File saving

File saving — Saving a pixbuf to a file.

Synopsis


#include <gdk-pixbuf/gdk-pixbuf.h>

gboolean            gdk_pixbuf_savev                    (GdkPixbuf *pixbuf,
                                                         const char *filename,
                                                         const char *type,
                                                         char **option_keys,
                                                         char **option_values,
                                                         GError **error);
gboolean            gdk_pixbuf_save                     (GdkPixbuf *pixbuf,
                                                         const char *filename,
                                                         const char *type,
                                                         GError **error,
                                                         ...);
gboolean            (*GdkPixbufSaveFunc)                (const gchar *buf,
                                                         gsize count,
                                                         GError **error,
                                                         gpointer data);
gboolean            gdk_pixbuf_save_to_callback         (GdkPixbuf *pixbuf,
                                                         GdkPixbufSaveFunc save_func,
                                                         gpointer user_data,
                                                         const char *type,
                                                         GError **error,
                                                         ...);
gboolean            gdk_pixbuf_save_to_callbackv        (GdkPixbuf *pixbuf,
                                                         GdkPixbufSaveFunc save_func,
                                                         gpointer user_data,
                                                         const char *type,
                                                         char **option_keys,
                                                         char **option_values,
                                                         GError **error);
gboolean            gdk_pixbuf_save_to_buffer           (GdkPixbuf *pixbuf,
                                                         gchar **buffer,
                                                         gsize *buffer_size,
                                                         const char *type,
                                                         GError **error,
                                                         ...);
gboolean            gdk_pixbuf_save_to_bufferv          (GdkPixbuf *pixbuf,
                                                         gchar **buffer,
                                                         gsize *buffer_size,
                                                         const char *type,
                                                         char **option_keys,
                                                         char **option_values,
                                                         GError **error);

Description

These functions allow to save a GdkPixbuf in a number of file formats. The formatted data can be written to a file or to a memory buffer. gdk-pixbuf 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.

Details

gdk_pixbuf_savev ()

gboolean            gdk_pixbuf_savev                    (GdkPixbuf *pixbuf,
                                                         const char *filename,
                                                         const char *type,
                                                         char **option_keys,
                                                         char **option_values,
                                                         GError **error);

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 gdk_pixbuf_save() for more details.

pixbuf : a GdkPixbuf.
filename : name of file to save.
type : name of file format.
option_keys : name of options to set, NULL-terminated
option_values : values for named options
error : return location for error, or NULL
Returns : whether an error was set

gdk_pixbuf_save ()

gboolean            gdk_pixbuf_save                     (GdkPixbuf *pixbuf,
                                                         const char *filename,
                                                         const char *type,
                                                         GError **error,
                                                         ...);

Saves pixbuf to a file in format type. By default, "jpeg", "png", "ico" and "bmp" are possible file formats to save in, but more formats may be installed. The list of all writable formats can be determined in the following way:

void add_if_writable (GdkPixbufFormat *data, GSList **list)
{
  if (gdk_pixbuf_format_is_writable (data))
    *list = g_slist_prepend (*list, data);
}

GSList *formats = gdk_pixbuf_get_formats ();
GSList *writable_formats = NULL;
g_slist_foreach (formats, add_if_writable, &writable_formats);
g_slist_free (formats);

If error is set, FALSE will be returned. Possible errors include those in the GDK_PIXBUF_ERROR domain and those in the G_FILE_ERROR domain.

The variable argument list should be NULL-terminated; if not empty, it should contain pairs of strings that modify the save parameters. For example:

gdk_pixbuf_save (pixbuf, handle, "jpeg", &error,
                 "quality", "100", NULL);

Currently only few parameters exist. JPEG images can be saved with a "quality" parameter; its value should be in the range [0,100].

Text chunks can be attached to PNG images by specifying parameters of the form "tEXt::key", where key is an ASCII string of length 1-79. The values are UTF-8 encoded strings. The PNG compression level can be specified using the "compression" parameter; it's value is in an integer in the range of [0,9].

