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GdkPixbuf-2.0.gir
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GdkPixbuf-2.0.gir
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<?xml version="1.0"?>
<!-- This file was automatically generated from C sources - DO NOT EDIT!
To affect the contents of this file, edit the original C definitions,
and/or use gtk-doc annotations. -->
<repository xmlns="http://www.gtk.org/introspection/core/1.0" xmlns:c="http://www.gtk.org/introspection/c/1.0" xmlns:glib="http://www.gtk.org/introspection/glib/1.0" version="1.2">
<include name="GModule" version="2.0"/>
<include name="Gio" version="2.0"/>
<package name="gdk-pixbuf-2.0"/>
<c:include name="gdk-pixbuf/gdk-pixbuf.h"/>
<namespace name="GdkPixbuf" version="2.0" shared-library="libgdk_pixbuf-2.0.so.0" c:identifier-prefixes="Gdk" c:symbol-prefixes="gdk">
<enumeration name="Colorspace" glib:type-name="GdkColorspace" glib:get-type="gdk_colorspace_get_type" c:type="GdkColorspace">
<doc xml:space="preserve">This enumeration defines the color spaces that are supported by
the gdk-pixbuf library.
Currently only RGB is supported.</doc>
<member name="rgb" value="0" c:identifier="GDK_COLORSPACE_RGB" glib:nick="rgb" glib:name="GDK_COLORSPACE_RGB">
<doc xml:space="preserve">Indicates a red/green/blue additive color space.</doc>
</member>
</enumeration>
<function-macro name="IS_PIXBUF" c:identifier="GDK_IS_PIXBUF" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_ANIMATION" c:identifier="GDK_IS_PIXBUF_ANIMATION" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_ANIMATION_CLASS" c:identifier="GDK_IS_PIXBUF_ANIMATION_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_ANIMATION_ITER" c:identifier="GDK_IS_PIXBUF_ANIMATION_ITER" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_ANIMATION_ITER_CLASS" c:identifier="GDK_IS_PIXBUF_ANIMATION_ITER_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_LOADER" c:identifier="GDK_IS_PIXBUF_LOADER" introspectable="0">
<parameters>
<parameter name="obj">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_LOADER_CLASS" c:identifier="GDK_IS_PIXBUF_LOADER_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_SIMPLE_ANIM" c:identifier="GDK_IS_PIXBUF_SIMPLE_ANIM" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="IS_PIXBUF_SIMPLE_ANIM_CLASS" c:identifier="GDK_IS_PIXBUF_SIMPLE_ANIM_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<enumeration name="InterpType" glib:type-name="GdkInterpType" glib:get-type="gdk_interp_type_get_type" c:type="GdkInterpType">
<doc xml:space="preserve">Interpolation modes for scaling functions.
The `GDK_INTERP_NEAREST` mode is the fastest scaling method, but has
horrible quality when scaling down; `GDK_INTERP_BILINEAR` is the best
choice if you aren't sure what to choose, it has a good speed/quality
balance.
**Note**: Cubic filtering is missing from the list; hyperbolic
interpolation is just as fast and results in higher quality.</doc>
<member name="nearest" value="0" c:identifier="GDK_INTERP_NEAREST" glib:nick="nearest" glib:name="GDK_INTERP_NEAREST">
<doc xml:space="preserve">Nearest neighbor sampling; this is the fastest
and lowest quality mode. Quality is normally unacceptable when scaling
down, but may be OK when scaling up.</doc>
</member>
<member name="tiles" value="1" c:identifier="GDK_INTERP_TILES" glib:nick="tiles" glib:name="GDK_INTERP_TILES">
<doc xml:space="preserve">This is an accurate simulation of the PostScript
image operator without any interpolation enabled. Each pixel is
rendered as a tiny parallelogram of solid color, the edges of which
are implemented with antialiasing. It resembles nearest neighbor for
enlargement, and bilinear for reduction.</doc>
</member>
<member name="bilinear" value="2" c:identifier="GDK_INTERP_BILINEAR" glib:nick="bilinear" glib:name="GDK_INTERP_BILINEAR">
<doc xml:space="preserve">Best quality/speed balance; use this mode by
default. Bilinear interpolation. For enlargement, it is
equivalent to point-sampling the ideal bilinear-interpolated image.
