gi-gdkpixbuf-2.0.26: GdkPixbuf bindings
Copyright Will Thompson Iñaki García Etxebarria and Jonas Platte LGPL-2.1 Iñaki García Etxebarria Safe-Inferred Haskell2010

GI.GdkPixbuf.Objects.Pixbuf

Description

A pixel buffer.

GdkPixbuf contains information about an image's pixel data, its color space, bits per sample, width and height, and the rowstride (the number of bytes between the start of one row and the start of the next).

## Creating new GdkPixbuf

The most basic way to create a pixbuf is to wrap an existing pixel buffer with a [classgdkPixbuf.Pixbuf] instance. You can use the [ctor@GdkPixbuf.Pixbuf.new_from_data] function to do this.

Every time you create a new GdkPixbuf instance for some data, you will need to specify the destroy notification function that will be called when the data buffer needs to be freed; this will happen when a GdkPixbuf is finalized by the reference counting functions. If you have a chunk of static data compiled into your application, you can pass in NULL as the destroy notification function so that the data will not be freed.

The [ctor@GdkPixbuf.Pixbuf.new] constructor function can be used as a convenience to create a pixbuf with an empty buffer; this is equivalent to allocating a data buffer using malloc() and then wrapping it with gdk_pixbuf_new_from_data(). The gdk_pixbuf_new() function will compute an optimal rowstride so that rendering can be performed with an efficient algorithm.

As a special case, you can use the [ctor@GdkPixbuf.Pixbuf.new_from_xpm_data] function to create a pixbuf from inline XPM image data.

You can also copy an existing pixbuf with the [methodpixbuf.copy] function. This is not the same as just acquiring a reference to the old pixbuf instance: the copy function will actually duplicate the pixel data in memory and create a new [classpixbuf] instance for it.

## Reference counting

GdkPixbuf structures are reference counted. This means that an application can share a single pixbuf among many parts of the code. When a piece of the program needs to use a pixbuf, it should acquire a reference to it by calling g_object_ref(); when it no longer needs the pixbuf, it should release the reference it acquired by calling g_object_unref(). The resources associated with a GdkPixbuf will be freed when its reference count drops to zero. Newly-created GdkPixbuf instances start with a reference count of one.

## Image Data

Image data in a pixbuf is stored in memory in an uncompressed, packed format. Rows in the image are stored top to bottom, and in each row pixels are stored from left to right.

There may be padding at the end of a row.

The "rowstride" value of a pixbuf, as returned by [method@GdkPixbuf.Pixbuf.get_rowstride], indicates the number of bytes between rows.

• *NOTE**: If you are copying raw pixbuf data with memcpy() note that the last row in the pixbuf may not be as wide as the full rowstride, but rather just as wide as the pixel data needs to be; that is: it is unsafe to do memcpy (dest, pixels, rowstride * height) to copy a whole pixbuf. Use [methodgdkPixbuf.Pixbuf.copy] instead, or compute the width in bytes of the last row as:

c last_row = width * ((n_channels * bits_per_sample + 7) / 8); @

The same rule applies when iterating over each row of a GdkPixbuf pixels array.

The following code illustrates a simple @put_pixel()@ function for RGB pixbufs with 8 bits per channel with an alpha channel.

c static void put_pixel (GdkPixbuf *pixbuf, int x, int y, guchar red, guchar green, guchar blue, guchar alpha) { int n_channels = gdk_pixbuf_get_n_channels (pixbuf);

// Ensure that the pixbuf is valid g_assert (gdk_pixbuf_get_colorspace (pixbuf) == GDK_COLORSPACE_RGB); g_assert (gdk_pixbuf_get_bits_per_sample (pixbuf) == 8); g_assert (gdk_pixbuf_get_has_alpha (pixbuf)); g_assert (n_channels == 4);

int width = gdk_pixbuf_get_width (pixbuf); int height = gdk_pixbuf_get_height (pixbuf);

// Ensure that the coordinates are in a valid range g_assert (x >= 0 && x < width); g_assert (y >= 0 && y < height);

int rowstride = gdk_pixbuf_get_rowstride (pixbuf);

// The pixel buffer in the GdkPixbuf instance guchar *pixels = gdk_pixbuf_get_pixels (pixbuf);

// The pixel we wish to modify guchar *p = pixels + y * rowstride + x * n_channels; p[0] = red; p[1] = green; p[2] = blue; p[3] = alpha; } 

The GdkPixBuf class provides a simple mechanism for loading an image from a file in synchronous and asynchronous fashion.

For GUI applications, it is recommended to use the asynchronous stream API to avoid blocking the control flow of the application.

Additionally, GdkPixbuf provides the [class@GdkPixbuf.PixbufLoader@] API for progressive image loading.

## Saving images

The GdkPixbuf class provides methods for saving image data in a number of file formats. The formatted data can be written to a file or to a memory buffer. GdkPixbuf can also call a user-defined callback on the data, which allows to e.g. write the image to a socket or store it in a database.

Synopsis

# Exported types

newtype Pixbuf Source #

Memory-managed wrapper type.

