class QImage¶

The QImage class provides a hardware-independent image representation that allows direct access to the pixel data, and can be used as a paint device. More…

Synopsis¶

Methods¶

def __init__()
def allGray()
def applyColorTransform()
def bitPlaneCount()
def bytesPerLine()
def cacheKey()
def color()
def colorSpace()
def colorTable()
def colorTransformed()
def constBits()
def constScanLine()
def convertTo()
def convertToColorSpace()
def convertToFormat()
def convertToFormat_helper()
def convertToFormat_inplace()
def convertedTo()
def convertedToColorSpace()
def copy()
def createAlphaMask()
def createHeuristicMask()
def createMaskFromColor()
def detachMetadata()
def deviceIndependentSize()
def dotsPerMeterX()
def dotsPerMeterY()
def fill()
def format()
def hasAlphaChannel()
def invertPixels()
def isGrayscale()
def isNull()
def load()
def loadFromData()
def mirror()
def mirrored()
def mirrored_helper()
def mirrored_inplace()
def offset()
def __ne__()
def __eq__()
def pixel()
def pixelColor()
def pixelFormat()
def pixelIndex()
def rect()
def reinterpretAsFormat()
def rgbSwap()
def rgbSwapped()
def rgbSwapped_helper()
def rgbSwapped_inplace()
def save()
def scaled()
def scaledToHeight()
def scaledToWidth()
def setAlphaChannel()
def setColor()
def setColorCount()
def setColorSpace()
def setColorTable()
def setDevicePixelRatio()
def setDotsPerMeterX()
def setDotsPerMeterY()
def setOffset()
def setPixel()
def setPixelColor()
def setText()
def size()
def sizeInBytes()
def smoothScaled()
def swap()
def text()
def textKeys()
def transformed()
def valid()

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description¶

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

Qt provides four classes for handling image data: QImage , QPixmap , QBitmap and QPicture . QImage is designed and optimized for I/O, and for direct pixel access and manipulation, while QPixmap is designed and optimized for showing images on screen. QBitmap is only a convenience class that inherits QPixmap , ensuring a depth of 1. Finally, the QPicture class is a paint device that records and replays QPainter commands.

Because QImage is a QPaintDevice subclass, QPainter can be used to draw directly onto images. When using QPainter on a QImage , the painting can be performed in another thread than the current GUI thread.

The QImage class supports several image formats described by the Format enum. These include monochrome, 8-bit, 32-bit and alpha-blended images which are available in all versions of Qt 4.x.

QImage provides a collection of functions that can be used to obtain a variety of information about the image. There are also several functions that enables transformation of the image.

QImage objects can be passed around by value since the QImage class uses implicit data sharing. QImage objects can also be streamed and compared.

Note

If you would like to load QImage objects in a static build of Qt, refer to the Plugin HowTo.

Warning

Painting on a QImage with the format Format_Indexed8 or Format_CMYK8888 is not supported.

Reading and Writing Image Files¶

QImage provides several ways of loading an image file: The file can be loaded when constructing the QImage object, or by using the load() or loadFromData() functions later on. QImage also provides the static fromData() function, constructing a QImage from the given data. When loading an image, the file name can either refer to an actual file on disk or to one of the application’s embedded resources. See The Qt Resource System overview for details on how to embed images and other resource files in the application’s executable.

Simply call the save() function to save a QImage object.

The complete list of supported file formats are available through the supportedImageFormats() and supportedImageFormats() functions. New file formats can be added as plugins. By default, Qt supports the following formats:

Format

Description

Qt’s support

BMP

Windows Bitmap

Read/write

GIF

Graphic Interchange Format (optional)

Read

JPG

Joint Photographic Experts Group

Read/write

JPEG

Joint Photographic Experts Group

Read/write

PNG

Portable Network Graphics

Read/write

PBM

Portable Bitmap

Read

PGM

Portable Graymap

Read

PPM

Portable Pixmap

Read/write

XBM

X11 Bitmap

Read/write

XPM

X11 Pixmap

Read/write

Format	Description	Qt’s support
BMP	Windows Bitmap	Read/write
GIF	Graphic Interchange Format (optional)	Read
JPG	Joint Photographic Experts Group	Read/write
JPEG	Joint Photographic Experts Group	Read/write
PNG	Portable Network Graphics	Read/write
PBM	Portable Bitmap	Read
PGM	Portable Graymap	Read
PPM	Portable Pixmap	Read/write
XBM	X11 Bitmap	Read/write
XPM	X11 Pixmap	Read/write

Image Information¶

QImage provides a collection of functions that can be used to obtain a variety of information about the image:

Available Functions

Geometry

The size() , width() , height() , dotsPerMeterX(), and dotsPerMeterY() functions provide information about the image size and aspect ratio.

The rect() function returns the image’s enclosing rectangle. The valid() function tells if a given pair of coordinates is within this rectangle. The offset() function returns the number of pixels by which the image is intended to be offset by when positioned relative to other images, which also can be manipulated using the setOffset() function.

Colors

The color of a pixel can be retrieved by passing its coordinates to the pixel() function. The pixel() function returns the color as a QRgb value independent of the image’s format.

In case of monochrome and 8-bit images, the colorCount() and colorTable() functions provide information about the color components used to store the image data: The colorTable() function returns the image’s entire color table. To obtain a single entry, use the pixelIndex() function to retrieve the pixel index for a given pair of coordinates, then use the color() function to retrieve the color. Note that if you create an 8-bit image manually, you have to set a valid color table on the image as well.