For reduction, it is equivalent to laying down small tiles and
integrating over the coverage area.</doc>
</member>
<member name="hyper" value="3" c:identifier="GDK_INTERP_HYPER" glib:nick="hyper" glib:name="GDK_INTERP_HYPER">
<doc xml:space="preserve">This is the slowest and highest quality
reconstruction function. It is derived from the hyperbolic filters in
Wolberg's "Digital Image Warping", and is formally defined as the
hyperbolic-filter sampling the ideal hyperbolic-filter interpolated
image (the filter is designed to be idempotent for 1:1 pixel mapping).
**Deprecated**: this interpolation filter is deprecated, as in reality
it has a lower quality than the @GDK_INTERP_BILINEAR filter
(Since: 2.38)</doc>
</member>
</enumeration>
<function-macro name="PIXBUF" c:identifier="GDK_PIXBUF" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_ANIMATION" c:identifier="GDK_PIXBUF_ANIMATION" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_ANIMATION_CLASS" c:identifier="GDK_PIXBUF_ANIMATION_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_ANIMATION_GET_CLASS" c:identifier="GDK_PIXBUF_ANIMATION_GET_CLASS" introspectable="0">
<parameters>
<parameter name="obj">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_ANIMATION_ITER" c:identifier="GDK_PIXBUF_ANIMATION_ITER" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_ANIMATION_ITER_CLASS" c:identifier="GDK_PIXBUF_ANIMATION_ITER_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_ANIMATION_ITER_GET_CLASS" c:identifier="GDK_PIXBUF_ANIMATION_ITER_GET_CLASS" introspectable="0">
<parameters>
<parameter name="obj">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_CHECK_VERSION" c:identifier="GDK_PIXBUF_CHECK_VERSION" version="2.36" introspectable="0">
<doc xml:space="preserve">Macro to test the version of GdkPixbuf being compiled against.</doc>
<parameters>
<parameter name="major">
<doc xml:space="preserve">major version (e.g. 2 for version 2.34.0)</doc>
</parameter>
<parameter name="minor">
<doc xml:space="preserve">minor version (e.g. 34 for version 2.34.0)</doc>
</parameter>
<parameter name="micro">
<doc xml:space="preserve">micro version (e.g. 0 for version 2.34.0)</doc>
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_0_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_0_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_10_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_10_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_12_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_12_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_14_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_14_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_16_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_16_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_18_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_18_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_20_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_20_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_22_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_22_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_24_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_24_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_26_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_26_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_28_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_28_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_2_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_2_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_30_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_30_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_32_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_32_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_34_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_34_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_36_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_36_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_38_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_38_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_40_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_40_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_4_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_4_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_6_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_6_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_DEPRECATED_IN_2_8_FOR" c:identifier="GDK_PIXBUF_DEPRECATED_IN_2_8_FOR" introspectable="0">
<parameters>
<parameter name="f">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_LOADER" c:identifier="GDK_PIXBUF_LOADER" introspectable="0">
<parameters>
<parameter name="obj">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_LOADER_CLASS" c:identifier="GDK_PIXBUF_LOADER_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_LOADER_GET_CLASS" c:identifier="GDK_PIXBUF_LOADER_GET_CLASS" introspectable="0">
<parameters>
<parameter name="obj">
</parameter>
</parameters>
</function-macro>
<constant name="PIXBUF_MAJOR" value="2" c:type="GDK_PIXBUF_MAJOR">
<doc xml:space="preserve">Major version of gdk-pixbuf library, that is the "0" in
"0.8.2" for example.</doc>
<type name="gint" c:type="gint"/>
</constant>
<constant name="PIXBUF_MICRO" value="11" c:type="GDK_PIXBUF_MICRO">
<doc xml:space="preserve">Micro version of gdk-pixbuf library, that is the "2" in
"0.8.2" for example.</doc>
<type name="gint" c:type="gint"/>
</constant>
<constant name="PIXBUF_MINOR" value="42" c:type="GDK_PIXBUF_MINOR">
<doc xml:space="preserve">Minor version of gdk-pixbuf library, that is the "8" in
"0.8.2" for example.</doc>
<type name="gint" c:type="gint"/>
</constant>
<function-macro name="PIXBUF_SIMPLE_ANIM" c:identifier="GDK_PIXBUF_SIMPLE_ANIM" introspectable="0">
<parameters>
<parameter name="object">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_SIMPLE_ANIM_CLASS" c:identifier="GDK_PIXBUF_SIMPLE_ANIM_CLASS" introspectable="0">
<parameters>
<parameter name="klass">
</parameter>
</parameters>
</function-macro>
<function-macro name="PIXBUF_SIMPLE_ANIM_GET_CLASS" c:identifier="GDK_PIXBUF_SIMPLE_ANIM_GET_CLASS" introspectable="0">
<parameters>
<parameter name="obj">
</parameter>
</parameters>
</function-macro>
<constant name="PIXBUF_VERSION" value="2.42.11" c:type="GDK_PIXBUF_VERSION">
<doc xml:space="preserve">Contains the full version of GdkPixbuf as a string.