Constructors

 Pixbuf (ManagedPtr Pixbuf)

#### Instances

Instances details
 Source # Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf Methods(==) :: Pixbuf -> Pixbuf -> Bool #(/=) :: Pixbuf -> Pixbuf -> Bool # GObject Pixbuf Source # Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf ManagedPtrNewtype Pixbuf Source # Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf MethodstoManagedPtr :: Pixbuf -> ManagedPtr Pixbuf TypedObject Pixbuf Source # Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf MethodsglibType :: IO GType HasParentTypes Pixbuf Source # Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf IsGValue (Maybe Pixbuf) Source # Convert Pixbuf to and from GValue. See toGValue and fromGValue. Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf MethodsgvalueGType_ :: IO GTypegvalueSet_ :: Ptr GValue -> Maybe Pixbuf -> IO ()gvalueGet_ :: Ptr GValue -> IO (Maybe Pixbuf) type ParentTypes Pixbuf Source # Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf type ParentTypes Pixbuf = '[Object, Icon, LoadableIcon]

class (GObject o, IsDescendantOf Pixbuf o) => IsPixbuf o Source #

Type class for types which can be safely cast to Pixbuf, for instance with toPixbuf.

#### Instances

Instances details
 (GObject o, IsDescendantOf Pixbuf o) => IsPixbuf o Source # Instance detailsDefined in GI.GdkPixbuf.Objects.Pixbuf

toPixbuf :: (MonadIO m, IsPixbuf o) => o -> m Pixbuf Source #

Cast to Pixbuf, for types for which this is known to be safe. For general casts, use castTo.

# Methods

### Click to display all available methods, including inherited ones

Expand

#### Setters

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A Pixbuf. -> Bool substituteColor: Whether to set a color to zero opacity. -> Word8 r: Red value to substitute. -> Word8 g: Green value to substitute. -> Word8 b: Blue value to substitute. -> m Pixbuf Returns: A newly-created pixbuf

Takes an existing pixbuf and adds an alpha channel to it.

If the existing pixbuf already had an alpha channel, the channel values are copied from the original; otherwise, the alpha channel is initialized to 255 (full opacity).

If substitute_color is TRUE, then the color specified by the (r, g, b) arguments will be assigned zero opacity. That is, if you pass (255, 255, 255) for the substitute color, all white pixels will become fully transparent.

If substitute_color is FALSE, then the (r, g, b) arguments will be ignored.

## applyEmbeddedOrientation

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a src: a pixbuf with an orientation option -> m (Maybe Pixbuf) Returns: A newly-created pixbuf

Takes an existing pixbuf and checks for the presence of an associated "orientation" option.

The orientation option may be provided by the JPEG loader (which reads the exif orientation tag) or the TIFF loader (which reads the TIFF orientation tag, and compensates it for the partial transforms performed by libtiff).

If an orientation option/tag is present, the appropriate transform will be performed so that the pixbuf is oriented correctly.

Since: 2.12

## calculateRowstride

Arguments

 :: (HasCallStack, MonadIO m) => Colorspace colorspace: Color space for image -> Bool hasAlpha: Whether the image should have transparency information -> Int32 bitsPerSample: Number of bits per color sample -> Int32 width: Width of image in pixels, must be > 0 -> Int32 height: Height of image in pixels, must be > 0 -> m Int32 Returns: the rowstride for the given values, or -1 in case of error.

Calculates the rowstride that an image created with those values would have.

This function is useful for front-ends and backends that want to check image values without needing to create a GdkPixbuf.

Since: 2.36.8

## composite

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsPixbuf b) => a src: a Pixbuf -> b dest: the Pixbuf into which to render the results -> Int32 destX: the left coordinate for region to render -> Int32 destY: the top coordinate for region to render -> Int32 destWidth: the width of the region to render -> Int32 destHeight: the height of the region to render -> Double offsetX: the offset in the X direction (currently rounded to an integer) -> Double offsetY: the offset in the Y direction (currently rounded to an integer) -> Double scaleX: the scale factor in the X direction -> Double scaleY: the scale factor in the Y direction -> InterpType interpType: the interpolation type for the transformation. -> Int32 overallAlpha: overall alpha for source image (0..255) -> m ()

Creates a transformation of the source image src by scaling by scaleX and scaleY then translating by offsetX and offsetY.

This gives an image in the coordinates of the destination pixbuf. The rectangle (destX, destY, destWidth, destHeight) is then alpha blended onto the corresponding rectangle of the original destination image.

When the destination rectangle contains parts not in the source image, the data at the edges of the source image is replicated to infinity.

## compositeColor

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsPixbuf b) => a src: a Pixbuf -> b dest: the Pixbuf into which to render the results -> Int32 destX: the left coordinate for region to render -> Int32 destY: the top coordinate for region to render -> Int32 destWidth: the width of the region to render -> Int32 destHeight: the height of the region to render -> Double offsetX: the offset in the X direction (currently rounded to an integer) -> Double offsetY: the offset in the Y direction (currently rounded to an integer) -> Double scaleX: the scale factor in the X direction -> Double scaleY: the scale factor in the Y direction -> InterpType interpType: the interpolation type for the transformation. -> Int32 overallAlpha: overall alpha for source image (0..255) -> Int32 checkX: the X offset for the checkboard (origin of checkboard is at -checkX, -checkY) -> Int32 checkY: the Y offset for the checkboard -> Int32 checkSize: the size of checks in the checkboard (must be a power of two) -> Word32 color1: the color of check at upper left -> Word32 color2: the color of the other check -> m ()

Creates a transformation of the source image src by scaling by scaleX and scaleY then translating by offsetX and offsetY, then alpha blends the rectangle (destX ,destY, destWidth, destHeight) of the resulting image with a checkboard of the colors color1 and color2 and renders it onto the destination image.