The hasAlphaChannel() function tells if the image’s format respects the alpha channel, or not. The allGray() and isGrayscale() functions tell whether an image’s colors are all shades of gray.

See also the Pixel Manipulation and Image Transformations sections.

Text

The text() function returns the image text associated with the given text key. An image’s text keys can be retrieved using the textKeys() function. Use the setText() function to alter an image’s text.

Low-level information

The depth() function returns the depth of the image. The supported depths are 1 (monochrome), 8, 16, 24 and 32 bits. The bitPlaneCount() function tells how many of those bits that are used. For more information see the Image Formats section.

The format(), bytesPerLine(), and sizeInBytes() functions provide low-level information about the data stored in the image.

The cacheKey() function returns a number that uniquely identifies the contents of this QImage object.

	Available Functions
Geometry	The `size()` , `width()` , `height()` , dotsPerMeterX(), and dotsPerMeterY() functions provide information about the image size and aspect ratio. The `rect()` function returns the image’s enclosing rectangle. The `valid()` function tells if a given pair of coordinates is within this rectangle. The `offset()` function returns the number of pixels by which the image is intended to be offset by when positioned relative to other images, which also can be manipulated using the `setOffset()` function.
Colors	The color of a pixel can be retrieved by passing its coordinates to the `pixel()` function. The `pixel()` function returns the color as a `QRgb` value independent of the image’s format. In case of monochrome and 8-bit images, the `colorCount()` and colorTable() functions provide information about the color components used to store the image data: The colorTable() function returns the image’s entire color table. To obtain a single entry, use the `pixelIndex()` function to retrieve the pixel index for a given pair of coordinates, then use the color() function to retrieve the color. Note that if you create an 8-bit image manually, you have to set a valid color table on the image as well. The hasAlphaChannel() function tells if the image’s format respects the alpha channel, or not. The allGray() and isGrayscale() functions tell whether an image’s colors are all shades of gray. See also the `Pixel Manipulation` and `Image Transformations` sections.
Text	The text() function returns the image text associated with the given text key. An image’s text keys can be retrieved using the textKeys() function. Use the `setText()` function to alter an image’s text.
Low-level information	The `depth()` function returns the depth of the image. The supported depths are 1 (monochrome), 8, 16, 24 and 32 bits. The bitPlaneCount() function tells how many of those bits that are used. For more information see the `Image Formats` section. The format(), bytesPerLine(), and sizeInBytes() functions provide low-level information about the data stored in the image. The cacheKey() function returns a number that uniquely identifies the contents of this `QImage` object.

Pixel Manipulation¶

The functions used to manipulate an image’s pixels depend on the image format. The reason is that monochrome and 8-bit images are index-based and use a color lookup table, while 32-bit images store ARGB values directly. For more information on image formats, see the Image Formats section.

In case of a 32-bit image, the setPixel() function can be used to alter the color of the pixel at the given coordinates to any other color specified as an ARGB quadruplet. To make a suitable QRgb value, use the qRgb() (adding a default alpha component to the given RGB values, i.e. creating an opaque color) or qRgba() function. For example:

32-bit
	image = QImage(3, 3, QImage.Format_RGB32) value = QRgb() value = qRgb(189, 149, 39) # 0xffbd9527 image.setPixel(1, 1, value) value = qRgb(122, 163, 39) # 0xff7aa327 image.setPixel(0, 1, value) image.setPixel(1, 0, value) value = qRgb(237, 187, 51) # 0xffedba31 image.setPixel(2, 1, value)

32-bit

qimage-32bit_scaled1

image = QImage(3, 3, QImage.Format_RGB32)
value = QRgb()
value = qRgb(189, 149, 39) # 0xffbd9527
image.setPixel(1, 1, value)
value = qRgb(122, 163, 39) # 0xff7aa327
image.setPixel(0, 1, value)
image.setPixel(1, 0, value)
value = qRgb(237, 187, 51) # 0xffedba31
image.setPixel(2, 1, value)

In case of a 8-bit and monchrome images, the pixel value is only an index from the image’s color table. So the setPixel() function can only be used to alter the color of the pixel at the given coordinates to a predefined color from the image’s color table, i.e. it can only change the pixel’s index value. To alter or add a color to an image’s color table, use the setColor() function.

An entry in the color table is an ARGB quadruplet encoded as an QRgb value. Use the qRgb() and qRgba() functions to make a suitable QRgb value for use with the setColor() function. For example:

8-bit
	image = QImage(3, 3, QImage.Format_Indexed8) value = QRgb() value = qRgb(122, 163, 39) # 0xff7aa327 image.setColor(0, value) value = qRgb(237, 187, 51) # 0xffedba31 image.setColor(1, value) value = qRgb(189, 149, 39) # 0xffbd9527 image.setColor(2, value) image.setPixel(0, 1, 0) image.setPixel(1, 0, 0) image.setPixel(1, 1, 2) image.setPixel(2, 1, 1)

8-bit

qimage-8bit_scaled2

image = QImage(3, 3, QImage.Format_Indexed8)
value = QRgb()
value = qRgb(122, 163, 39) # 0xff7aa327
image.setColor(0, value)
value = qRgb(237, 187, 51) # 0xffedba31
image.setColor(1, value)
value = qRgb(189, 149, 39) # 0xffbd9527
image.setColor(2, value)
image.setPixel(0, 1, 0)
image.setPixel(1, 0, 0)
image.setPixel(1, 1, 2)
image.setPixel(2, 1, 1)

For images with more than 8-bit per color-channel. The methods setPixelColor() and pixelColor() can be used to set and get with QColor values.

