Image Data in Memory

## Image Data in Memory Image Data in Memory — Creating a pixbuf from image data that is already in memory. |

## Synopsis

    #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);

## Description

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()`` 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 `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.

## Details

### gdk_pixbuf_new ()

    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.

`colorspace` : | Color space for image
`has_alpha` : | Whether the image should have transparency information
`bits_per_sample` : | Number of bits per color sample
`width` : | Width of image in pixels, must be > 0
`height` : | Height of image in pixels, must be > 0
Returns : | A newly-created GdkPixbuf with a reference count of 1, or `NULL` if not enough memory could be allocated for the image buffer.

### gdk_pixbuf_new_from_data ()

    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.

`data` : | Image data in 8-bit/sample packed format. [array][element-type char]
`colorspace` : | Colorspace for the image data
`has_alpha` : | Whether the data has an opacity channel
`bits_per_sample` : | Number of bits per sample
`width` : | Width of the image in pixels, must be > 0
`height` : | Height of the image in pixels, must be > 0
`rowstride` : | Distance in bytes between row starts
`destroy_fn` : | Function used to free the data when the pixbuf's reference count drops to zero, or `NULL` if the data should not be freed. [scope async]
`destroy_fn_data` : | Closure data to pass to the destroy notification function. [closure]
Returns : | A newly-created GdkPixbuf structure with a reference count of 1. [transfer full]

### gdk_pixbuf_new_from_xpm_data ()

    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.

`data` : | Pointer to inline XPM data.
Returns : | A newly-created pixbuf with a reference count of 1.

### gdk_pixbuf_new_from_inline ()

    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.

`data_length` : | Length in bytes of the `data` argument or -1 to disable length checks
`data` : | Byte data containing a serialized GdkPixdata structure
`copy_pixels` : | Whether to copy the pixel data, or use direct pointers `data` for the resulting pixbuf
`error` : | GError return location, may be `NULL` to ignore errors
Returns : | A newly-created GdkPixbuf structure with a reference, count of 1, or `NULL` if an error occurred.

### gdk_pixbuf_new_subpixbuf ()

    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.

`src_pixbuf` : | a GdkPixbuf
`src_x` : | X coord in `src_pixbuf`
`src_y` : | Y coord in `src_pixbuf`
`width` : | width of region in `src_pixbuf`
`height` : | height of region in `src_pixbuf`
Returns : | a new pixbuf. [transfer full]

### gdk_pixbuf_copy ()

    GdkPixbuf *         gdk_pixbuf_copy                     (const GdkPixbuf *pixbuf);

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

`pixbuf` : | A pixbuf.
Returns : | A newly-created pixbuf with a reference count of 1, or `NULL` if not enough memory could be allocated. [transfer full]

## See Also

gdk_pixbuf_finalize().