Class Pixbuf

java.lang.Object
org.javagi.base.ProxyInstance
org.gnome.gobject.TypeInstance
org.gnome.gobject.GObject
org.gnome.gdkpixbuf.Pixbuf
All Implemented Interfaces:
Icon, LoadableIcon, Proxy
@Generated("org.javagi.JavaGI") public class Pixbuf extends GObject implements Icon, LoadableIcon

A pixel buffer.

GdkPixbuf contains information about an image's pixel data, its color space, bits per sample, width and height, and the rowstride (the number of bytes between the start of one row and the start of the next).

Creating new GdkPixbuf

The most basic way to create a pixbuf is to wrap an existing pixel buffer with a Pixbuf instance. You can use the `GdkPixbuf.Pixbuf.new_from_data`` function to do this.

Every time you create a new GdkPixbuf instance for some data, you will 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 GdkPixbuf.Pixbuf.new`` constructor 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 withgdk_pixbuf_new_from_data(). The gdk_pixbuf_new()` function will compute an optimal rowstride so that rendering can be performed with an efficient algorithm.

You can also copy an existing pixbuf with the copy() function. This is not the same as just acquiring a reference to the old pixbuf instance: the copy function will actually duplicate the pixel data in memory and create a new Pixbuf instance for it.

Reference counting

GdkPixbuf structures are reference counted. This means that an application can share a single pixbuf among many parts of the code. When a piece of the program needs to use a pixbuf, it should acquire a reference to it by calling g_object_ref(); when it no longer needs the pixbuf, it should release the reference it acquired by calling g_object_unref(). The resources associated with a GdkPixbuf will be freed when its reference count drops to zero. Newly-created GdkPixbuf instances start with a reference count of one.

Image Data

Image data in a pixbuf is stored in memory in an uncompressed, packed format. Rows in the image are stored top to bottom, and in each row pixels are stored from left to right.

There may be padding at the end of a row.

The "rowstride" value of a pixbuf, as returned by `GdkPixbuf.Pixbuf.get_rowstride``, indicates the number of bytes between rows.

NOTE: If you are copying raw pixbuf data with memcpy() note that the last row in the pixbuf may not be as wide as the full rowstride, but rather just as wide as the pixel data needs to be; that is: it is unsafe to do memcpy (dest, pixels, rowstride * height) to copy a whole pixbuf. Use copy() instead, or compute the width in bytes of the last row as:

last_row = width * ((n_channels * bits_per_sample + 7) / 8);

The same rule applies when iterating over each row of a GdkPixbuf pixels array.

The following code illustrates a simple put_pixel() function for RGB pixbufs with 8 bits per channel with an alpha channel.

static void
put_pixel (GdkPixbuf *pixbuf,
           int x,
	   int y,
	   guchar red,
	   guchar green,
	   guchar blue,
	   guchar alpha)
{
  int n_channels = gdk_pixbuf_get_n_channels (pixbuf);

  // Ensure that the pixbuf is valid
  g_assert (gdk_pixbuf_get_colorspace (pixbuf) == GDK_COLORSPACE_RGB);
  g_assert (gdk_pixbuf_get_bits_per_sample (pixbuf) == 8);
  g_assert (gdk_pixbuf_get_has_alpha (pixbuf));
  g_assert (n_channels == 4);

  int width = gdk_pixbuf_get_width (pixbuf);
  int height = gdk_pixbuf_get_height (pixbuf);

  // Ensure that the coordinates are in a valid range
  g_assert (x >= 0 && x < width);
  g_assert (y >= 0 && y < height);

  int rowstride = gdk_pixbuf_get_rowstride (pixbuf);

  // The pixel buffer in the GdkPixbuf instance
  guchar *pixels = gdk_pixbuf_get_pixels (pixbuf);

  // The pixel we wish to modify
  guchar *p = pixels + y * rowstride + x * n_channels;
  p[0] = red;
  p[1] = green;
  p[2] = blue;
  p[3] = alpha;
}

Loading images

The GdkPixBuf class provides a simple mechanism for loading an image from a file in synchronous and asynchronous fashion.

For GUI applications, it is recommended to use the asynchronous stream API to avoid blocking the control flow of the application.

Additionally, GdkPixbuf provides the `PixbufLoader`` API for progressive image loading.

Saving images

The GdkPixbuf class provides methods for saving image data 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.

  • Constructor Details

    • Pixbuf

      public Pixbuf(MemorySegment address)
      Create a Pixbuf instance for the provided memory address.
      Parameters:
      address - the memory address of the native object

    • Pixbuf

      public Pixbuf(Colorspace colorspace, boolean hasAlpha, int bitsPerSample, int width, int height)

      Creates a new GdkPixbuf structure and allocates a buffer for it.

      If the allocation of the buffer failed, this function will return NULL.

      The buffer has an optimal rowstride. Note that the buffer is not cleared; you will have to fill it completely yourself.

      Parameters:
      colorspace - Color space for image
      hasAlpha - Whether the image should have transparency information
      bitsPerSample - Number of bits per color sample
      width - Width of image in pixels, must be > 0
      height - Height of image in pixels, must be > 0

    • Pixbuf

      public Pixbuf()
      Create a new Pixbuf.