If the source image has no alpha channel, and overallAlpha is 255, a fast path is used which omits the alpha blending and just performs the scaling.

See pixbufCompositeColorSimple for a simpler variant of this function suitable for many tasks.

## compositeColorSimple

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a src: a Pixbuf -> Int32 destWidth: the width of destination image -> Int32 destHeight: the height of destination image -> InterpType interpType: the interpolation type for the transformation. -> Int32 overallAlpha: overall alpha for source image (0..255) -> Int32 checkSize: the size of checks in the checkboard (must be a power of two) -> Word32 color1: the color of check at upper left -> Word32 color2: the color of the other check -> m (Maybe Pixbuf) Returns: the new pixbuf

Creates a new pixbuf by scaling src to dest_width x dest_height and alpha blending the result with a checkboard of colors color1 and color2.

## copy

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m (Maybe Pixbuf) Returns: A newly-created pixbuf

Creates a new GdkPixbuf with a copy of the information in the specified pixbuf.

Note that this does not copy the options set on the original GdkPixbuf, use pixbufCopyOptions for this.

## copyArea

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsPixbuf b) => a srcPixbuf: Source pixbuf. -> Int32 srcX: Source X coordinate within srcPixbuf. -> Int32 srcY: Source Y coordinate within srcPixbuf. -> Int32 width: Width of the area to copy. -> Int32 height: Height of the area to copy. -> b destPixbuf: Destination pixbuf. -> Int32 destX: X coordinate within destPixbuf. -> Int32 destY: Y coordinate within destPixbuf. -> m ()

Copies a rectangular area from src_pixbuf to dest_pixbuf.

Conversion of pixbuf formats is done automatically.

If the source rectangle overlaps the destination rectangle on the same pixbuf, it will be overwritten during the copy operation. Therefore, you can not use this function to scroll a pixbuf.

## copyOptions

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsPixbuf b) => a srcPixbuf: the source pixbuf -> b destPixbuf: the destination pixbuf -> m Bool Returns: TRUE on success.

Copies the key/value pair options attached to a GdkPixbuf to another GdkPixbuf.

This is useful to keep original metadata after having manipulated a file. However be careful to remove metadata which you've already applied, such as the "orientation" option after rotating the image.

Since: 2.36

## fill

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: a GdkPixbuf -> Word32 pixel: RGBA pixel to used to clear (0xffffffff is opaque white, 0x00000000 transparent black) -> m ()

Clears a pixbuf to the given RGBA value, converting the RGBA value into the pixbuf's pixel format.

The alpha component will be ignored if the pixbuf doesn't have an alpha channel.

## flip

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a src: a Pixbuf -> Bool horizontal: TRUE to flip horizontally, FALSE to flip vertically -> m (Maybe Pixbuf) Returns: the new pixbuf

Flips a pixbuf horizontally or vertically and returns the result in a new pixbuf.

Since: 2.6

## getBitsPerSample

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m Int32 Returns: Number of bits per color sample.

Queries the number of bits per color sample in a pixbuf.

## getByteLength

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf -> m Word64 Returns: The length of the pixel data.

Returns the length of the pixel data, in bytes.

Since: 2.26

## getColorspace

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m Colorspace Returns: Color space.

Queries the color space of a pixbuf.

## getFileInfo

Arguments

 :: (HasCallStack, MonadIO m) => [Char] filename: The name of the file to identify. -> m (Maybe PixbufFormat, Int32, Int32) Returns: A GdkPixbufFormat describing the image format of the file

Parses an image file far enough to determine its format and size.

Since: 2.4

## getFileInfoAsync

Arguments

 :: (HasCallStack, MonadIO m, IsCancellable a) => [Char] filename: The name of the file to identify -> Maybe a cancellable: optional GCancellable object, NULL to ignore -> Maybe AsyncReadyCallback callback: a GAsyncReadyCallback to call when the file info is available -> m ()

Asynchronously parses an image file far enough to determine its format and size.

For more details see pixbufGetFileInfo, which is the synchronous version of this function.

When the operation is finished, callback will be called in the main thread. You can then call pixbufGetFileInfoFinish to get the result of the operation.

Since: 2.32

## getFileInfoFinish

Arguments

 :: (HasCallStack, MonadIO m, IsAsyncResult a) => a asyncResult: a GAsyncResult -> m (Maybe PixbufFormat, Int32, Int32) Returns: A GdkPixbufFormat describing the image format of the file (Can throw GError)

Finishes an asynchronous pixbuf parsing operation started with pixbufGetFileInfoAsync.

Since: 2.32

## getFormats

Arguments

 :: (HasCallStack, MonadIO m) => m [PixbufFormat] Returns: A list of support image formats.

Obtains the available information about the image formats supported by GdkPixbuf.

Since: 2.2

## getHasAlpha

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m Bool Returns: TRUE if it has an alpha channel, FALSE otherwise.

Queries whether a pixbuf has an alpha channel (opacity information).

## getHeight

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m Int32 Returns: Height in pixels.

Queries the height of a pixbuf.

## getNChannels

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m Int32 Returns: Number of channels.