This is the version being compiled against; contrast with
`gdk_pixbuf_version`.</doc>
<type name="utf8" c:type="gchar*"/>
</constant>
<class name="Pixbuf" c:symbol-prefix="pixbuf" c:type="GdkPixbuf" parent="GObject.Object" glib:type-name="GdkPixbuf" glib:get-type="gdk_pixbuf_get_type">
<doc xml:space="preserve">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 [[email protected]] instance. You can use the
[`[email protected]_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 [`[email protected]`] 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 [`[email protected]_from_xpm_data`]
function to create a pixbuf from inline XPM image data.
You can also copy an existing pixbuf with the [[email protected]]
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 [class@Pixbuf] 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 [`[email protected]_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
[[email protected]] 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;
}
```
## Loading images
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 [[email protected]`]
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.</doc>
<implements name="Gio.Icon"/>
<implements name="Gio.LoadableIcon"/>
<constructor name="new" c:identifier="gdk_pixbuf_new">
<doc xml:space="preserve">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.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixel buffer</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="colorspace" transfer-ownership="none">
<doc xml:space="preserve">Color space for image</doc>
<type name="Colorspace" c:type="GdkColorspace"/>
</parameter>
<parameter name="has_alpha" transfer-ownership="none">
<doc xml:space="preserve">Whether the image should have transparency information</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
<parameter name="bits_per_sample" transfer-ownership="none">
<doc xml:space="preserve">Number of bits per color sample</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">Width of image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">Height of image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_bytes" c:identifier="gdk_pixbuf_new_from_bytes" version="2.32">
<doc xml:space="preserve">Creates a new #GdkPixbuf out of in-memory readonly image data.
Currently only RGB images with 8 bits per sample are supported.
This is the `GBytes` variant of gdk_pixbuf_new_from_data(), useful
for language bindings.</doc>
<return-value transfer-ownership="full">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="data" transfer-ownership="none">
<doc xml:space="preserve">Image data in 8-bit/sample packed format inside a #GBytes</doc>
<type name="GLib.Bytes" c:type="GBytes*"/>
</parameter>
<parameter name="colorspace" transfer-ownership="none">
<doc xml:space="preserve">Colorspace for the image data</doc>
<type name="Colorspace" c:type="GdkColorspace"/>
</parameter>
<parameter name="has_alpha" transfer-ownership="none">
<doc xml:space="preserve">Whether the data has an opacity channel</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
<parameter name="bits_per_sample" transfer-ownership="none">
<doc xml:space="preserve">Number of bits per sample</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">Width of the image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">Height of the image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="rowstride" transfer-ownership="none">
<doc xml:space="preserve">Distance in bytes between row starts</doc>
<type name="gint" c:type="int"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_data" c:identifier="gdk_pixbuf_new_from_data">
<doc xml:space="preserve">Creates a new #GdkPixbuf 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: [[email protected]_from_bytes]</doc>
<return-value transfer-ownership="full">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="data" transfer-ownership="none">
<doc xml:space="preserve">Image data in 8-bit/sample packed format</doc>
<array zero-terminated="0" c:type="const guchar*">
<type name="guint8" c:type="guchar"/>
</array>
</parameter>
<parameter name="colorspace" transfer-ownership="none">
<doc xml:space="preserve">Colorspace for the image data</doc>
<type name="Colorspace" c:type="GdkColorspace"/>
</parameter>
<parameter name="has_alpha" transfer-ownership="none">
<doc xml:space="preserve">Whether the data has an opacity channel</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
<parameter name="bits_per_sample" transfer-ownership="none">
<doc xml:space="preserve">Number of bits per sample</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">Width of the image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">Height of the image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="rowstride" transfer-ownership="none">
<doc xml:space="preserve">Distance in bytes between row starts</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="destroy_fn" transfer-ownership="none" nullable="1" allow-none="1" scope="async" closure="8">
<doc xml:space="preserve">Function used to free the data when the pixbuf's reference count
drops to zero, or %NULL if the data should not be freed</doc>
<type name="PixbufDestroyNotify" c:type="GdkPixbufDestroyNotify"/>
</parameter>
<parameter name="destroy_fn_data" transfer-ownership="none" nullable="1" allow-none="1">
<doc xml:space="preserve">Closure data to pass to the destroy notification function</doc>
<type name="gpointer" c:type="gpointer"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_file" c:identifier="gdk_pixbuf_new_from_file" throws="1">
<doc xml:space="preserve">Creates a new pixbuf by loading an image from a file.
