GDK 3 Reference Manual: Pixbufs

## Pixbufs Pixbufs — Functions for obtaining pixbufs |

## Functions

GdkPixbuf * | gdk_pixbuf_get_from_window ()
GdkPixbuf * | gdk_pixbuf_get_from_surface ()

## Includes

    #include <gdk/gdk.h>

## Description

Pixbufs are client-side images. For details on how to create and manipulate pixbufs, see the GdkPixbuf API documentation.

The functions described here allow to obtain pixbufs from GdkWindows and cairo surfaces.

## Functions

### gdk_pixbuf_get_from_window ()

    GdkPixbuf *
    gdk_pixbuf_get_from_window (GdkWindow *window,
                                gint src_x,
                                gint src_y,
                                gint width,
                                gint height);

Transfers image data from a GdkWindow and converts it to an RGB(A) representation inside a GdkPixbuf. In other words, copies image data from a server-side drawable to a client-side RGB(A) buffer. This allows you to efficiently read individual pixels on the client side.

This function will create an RGB pixbuf with 8 bits per channel with the same size specified by the `width` and `height` arguments. The pixbuf will contain an alpha channel if the `window` contains one.

If the window is off the screen, then there is no image data in the obscured/offscreen regions to be placed in the pixbuf. The contents of portions of the pixbuf corresponding to the offscreen region are undefined.

If the window you’re obtaining data from is partially obscured by other windows, then the contents of the pixbuf areas corresponding to the obscured regions are undefined.

If the window is not mapped (typically because it’s iconified/minimized or not on the current workspace), then `NULL` will be returned.

If memory can’t be allocated for the return value, `NULL` will be returned instead.

(In short, there are several ways this function can fail, and if it fails it returns `NULL`; so check the return value.)

#### Parameters

window | Source window |
src_x | Source X coordinate within `window` |
src_y | Source Y coordinate within `window` |
width | Width in pixels of region to get |
height | Height in pixels of region to get |

#### Returns

A newly-created pixbuf with a reference count of 1, or `NULL` on error.

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### gdk_pixbuf_get_from_surface ()

    GdkPixbuf *
    gdk_pixbuf_get_from_surface (cairo_surface_t *surface,
                                 gint src_x,
                                 gint src_y,
                                 gint width,
                                 gint height);

Transfers image data from a cairo_surface_t and converts it to an RGB(A) representation inside a GdkPixbuf. This allows you to efficiently read individual pixels from cairo surfaces. For GdkWindows, use `gdk_pixbuf_get_from_window()` instead.

This function will create an RGB pixbuf with 8 bits per channel. The pixbuf will contain an alpha channel if the `surface` contains one.

#### Parameters

surface | surface to copy from |
src_x | Source X coordinate within `surface` |
src_y | Source Y coordinate within `surface` |
width | Width in pixels of region to get |
height | Height in pixels of region to get |

#### Returns

A newly-created pixbuf with a reference count of 1, or `NULL` on error.

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## Types and Values