Queries the number of channels of a pixbuf.

## getOption

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: a GdkPixbuf -> Text key: a nul-terminated string. -> m (Maybe Text) Returns: the value associated with key

Looks up key in the list of options that may have been attached to the pixbuf when it was loaded, or that may have been attached by another function using pixbufSetOption.

For instance, the ANI loader provides "Title" and "Artist" options. The ICO, XBM, and XPM loaders provide "x_hot" and "y_hot" hot-spot options for cursor definitions. The PNG loader provides the tEXt ancillary chunk key/value pairs as options. Since 2.12, the TIFF and JPEG loaders return an "orientation" option string that corresponds to the embedded TIFF/Exif orientation tag (if present). Since 2.32, the TIFF loader sets the "multipage" option string to "yes" when a multi-page TIFF is loaded. Since 2.32 the JPEG and PNG loaders set "x-dpi" and "y-dpi" if the file contains image density information in dots per inch. Since 2.36.6, the JPEG loader sets the "comment" option with the comment EXIF tag.

## getPixels

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m ByteString Returns: A pointer to the pixbuf's pixel data.

Queries a pointer to the pixel data of a pixbuf.

This function will cause an implicit copy of the pixbuf data if the pixbuf was created from read-only data.

Please see the section on image data for information about how the pixel data is stored in memory.

Since: 2.26

## getRowstride

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m Int32 Returns: Distance between row starts.

Queries the rowstride of a pixbuf, which is the number of bytes between the start of a row and the start of the next row.

## getWidth

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf. -> m Int32 Returns: Width in pixels.

Queries the width of a pixbuf.

## initModules

Arguments

 :: (HasCallStack, MonadIO m) => Text path: Path to directory where the loaders.cache is installed -> m () (Can throw GError)

Initalizes the gdk-pixbuf loader modules referenced by the loaders.cache file present inside that directory.

This is to be used by applications that want to ship certain loaders in a different location from the system ones.

This is needed when the OS or runtime ships a minimal number of loaders so as to reduce the potential attack surface of carefully crafted image files, especially for uncommon file types. Applications that require broader image file types coverage, such as image viewers, would be expected to ship the gdk-pixbuf modules in a separate location, bundled with the application in a separate directory from the OS or runtime- provided modules.

Since: 2.40

## new

Arguments

 :: (HasCallStack, MonadIO m) => Colorspace colorspace: Color space for image -> Bool hasAlpha: Whether the image should have transparency information -> Int32 bitsPerSample: Number of bits per color sample -> Int32 width: Width of image in pixels, must be > 0 -> Int32 height: Height of image in pixels, must be > 0 -> m (Maybe Pixbuf) Returns: A newly-created pixel buffer

Creates a new GdkPixbuf structure and allocates a buffer for it.

If the allocation of the buffer failed, this function will return NULL.

The buffer has an optimal rowstride. Note that the buffer is not cleared; you will have to fill it completely yourself.

## newFromBytes

Arguments

 :: (HasCallStack, MonadIO m) => Bytes data: Image data in 8-bit/sample packed format inside a Bytes -> Colorspace colorspace: Colorspace for the image data -> Bool hasAlpha: Whether the data has an opacity channel -> Int32 bitsPerSample: Number of bits per sample -> Int32 width: Width of the image in pixels, must be > 0 -> Int32 height: Height of the image in pixels, must be > 0 -> Int32 rowstride: Distance in bytes between row starts -> m Pixbuf Returns: A newly-created pixbuf

Creates a new Pixbuf out of in-memory readonly image data.

Currently only RGB images with 8 bits per sample are supported.

This is the GBytes variant of pixbufNewFromData, useful for language bindings.

Since: 2.32

## newFromData

Arguments

 :: (HasCallStack, MonadIO m) => Ptr Word8 data: Image data in 8-bit/sample packed format -> Colorspace colorspace: Colorspace for the image data -> Bool hasAlpha: Whether the data has an opacity channel -> Int32 bitsPerSample: Number of bits per sample -> Int32 width: Width of the image in pixels, must be > 0 -> Int32 height: Height of the image in pixels, must be > 0 -> Int32 rowstride: Distance in bytes between row starts -> Maybe PixbufDestroyNotify destroyFn: Function used to free the data when the pixbuf's reference count drops to zero, or Nothing if the data should not be freed -> m Pixbuf Returns: A newly-created pixbuf

Creates a new Pixbuf out of in-memory image data.

Currently only RGB images with 8 bits per sample are supported.

Since you are providing a pre-allocated pixel buffer, you must also specify a way to free that data. This is done with a function of type GdkPixbufDestroyNotify. When a pixbuf created with is finalized, your destroy notification function will be called, and it is its responsibility to free the pixel array.

See also: [ctorgdkPixbuf.Pixbuf.new_from_bytes]

## newFromFile

Arguments

 :: (HasCallStack, MonadIO m) => [Char] filename: Name of file to load, in the GLib file name encoding -> m (Maybe Pixbuf) Returns: A newly-created pixbuf (Can throw GError)

The file format is detected automatically.

If NULL is returned, then error will be set. Possible errors are:

• the file could not be opened
• there is no loader for the file's format
• there is not enough memory to allocate the image buffer
• the image buffer contains invalid data

The error domains are GDK_PIXBUF_ERROR and G_FILE_ERROR.