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`.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="filename" transfer-ownership="none">
<doc xml:space="preserve">Name of file to load, in the GLib file
name encoding</doc>
<type name="filename" c:type="const char*"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_file_at_scale" c:identifier="gdk_pixbuf_new_from_file_at_scale" version="2.6" throws="1">
<doc xml:space="preserve">Creates a new pixbuf by loading an image from a file.
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.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="filename" transfer-ownership="none">
<doc xml:space="preserve">Name of file to load, in the GLib file
name encoding</doc>
<type name="filename" c:type="const char*"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">The width the image should have or -1 to not constrain the width</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">The height the image should have or -1 to not constrain the height</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="preserve_aspect_ratio" transfer-ownership="none">
<doc xml:space="preserve">`TRUE` to preserve the image's aspect ratio</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_file_at_size" c:identifier="gdk_pixbuf_new_from_file_at_size" version="2.4" throws="1">
<doc xml:space="preserve">Creates a new pixbuf by loading an image from a file.
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
[[email protected]_from_file_at_scale].</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="filename" transfer-ownership="none">
<doc xml:space="preserve">Name of file to load, in the GLib file
name encoding</doc>
<type name="filename" c:type="const char*"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">The width the image should have or -1 to not constrain the width</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">The height the image should have or -1 to not constrain the height</doc>
<type name="gint" c:type="int"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_inline" c:identifier="gdk_pixbuf_new_from_inline" deprecated="1" deprecated-version="2.32" throws="1">
<doc xml:space="preserve">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 `GdkPixbuf`s 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.</doc>
<doc-deprecated xml:space="preserve">Use `GResource` instead.</doc-deprecated>
<return-value transfer-ownership="full">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="data_length" transfer-ownership="none">
<doc xml:space="preserve">Length in bytes of the `data` argument or -1 to
disable length checks</doc>
<type name="gint" c:type="gint"/>
</parameter>
<parameter name="data" transfer-ownership="none">
<doc xml:space="preserve">Byte data containing a
serialized `GdkPixdata` structure</doc>
<array length="0" zero-terminated="0" c:type="const guint8*">
<type name="guint8" c:type="guint8"/>
</array>
</parameter>
<parameter name="copy_pixels" transfer-ownership="none">
<doc xml:space="preserve">Whether to copy the pixel data, or use direct pointers
`data` for the resulting pixbuf</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_resource" c:identifier="gdk_pixbuf_new_from_resource" version="2.26" throws="1">
<doc xml:space="preserve">Creates a new pixbuf by loading an image from an resource.
The file format is detected automatically. If `NULL` is returned, then
@error will be set.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="resource_path" transfer-ownership="none">
<doc xml:space="preserve">the path of the resource file</doc>
<type name="utf8" c:type="const char*"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_resource_at_scale" c:identifier="gdk_pixbuf_new_from_resource_at_scale" version="2.26" throws="1">
<doc xml:space="preserve">Creates a new pixbuf by loading an image from an resource.