  • Method Details

    • getType

      public static @Nullable Type getType()
      Get the GType of the Pixbuf class.
      Returns:
      the GType

    • getMemoryLayout

      public static MemoryLayout getMemoryLayout()
      The memory layout of the native struct.
      Returns:
      the memory layout

    • asParent

      protected Pixbuf asParent()
      Return this instance as if it were its parent type. Comparable to the Java super keyword, but ensures the parent typeclass is also used in native code.
      Overrides:
      asParent in class GObject
      Returns:
      the instance as if it were its parent type

    • fromBytes

      public static Pixbuf fromBytes(byte[] data, Colorspace colorspace, boolean hasAlpha, int bitsPerSample, int width, int height, int rowstride)

      Creates a new GdkPixbuf out of in-memory readonly image data.

      Currently only RGB images with 8 bits per sample are supported.

      This is the GBytes variant of gdk_pixbuf_new_from_data(), useful for language bindings.

      Parameters:
      data - Image data in 8-bit/sample packed format inside a GBytes
      colorspace - Colorspace for the image data
      hasAlpha - Whether the data has an opacity channel
      bitsPerSample - 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
      Returns:
      A newly-created pixbuf
      Since:
      2.32

    • fromData

      public static Pixbuf fromData(@Nullable byte @Nullable [] data, Colorspace colorspace, boolean hasAlpha, int bitsPerSample, int width, int height, int rowstride, @Nullable PixbufDestroyNotify destroyFn)

      Creates a new GdkPixbuf out of in-memory image data.

      Currently only RGB images with 8 bits per sample are supported.

      Since you are providing a pre-allocated pixel buffer, you must also specify a way to free that data. This is done with a function of type GdkPixbufDestroyNotify. When a pixbuf created with is finalized, your destroy notification function will be called, and it is its responsibility to free the pixel array.

      See also: fromBytes(byte[], Colorspace, boolean, int, int, int, int)

      Parameters:
      data - Image data in 8-bit/sample packed format
      colorspace - Colorspace for the image data
      hasAlpha - Whether the data has an opacity channel
      bitsPerSample - 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
      destroyFn - Function used to free the data when the pixbuf's reference count drops to zero, or NULL if the data should not be freed
      Returns:
      A newly-created pixbuf

    • fromFile

      public static @Nullable Pixbuf fromFile(String filename) throws GErrorException

      Creates a new pixbuf by loading an image from a file.

      The file format is detected automatically.

      If NULL is returned, then error will be set. Possible errors are:

      • the file could not be opened
      • there is no loader for the file's format
      • there is not enough memory to allocate the image buffer
      • the image buffer contains invalid data

      The error domains are GDK_PIXBUF_ERROR and G_FILE_ERROR.

      Parameters:
      filename - Name of file to load, in the GLib file name encoding
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError

    • fromFileAtScale

      public static @Nullable Pixbuf fromFileAtScale(String filename, int width, int height, boolean preserveAspectRatio) throws GErrorException

      Creates a new pixbuf by loading an image from a file.

      The file format is detected automatically.

      If NULL is returned, then error will be set. Possible errors are:

      • the file could not be opened
      • there is no loader for the file's format
      • there is not enough memory to allocate the image buffer
      • the image buffer contains invalid data

      The error domains are GDK_PIXBUF_ERROR and G_FILE_ERROR.

      The image will be scaled to fit in the requested size, optionally preserving the image's aspect ratio.

      When preserving the aspect ratio, a width of -1 will cause the image to be scaled to the exact given height, and a height of -1 will cause the image to be scaled to the exact given width. When not preserving aspect ratio, a width or height of -1 means to not scale the image at all in that dimension. Negative values for width and height are allowed since 2.8.

      Parameters:
      filename - Name of file to load, in the GLib file name encoding
      width - The width the image should have or -1 to not constrain the width
      height - The height the image should have or -1 to not constrain the height
      preserveAspectRatio - TRUE to preserve the image's aspect ratio
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError
      Since:
      2.6

    • fromFileAtSize

      public static @Nullable Pixbuf fromFileAtSize(String filename, int width, int height) throws GErrorException

      Creates a new pixbuf by loading an image from a file.

      The file format is detected automatically.

      If NULL is returned, then error will be set. Possible errors are:

      • the file could not be opened
      • there is no loader for the file's format
      • there is not enough memory to allocate the image buffer
      • the image buffer contains invalid data

      The error domains are GDK_PIXBUF_ERROR and G_FILE_ERROR.

      The image will be scaled to fit in the requested size, preserving the image's aspect ratio. Note that the returned pixbuf may be smaller than width x height, if the aspect ratio requires it. To load and image at the requested size, regardless of aspect ratio, use fromFileAtScale(String, int, int, boolean).

      Parameters:
      filename - Name of file to load, in the GLib file name encoding
      width - The width the image should have or -1 to not constrain the width
      height - The height the image should have or -1 to not constrain the height
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError
      Since:
      2.4

    • fromInline

      @Deprecated public static Pixbuf fromInline(@Nullable byte @Nullable [] data, boolean copyPixels) throws GErrorException
      Deprecated.
      Use GResource instead.

      Creates 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.

      GdkPixbuf 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 option to gdk-pixbuf-csource. A sample invocation would be:

      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:

      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.

      Parameters:
      data - Byte data containing a serialized GdkPixdata structure
      copyPixels - Whether to copy the pixel data, or use direct pointers data for the resulting pixbuf
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError

    • fromResource

      public static @Nullable Pixbuf fromResource(String resourcePath) throws GErrorException

      Creates a new pixbuf by loading an image from an resource.

      The file format is detected automatically. If NULL is returned, then error will be set.