ICO images can be saved in depth 16, 24, or 32, by using the "depth" parameter. When the ICO saver is given "x_hot" and "y_hot" parameters, it produces a CUR instead of an ICO.

pixbuf : a GdkPixbuf.
filename : name of file to save.
type : name of file format.
error : return location for error, or NULL
... : list of key-value save options
Returns : whether an error was set

GdkPixbufSaveFunc ()

gboolean            (*GdkPixbufSaveFunc)                (const gchar *buf,
                                                         gsize count,
                                                         GError **error,
                                                         gpointer data);

Specifies the type of the function passed to gdk_pixbuf_save_to_callback(). It is called once for each block of bytes that is "written" by gdk_pixbuf_save_to_callback(). If successful it should return TRUE. If an error occurs it should set error and return FALSE, in which case gdk_pixbuf_save_to_callback() will fail with the same error.

buf : bytes to be written.
count : number of bytes in buf.
error : A location to return an error.
data : user data passed to gdk_pixbuf_save_to_callback().
Returns : TRUE if successful, FALSE (with error set) if failed.

Since 2.4


gdk_pixbuf_save_to_callback ()

gboolean            gdk_pixbuf_save_to_callback         (GdkPixbuf *pixbuf,
                                                         GdkPixbufSaveFunc save_func,
                                                         gpointer user_data,
                                                         const char *type,
                                                         GError **error,
                                                         ...);

Saves pixbuf in format type by feeding the produced data to a callback. Can be used when you want to store the image to something other than a file, such as an in-memory buffer or a socket. If error is set, FALSE will be returned. Possible errors include those in the GDK_PIXBUF_ERROR domain and whatever the save function generates.

See gdk_pixbuf_save() for more details.

pixbuf : a GdkPixbuf.
save_func : a function that is called to save each block of data that the save routine generates.
user_data : user data to pass to the save function.
type : name of file format.
error : return location for error, or NULL
... : list of key-value save options
Returns : whether an error was set

Since 2.4


gdk_pixbuf_save_to_callbackv ()

gboolean            gdk_pixbuf_save_to_callbackv        (GdkPixbuf *pixbuf,
                                                         GdkPixbufSaveFunc save_func,
                                                         gpointer user_data,
                                                         const char *type,
                                                         char **option_keys,
                                                         char **option_values,
                                                         GError **error);

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 gdk_pixbuf_save_to_callback() for more details.

pixbuf : a GdkPixbuf.
save_func : a function that is called to save each block of data that the save routine generates.
user_data : user data to pass to the save function.
type : name of file format.
option_keys : name of options to set, NULL-terminated
option_values : values for named options
error : return location for error, or NULL
Returns : whether an error was set

Since 2.4


gdk_pixbuf_save_to_buffer ()

gboolean            gdk_pixbuf_save_to_buffer           (GdkPixbuf *pixbuf,
                                                         gchar **buffer,
                                                         gsize *buffer_size,
                                                         const char *type,
                                                         GError **error,
                                                         ...);

Saves pixbuf to a new buffer in format type, which is currently "jpeg", "png", "tiff", "ico" or "bmp". This is a convenience function that uses gdk_pixbuf_save_to_callback() to do the real work. Note that the buffer is not nul-terminated and may contain embedded nuls. If error is set, FALSE will be returned and string will be set to NULL. Possible errors include those in the GDK_PIXBUF_ERROR domain.

See gdk_pixbuf_save() for more details.

pixbuf : a GdkPixbuf.
buffer : location to receive a pointer to the new buffer.
buffer_size : location to receive the size of the new buffer.
type : name of file format.
error : return location for error, or NULL
... : list of key-value save options
Returns : whether an error was set

Since 2.4


gdk_pixbuf_save_to_bufferv ()

gboolean            gdk_pixbuf_save_to_bufferv          (GdkPixbuf *pixbuf,
                                                         gchar **buffer,
                                                         gsize *buffer_size,
                                                         const char *type,
                                                         char **option_keys,
                                                         char **option_values,
                                                         GError **error);

Saves pixbuf to a new buffer in format type, which is currently "jpeg", "tiff", "png", "ico" or "bmp". See gdk_pixbuf_save_to_buffer() for more details.

pixbuf : a GdkPixbuf.
buffer : location to receive a pointer to the new buffer.
buffer_size : location to receive the size of the new buffer.
type : name of file format.
option_keys : name of options to set, NULL-terminated
option_values : values for named options
error : return location for error, or NULL
Returns : whether an error was set

Since 2.4