QImage also provide the scanLine() function which returns a pointer to the pixel data at the scanline with the given index, and the bits() function which returns a pointer to the first pixel data (this is equivalent to scanLine(0)).

Image Formats¶

Each pixel stored in a QImage is represented by an integer. The size of the integer varies depending on the format. QImage supports several image formats described by the Format enum.

Monochrome images are stored using 1-bit indexes into a color table with at most two colors. There are two different types of monochrome images: big endian (MSB first) or little endian (LSB first) bit order.

8-bit images are stored using 8-bit indexes into a color table, i.e. they have a single byte per pixel. The color table is a QList< QRgb >, and the QRgb typedef is equivalent to an unsigned int containing an ARGB quadruplet on the format 0xAARRGGBB.

32-bit images have no color table; instead, each pixel contains an QRgb value. There are three different types of 32-bit images storing RGB (i.e. 0xffRRGGBB), ARGB and premultiplied ARGB values respectively. In the premultiplied format the red, green, and blue channels are multiplied by the alpha component divided by 255.

An image’s format can be retrieved using the format() function. Use the convertToFormat() functions to convert an image into another format. The allGray() and isGrayscale() functions tell whether a color image can safely be converted to a grayscale image.

Image Transformations¶

QImage supports a number of functions for creating a new image that is a transformed version of the original: The createAlphaMask() function builds and returns a 1-bpp mask from the alpha buffer in this image, and the createHeuristicMask() function creates and returns a 1-bpp heuristic mask for this image. The latter function works by selecting a color from one of the corners, then chipping away pixels of that color starting at all the edges.

The mirrored() function returns a mirror of the image in the desired direction, the scaled() returns a copy of the image scaled to a rectangle of the desired measures, and the rgbSwapped() function constructs a BGR image from a RGB image.

The scaledToWidth() and scaledToHeight() functions return scaled copies of the image.

The transformed() function returns a copy of the image that is transformed with the given transformation matrix and transformation mode: Internally, the transformation matrix is adjusted to compensate for unwanted translation, i.e. transformed() returns the smallest image containing all transformed points of the original image. The static trueMatrix() function returns the actual matrix used for transforming the image.

There are also functions for changing attributes of an image in-place:

Function

Description

setDotsPerMeterX()

Defines the aspect ratio by setting the number of pixels that fit horizontally in a physical meter.

setDotsPerMeterY()

Defines the aspect ratio by setting the number of pixels that fit vertically in a physical meter.

fill()

Fills the entire image with the given pixel value.

invertPixels()

Inverts all pixel values in the image using the given InvertMode value.

setColorTable()

Sets the color table used to translate color indexes. Only monochrome and 8-bit formats.

setColorCount()

Resizes the color table. Only monochrome and 8-bit formats.

See also

QImageReader QImageWriter QPixmap QSvgRendererImage Composition ExampleScribble Example

Function	Description
setDotsPerMeterX()	Defines the aspect ratio by setting the number of pixels that fit horizontally in a physical meter.
setDotsPerMeterY()	Defines the aspect ratio by setting the number of pixels that fit vertically in a physical meter.
`fill()`	Fills the entire image with the given pixel value.
invertPixels()	Inverts all pixel values in the image using the given `InvertMode` value.
setColorTable()	Sets the color table used to translate color indexes. Only monochrome and 8-bit formats.
setColorCount()	Resizes the color table. Only monochrome and 8-bit formats.

class InvertMode¶

This enum type is used to describe how pixel values should be inverted in the invertPixels() function.

Constant

Description

QImage.InvertRgb

Invert only the RGB values and leave the alpha channel unchanged.

QImage.InvertRgba

Invert all channels, including the alpha channel.

See also

invertPixels()

Constant	Description
QImage.InvertRgb	Invert only the RGB values and leave the alpha channel unchanged.
QImage.InvertRgba	Invert all channels, including the alpha channel.

class Format¶

The following image formats are available in Qt. See the notes after the table.

Constant

Description

QImage.Format_Invalid

The image is invalid.

QImage.Format_Mono

The image is stored using 1-bit per pixel. Bytes are packed with the most significant bit (MSB) first.

QImage.Format_MonoLSB

The image is stored using 1-bit per pixel. Bytes are packed with the less significant bit (LSB) first.

QImage.Format_Indexed8

The image is stored using 8-bit indexes into a colormap.

QImage.Format_RGB32

The image is stored using a 32-bit RGB format (0xffRRGGBB).

QImage.Format_ARGB32

The image is stored using a 32-bit ARGB format (0xAARRGGBB).

QImage.Format_ARGB32_Premultiplied

The image is stored using a premultiplied 32-bit ARGB format (0xAARRGGBB), i.e. the red, green, and blue channels are multiplied by the alpha component divided by 255. (If RR, GG, or BB has a higher value than the alpha channel, the results are undefined.) Certain operations (such as image composition using alpha blending) are faster using premultiplied ARGB32 than with plain ARGB32.

QImage.Format_RGB16

The image is stored using a 16-bit RGB format (5-6-5).

QImage.Format_ARGB8565_Premultiplied

The image is stored using a premultiplied 24-bit ARGB format (8-5-6-5).

