File saving

File saving — Saving a pixbuf to a file.

Functions

Includes

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

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. 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.

Functions

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.

Parameters

pixbuf

a GdkPixbuf.

 

filename

name of file to save.

 

type

name of file format.

 

option_keys

name of options to set, NULL-terminated.

[array zero-terminated=1]

option_values

values for named options.

[array zero-terminated=1]

error

return location for error, or NULL.

[allow-none]

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:

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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:

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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].

ICC color profiles can also be embedded into PNG, JPEG and TIFF images. The "icc-profile" value should be the complete ICC profile encoded into base64.

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gchar *contents;
gchar *contents_encode;
gsize length;
g_file_get_contents ("/home/hughsie/.color/icc/L225W.icm", &contents, &length, NULL);
contents_encode = g_base64_encode ((const guchar *) contents, length);
gdk_pixbuf_save (pixbuf, handle, "png", &error, "icc-profile", contents_encode, NULL);

TIFF images recognize a "compression" option which acceps an integer value. Among the codecs are 1 None, 2 Huffman, 5 LZW, 7 JPEG and 8 Deflate, see the libtiff documentation and tiff.h for all supported codec values.

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.

Parameters

pixbuf

a GdkPixbuf.

 

filename

name of file to save.

 

type

name of file format.

 

error

return location for error, or NULL.

[allow-none]

...

list of key-value save options, followed by NULL

 

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.

Parameters

buf

bytes to be written.

[array length=count][element-type guint8]

count

number of bytes in buf .

 

error

A location to return an error.

[out]

data

user data passed to gdk_pixbuf_save_to_callback().

[closure]

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.

Parameters

pixbuf

a GdkPixbuf.

 

save_func

a function that is called to save each block of data that the save routine generates.

[scope call]

user_data

user data to pass to the save function.

 

type

name of file format.

 

error

return location for error, or NULL.

[allow-none]

...

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.

Parameters

pixbuf

a GdkPixbuf.

 

save_func

a function that is called to save each block of data that the save routine generates.

[scope call]

user_data

user data to pass to the save function.

[closure]

type

name of file format.

 

option_keys

name of options to set, NULL-terminated.

[array zero-terminated=1][element-type utf8]

option_values

values for named options.

[array zero-terminated=1][element-type utf8]

error

return location for error, or NULL.

[allow-none]

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 buffer will be set to NULL. Possible errors include those in the GDK_PIXBUF_ERROR domain.

See gdk_pixbuf_save() for more details.

Parameters

pixbuf

a GdkPixbuf.

 

buffer

location to receive a pointer to the new buffer.

[array length=buffer_size][out][element-type guint8]

buffer_size

location to receive the size of the new buffer.

 

type

name of file format.

 

error

return location for error, or NULL.

[allow-none]

...

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.

Parameters

pixbuf

a GdkPixbuf.

 

buffer

location to receive a pointer to the new buffer.

[array length=buffer_size][out][element-type guint8]

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.

[array zero-terminated=1]

option_values

values for named options.

[array zero-terminated=1]

error

return location for error, or NULL.

[allow-none]

Returns

whether an error was set

Since 2.4


gdk_pixbuf_save_to_stream ()

gboolean
gdk_pixbuf_save_to_stream (GdkPixbuf *pixbuf,
                           GOutputStream *stream,
                           const char *type,
                           GCancellable *cancellable,
                           GError **error,
                           ...);

Saves pixbuf to an output stream.

Supported file formats are currently "jpeg", "tiff", "png", "ico" or "bmp". See gdk_pixbuf_save_to_buffer() for more details.

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.

Parameters

pixbuf

a GdkPixbuf

 

stream

a GOutputStream to save the pixbuf to

 

type

name of file format

 

cancellable

optional GCancellable object, NULL to ignore.

[allow-none]

error

return location for error, or NULL.

[allow-none]

...

list of key-value save options

 

Returns

TRUE if the pixbuf was saved successfully, FALSE if an error was set.

Since 2.14


gdk_pixbuf_save_to_stream_async ()

void
gdk_pixbuf_save_to_stream_async (GdkPixbuf *pixbuf,
                                 GOutputStream *stream,
                                 const gchar *type,
                                 GCancellable *cancellable,
                                 GAsyncReadyCallback callback,
                                 gpointer user_data,
                                 ...);

Saves pixbuf to an output stream asynchronously.

For more details see gdk_pixbuf_save_to_stream(), which is the synchronous version of this function.

When the operation is finished, callback will be called in the main thread. You can then call gdk_pixbuf_save_to_stream_finish() to get the result of the operation.

Parameters

pixbuf

a GdkPixbuf

 

stream

a GOutputStream to which to save the pixbuf

 

type

name of file format

 

cancellable

optional GCancellable object, NULL to ignore.

[allow-none]

callback

a GAsyncReadyCallback to call when the the pixbuf is loaded

 

user_data

the data to pass to the callback function

 

...

list of key-value save options

 

Since 2.24


gdk_pixbuf_save_to_stream_finish ()

gboolean
gdk_pixbuf_save_to_stream_finish (GAsyncResult *async_result,
                                  GError **error);

Finishes an asynchronous pixbuf save operation started with gdk_pixbuf_save_to_stream_async().

Parameters

async_result

a GAsyncResult

 

error

a GError, or NULL

 

Returns

TRUE if the pixbuf was saved successfully, FALSE if an error was set.

Since 2.24

Types and Values