:right-sidebar: True PixbufLoader =================================================================== .. currentmodule:: gi.repository.GdkPixbuf .. class:: PixbufLoader(**properties: ~typing.Any) :no-contents-entry: Superclasses: :class:`~gi.repository.GObject.Object` Incremental image loader. ``GdkPixbufLoader`` provides a way for applications to drive the process of loading an image, by letting them send the image data directly to the loader instead of having the loader read the data from a file. Applications can use this functionality instead of ``gdk_pixbuf_new_from_file()`` or ``gdk_pixbuf_animation_new_from_file()`` when they need to parse image data in small chunks. For example, it should be used when reading an image from a (potentially) slow network connection, or when loading an extremely large file. To use ``GdkPixbufLoader`` to load an image, create a new instance, and call :obj:`~gi.repository.GdkPixbuf.PixbufLoader.write` to send the data to it. When done, :obj:`~gi.repository.GdkPixbuf.PixbufLoader.close` should be called to end the stream and finalize everything. The loader will emit three important signals throughout the process: - :obj:`~gi.repository.GdkPixbuf.PixbufLoader.signals.size_prepared` will be emitted as soon as the image has enough information to determine the size of the image to be used. If you want to scale the image while loading it, you can call :obj:`~gi.repository.GdkPixbuf.PixbufLoader.set_size` in response to this signal. - :obj:`~gi.repository.GdkPixbuf.PixbufLoader.signals.area_prepared` will be emitted as soon as the pixbuf of the desired has been allocated. You can obtain the ``GdkPixbuf`` instance by calling :obj:`~gi.repository.GdkPixbuf.PixbufLoader.get_pixbuf`\. If you want to use it, simply acquire a reference to it. You can also call ``gdk_pixbuf_loader_get_pixbuf()`` later to get the same pixbuf. - :obj:`~gi.repository.GdkPixbuf.PixbufLoader.signals.area_updated` will be emitted every time a region is updated. This way you can update a partially completed image. Note that you do not know anything about the completeness of an image from the updated area. For example, in an interlaced image you will need to make several passes before the image is done loading. Loading an animation -------------------------------------------------------------------------------- Loading an animation is almost as easy as loading an image. Once the first :obj:`~gi.repository.GdkPixbuf.PixbufLoader.signals.area_prepared` signal has been emitted, you can call :obj:`~gi.repository.GdkPixbuf.PixbufLoader.get_animation` to get the :obj:`~gi.repository.GdkPixbuf.PixbufAnimation` instance, and then call and :obj:`~gi.repository.GdkPixbuf.PixbufAnimation.get_iter` to get a :obj:`~gi.repository.GdkPixbuf.PixbufAnimationIter` to retrieve the pixbuf for the desired time stamp. Constructors ------------ .. rst-class:: interim-class .. class:: PixbufLoader :no-index: .. classmethod:: new() -> ~gi.repository.GdkPixbuf.PixbufLoader Creates a new pixbuf loader object. .. classmethod:: new_with_mime_type(mime_type: str) -> ~gi.repository.GdkPixbuf.PixbufLoader Creates a new pixbuf loader object that always attempts to parse image data as if it were an image of MIME type ``mime_type``\, instead of identifying the type automatically. This function is useful if you want an error if the image isn't the expected MIME type; for loading image formats that can't be reliably identified by looking at the data; or if the user manually forces a specific MIME type. The list of supported mime types depends on what image loaders are installed, but typically "image/png", "image/jpeg", "image/gif", "image/tiff" and "image/x-xpixmap" are among the supported mime types. To obtain the full list of supported mime types, call :func:`~gi.repository.GdkPixbuf.PixbufFormat.get_mime_types` on each of the :obj:`~gi.repository.GdkPixbuf.PixbufFormat` structs returned by :func:`~gi.repository.GdkPixbuf.Pixbuf.get_formats`. .. versionadded:: 2.4 :param mime_type: the mime type to be loaded .. classmethod:: new_with_type(image_type: str) -> ~gi.repository.GdkPixbuf.PixbufLoader Creates a new pixbuf loader object that always attempts to parse image data as if it were an image of type ``image_type``\, instead of identifying the type automatically. This function is useful if you want an error if the image isn't the expected type; for loading image formats that can't be reliably identified by looking at the data; or if the user manually forces a specific type. The list of supported image formats depends on what image loaders are installed, but typically "png", "jpeg", "gif", "tiff" and "xpm" are among the supported formats. To obtain the full list of supported image formats, call :func:`~gi.repository.GdkPixbuf.PixbufFormat.get_name` on each of the :obj:`~gi.repository.GdkPixbuf.PixbufFormat` structs returned by :func:`~gi.repository.GdkPixbuf.Pixbuf.get_formats`. :param image_type: name of the image format to be loaded with the image Methods ------- .. rst-class:: interim-class .. class:: PixbufLoader :no-index: .. method:: close() -> bool Informs a pixbuf loader that no further writes with :func:`~gi.repository.GdkPixbuf.PixbufLoader.write` will occur, so that it can free its internal loading structures. This function also tries to parse any data that hasn't yet been parsed; if the remaining data is partial or corrupt, an error will be returned. If ``FALSE`` is returned, ``error`` will be set to an error from the ``GDK_PIXBUF_ERROR`` or ``G_FILE_ERROR`` domains. If you're just cancelling a load rather than expecting it to be finished, passing ``NULL`` for ``error`` to ignore it is reasonable. Remember that this function does not release a reference on the loader, so you will need to explicitly release any reference you hold. .. method:: do_area_prepared(self) -> None .. method:: do_area_updated(self, x: int, y: int, width: int, height: int) -> None :param x: :param y: :param width: :param height: .. method:: do_closed(self) -> None .. method:: do_size_prepared(self, width: int, height: int) -> None :param width: :param height: .. method:: get_animation() -> ~gi.repository.GdkPixbuf.PixbufAnimation | None Queries the :obj:`~gi.repository.GdkPixbuf.PixbufAnimation` that a pixbuf loader is currently creating. In general it only makes sense to call this function after the :obj:`~gi.repository.GdkPixbuf.PixbufLoader.signals.area_prepared` signal has been emitted by the loader. If the loader doesn't have enough bytes yet, and hasn't emitted the ``area-prepared`` signal, this function will return ``NULL``\. .. method:: get_format() -> ~gi.repository.GdkPixbuf.PixbufFormat | None Obtains the available information about the format of the currently loading image file. .. versionadded:: 2.2 .. method:: get_pixbuf() -> ~gi.repository.GdkPixbuf.Pixbuf | None Queries the :obj:`~gi.repository.GdkPixbuf.Pixbuf` that a pixbuf loader is currently creating. In general it only makes sense to call this function after the :obj:`~gi.repository.GdkPixbuf.PixbufLoader.signals.area_prepared` signal has been emitted by the loader; this means that enough data has been read to know the size of the image that will be allocated. If the loader has not received enough data via :func:`~gi.repository.GdkPixbuf.PixbufLoader.write`, then this function returns ``NULL``\. The returned pixbuf will be the same in all future calls to the loader, so if you want to keep using it, you should acquire a reference to it. Additionally, if the loader is an animation, it will return the "static image" of the animation (see :func:`~gi.repository.GdkPixbuf.PixbufAnimation.get_static_image`). .. method:: set_size(width: int, height: int) -> None Causes the image to be scaled while it is loaded. The desired image size can be determined relative to the original size of the image by calling :func:`~gi.repository.GdkPixbuf.PixbufLoader.set_size` from a signal handler for the ::size-prepared signal. Attempts to set the desired image size are ignored after the emission of the ::size-prepared signal. .. versionadded:: 2.2 :param width: The desired width of the image being loaded. :param height: The desired height of the image being loaded. .. method:: write(buf: list[int]) -> bool Parses the next ``count`` bytes in the given image buffer. :param buf: Pointer to image data. .. method:: write_bytes(buffer: ~gi.repository.GLib.Bytes) -> bool Parses the next contents of the given image buffer. .. versionadded:: 2.30 :param buffer: The image data as a ``GBytes`` buffer. Signals ------- .. rst-class:: interim-class .. class:: PixbufLoader.signals :no-index: .. method:: area_prepared() -> None The type of the None singleton. .. method:: area_updated(x: int, y: int, width: int, height: int) -> None The type of the None singleton. :param x: X offset of upper-left corner of the updated area. :param y: Y offset of upper-left corner of the updated area. :param width: Width of updated area. :param height: Height of updated area. .. method:: closed() -> None The type of the None singleton. .. method:: size_prepared(width: int, height: int) -> None The type of the None singleton. :param width: the original width of the image :param height: the original height of the image Virtual Methods --------------- .. rst-class:: interim-class .. class:: PixbufLoader :no-index: .. method:: do_area_prepared() -> None The type of the None singleton. .. method:: do_area_updated(x: int, y: int, width: int, height: int) -> None The type of the None singleton. :param x: :param y: :param width: :param height: .. method:: do_closed() -> None The type of the None singleton. .. method:: do_size_prepared(width: int, height: int) -> None The type of the None singleton. :param width: :param height: Fields ------ .. rst-class:: interim-class .. class:: PixbufLoader :no-index: .. attribute:: parent_instance .. attribute:: priv