      Parameters:
      resourcePath - the path of the resource file
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError
      Since:
      2.26

    • fromResourceAtScale

      public static @Nullable Pixbuf fromResourceAtScale(String resourcePath, int width, int height, boolean preserveAspectRatio) throws GErrorException

      Creates a new pixbuf by loading an image from an resource.

      The file format is detected automatically. If NULL is returned, then error will be set.

      The image will be scaled to fit in the requested size, optionally preserving the image's aspect ratio. When preserving the aspect ratio, a width of -1 will cause the image to be scaled to the exact given height, and a height of -1 will cause the image to be scaled to the exact given width. When not preserving aspect ratio, a width or height of -1 means to not scale the image at all in that dimension.

      The stream is not closed.

      Parameters:
      resourcePath - the path of the resource file
      width - The width the image should have or -1 to not constrain the width
      height - The height the image should have or -1 to not constrain the height
      preserveAspectRatio - TRUE to preserve the image's aspect ratio
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError
      Since:
      2.26

    • fromStream

      public static @Nullable Pixbuf fromStream(InputStream stream, @Nullable Cancellable cancellable) throws GErrorException

      Creates a new pixbuf by loading an image from an input stream.

      The file format is detected automatically.

      If NULL is returned, then error will be set.

      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:
      stream - a GInputStream to load the pixbuf from
      cancellable - optional GCancellable object, NULL to ignore
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError
      Since:
      2.14

    • fromStreamAtScale

      public static @Nullable Pixbuf fromStreamAtScale(InputStream stream, int width, int height, boolean preserveAspectRatio, @Nullable Cancellable cancellable) throws GErrorException

      Creates a new pixbuf by loading an image from an input stream.

      The file format is detected automatically. If NULL is returned, then error will be set. 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 image will be scaled to fit in the requested size, optionally preserving the image's aspect ratio.

      When preserving the aspect ratio, a width of -1 will cause the image to be scaled to the exact given height, and a height of -1 will cause the image to be scaled to the exact given width. If both width and height are given, this function will behave as if the smaller of the two values is passed as -1.

      When not preserving aspect ratio, a width or height of -1 means to not scale the image at all in that dimension.

      The stream is not closed.

      Parameters:
      stream - a GInputStream to load the pixbuf from
      width - The width the image should have or -1 to not constrain the width
      height - The height the image should have or -1 to not constrain the height
      preserveAspectRatio - TRUE to preserve the image's aspect ratio
      cancellable - optional GCancellable object, NULL to ignore
      Returns:
      A newly-created pixbuf
      Throws:
      GErrorException - see GError
      Since:
      2.14

    • fromStreamFinish

      public static @Nullable Pixbuf fromStreamFinish(AsyncResult asyncResult) throws GErrorException
      Finishes an asynchronous pixbuf creation operation started with gdk_pixbuf_new_from_stream_async().
      Parameters:
      asyncResult - a GAsyncResult
      Returns:
      the newly created pixbuf
      Throws:
      GErrorException - see GError
      Since:
      2.24

    • fromXpmData

      @Deprecated public static @Nullable Pixbuf fromXpmData(@Nullable String @Nullable [] data)
      Deprecated.
      Use fromStream(InputStream, Cancellable) with a MemoryInputStream, making sure to handle errors in case the XPM format loader is not available

      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.

      Parameters:
      data - Pointer to inline XPM data.
      Returns:
      A newly-created pixbuf

    • fromFileAtScaleUtf8

      public static @Nullable Pixbuf fromFileAtScaleUtf8(String filename, int width, int height, boolean preserveAspectRatio) throws GErrorException
      Same as gdk_pixbuf_new_from_file_at_scale().
      Parameters:
      filename - Name of file to load, in the GLib file name encoding
      width - The width the image should have or -1 to not constrain the width
      height - The height the image should have or -1 to not constrain the height
      preserveAspectRatio - TRUE to preserve the image's aspect ratio
      Returns:
      A newly-created pixbuf with a reference count of 1, or NULL if any of several error conditions occurred: the file could not be opened, there was no loader for the file's format, there was not enough memory to allocate the image buffer, or the image file contained invalid data.
      Throws:
      GErrorException - see GError
      Since:
      2.6

    • fromFileAtSizeUtf8

      public static @Nullable Pixbuf fromFileAtSizeUtf8(String filename, int width, int height) throws GErrorException
      Same as gdk_pixbuf_new_from_file_at_size()
      Parameters:
      filename - Name of file to load, in the GLib file name encoding
      width - The width the image should have or -1 to not constrain the width
      height - The height the image should have or -1 to not constrain the height
      Returns:
      A newly-created pixbuf with a reference count of 1, or NULL if any of several error conditions occurred: the file could not be opened, there was no loader for the file's format, there was not enough memory to allocate the image buffer, or the image file contained invalid data.
      Throws:
      GErrorException - see GError
      Since:
      2.4

    • fromFileUtf8

      public static @Nullable Pixbuf fromFileUtf8(String filename) throws GErrorException
      Same as gdk_pixbuf_new_from_file()
      Parameters:
      filename - Name of file to load, in the GLib file name encoding
      Returns:
      A newly-created pixbuf with a reference count of 1, or NULL if any of several error conditions occurred: the file could not be opened, there was no loader for the file's format, there was not enough memory to allocate the image buffer, or the image file contained invalid data.
      Throws:
      GErrorException - see GError

    • calculateRowstride

      public static int calculateRowstride(Colorspace colorspace, boolean hasAlpha, int bitsPerSample, int width, int height)

      Calculates the rowstride that an image created with those values would have.