QImage.Format_RGB666

The image is stored using a 24-bit RGB format (6-6-6). The unused most significant bits is always zero.

QImage.Format_ARGB6666_Premultiplied

The image is stored using a premultiplied 24-bit ARGB format (6-6-6-6).

QImage.Format_RGB555

The image is stored using a 16-bit RGB format (5-5-5). The unused most significant bit is always zero.

QImage.Format_ARGB8555_Premultiplied

The image is stored using a premultiplied 24-bit ARGB format (8-5-5-5).

QImage.Format_RGB888

The image is stored using a 24-bit RGB format (8-8-8).

QImage.Format_RGB444

The image is stored using a 16-bit RGB format (4-4-4). The unused bits are always zero.

QImage.Format_ARGB4444_Premultiplied

The image is stored using a premultiplied 16-bit ARGB format (4-4-4-4).

QImage.Format_RGBX8888

The image is stored using a 32-bit byte-ordered RGB(x) format (8-8-8-8). This is the same as the Format_RGBA8888 except alpha must always be 255.

QImage.Format_RGBA8888

The image is stored using a 32-bit byte-ordered RGBA format (8-8-8-8). Unlike ARGB32 this is a byte-ordered format, which means the 32bit encoding differs between big endian and little endian architectures, being respectively (0xRRGGBBAA) and (0xAABBGGRR). The order of the colors is the same on any architecture if read as bytes 0xRR,0xGG,0xBB,0xAA.

QImage.Format_RGBA8888_Premultiplied

The image is stored using a premultiplied 32-bit byte-ordered RGBA format (8-8-8-8).

QImage.Format_BGR30

The image is stored using a 32-bit BGR format (x-10-10-10).

QImage.Format_A2BGR30_Premultiplied

The image is stored using a 32-bit premultiplied ABGR format (2-10-10-10).

QImage.Format_RGB30

The image is stored using a 32-bit RGB format (x-10-10-10).

QImage.Format_A2RGB30_Premultiplied

The image is stored using a 32-bit premultiplied ARGB format (2-10-10-10).

QImage.Format_Alpha8

The image is stored using an 8-bit alpha only format.

QImage.Format_Grayscale8

The image is stored using an 8-bit grayscale format.

QImage.Format_Grayscale16

The image is stored using an 16-bit grayscale format.

QImage.Format_RGBX64

The image is stored using a 64-bit halfword-ordered RGB(x) format (16-16-16-16). This is the same as the Format_RGBA64 except alpha must always be 65535.

QImage.Format_RGBA64

The image is stored using a 64-bit halfword-ordered RGBA format (16-16-16-16).

QImage.Format_RGBA64_Premultiplied

The image is stored using a premultiplied 64-bit halfword-ordered RGBA format (16-16-16-16).

QImage.Format_BGR888

The image is stored using a 24-bit BGR format.

QImage.Format_RGBX16FPx4

The image is stored using a four 16-bit halfword floating point RGBx format (16FP-16FP-16FP-16FP). This is the same as the Format_RGBA16FPx4 except alpha must always be 1.0.

QImage.Format_RGBA16FPx4

The image is stored using a four 16-bit halfword floating point RGBA format (16FP-16FP-16FP-16FP).

QImage.Format_RGBA16FPx4_Premultiplied

The image is stored using a premultiplied four 16-bit halfword floating point RGBA format (16FP-16FP-16FP-16FP).

QImage.Format_RGBX32FPx4

The image is stored using a four 32-bit floating point RGBx format (32FP-32FP-32FP-32FP). This is the same as the Format_RGBA32FPx4 except alpha must always be 1.0.

QImage.Format_RGBA32FPx4

The image is stored using a four 32-bit floating point RGBA format (32FP-32FP-32FP-32FP).

QImage.Format_RGBA32FPx4_Premultiplied

The image is stored using a premultiplied four 32-bit floating point RGBA format (32FP-32FP-32FP-32FP).

QImage.Format_CMYK8888

The image is stored using a 32-bit byte-ordered CMYK format.