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.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="resource_path" transfer-ownership="none">
<doc xml:space="preserve">the path of the resource file</doc>
<type name="utf8" c:type="const char*"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">The width the image should have or -1 to not constrain the width</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">The height the image should have or -1 to not constrain the height</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="preserve_aspect_ratio" transfer-ownership="none">
<doc xml:space="preserve">`TRUE` to preserve the image's aspect ratio</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_stream" c:identifier="gdk_pixbuf_new_from_stream" version="2.14" throws="1">
<doc xml:space="preserve">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.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="stream" transfer-ownership="none">
<doc xml:space="preserve">a `GInputStream` to load the pixbuf from</doc>
<type name="Gio.InputStream" c:type="GInputStream*"/>
</parameter>
<parameter name="cancellable" transfer-ownership="none" nullable="1" allow-none="1">
<doc xml:space="preserve">optional `GCancellable` object, `NULL` to ignore</doc>
<type name="Gio.Cancellable" c:type="GCancellable*"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_stream_at_scale" c:identifier="gdk_pixbuf_new_from_stream_at_scale" version="2.14" throws="1">
<doc xml:space="preserve">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.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="stream" transfer-ownership="none">
<doc xml:space="preserve">a `GInputStream` to load the pixbuf from</doc>
<type name="Gio.InputStream" c:type="GInputStream*"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">The width the image should have or -1 to not constrain the width</doc>
<type name="gint" c:type="gint"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">The height the image should have or -1 to not constrain the height</doc>
<type name="gint" c:type="gint"/>
</parameter>
<parameter name="preserve_aspect_ratio" transfer-ownership="none">
<doc xml:space="preserve">`TRUE` to preserve the image's aspect ratio</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
<parameter name="cancellable" transfer-ownership="none" nullable="1" allow-none="1">
<doc xml:space="preserve">optional `GCancellable` object, `NULL` to ignore</doc>
<type name="Gio.Cancellable" c:type="GCancellable*"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_stream_finish" c:identifier="gdk_pixbuf_new_from_stream_finish" version="2.24" throws="1">
<doc xml:space="preserve">Finishes an asynchronous pixbuf creation operation started with
gdk_pixbuf_new_from_stream_async().</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">the newly created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="async_result" transfer-ownership="none">
<doc xml:space="preserve">a `GAsyncResult`</doc>
<type name="Gio.AsyncResult" c:type="GAsyncResult*"/>
</parameter>
</parameters>
</constructor>
<constructor name="new_from_xpm_data" c:identifier="gdk_pixbuf_new_from_xpm_data">
<doc xml:space="preserve">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.</doc>
<return-value transfer-ownership="full" nullable="1">
<doc xml:space="preserve">A newly-created pixbuf</doc>
<type name="Pixbuf" c:type="GdkPixbuf*"/>
</return-value>
<parameters>
<parameter name="data" transfer-ownership="none">
<doc xml:space="preserve">Pointer to inline XPM data.</doc>
<array c:type="const char**">
<type name="utf8" c:type="char*"/>
</array>
</parameter>
</parameters>
</constructor>
<function name="calculate_rowstride" c:identifier="gdk_pixbuf_calculate_rowstride" version="2.36.8">
<doc xml:space="preserve">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`.</doc>
<return-value transfer-ownership="none">
<doc xml:space="preserve">the rowstride for the given values, or -1 in case of error.</doc>
<type name="gint" c:type="gint"/>
</return-value>
<parameters>
<parameter name="colorspace" transfer-ownership="none">
<doc xml:space="preserve">Color space for image</doc>
<type name="Colorspace" c:type="GdkColorspace"/>
</parameter>
<parameter name="has_alpha" transfer-ownership="none">
<doc xml:space="preserve">Whether the image should have transparency information</doc>
<type name="gboolean" c:type="gboolean"/>
</parameter>
<parameter name="bits_per_sample" transfer-ownership="none">
<doc xml:space="preserve">Number of bits per color sample</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="width" transfer-ownership="none">
<doc xml:space="preserve">Width of image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
<parameter name="height" transfer-ownership="none">
<doc xml:space="preserve">Height of image in pixels, must be > 0</doc>
<type name="gint" c:type="int"/>
</parameter>
</parameters>
</function>
<function name="get_file_info" c:identifier="gdk_pixbuf_get_file_info" version="2.4">
<doc xml:space="preserve">Parses an image file far enough to determine its format and size.</doc>
<return-value transfer-ownership="none" nullable="1">
<doc xml:space="preserve">A `GdkPixbufFormat` describing
the image format of the file</doc>
<type name="PixbufFormat" c:type="GdkPixbufFormat*"/>
</return-value>
<parameters>
<parameter name="filename" transfer-ownership="none">
<doc xml:space="preserve">The name of the file to identify.</doc>