      This function is useful for front-ends and backends that want to check image values without needing to create a GdkPixbuf.

      Parameters:
      colorspace - Color space for image
      hasAlpha - Whether the image should have transparency information
      bitsPerSample - 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:
      the rowstride for the given values, or -1 in case of error.
      Since:
      2.36.8

    • getFileInfo

      public static @Nullable PixbufFormat getFileInfo(String filename, @Nullable Out<Integer> width, @Nullable Out<Integer> height)
      Parses an image file far enough to determine its format and size.
      Parameters:
      filename - The name of the file to identify.
      width - Return location for the width of the image
      height - Return location for the height of the image
      Returns:
      A GdkPixbufFormat describing the image format of the file
      Since:
      2.4

    • getFileInfoAsync

      public static void getFileInfoAsync(String filename, @Nullable Cancellable cancellable, @Nullable AsyncReadyCallback callback)

      Asynchronously parses an image file far enough to determine its format and size.

      For more details see gdk_pixbuf_get_file_info(), 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_get_file_info_finish() to get the result of the operation.

      Parameters:
      filename - The name of the file to identify
      cancellable - optional GCancellable object, NULL to ignore
      callback - a GAsyncReadyCallback to call when the file info is available
      Since:
      2.32

    • getFileInfoFinish

      public static @Nullable PixbufFormat getFileInfoFinish(AsyncResult asyncResult, Out<Integer> width, Out<Integer> height) throws GErrorException
      Finishes an asynchronous pixbuf parsing operation started with gdk_pixbuf_get_file_info_async().
      Parameters:
      asyncResult - a GAsyncResult
      width - Return location for the width of the image, or NULL
      height - Return location for the height of the image, or NULL
      Returns:
      A GdkPixbufFormat describing the image format of the file
      Throws:
      GErrorException - see GError
      Since:
      2.32

    • getFormats

      public static SList<PixbufFormat> getFormats()
      Obtains the available information about the image formats supported by GdkPixbuf.
      Returns:
      A list of support image formats.
      Since:
      2.2

    • initModules

      public static boolean initModules(String path) throws GErrorException

      Initalizes the gdk-pixbuf loader modules referenced by the loaders.cache file present inside that directory.

      This is to be used by applications that want to ship certain loaders in a different location from the system ones.

      This is needed when the OS or runtime ships a minimal number of loaders so as to reduce the potential attack surface of carefully crafted image files, especially for uncommon file types. Applications that require broader image file types coverage, such as image viewers, would be expected to ship the gdk-pixbuf modules in a separate location, bundled with the application in a separate directory from the OS or runtime- provided modules.

      Parameters:
      path - Path to directory where the loaders.cache is installed
      Throws:
      GErrorException - see GError
      Since:
      2.40

    • newFromStreamAsync

      public static void newFromStreamAsync(InputStream stream, @Nullable Cancellable cancellable, @Nullable AsyncReadyCallback callback)

      Creates a new pixbuf by asynchronously loading an image from an input stream.

      For more details see gdk_pixbuf_new_from_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_new_from_stream_finish() to get the result of the operation.

      Parameters:
      stream - a GInputStream from which to load the pixbuf
      cancellable - optional GCancellable object, NULL to ignore
      callback - a GAsyncReadyCallback to call when the pixbuf is loaded
      Since:
      2.24

    • newFromStreamAtScaleAsync

      public static void newFromStreamAtScaleAsync(InputStream stream, int width, int height, boolean preserveAspectRatio, @Nullable Cancellable cancellable, @Nullable AsyncReadyCallback callback)

      Creates a new pixbuf by asynchronously loading an image from an input stream.

      For more details see gdk_pixbuf_new_from_stream_at_scale(), 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_new_from_stream_finish() to get the result of the operation.

      Parameters:
      stream - a GInputStream from which to load the pixbuf
      width - the width the image should have or -1 to not constrain the width
      height - the height the image should have or -1 to not constrain the height
      preserveAspectRatio - TRUE to preserve the image's aspect ratio
      cancellable - optional GCancellable object, NULL to ignore
      callback - a GAsyncReadyCallback to call when the pixbuf is loaded
      Since:
      2.24

    • saveToStreamFinish

      public static boolean saveToStreamFinish(AsyncResult asyncResult) throws GErrorException
      Finishes an asynchronous pixbuf save operation started with gdk_pixbuf_save_to_stream_async().
      Parameters:
      asyncResult - a GAsyncResult
      Returns:
      TRUE if the pixbuf was saved successfully, FALSE if an error was set.
      Throws:
      GErrorException - see GError
      Since:
      2.24

    • addAlpha

      public @Nullable Pixbuf addAlpha(boolean substituteColor, byte r, byte g, byte b)

      Takes an existing pixbuf and adds an alpha channel to it.

      If the existing pixbuf already had an alpha channel, the channel values are copied from the original; otherwise, the alpha channel is initialized to 255 (full opacity).

      If substitute_color is TRUE, then the color specified by the (r, g, b) arguments will be assigned zero opacity. That is, if you pass (255, 255, 255) for the substitute color, all white pixels will become fully transparent.

      If substitute_color is FALSE, then the (r, g, b) arguments will be ignored.

