|  |  |  | GDK-PixBuf Reference Manual |  | 
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| Top | Description | ||||
| Image Data in MemoryImage Data in Memory — Creating a pixbuf from image data that is already in memory. | 
#include <gdk-pixbuf/gdk-pixbuf.h> GdkPixbuf * gdk_pixbuf_new (GdkColorspace colorspace,gboolean has_alpha,int bits_per_sample,int width,int height); GdkPixbuf * gdk_pixbuf_new_from_data (const guchar *data,GdkColorspace colorspace,gboolean has_alpha,int bits_per_sample,int width,int height,int rowstride,GdkPixbufDestroyNotify destroy_fn,gpointer destroy_fn_data); GdkPixbuf * gdk_pixbuf_new_from_xpm_data (const char **data); GdkPixbuf * gdk_pixbuf_new_from_inline (gint data_length,const guint8 *data,gboolean copy_pixels,GError **error); GdkPixbuf * gdk_pixbuf_new_subpixbuf (GdkPixbuf *src_pixbuf,int src_x,int src_y,int width,int height); GdkPixbuf * gdk_pixbuf_copy (const GdkPixbuf *pixbuf);
The most basic way to create a pixbuf is to wrap an existing pixel
buffer with a GdkPixbuf structure.  You can use the
gdk_pixbuf_new_from_data() function to do this You 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 gdk_pixbuf_new() 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()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 gdk_pixbuf_new_from_xpm_data()
function to create a pixbuf from inline XPM image data.
You can also copy an existing pixbuf with the gdk_pixbuf_copy()
function.  This is not the same as just doing a g_object_ref()
on the old pixbuf; the copy function will actually duplicate the
pixel data in memory and create a new GdkPixbuf structure for it.
GdkPixbuf * gdk_pixbuf_new (GdkColorspace colorspace,gboolean has_alpha,int bits_per_sample,int width,int height);
Creates a new GdkPixbuf structure and allocates a buffer for it. The buffer has an optimal rowstride. Note that the buffer is not cleared; you will have to fill it completely yourself.
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 | Color space for image | 
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 | Whether the image should have transparency information | 
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 | Number of bits per color sample | 
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 | Width of image in pixels, must be > 0 | 
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 | Height of image in pixels, must be > 0 | 
| Returns : | A newly-created GdkPixbuf with a reference count of 1, or NULLif not enough memory could be allocated for the image buffer. | 
GdkPixbuf * gdk_pixbuf_new_from_data (const guchar *data,GdkColorspace colorspace,gboolean has_alpha,int bits_per_sample,int width,int height,int rowstride,GdkPixbufDestroyNotify destroy_fn,gpointer destroy_fn_data);
Creates a new GdkPixbuf out of in-memory image data. Currently only RGB images with 8 bits per sample are supported.
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 | Image data in 8-bit/sample packed format. [array] | 
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 | Colorspace for the image data | 
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 | Whether the data has an opacity channel | 
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 | Number of bits per sample | 
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 | Width of the image in pixels, must be > 0 | 
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 | Height of the image in pixels, must be > 0 | 
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 | Distance in bytes between row starts | 
| 
 | Function used to free the data when the pixbuf's reference count
drops to zero, or NULLif the data should not be freed. [scope async][allow-none] | 
| 
 | Closure data to pass to the destroy notification function. [closure] | 
| Returns : | A newly-created GdkPixbuf structure with a reference count of 1. [transfer full] | 
GdkPixbuf *         gdk_pixbuf_new_from_xpm_data        (const char **data);
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.
| 
 | Pointer to inline XPM data. [array zero-terminated=1] | 
| Returns : | A newly-created pixbuf with a reference count of 1. | 
GdkPixbuf * gdk_pixbuf_new_from_inline (gint data_length,const guint8 *data,gboolean copy_pixels,GError **error);
Create 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.
gdk-pixbuf 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 flag to
gdk-pixbuf-csource. A sample invocation would be:
| 1 | 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:
| 1 | 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.
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 | Length in bytes of the dataargument or -1 to
disable length checks | 
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 | Byte data containing a serialized GdkPixdata structure. [array length=data_length] | 
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 | Whether to copy the pixel data, or use direct pointers datafor the resulting pixbuf | 
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 | GError return location, may be NULLto ignore errors | 
| Returns : | A newly-created GdkPixbuf structure with a reference,
count of 1, or NULLif an error occurred. | 
GdkPixbuf * gdk_pixbuf_new_subpixbuf (GdkPixbuf *src_pixbuf,int src_x,int src_y,int width,int height);
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.
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 | a GdkPixbuf | 
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 | X coord in src_pixbuf | 
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 | Y coord in src_pixbuf | 
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 | width of region in src_pixbuf | 
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 | height of region in src_pixbuf | 
| Returns : | a new pixbuf. [transfer full] |