Constant	Description
QImage.Format_Invalid	The image is invalid.
QImage.Format_Mono	The image is stored using 1-bit per pixel. Bytes are packed with the most significant bit (MSB) first.
QImage.Format_MonoLSB	The image is stored using 1-bit per pixel. Bytes are packed with the less significant bit (LSB) first.
QImage.Format_Indexed8	The image is stored using 8-bit indexes into a colormap.
QImage.Format_RGB32	The image is stored using a 32-bit RGB format (0xffRRGGBB).
QImage.Format_ARGB32	The image is stored using a 32-bit ARGB format (0xAARRGGBB).
QImage.Format_ARGB32_Premultiplied	The image is stored using a premultiplied 32-bit ARGB format (0xAARRGGBB), i.e. the red, green, and blue channels are multiplied by the alpha component divided by 255. (If RR, GG, or BB has a higher value than the alpha channel, the results are undefined.) Certain operations (such as image composition using alpha blending) are faster using premultiplied ARGB32 than with plain ARGB32.
QImage.Format_RGB16	The image is stored using a 16-bit RGB format (5-6-5).
QImage.Format_ARGB8565_Premultiplied	The image is stored using a premultiplied 24-bit ARGB format (8-5-6-5).
QImage.Format_RGB666	The image is stored using a 24-bit RGB format (6-6-6). The unused most significant bits is always zero.
QImage.Format_ARGB6666_Premultiplied	The image is stored using a premultiplied 24-bit ARGB format (6-6-6-6).
QImage.Format_RGB555	The image is stored using a 16-bit RGB format (5-5-5). The unused most significant bit is always zero.
QImage.Format_ARGB8555_Premultiplied	The image is stored using a premultiplied 24-bit ARGB format (8-5-5-5).
QImage.Format_RGB888	The image is stored using a 24-bit RGB format (8-8-8).
QImage.Format_RGB444	The image is stored using a 16-bit RGB format (4-4-4). The unused bits are always zero.
QImage.Format_ARGB4444_Premultiplied	The image is stored using a premultiplied 16-bit ARGB format (4-4-4-4).
QImage.Format_RGBX8888	The image is stored using a 32-bit byte-ordered RGB(x) format (8-8-8-8). This is the same as the Format_RGBA8888 except alpha must always be 255.
QImage.Format_RGBA8888	The image is stored using a 32-bit byte-ordered RGBA format (8-8-8-8). Unlike ARGB32 this is a byte-ordered format, which means the 32bit encoding differs between big endian and little endian architectures, being respectively (0xRRGGBBAA) and (0xAABBGGRR). The order of the colors is the same on any architecture if read as bytes 0xRR,0xGG,0xBB,0xAA.
QImage.Format_RGBA8888_Premultiplied	The image is stored using a premultiplied 32-bit byte-ordered RGBA format (8-8-8-8).
QImage.Format_BGR30	The image is stored using a 32-bit BGR format (x-10-10-10).
QImage.Format_A2BGR30_Premultiplied	The image is stored using a 32-bit premultiplied ABGR format (2-10-10-10).
QImage.Format_RGB30	The image is stored using a 32-bit RGB format (x-10-10-10).
QImage.Format_A2RGB30_Premultiplied	The image is stored using a 32-bit premultiplied ARGB format (2-10-10-10).
QImage.Format_Alpha8	The image is stored using an 8-bit alpha only format.
QImage.Format_Grayscale8	The image is stored using an 8-bit grayscale format.
QImage.Format_Grayscale16	The image is stored using an 16-bit grayscale format.
QImage.Format_RGBX64	The image is stored using a 64-bit halfword-ordered RGB(x) format (16-16-16-16). This is the same as the Format_RGBA64 except alpha must always be 65535.
QImage.Format_RGBA64	The image is stored using a 64-bit halfword-ordered RGBA format (16-16-16-16).
QImage.Format_RGBA64_Premultiplied	The image is stored using a premultiplied 64-bit halfword-ordered RGBA format (16-16-16-16).
QImage.Format_BGR888	The image is stored using a 24-bit BGR format.
QImage.Format_RGBX16FPx4	The image is stored using a four 16-bit halfword floating point RGBx format (16FP-16FP-16FP-16FP). This is the same as the Format_RGBA16FPx4 except alpha must always be 1.0.
QImage.Format_RGBA16FPx4	The image is stored using a four 16-bit halfword floating point RGBA format (16FP-16FP-16FP-16FP).
QImage.Format_RGBA16FPx4_Premultiplied	The image is stored using a premultiplied four 16-bit halfword floating point RGBA format (16FP-16FP-16FP-16FP).
QImage.Format_RGBX32FPx4	The image is stored using a four 32-bit floating point RGBx format (32FP-32FP-32FP-32FP). This is the same as the Format_RGBA32FPx4 except alpha must always be 1.0.
QImage.Format_RGBA32FPx4	The image is stored using a four 32-bit floating point RGBA format (32FP-32FP-32FP-32FP).
QImage.Format_RGBA32FPx4_Premultiplied	The image is stored using a premultiplied four 32-bit floating point RGBA format (32FP-32FP-32FP-32FP).
QImage.Format_CMYK8888	The image is stored using a 32-bit byte-ordered CMYK format.

Note

Drawing into a QImage with format QImage::Format_Indexed8 or QImage::Format_CMYK8888 is not supported.

Note

Avoid most rendering directly to most of these formats using QPainter . Rendering is best optimized to the Format_RGB32 and Format_ARGB32_Premultiplied formats, and secondarily for rendering to the Format_RGB16, Format_RGBX8888, Format_RGBA8888_Premultiplied, Format_RGBX64 and Format_RGBA64_Premultiplied formats

See also

convertToFormat()

__init__()¶

__init__(arg__1)

Parameters:: arg__1 – QImage

Constructs a shallow copy of the given image.

For more information about shallow copies, see the Implicit Data Sharing documentation.

See also

copy()

__init__(xpm)

Parameters:: xpm – char[]

__init__(size, format)

Parameters:

size – QSize
format – Format

__init__(fileName[, format=None])

Parameters:

fileName – str
format – str

__init__(width, height, format)

Parameters:

width – int
height – int
format – Format

__init__(arg__1, arg__2, arg__3, arg__4)

Parameters:

arg__1 – str
arg__2 – int
arg__3 – int
arg__4 – Format

__init__(arg__1, arg__2, arg__3, arg__4, arg__5)

Parameters:

arg__1 – str
arg__2 – int
arg__3 – int
arg__4 – int
arg__5 – Format

__init__(data, width, height, format[, cleanupFunction=None[, cleanupInfo=None]])

Parameters:

data – str
width – int
height – int
format – Format
cleanupFunction – QImageCleanupFunction
cleanupInfo – void