## newFromFileAtScale

Arguments

 :: (HasCallStack, MonadIO m) => [Char] filename: Name of file to load, in the GLib file name encoding -> Int32 width: The width the image should have or -1 to not constrain the width -> Int32 height: The height the image should have or -1 to not constrain the height -> Bool preserveAspectRatio: TRUE to preserve the image's aspect ratio -> m (Maybe Pixbuf) Returns: A newly-created pixbuf (Can throw GError)

The file format is detected automatically.

If NULL is returned, then error will be set. Possible errors are:

• the file could not be opened
• there is no loader for the file's format
• there is not enough memory to allocate the image buffer
• the image buffer contains invalid data

The error domains are GDK_PIXBUF_ERROR and G_FILE_ERROR.

The image will be scaled to fit in the requested size, optionally preserving the image's aspect ratio.

When preserving the aspect ratio, a width of -1 will cause the image to be scaled to the exact given height, and a height of -1 will cause the image to be scaled to the exact given width. When not preserving aspect ratio, a width or height of -1 means to not scale the image at all in that dimension. Negative values for width and height are allowed since 2.8.

Since: 2.6

## newFromFileAtSize

Arguments

 :: (HasCallStack, MonadIO m) => [Char] filename: Name of file to load, in the GLib file name encoding -> Int32 width: The width the image should have or -1 to not constrain the width -> Int32 height: The height the image should have or -1 to not constrain the height -> m (Maybe Pixbuf) Returns: A newly-created pixbuf (Can throw GError)

The file format is detected automatically.

If NULL is returned, then error will be set. Possible errors are:

• the file could not be opened
• there is no loader for the file's format
• there is not enough memory to allocate the image buffer
• the image buffer contains invalid data

The error domains are GDK_PIXBUF_ERROR and G_FILE_ERROR.

The image will be scaled to fit in the requested size, preserving the image's aspect ratio. Note that the returned pixbuf may be smaller than width x height, if the aspect ratio requires it. To load and image at the requested size, regardless of aspect ratio, use [ctorgdkPixbuf.Pixbuf.new_from_file_at_scale].

Since: 2.4

## newFromInline

Arguments

 :: (HasCallStack, MonadIO m) => ByteString data: Byte data containing a serialized GdkPixdata structure -> Bool copyPixels: Whether to copy the pixel data, or use direct pointers data for the resulting pixbuf -> m Pixbuf Returns: A newly-created pixbuf (Can throw GError)

Deprecated: (Since version 2.32)Use GResource instead.

Creates a GdkPixbuf from a flat representation that is suitable for storing as inline data in a program.

This is useful if you want to ship a program with images, but don't want to depend on any external files.

GdkPixbuf ships with a program called gdk-pixbuf-csource, which allows for conversion of GdkPixbufs into such a inline representation.

In almost all cases, you should pass the --raw option to gdk-pixbuf-csource. A sample invocation would be:

 gdk-pixbuf-csource --raw --name=myimage_inline myimage.png @

For the typical case where the inline pixbuf is read-only static data, you don't need to copy the pixel data unless you intend to write to it, so you can pass FALSE for copy_pixels. If you pass --rle to gdk-pixbuf-csource, a copy will be made even if copy_pixels is FALSE, so using this option is generally a bad idea.

If you create a pixbuf from const inline data compiled into your program, it's probably safe to ignore errors and disable length checks, since things will always succeed:

c pixbuf = gdk_pixbuf_new_from_inline (-1, myimage_inline, FALSE, NULL); @

For non-const inline data, you could get out of memory. For untrusted inline data located at runtime, you could have corrupt inline data in addition.

## newFromResource

Arguments

 :: (HasCallStack, MonadIO m) => Text resourcePath: the path of the resource file -> m (Maybe Pixbuf) Returns: A newly-created pixbuf (Can throw GError)

The file format is detected automatically. If NULL is returned, then error will be set.

Since: 2.26

## newFromResourceAtScale

Arguments

 :: (HasCallStack, MonadIO m) => Text resourcePath: the path of the resource file -> Int32 width: The width the image should have or -1 to not constrain the width -> Int32 height: The height the image should have or -1 to not constrain the height -> Bool preserveAspectRatio: TRUE to preserve the image's aspect ratio -> m (Maybe Pixbuf) Returns: A newly-created pixbuf (Can throw GError)

The file format is detected automatically. If NULL is returned, then error will be set.

The image will be scaled to fit in the requested size, optionally preserving the image's aspect ratio. When preserving the aspect ratio, a width of -1 will cause the image to be scaled to the exact given height, and a height of -1 will cause the image to be scaled to the exact given width. When not preserving aspect ratio, a width or height of -1 means to not scale the image at all in that dimension.

The stream is not closed.

Since: 2.26

## newFromStream

Arguments

 :: (HasCallStack, MonadIO m, IsInputStream a, IsCancellable b) => a stream: a GInputStream to load the pixbuf from -> Maybe b cancellable: optional GCancellable object, NULL to ignore -> m (Maybe Pixbuf) Returns: A newly-created pixbuf (Can throw GError)

Creates a new pixbuf by loading an image from an input stream.

The file format is detected automatically.

If NULL is returned, then error will be set.

The cancellable can be used to abort the operation from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned. Other possible errors are in the GDK_PIXBUF_ERROR and G_IO_ERROR domains.

