
Returns the string recorded for the keyword and language
kl, or in a default language if lang is 0.
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.
QStringList QImage::textKeys () const
Returns the keywords for which some texts are recorded.
See also textList(), text(), setText() and
textLanguages().
QStringList QImage::textLanguages () const
Returns the language identifiers for which some texts are
recorded.
See also textList(), text(), setText() and textKeys().
QValueList<;QImageTextKeyLang> QImage::textList () const
Returns a list of QImageTextKeyLang objects which
enumerate all the texts key/languaage pairs set by
setText() for this image.
bool QImage::valid ( int x, int y ) const
Tests if the ( x, y ) is a valid coordinate in the image.
Examples: qmag/qmag.cpp
int QImage::width () const
Returns the width of the image.
See also height(), size() and rect().
RELATED FUNCTION DOCUMENTATIONQDataStream & operator<;< (QDataStream & s, const QImage & image)
Writes an image to the stream 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.
See also QImage::load() and Format of the QDataStream
Trolltech AS 13 June 2001 16
QImage(3qt)QImage(3qt)
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
make our job much simpler. Thank you.
In case of content or formattting problems with 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 (2.3.1).
Trolltech AS 13 June 2001 17