__init__(data, width, height, bytesPerLine, format[, cleanupFunction=None[, cleanupInfo=None]])

Parameters:

data – str
width – int
height – int
bytesPerLine – int
format – Format
cleanupFunction – QImageCleanupFunction
cleanupInfo – void

allGray()¶

Return type:: bool

applyColorTransform(transform)¶

Parameters:: transform – QColorTransform

applyColorTransform(transform, format[, flags=Qt.AutoColor])

Parameters:

transform – QColorTransform
format – Format
flags – Combination of ImageConversionFlag

bitPlaneCount()¶

Return type:: int

bytesPerLine()¶

Return type:: int

cacheKey()¶

Return type:: int

color(i)¶

Parameters:: i – int
Return type:: int

colorSpace()¶

Return type:: QColorSpace

colorTable()¶

Return type:: .list of unsigned int

colorTransformed(transform)¶

Parameters:: transform – QColorTransform
Return type:: QImage

colorTransformed(transform, format[, flags=Qt.AutoColor])

Parameters:

transform – QColorTransform
format – Format
flags – Combination of ImageConversionFlag

Return type:

QImage

constBits()¶

Return type:: str

constScanLine(arg__1)¶

Parameters:: arg__1 – int
Return type:: PyObject

convertTo(f[, flags=Qt.AutoColor])¶

Parameters:

f – Format
flags – Combination of ImageConversionFlag

convertToColorSpace(colorSpace)¶

Parameters:: colorSpace – QColorSpace

convertToColorSpace(colorSpace, format[, flags=Qt.AutoColor])

Parameters:

colorSpace – QColorSpace
format – Format
flags – Combination of ImageConversionFlag

convertToFormat(f[, flags=Qt.AutoColor])¶

Parameters:

f – Format
flags – Combination of ImageConversionFlag

Return type:

QImage

convertToFormat(f, colorTable[, flags=Qt.AutoColor])

Parameters:

f – Format
colorTable – .list of unsigned int
flags – Combination of ImageConversionFlag

Return type:

QImage

convertToFormat_helper(format, flags)¶

Parameters:

format – Format
flags – Combination of ImageConversionFlag

Return type:

QImage

convertToFormat_inplace(format, flags)¶

Parameters:

format – Format
flags – Combination of ImageConversionFlag

Return type:

bool

convertedTo(f[, flags=Qt.AutoColor])¶

Parameters:

f – Format
flags – Combination of ImageConversionFlag

Return type:

QImage

convertedToColorSpace(colorSpace)¶

Parameters:: colorSpace – QColorSpace
Return type:: QImage

convertedToColorSpace(colorSpace, format[, flags=Qt.AutoColor])

Parameters:

colorSpace – QColorSpace
format – Format
flags – Combination of ImageConversionFlag

Return type:

QImage

copy([rect=QRect()])¶

Parameters:: rect – QRect
Return type:: QImage

Returns a sub-area of the image as a new image.

The returned image is copied from the position (rectangle.x(), rectangle.y()) in this image, and will always have the size of the given rectangle.

In areas beyond this image, pixels are set to 0. For 32-bit RGB images, this means black; for 32-bit ARGB images, this means transparent black; for 8-bit images, this means the color with index 0 in the color table which can be anything; for 1-bit images, this means Qt::color0.

If the given rectangle is a null rectangle the entire image is copied.

See also

QImage()

copy(x, y, w, h)

Parameters:

x – int
y – int
w – int
h – int

Return type:

QImage

This is an overloaded function.

The returned image is copied from the position (x, y) in this image, and will always have the given width and height. In areas beyond this image, pixels are set to 0.

createAlphaMask([flags=Qt.AutoColor])¶

Parameters:: flags – Combination of ImageConversionFlag
Return type:: QImage

createHeuristicMask([clipTight=true])¶

Parameters:: clipTight – bool
Return type:: QImage

createMaskFromColor(color[, mode=Qt.MaskInColor])¶

Parameters:

color – int
mode – MaskMode

Return type:

QImage

detachMetadata([invalidateCache=false])¶

Parameters:: invalidateCache – bool

deviceIndependentSize()¶

Return type:: QSizeF

dotsPerMeterX()¶

Return type:: int

dotsPerMeterY()¶

Return type:: int

fill(color)¶

Parameters:: color – GlobalColor

This is an overloaded function.

Fills the image with the given color, described as a standard global color.

fill(color)

Parameters:: color – QColor

This is an overloaded function.

Fills the entire image with the given color.

If the depth of the image is 1, the image will be filled with 1 if color equals Qt::color1; it will otherwise be filled with 0.

If the depth of the image is 8, the image will be filled with the index corresponding the color in the color table if present; it will otherwise be filled with 0.

fill(pixel)

Parameters:: pixel – int

Fills the entire image with the given pixelValue.

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 and if the depth is 16 the lowest 16 bits are used.

If the image depth is higher than 32bit the result is undefined.

Note

There are no corresponding value getter, though pixelIndex() will return the same value for indexed formats, and pixel() for RGB32, ARGB32, and ARGB32PM formats.

See also

depth() Image Transformations

format()¶

Return type:: Format

static fromData(data[, format=None])¶

Parameters:

data – QByteArrayView
format – str

Return type:

QImage

This is an overloaded function.

Constructs a QImage from the given QByteArray data.

static fromData(data[, format=None])

Parameters:

data – QByteArray
format – str

Return type:

QImage

This is an overloaded function.