The stream is not closed.

Since: 2.14

## newFromStreamAsync

Arguments

 :: (HasCallStack, MonadIO m, IsInputStream a, IsCancellable b) => a stream: a GInputStream from which to load the pixbuf -> Maybe b cancellable: optional GCancellable object, NULL to ignore -> Maybe AsyncReadyCallback callback: a GAsyncReadyCallback to call when the pixbuf is loaded -> m ()

Creates a new pixbuf by asynchronously loading an image from an input stream.

For more details see pixbufNewFromStream, which is the synchronous version of this function.

When the operation is finished, callback will be called in the main thread. You can then call pixbufNewFromStreamFinish to get the result of the operation.

Since: 2.24

## newFromStreamAtScale

Arguments

 :: (HasCallStack, MonadIO m, IsInputStream a, IsCancellable b) => a stream: a GInputStream to load the pixbuf from -> Int32 width: The width the image should have or -1 to not constrain the width -> Int32 height: The height the image should have or -1 to not constrain the height -> Bool preserveAspectRatio: TRUE to preserve the image's aspect ratio -> Maybe b cancellable: optional GCancellable object, NULL to ignore -> m (Maybe Pixbuf) Returns: A newly-created pixbuf (Can throw GError)

Creates a new pixbuf by loading an image from an input stream.

The file format is detected automatically. If NULL is returned, then error will be set. The cancellable can be used to abort the operation from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned. Other possible errors are in the GDK_PIXBUF_ERROR and G_IO_ERROR domains.

The image will be scaled to fit in the requested size, optionally preserving the image's aspect ratio.

When preserving the aspect ratio, a width of -1 will cause the image to be scaled to the exact given height, and a height of -1 will cause the image to be scaled to the exact given width. If both width and height are given, this function will behave as if the smaller of the two values is passed as -1.

When not preserving aspect ratio, a width or height of -1 means to not scale the image at all in that dimension.

The stream is not closed.

Since: 2.14

## newFromStreamAtScaleAsync

Arguments

 :: (HasCallStack, MonadIO m, IsInputStream a, IsCancellable b) => a stream: a GInputStream from which to load the pixbuf -> Int32 width: the width the image should have or -1 to not constrain the width -> Int32 height: the height the image should have or -1 to not constrain the height -> Bool preserveAspectRatio: TRUE to preserve the image's aspect ratio -> Maybe b cancellable: optional GCancellable object, NULL to ignore -> Maybe AsyncReadyCallback callback: a GAsyncReadyCallback to call when the pixbuf is loaded -> m ()

Creates a new pixbuf by asynchronously loading an image from an input stream.

For more details see pixbufNewFromStreamAtScale, which is the synchronous version of this function.

When the operation is finished, callback will be called in the main thread. You can then call pixbufNewFromStreamFinish to get the result of the operation.

Since: 2.24

## newFromStreamFinish

Arguments

 :: (HasCallStack, MonadIO m, IsAsyncResult a) => a asyncResult: a GAsyncResult -> m (Maybe Pixbuf) Returns: the newly created pixbuf (Can throw GError)

Finishes an asynchronous pixbuf creation operation started with pixbufNewFromStreamAsync.

Since: 2.24

## newFromXpmData

Arguments

 :: (HasCallStack, MonadIO m) => [Text] data: Pointer to inline XPM data. -> m Pixbuf Returns: A newly-created pixbuf

Creates a new pixbuf by parsing XPM data in memory.

This data is commonly the result of including an XPM file into a program's C source.

## newSubpixbuf

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a srcPixbuf: a GdkPixbuf -> Int32 srcX: X coord in srcPixbuf -> Int32 srcY: Y coord in srcPixbuf -> Int32 width: width of region in srcPixbuf -> Int32 height: height of region in srcPixbuf -> m Pixbuf Returns: a new pixbuf

Creates a new pixbuf which represents a sub-region of src_pixbuf.

The new pixbuf shares its pixels with the original pixbuf, so writing to one affects both. The new pixbuf holds a reference to src_pixbuf, so src_pixbuf will not be finalized until the new pixbuf is finalized.

Note that if src_pixbuf is read-only, this function will force it to be mutable.

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf -> m Bytes Returns: A new reference to a read-only copy of the pixel data. Note that for mutable pixbufs, this function will incur a one-time copy of the pixel data for conversion into the returned Bytes.

Provides a Bytes buffer containing the raw pixel data; the data must not be modified.

This function allows skipping the implicit copy that must be made if gdk_pixbuf_get_pixels() is called on a read-only pixbuf.

Since: 2.32

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: A pixbuf -> m Word8 Returns: a read-only pointer to the raw pixel data

Provides a read-only pointer to the raw pixel data.

This function allows skipping the implicit copy that must be made if gdk_pixbuf_get_pixels() is called on a read-only pixbuf.

Since: 2.32

## removeOption

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: a GdkPixbuf -> Text key: a nul-terminated string representing the key to remove. -> m Bool Returns: TRUE if an option was removed, FALSE if not.

Removes the key/value pair option attached to a GdkPixbuf.

Since: 2.36

## rotateSimple

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a src: a Pixbuf -> PixbufRotation angle: the angle to rotate by -> m (Maybe Pixbuf) Returns: the new pixbuf

Rotates a pixbuf by a multiple of 90 degrees, and returns the result in a new pixbuf.