      Parameters:
      substituteColor - Whether to set a color to zero opacity.
      r - Red value to substitute.
      g - Green value to substitute.
      b - Blue value to substitute.
      Returns:
      A newly-created pixbuf

    • applyEmbeddedOrientation

      public @Nullable Pixbuf applyEmbeddedOrientation()

      Takes an existing pixbuf and checks for the presence of an associated "orientation" option.

      The orientation option may be provided by the JPEG loader (which reads the exif orientation tag) or the TIFF loader (which reads the TIFF orientation tag, and compensates it for the partial transforms performed by libtiff).

      If an orientation option/tag is present, the appropriate transform will be performed so that the pixbuf is oriented correctly.

      Returns:
      A newly-created pixbuf
      Since:
      2.12

    • composite

      public void composite(Pixbuf dest, int destX, int destY, int destWidth, int destHeight, double offsetX, double offsetY, double scaleX, double scaleY, InterpType interpType, int overallAlpha)

      Creates a transformation of the source image this Pixbuf by scaling by scaleX and scaleY then translating by offsetX and offsetY.

      This gives an image in the coordinates of the destination pixbuf. The rectangle (destX, destY, destWidth, destHeight) is then alpha blended onto the corresponding rectangle of the original destination image.

      When the destination rectangle contains parts not in the source image, the data at the edges of the source image is replicated to infinity.

      Parameters:
      dest - the GdkPixbuf into which to render the results
      destX - the left coordinate for region to render
      destY - the top coordinate for region to render
      destWidth - the width of the region to render
      destHeight - the height of the region to render
      offsetX - the offset in the X direction (currently rounded to an integer)
      offsetY - the offset in the Y direction (currently rounded to an integer)
      scaleX - the scale factor in the X direction
      scaleY - the scale factor in the Y direction
      interpType - the interpolation type for the transformation.
      overallAlpha - overall alpha for source image (0..255)

    • compositeColor

      public void compositeColor(Pixbuf dest, int destX, int destY, int destWidth, int destHeight, double offsetX, double offsetY, double scaleX, double scaleY, InterpType interpType, int overallAlpha, int checkX, int checkY, int checkSize, int color1, int color2)

      Creates a transformation of the source image this Pixbuf by scaling by scaleX and scaleY then translating by offsetX and offsetY, then alpha blends the rectangle (destX ,destY, destWidth, destHeight) of the resulting image with a checkboard of the colors color1 and color2 and renders it onto the destination image.

      If the source image has no alpha channel, and overallAlpha is 255, a fast path is used which omits the alpha blending and just performs the scaling.

      See gdk_pixbuf_composite_color_simple() for a simpler variant of this function suitable for many tasks.

      Parameters:
      dest - the GdkPixbuf into which to render the results
      destX - the left coordinate for region to render
      destY - the top coordinate for region to render
      destWidth - the width of the region to render
      destHeight - the height of the region to render
      offsetX - the offset in the X direction (currently rounded to an integer)
      offsetY - the offset in the Y direction (currently rounded to an integer)
      scaleX - the scale factor in the X direction
      scaleY - the scale factor in the Y direction
      interpType - the interpolation type for the transformation.
      overallAlpha - overall alpha for source image (0..255)
      checkX - the X offset for the checkboard (origin of checkboard is at -checkX, -checkY)
      checkY - the Y offset for the checkboard
      checkSize - the size of checks in the checkboard (must be a power of two)
      color1 - the color of check at upper left
      color2 - the color of the other check

    • compositeColorSimple

      public @Nullable Pixbuf compositeColorSimple(int destWidth, int destHeight, InterpType interpType, int overallAlpha, int checkSize, int color1, int color2)
      Creates a new pixbuf by scaling src to dest_width x dest_height and alpha blending the result with a checkboard of colors color1 and color2.
      Parameters:
      destWidth - the width of destination image
      destHeight - the height of destination image
      interpType - the interpolation type for the transformation.
      overallAlpha - overall alpha for source image (0..255)
      checkSize - the size of checks in the checkboard (must be a power of two)
      color1 - the color of check at upper left
      color2 - the color of the other check
      Returns:
      the new pixbuf

    • copy

      public @Nullable Pixbuf copy()

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

      Note that this does not copy the options set on the original GdkPixbuf, use gdk_pixbuf_copy_options() for this.

      Returns:
      A newly-created pixbuf

    • copyArea

      public void copyArea(int srcX, int srcY, int width, int height, Pixbuf destPixbuf, int destX, int destY)

      Copies a rectangular area from src_pixbuf to dest_pixbuf.

      Conversion of pixbuf formats is done automatically.

      If the source rectangle overlaps the destination rectangle on the same pixbuf, it will be overwritten during the copy operation. Therefore, you can not use this function to scroll a pixbuf.

      Parameters:
      srcX - Source X coordinate within srcPixbuf.
      srcY - Source Y coordinate within srcPixbuf.
      width - Width of the area to copy.
      height - Height of the area to copy.
      destPixbuf - Destination pixbuf.
      destX - X coordinate within destPixbuf.
      destY - Y coordinate within destPixbuf.

    • copyOptions

      public boolean copyOptions(Pixbuf destPixbuf)

      Copies the key/value pair options attached to a GdkPixbuf to another GdkPixbuf.

      This is useful to keep original metadata after having manipulated a file. However be careful to remove metadata which you've already applied, such as the "orientation" option after rotating the image.