Constructs a QImage from the given QByteArray data.

hasAlphaChannel()¶

Return type:: bool

invertPixels([mode=QImage.InvertMode.InvertRgb])¶

Parameters:: mode – InvertMode

isGrayscale()¶

Return type:: bool

isNull()¶

Return type:: bool

Returns true if it is a null image, otherwise returns false.

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

load(device, format)¶

Parameters:

device – QIODevice
format – str

Return type:

bool

load(fileName[, format=None])

Parameters:

fileName – str
format – str

Return type:

bool

loadFromData(data[, format=None])¶

Parameters:

data – QByteArrayView
format – str

Return type:

bool

This is an overloaded function.

Loads an image from the given QByteArray data.

loadFromData(data[, format=None])

Parameters:

data – QByteArray
format – str

Return type:

bool

This is an overloaded function.

Loads an image from the given QByteArray data.

mirror([horizontally=false[, vertically=true]])¶

Parameters:

horizontally – bool
vertically – bool

Mirrors of the image in the horizontal and/or the vertical direction depending on whether horizontal and vertical are set to true or false.

See also

mirrored() Image Transformations

mirrored([horizontally=false[, vertically=true]])¶

Parameters:

horizontally – bool
vertically – bool

Return type:

QImage

mirrored_helper(horizontal, vertical)¶

Parameters:

horizontal – bool
vertical – bool

Return type:

QImage

mirrored_inplace(horizontal, vertical)¶

Parameters:

horizontal – bool
vertical – bool

offset()¶

Return type:: QPoint

Returns the number of pixels by which the image is intended to be offset by when positioning relative to other images.

See also

setOffset() Image Information

__ne__(arg__1)¶

Parameters:: arg__1 – QImage
Return type:: bool

Returns true if this image and the given image 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=()

__eq__(arg__1)¶

Parameters:: arg__1 – QImage
Return type:: bool

Returns true if this image and the given image have the same contents; otherwise returns false.

The comparison can be slow, unless there is some obvious difference (e.g. different size or format), in which case the function will return quickly.

See also

operator=()

pixel(pt)¶

Parameters:: pt – QPoint
Return type:: int

Returns the color of the pixel at the given position.

If the position is not valid, the results are undefined.

Warning

This function is expensive when used for massive pixel manipulations. Use constBits() or constScanLine() when many pixels needs to be read.

See also

setPixel() valid() Pixel Manipulation

pixel(x, y)

Parameters:

x – int
y – int

Return type:

int

pixelColor(pt)¶

Parameters:: pt – QPoint
Return type:: QColor

Returns the color of the pixel at the given position as a QColor .

If the position is not valid, an invalid QColor is returned.

Warning

This function is expensive when used for massive pixel manipulations. Use constBits() or constScanLine() when many pixels needs to be read.

See also

setPixelColor() setPixel() valid() Pixel Manipulation

pixelColor(x, y)

Parameters:

x – int
y – int

Return type:

QColor

pixelFormat()¶

Return type:: QPixelFormat

Returns the Format as a QPixelFormat

pixelIndex(pt)¶

Parameters:: pt – QPoint
Return type:: int

Returns the pixel index at the given position.

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

See also

valid() depth() Pixel Manipulation

pixelIndex(x, y)

Parameters:

x – int
y – int

Return type:

int

rect()¶

Return type:: QRect

Returns the enclosing rectangle (0, 0, width() , height() ) of the image.

See also

Image Information

reinterpretAsFormat(f)¶

Parameters:: f – Format
Return type:: bool

rgbSwap()¶

Swaps the values of the red and blue components of all pixels, effectively converting an RGB image to an BGR image.

See also

rgbSwapped() Image Transformations

rgbSwapped()¶

Return type:: QImage

rgbSwapped_helper()¶

Return type:: QImage

rgbSwapped_inplace()¶

save(device[, format=None[, quality=-1]])¶

Parameters:

device – QIODevice
format – str
quality – int

Return type:

bool

save(fileName[, format=None[, quality=-1]])

Parameters:

fileName – str
format – str
quality – int

Return type:

bool

scaled(s[, aspectMode=Qt.IgnoreAspectRatio[, mode=Qt.FastTransformation]])¶

Parameters:

s – QSize
aspectMode – AspectRatioMode
mode – TransformationMode

Return type:

QImage

Returns a copy of the image scaled to a rectangle defined by the given size according to the given aspectRatioMode and transformMode.

If aspectRatioMode is Qt::IgnoreAspectRatio, the image is scaled to size.

If aspectRatioMode is Qt::KeepAspectRatio, the image is scaled to a rectangle as large as possible inside size, preserving the aspect ratio.

If aspectRatioMode is Qt::KeepAspectRatioByExpanding, the image is scaled to a rectangle as small as possible outside size, preserving the aspect ratio.

If the given size is empty, this function returns a null image.

See also

isNull() Image Transformations

scaled(w, h[, aspectMode=Qt.IgnoreAspectRatio[, mode=Qt.FastTransformation]])

Parameters:

w – int
h – int
aspectMode – AspectRatioMode
mode – TransformationMode

Return type:

QImage

This is an overloaded function.

Returns a copy of the image scaled to a rectangle with the given width and height according to the given aspectRatioMode and transformMode.