If angle is 0, this function will return a copy of src.

Since: 2.6

## saturateAndPixelate

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsPixbuf b) => a src: source image -> b dest: place to write modified version of src -> Float saturation: saturation factor -> Bool pixelate: whether to pixelate -> m ()

Modifies saturation and optionally pixelates src, placing the result in dest.

The src and dest pixbufs must have the same image format, size, and rowstride.

The src and dest arguments may be the same pixbuf with no ill effects.

If saturation is 1.0 then saturation is not changed. If it's less than 1.0, saturation is reduced (the image turns toward grayscale); if greater than 1.0, saturation is increased (the image gets more vivid colors).

If pixelate is TRUE, then pixels are faded in a checkerboard pattern to create a pixelated image.

## saveToBufferv

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: a GdkPixbuf. -> Text type: name of file format. -> Maybe [Text] optionKeys: name of options to set -> Maybe [Text] optionValues: values for named options -> m ByteString (Can throw GError)

Vector version of gdk_pixbuf_save_to_buffer().

Saves pixbuf to a new buffer in format type, which is currently "jpeg", "tiff", "png", "ico" or "bmp".

See [methodgdkPixbuf.Pixbuf.save_to_buffer] for more details.

Since: 2.4

## saveToCallbackv

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: a GdkPixbuf. -> PixbufSaveFunc saveFunc: a function that is called to save each block of data that the save routine generates. -> Text type: name of file format. -> Maybe [Text] optionKeys: name of options to set -> Maybe [Text] optionValues: values for named options -> m () (Can throw GError)

Vector version of gdk_pixbuf_save_to_callback().

Saves pixbuf to a callback in format type, which is currently "jpeg", "png", "tiff", "ico" or "bmp".

If error is set, FALSE will be returned.

See [methodgdkPixbuf.Pixbuf.save_to_callback] for more details.

Since: 2.4

## saveToStreamFinish

Arguments

 :: (HasCallStack, MonadIO m, IsAsyncResult a) => a asyncResult: a GAsyncResult -> m () (Can throw GError)

Finishes an asynchronous pixbuf save operation started with gdk_pixbuf_save_to_stream_async().

Since: 2.24

## saveToStreamv

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsOutputStream b, IsCancellable c) => a pixbuf: a GdkPixbuf -> b stream: a GOutputStream to save the pixbuf to -> Text type: name of file format -> Maybe [Text] optionKeys: name of options to set -> Maybe [Text] optionValues: values for named options -> Maybe c cancellable: optional GCancellable object, NULL to ignore -> m () (Can throw GError)

Saves pixbuf to an output stream.

Supported file formats are currently "jpeg", "tiff", "png", "ico" or "bmp".

See [methodgdkPixbuf.Pixbuf.save_to_stream] for more details.

Since: 2.36

## saveToStreamvAsync

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsOutputStream b, IsCancellable c) => a pixbuf: a GdkPixbuf -> b stream: a GOutputStream to which to save the pixbuf -> Text type: name of file format -> Maybe [Text] optionKeys: name of options to set -> Maybe [Text] optionValues: values for named options -> Maybe c cancellable: optional GCancellable object, NULL to ignore -> Maybe AsyncReadyCallback callback: a GAsyncReadyCallback to call when the pixbuf is saved -> m ()

Saves pixbuf to an output stream asynchronously.

For more details see pixbufSaveToStreamv, which is the synchronous version of this function.

When the operation is finished, callback will be called in the main thread.

You can then call pixbufSaveToStreamFinish to get the result of the operation.

Since: 2.36

## savev

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: a GdkPixbuf. -> [Char] filename: name of file to save. -> Text type: name of file format. -> Maybe [Text] optionKeys: name of options to set -> Maybe [Text] optionValues: values for named options -> m () (Can throw GError)

Vector version of gdk_pixbuf_save().

Saves pixbuf to a file in type, which is currently "jpeg", "png", "tiff", "ico" or "bmp".

If error is set, FALSE will be returned.

See [methodgdkPixbuf.Pixbuf.save] for more details.

## scale

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a, IsPixbuf b) => a src: a Pixbuf -> b dest: the Pixbuf into which to render the results -> Int32 destX: the left coordinate for region to render -> Int32 destY: the top coordinate for region to render -> Int32 destWidth: the width of the region to render -> Int32 destHeight: the height of the region to render -> Double offsetX: the offset in the X direction (currently rounded to an integer) -> Double offsetY: the offset in the Y direction (currently rounded to an integer) -> Double scaleX: the scale factor in the X direction -> Double scaleY: the scale factor in the Y direction -> InterpType interpType: the interpolation type for the transformation. -> m ()

Creates a transformation of the source image src by scaling by scaleX and scaleY then translating by offsetX and offsetY, then renders the rectangle (destX, destY, destWidth, destHeight) of the resulting image onto the destination image replacing the previous contents.

Try to use pixbufScaleSimple first; this function is the industrial-strength power tool you can fall back to, if pixbufScaleSimple isn't powerful enough.

If the source rectangle overlaps the destination rectangle on the same pixbuf, it will be overwritten during the scaling which results in rendering artifacts.