      Parameters:
      destPixbuf - the destination pixbuf
      Returns:
      TRUE on success.
      Since:
      2.36

    • fill

      public void fill(int pixel)

      Clears a pixbuf to the given RGBA value, converting the RGBA value into the pixbuf's pixel format.

      The alpha component will be ignored if the pixbuf doesn't have an alpha channel.

      Parameters:
      pixel - RGBA pixel to used to clear (0xffffffff is opaque white, 0x00000000 transparent black)

    • flip

      public @Nullable Pixbuf flip(boolean horizontal)
      Flips a pixbuf horizontally or vertically and returns the result in a new pixbuf.
      Parameters:
      horizontal - TRUE to flip horizontally, FALSE to flip vertically
      Returns:
      the new pixbuf
      Since:
      2.6

    • getBitsPerSample

      public int getBitsPerSample()
      Queries the number of bits per color sample in a pixbuf.
      Returns:
      Number of bits per color sample.

    • getByteLength

      public long getByteLength()
      Returns the length of the pixel data, in bytes.
      Returns:
      The length of the pixel data.
      Since:
      2.26

    • getColorspace

      public Colorspace getColorspace()
      Queries the color space of a pixbuf.
      Returns:
      Color space.

    • getHasAlpha

      public boolean getHasAlpha()
      Queries whether a pixbuf has an alpha channel (opacity information).
      Returns:
      TRUE if it has an alpha channel, FALSE otherwise.

    • getHeight

      public int getHeight()
      Queries the height of a pixbuf.
      Returns:
      Height in pixels.

    • getNChannels

      public int getNChannels()
      Queries the number of channels of a pixbuf.
      Returns:
      Number of channels.

    • getOption

      public @Nullable String getOption(String key)

      Looks up key in the list of options that may have been attached to the this Pixbuf when it was loaded, or that may have been attached by another function using gdk_pixbuf_set_option().

      For instance, the ANI loader provides "Title" and "Artist" options. The ICO, XBM, and XPM loaders provide "x_hot" and "y_hot" hot-spot options for cursor definitions. The PNG loader provides the tEXt ancillary chunk key/value pairs as options. Since 2.12, the TIFF and JPEG loaders return an "orientation" option string that corresponds to the embedded TIFF/Exif orientation tag (if present). Since 2.32, the TIFF loader sets the "multipage" option string to "yes" when a multi-page TIFF is loaded. Since 2.32 the JPEG and PNG loaders set "x-dpi" and "y-dpi" if the file contains image density information in dots per inch. Since 2.36.6, the JPEG loader sets the "comment" option with the comment EXIF tag.

      Parameters:
      key - a nul-terminated string.
      Returns:
      the value associated with key

    • getOptions

      public HashTable<String,String> getOptions()
      Returns a GHashTable with a list of all the options that may have been attached to the pixbuf when it was loaded, or that may have been attached by another function using setOption(String, String).
      Returns:
      a GHashTable of key/values pairs
      Since:
      2.32

    • getPixels

      public byte[] getPixels()

      Queries a pointer to the pixel data of a pixbuf.

      This function will cause an implicit copy of the pixbuf data if the pixbuf was created from read-only data.

      Please see the section on image data for information about how the pixel data is stored in memory.

      Returns:
      A pointer to the pixbuf's pixel data.
      Since:
      2.26

    • getRowstride

      public int getRowstride()
      Queries the rowstride of a pixbuf, which is the number of bytes between the start of a row and the start of the next row.
      Returns:
      Distance between row starts.

    • getWidth

      public int getWidth()
      Queries the width of a pixbuf.
      Returns:
      Width in pixels.

    • newSubpixbuf

      public Pixbuf newSubpixbuf(int srcX, int srcY, 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.

      Note that if src_pixbuf is read-only, this function will force it to be mutable.

      Parameters:
      srcX - X coord in this Pixbuf
      srcY - Y coord in this Pixbuf
      width - width of region in this Pixbuf
      height - height of region in this Pixbuf
      Returns:
      a new pixbuf

    • readPixelBytes

      public byte[] readPixelBytes()

      Provides a GBytes buffer containing the raw pixel data; the data must not be modified.

      This function allows skipping the implicit copy that must be made if gdk_pixbuf_get_pixels() is called on a read-only pixbuf.

      Returns:
      A new reference to a read-only copy of the pixel data. Note that for mutable pixbufs, this function will incur a one-time copy of the pixel data for conversion into the returned GBytes.
      Since:
      2.32

    • readPixels

      public MemorySegment readPixels()

      Provides a read-only pointer to the raw pixel data.

      This function allows skipping the implicit copy that must be made if gdk_pixbuf_get_pixels() is called on a read-only pixbuf.

      Returns:
      a read-only pointer to the raw pixel data
      Since:
      2.32

    • ref

      @Deprecated public Pixbuf ref()
      Deprecated.
      Use g_object_ref().
      Adds a reference to a pixbuf.
      Overrides:
      ref in class GObject
      Returns:
      The same as the this Pixbuf argument.

    • removeOption

      public boolean removeOption(String key)
      Removes the key/value pair option attached to a GdkPixbuf.
      Parameters:
      key - a nul-terminated string representing the key to remove.
      Returns:
      TRUE if an option was removed, FALSE if not.
      Since:
      2.36

    • rotateSimple

      public @Nullable Pixbuf rotateSimple(PixbufRotation angle)

      Rotates a pixbuf by a multiple of 90 degrees, and returns the result in a new pixbuf.

      If angle is 0, this function will return a copy of src.