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

scaledToHeight(h[, mode=Qt.FastTransformation])¶

Parameters:

h – int
mode – TransformationMode

Return type:

QImage

Returns a scaled copy of the image. The returned image is scaled to the given height using the specified transformation mode.

This function automatically calculates the width of the image so that the ratio of the image is preserved.

If the given height is 0 or negative, a null image is returned.

See also

Image Transformations

scaledToWidth(w[, mode=Qt.FastTransformation])¶

Parameters:

w – int
mode – TransformationMode

Return type:

QImage

Returns a scaled copy of the image. The returned image is scaled to the given width using the specified transformation mode.

This function automatically calculates the height of the image so that its aspect ratio is preserved.

If the given width is 0 or negative, a null image is returned.

See also

Image Transformations

setAlphaChannel(alphaChannel)¶

Parameters:: alphaChannel – QImage

setColor(i, c)¶

Parameters:

i – int
c – int

Sets the color at the given index in the color table, to the given to colorValue. The color value is an ARGB quadruplet.

If index is outside the current size of the color table, it is expanded with setColorCount().

See also

colorCount() Pixel Manipulation

setColorCount(arg__1)¶

Parameters:: arg__1 – int

setColorSpace(colorSpace)¶

Parameters:: colorSpace – QColorSpace

setColorTable(colors)¶

Parameters:: colors – .list of unsigned int

setDevicePixelRatio(scaleFactor)¶

Parameters:: scaleFactor – float

setDotsPerMeterX(arg__1)¶

Parameters:: arg__1 – int

setDotsPerMeterY(arg__1)¶

Parameters:: arg__1 – int

setOffset(arg__1)¶

Parameters:: arg__1 – QPoint

Sets the number of pixels by which the image is intended to be offset by when positioning relative to other images, to offset.

See also

offset() Image Information

setPixel(pt, index_or_rgb)¶

Parameters:

pt – QPoint
index_or_rgb – int

Sets the pixel index or color at the given position to index_or_rgb.

If the image’s format is either monochrome or paletted, the given index_or_rgb value must be an index in the image’s color table, otherwise the parameter must be a QRgb value.

If position is not a valid coordinate pair in the image, or if index_or_rgb >= colorCount() in the case of monochrome and paletted images, the result is undefined.

Warning

This function is expensive due to the call of the internal detach() function called within; if performance is a concern, we recommend the use of scanLine() or bits() to access pixel data directly.

See also

pixel() Pixel Manipulation

setPixel(x, y, index_or_rgb)

Parameters:

x – int
y – int
index_or_rgb – int

setPixelColor(pt, c)¶

Parameters:

pt – QPoint
c – QColor

Sets the color at the given position to color.

If position is not a valid coordinate pair in the image, or the image’s format is either monochrome or paletted, the result is undefined.

Warning

This function is expensive due to the call of the internal detach() function called within; if performance is a concern, we recommend the use of scanLine() or bits() to access pixel data directly.

See also

pixelColor() pixel() Pixel Manipulation

setPixelColor(x, y, c)

Parameters:

x – int
y – int
c – QColor

setText(key, value)¶

Parameters:

key – str
value – str

Warning

This section contains snippets that were automatically translated from C++ to Python and may contain errors.

Sets the image text to the given text and associate it with the given key.

If you just want to store a single text block (i.e., a “comment” or just a description), you can either pass an empty key, or use a generic key like “Description”.

The image text is embedded into the image data when you call save() or write() .

Not all image formats support embedded text. You can find out if a specific image or format supports embedding text by using supportsOption() . We give an example:

writer = QImageWriter()
writer.setFormat("png")
if writer.supportsOption(QImageIOHandler.Description):
    print("Png supports embedded text")

You can use supportedImageFormats() to find out which image formats are available to you.

See also

text()textKeys()

size()¶

Return type:: QSize

Returns the size of the image, i.e. its width() and height() .

See also

Image Information deviceIndependentSize()

sizeInBytes()¶

Return type:: int

smoothScaled(w, h)¶

Parameters:

w – int
h – int

Return type:

QImage

swap(other)¶

Parameters:: other – QImage

Swaps image other with this image. This operation is very fast and never fails.

text([key=""])¶

Parameters:: key – str
Return type:: str

textKeys()¶

Return type:: list of strings

static toImageFormat(format)¶

Parameters:: format – QPixelFormat
Return type:: Format

Converts format into a Format

static toPixelFormat(format)¶

Parameters:: format – Format
Return type:: QPixelFormat

Converts format into a QPixelFormat

transformed(matrix[, mode=Qt.FastTransformation])¶

Parameters:

matrix – QTransform
mode – TransformationMode

Return type:

QImage

static trueMatrix(arg__1, w, h)¶

Parameters:

arg__1 – QTransform
w – int
h – int

Return type:

QTransform

Returns the actual matrix used for transforming an image with the given width, height and matrix.

When transforming an image using the transformed() function, the transformation matrix is internally adjusted to compensate for unwanted translation, i.e. transformed() returns the smallest image containing all transformed points of the original image. This function returns the modified matrix, which maps points correctly from the original image into the new image.

Unlike the other overload, this function creates transformation matrices that can be used to perform perspective transformations on images.

See also

Image Transformations

valid(pt)¶

Parameters:: pt – QPoint
Return type:: bool

Returns true if pos is a valid coordinate pair within the image; otherwise returns false.

See also

rect() contains()

valid(x, y)

Parameters:

x – int
y – int

Return type:

bool