## scaleSimple

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a src: a Pixbuf -> Int32 destWidth: the width of destination image -> Int32 destHeight: the height of destination image -> InterpType interpType: the interpolation type for the transformation. -> m (Maybe Pixbuf) Returns: the new pixbuf

Create a new pixbuf containing a copy of src scaled to dest_width x dest_height.

This function leaves src unaffected.

The interp_type should be GDK_INTERP_NEAREST if you want maximum speed (but when scaling down GDK_INTERP_NEAREST is usually unusably ugly). The default interp_type should be GDK_INTERP_BILINEAR which offers reasonable quality and speed.

You can scale a sub-portion of src by creating a sub-pixbuf pointing into src; see [methodgdkPixbuf.Pixbuf.new_subpixbuf].

If dest_width and dest_height are equal to the width and height of src, this function will return an unscaled copy of src.

For more complicated scaling/alpha blending see [methodgdkPixbuf.Pixbuf.scale] and [methodgdkPixbuf.Pixbuf.composite].

## setOption

Arguments

 :: (HasCallStack, MonadIO m, IsPixbuf a) => a pixbuf: a GdkPixbuf -> Text key: a nul-terminated string. -> Text value: a nul-terminated string. -> m Bool Returns: TRUE on success

Attaches a key/value pair as an option to a GdkPixbuf.

If key already exists in the list of options attached to the pixbuf, the new value is ignored and FALSE is returned.

Since: 2.2

# Properties

## bitsPerSample

The number of bits per sample.

Currently only 8 bit per sample are supported.

constructPixbufBitsPerSample :: (IsPixbuf o, MonadIO m) => Int32 -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “bits-per-sample” property. This is rarely needed directly, but it is used by new.

getPixbufBitsPerSample :: (MonadIO m, IsPixbuf o) => o -> m Int32 Source #

Get the value of the “bits-per-sample” property. When overloading is enabled, this is equivalent to

get pixbuf #bitsPerSample


## colorspace

The color space of the pixbuf.

Currently, only GDK_COLORSPACE_RGB is supported.

constructPixbufColorspace :: (IsPixbuf o, MonadIO m) => Colorspace -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “colorspace” property. This is rarely needed directly, but it is used by new.

getPixbufColorspace :: (MonadIO m, IsPixbuf o) => o -> m Colorspace Source #

Get the value of the “colorspace” property. When overloading is enabled, this is equivalent to

get pixbuf #colorspace


## hasAlpha

Whether the pixbuf has an alpha channel.

constructPixbufHasAlpha :: (IsPixbuf o, MonadIO m) => Bool -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “has-alpha” property. This is rarely needed directly, but it is used by new.

getPixbufHasAlpha :: (MonadIO m, IsPixbuf o) => o -> m Bool Source #

Get the value of the “has-alpha” property. When overloading is enabled, this is equivalent to

get pixbuf #hasAlpha


## height

The number of rows of the pixbuf.

constructPixbufHeight :: (IsPixbuf o, MonadIO m) => Int32 -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “height” property. This is rarely needed directly, but it is used by new.

getPixbufHeight :: (MonadIO m, IsPixbuf o) => o -> m Int32 Source #

Get the value of the “height” property. When overloading is enabled, this is equivalent to

get pixbuf #height


## nChannels

The number of samples per pixel.

Currently, only 3 or 4 samples per pixel are supported.

constructPixbufNChannels :: (IsPixbuf o, MonadIO m) => Int32 -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “n-channels” property. This is rarely needed directly, but it is used by new.

getPixbufNChannels :: (MonadIO m, IsPixbuf o) => o -> m Int32 Source #

Get the value of the “n-channels” property. When overloading is enabled, this is equivalent to

get pixbuf #nChannels


## pixelBytes

No description available in the introspection data.

constructPixbufPixelBytes :: (IsPixbuf o, MonadIO m) => Bytes -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “pixel-bytes” property. This is rarely needed directly, but it is used by new.

getPixbufPixelBytes :: (MonadIO m, IsPixbuf o) => o -> m (Maybe Bytes) Source #

Get the value of the “pixel-bytes” property. When overloading is enabled, this is equivalent to

get pixbuf #pixelBytes


## pixels

A pointer to the pixel data of the pixbuf.

constructPixbufPixels :: (IsPixbuf o, MonadIO m) => Ptr () -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “pixels” property. This is rarely needed directly, but it is used by new.

getPixbufPixels :: (MonadIO m, IsPixbuf o) => o -> m (Ptr ()) Source #

Get the value of the “pixels” property. When overloading is enabled, this is equivalent to

get pixbuf #pixels


## rowstride

The number of bytes between the start of a row and the start of the next row.

This number must (obviously) be at least as large as the width of the pixbuf.

constructPixbufRowstride :: (IsPixbuf o, MonadIO m) => Int32 -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “rowstride” property. This is rarely needed directly, but it is used by new.

getPixbufRowstride :: (MonadIO m, IsPixbuf o) => o -> m Int32 Source #

Get the value of the “rowstride” property. When overloading is enabled, this is equivalent to

get pixbuf #rowstride


## width

The number of columns of the pixbuf.

constructPixbufWidth :: (IsPixbuf o, MonadIO m) => Int32 -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “width” property. This is rarely needed directly, but it is used by new.

getPixbufWidth :: (MonadIO m, IsPixbuf o) => o -> m Int32 Source #

Get the value of the “width” property. When overloading is enabled, this is equivalent to

get pixbuf #width
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