      Parameters:
      angle - the angle to rotate by
      Returns:
      the new pixbuf
      Since:
      2.6

    • saturateAndPixelate

      public void saturateAndPixelate(Pixbuf dest, float saturation, boolean pixelate)

      Modifies saturation and optionally pixelates src, placing the result in dest.

      The src and dest pixbufs must have the same image format, size, and rowstride.

      The src and dest arguments may be the same pixbuf with no ill effects.

      If saturation is 1.0 then saturation is not changed. If it's less than 1.0, saturation is reduced (the image turns toward grayscale); if greater than 1.0, saturation is increased (the image gets more vivid colors).

      If pixelate is TRUE, then pixels are faded in a checkerboard pattern to create a pixelated image.

      Parameters:
      dest - place to write modified version of this Pixbuf
      saturation - saturation factor
      pixelate - whether to pixelate

    • save

      public boolean save(String filename, String type, GError[] error, Object... varargs)

      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]. JPEG and PNG density can be set by setting the "x-dpi" and "y-dpi" parameters to the appropriate values in dots per inch.

      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.

      char *contents;
gsize length;

// icm_path is set elsewhere
g_file_get_contents (icm_path, &contents, &length, NULL);

char *contents_encode = g_base64_encode ((const guchar *) contents, length);

gdk_pixbuf_save (pixbuf, handle, "png", &error, "icc-profile", contents_encode, NULL);

      TIFF images recognize:

      1. a "bits-per-sample" option (integer) which can be either 1 for saving bi-level CCITTFAX4 images, or 8 for saving 8-bits per sample
      2. a "compression" option (integer) which can be 1 for no compression, 2 for Huffman, 5 for LZW, 7 for JPEG and 8 for DEFLATE (see the libtiff documentation and tiff.h for all supported codec values)
      3. an "icc-profile" option (zero-terminated string) containing a base64 encoded ICC color profile.

      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:
      filename - name of file to save.
      type - name of file format.
      error - return location for error
      varargs - list of key-value save options, followed by NULL
      Returns:
      TRUE on success, and FALSE otherwise

    • saveToBuffer

      public boolean saveToBuffer(@Nullable Out<byte[]> buffer, String type, GError[] error, Object... varargs)

      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 NUL characters.

      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:
      buffer - location to receive a pointer to the new buffer.
      type - name of file format.
      error - return location for error, or NULL
      varargs - list of key-value save options
      Returns:
      whether an error was set
      Since:
      2.4

    • saveToBufferv

      public boolean saveToBufferv(@Nullable Out<byte[]> buffer, String type, @Nullable String @Nullable [] optionKeys, @Nullable String @Nullable [] optionValues) throws GErrorException

      Vector version of gdk_pixbuf_save_to_buffer().

      Saves pixbuf to a new buffer in format type, which is currently "jpeg", "tiff", "png", "ico" or "bmp".

      See saveToBuffer(Out, String, GError[], Object...) for more details.

      Parameters:
      buffer - location to receive a pointer to the new buffer.
      type - name of file format.
      optionKeys - name of options to set
      optionValues - values for named options
      Returns:
      whether an error was set
      Throws:
      GErrorException - see GError
      Since:
      2.4

    • saveToCallback

      public boolean saveToCallback(@Nullable PixbufSaveFunc saveFunc, String type, GError[] error, Object... varargs)

      Saves pixbuf in format type by feeding the produced data to a callback.

      This function 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 save(String, String, GError[], Object...) for more details.

      Parameters:
      saveFunc - a function that is called to save each block of data that the save routine generates.
      type - name of file format.
      error - return location for error, or NULL
      varargs - list of key-value save options
      Returns:
      whether an error was set
      Since:
      2.4

    • saveToCallbackv

      public boolean saveToCallbackv(@Nullable PixbufSaveFunc saveFunc, String type, @Nullable String @Nullable [] optionKeys, @Nullable String @Nullable [] optionValues) throws GErrorException

      Vector version of gdk_pixbuf_save_to_callback().

      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 saveToCallback(PixbufSaveFunc, String, GError[], Object...) for more details.

      Parameters:
      saveFunc - a function that is called to save each block of data that the save routine generates
      type - name of file format
      optionKeys - name of options to set
      optionValues - values for named options
      Returns:
      whether an error was set
      Throws:
      GErrorException - see GError
      Since:
      2.4

    • saveToStream

      public boolean saveToStream(OutputStream stream, String type, @Nullable Cancellable cancellable, GError[] error, Object... varargs)

      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 at the end of this call.

      Parameters:
      stream - a GOutputStream to save the pixbuf to
      type - name of file format
      cancellable - optional GCancellable object, NULL to ignore
      error - return location for error, or NULL
      varargs - list of key-value save options
      Returns:
      TRUE if the pixbuf was saved successfully, FALSE if an error was set.
      Since:
      2.14

    • saveToStreamAsync

      public void saveToStreamAsync(OutputStream stream, String type, @Nullable Cancellable cancellable, @Nullable AsyncReadyCallback callback, Object... varargs)

      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:
      stream - a GOutputStream to which to save the pixbuf
      type - name of file format
      cancellable - optional GCancellable object, NULL to ignore
      callback - a GAsyncReadyCallback to call when the pixbuf is saved
      varargs - list of key-value save options
      Since:
      2.24

    • saveToStreamv

      public boolean saveToStreamv(OutputStream stream, String type, @Nullable String @Nullable [] optionKeys, @Nullable String @Nullable [] optionValues, @Nullable Cancellable cancellable) throws GErrorException

      Saves pixbuf to an output stream.

      Supported file formats are currently "jpeg", "tiff", "png", "ico" or "bmp".

      See saveToStream(OutputStream, String, Cancellable, GError[], Object...) for more details.

      Parameters:
      stream - a GOutputStream to save the pixbuf to
      type - name of file format
      optionKeys - name of options to set
      optionValues - values for named options
      cancellable - optional GCancellable object, NULL to ignore
      Returns:
      TRUE if the pixbuf was saved successfully, FALSE if an error was set.
      Throws:
      GErrorException - see GError
      Since:
      2.36

    • saveToStreamvAsync

      public void saveToStreamvAsync(OutputStream stream, String type, @Nullable String @Nullable [] optionKeys, @Nullable String @Nullable [] optionValues, @Nullable Cancellable cancellable, @Nullable AsyncReadyCallback callback)

      Saves pixbuf to an output stream asynchronously.

      For more details see gdk_pixbuf_save_to_streamv(), 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:
      stream - a GOutputStream to which to save the pixbuf
      type - name of file format
      optionKeys - name of options to set
      optionValues - values for named options
      cancellable - optional GCancellable object, NULL to ignore
      callback - a GAsyncReadyCallback to call when the pixbuf is saved
      Since:
      2.36

    • savev

      public boolean savev(String filename, String type, @Nullable String @Nullable [] optionKeys, @Nullable String @Nullable [] optionValues) throws GErrorException

      Vector version of gdk_pixbuf_save().

      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 save(String, String, GError[], Object...) for more details.

      Parameters:
      filename - name of file to save.
      type - name of file format.
      optionKeys - name of options to set
      optionValues - values for named options
      Returns:
      whether an error was set
      Throws:
      GErrorException - see GError

    • scale

      public void scale(Pixbuf dest, int destX, int destY, int destWidth, int destHeight, double offsetX, double offsetY, double scaleX, double scaleY, InterpType interpType)

      Creates a transformation of the source image this Pixbuf by scaling by scaleX and scaleY then translating by offsetX and offsetY, then renders the rectangle (destX, destY, destWidth, destHeight) of the resulting image onto the destination image replacing the previous contents.

      Try to use gdk_pixbuf_scale_simple() first; this function is the industrial-strength power tool you can fall back to, if gdk_pixbuf_scale_simple() isn't powerful enough.

      If the source rectangle overlaps the destination rectangle on the same pixbuf, it will be overwritten during the scaling which results in rendering artifacts.

      Parameters:
      dest - the GdkPixbuf into which to render the results
      destX - the left coordinate for region to render
      destY - the top coordinate for region to render
      destWidth - the width of the region to render
      destHeight - the height of the region to render
      offsetX - the offset in the X direction (currently rounded to an integer)
      offsetY - the offset in the Y direction (currently rounded to an integer)
      scaleX - the scale factor in the X direction
      scaleY - the scale factor in the Y direction
      interpType - the interpolation type for the transformation.

    • scaleSimple

      public @Nullable Pixbuf scaleSimple(int destWidth, int destHeight, InterpType interpType)

      Create a new pixbuf containing a copy of src scaled to dest_width x dest_height.

      This function leaves src unaffected.

      The interp_type should be GDK_INTERP_NEAREST if you want maximum speed (but when scaling down GDK_INTERP_NEAREST is usually unusably ugly). The default interp_type should be GDK_INTERP_BILINEAR which offers reasonable quality and speed.

      You can scale a sub-portion of src by creating a sub-pixbuf pointing into src; see newSubpixbuf(int, int, int, int).

      If dest_width and dest_height are equal to the width and height of src, this function will return an unscaled copy of src.

      For more complicated scaling/alpha blending see scale(Pixbuf, int, int, int, int, double, double, double, double, InterpType) and composite(Pixbuf, int, int, int, int, double, double, double, double, InterpType, int).

      Parameters:
      destWidth - the width of destination image
      destHeight - the height of destination image
      interpType - the interpolation type for the transformation.
      Returns:
      the new pixbuf

    • setOption

      public boolean setOption(String key, String value)

      Attaches a key/value pair as an option to a GdkPixbuf.

      If key already exists in the list of options attached to the pixbuf, the new value is ignored and FALSE is returned.

      Parameters:
      key - a nul-terminated string.
      value - a nul-terminated string.
      Returns:
      TRUE on success
      Since:
      2.2

    • unref

      @Deprecated public void unref()
      Deprecated.
      Use g_object_unref().
      Removes a reference from a pixbuf.
      Overrides:
      unref in class GObject

    • saveUtf8

      public boolean saveUtf8(String filename, String type, GError[] error, Object... varargs)

    • savevUtf8

      public boolean savevUtf8(String filename, String type, @Nullable String @Nullable [] optionKeys, @Nullable String @Nullable [] optionValues) throws GErrorException
      Same as gdk_pixbuf_savev()
      Parameters:
      filename - name of file to save.
      type - name of file format.
      optionKeys - name of options to set
      optionValues - values for named options
      Returns:
      whether an error was set
      Throws:
      GErrorException - see GError

    • builder

      public static Pixbuf.Builder<? extends Pixbuf.Builder> builder()
      A Pixbuf.Builder object constructs a Pixbuf with the specified properties. Use the various set...() methods to set properties, and finish construction with Pixbuf.Builder.build().
      Returns:
      the builder object