







The PIL.Image Module


blend(im1, im2, alpha)  [ #PIL.Image.blend-function# ]

Creates a new image by interpolating between two input images, using
a constant alpha.


   out = image1 * (1.0 - alpha) + image2 * alpha



im1

The first image.

im2

The second image.  Must have the same mode and size as
   the first image.

alpha

The interpolation alpha factor.  If alpha is 0.0, a
   copy of the first image is returned. If alpha is 1.0, a copy of
   the second image is returned. There are no restrictions on the
   alpha value. If necessary, the result is clipped to fit into
   the allowed output range.

Returns:

An Image object.



composite(image1, image2, mask)  [ #PIL.Image.composite-function# ]

Creates a new image by interpolating between two input images,
using the mask as alpha.


image1

The first image.

image2

The second image.  Must have the same mode and
   size as the first image.

mask

A mask image.  This image can can have mode
   "1", "L", or "RGBA", and must have the same size as the
   other two images.



eval(image, function)  [ #PIL.Image.eval-function# ]

Applies the function (which should take one argument) to each pixel
in the given image. If the image has more than one band, the same
function is applied to each band. Note that the function is
evaluated once for each possible pixel value, so you cannot use
random components or other generators.


image

The input image.

function

A function object, taking one integer argument.

Returns:

An Image object.



frombuffer(mode, size, data, decoder_name="raw", *args)  [ #PIL.Image.frombuffer-function# ]

(New in 1.1.4) Creates an image memory from pixel data in a string
or byte buffer.

This function is similar to 
#PIL.Image.fromstring-functionfromstring , but uses data in
the byte buffer, where possible.  This means that changes to the
original buffer object are reflected in this image).  Not all modes
can share memory; support modes include "L", "RGBX", "RGBA", and
"CMYK".  For other modes, this function behaves like a corresponding
call to the 
fromstring function.

Note that this function decodes pixel data only, not entire images.
If you have an entire image file in a string, wrap it in a
StringIO object, and use #PIL.Image.open-functionopen  to load it.


mode

The image mode.

size

The image size.

data

An 8-bit string or other buffer object containing raw
    data for the given mode.

decoder_name

What decoder to use.

*args

Additional parameters for the given decoder.

Returns:

An Image object.



fromstring(mode, size, data, decoder_name="raw", *args)  [ #PIL.Image.fromstring-function# ]

Creates an image memory from pixel data in a string.

In its simplest form, this function takes three arguments
(mode, size, and unpacked pixel data).

You can also use any pixel decoder supported by PIL.  For more
information on available decoders, see the section 
pil-decoder.htmWriting Your Own File Decoder .

Note that this function decodes pixel data only, not entire images.
If you have an entire image in a string, wrap it in a
StringIO object, and use #PIL.Image.open-functionopen  to load it.


mode

The image mode.

size

The image size.

data

An 8-bit string containing raw data for the given mode.

decoder_name

What decoder to use.

*args

Additional parameters for the given decoder.

Returns:

An Image object.



getmodebands(mode)  [ #PIL.Image.getmodebands-function# ]

Gets a list of individual band names.  Given a mode, this function
returns a tuple containing the names of individual bands (use
#PIL.Image.getmodetype-functiongetmodetype  to get the mode used to store each individual
band.


mode

Input mode.

Returns:

A tuple containing band names.  The length of the tuple
    gives the number of bands in an image of the given mode.

Raises KeyError:
If the input mode was not a standard mode.



getmodebase(mode)  [ #PIL.Image.getmodebase-function# ]

Gets the "base" mode for given mode.  This function returns "L" for
images that contain grayscale data, and "RGB" for images that
contain color data.


mode

Input mode.

Returns:

"L" or "RGB".

Raises KeyError:
If the input mode was not a standard mode.



getmodetype(mode)  [ #PIL.Image.getmodetype-function# ]

Gets the storage type mode.  Given a mode, this function returns a
single-layer mode suitable for storing individual bands.


mode

Input mode.

Returns:

"L", "I", or "F".

Raises KeyError:
If the input mode was not a standard mode.



Image() (class) [ #PIL.Image.Image-class# ]

This class represents an image object.

For more information about this class, see #PIL.Image.Image-classThe Image Class .


init()  [ #PIL.Image.init-function# ]

Explicitly initializes the Python Imaging Library.  This function
loads all available file format drivers.


isDirectory(f)  [ #PIL.Image.isDirectory-function# ]

(Internal) Checks if an object is a string, and that it points to a
directory.


isImageType(t)  [ #PIL.Image.isImageType-function# ]

(Internal) Checks if an object is an image object.


isStringType(t)  [ #PIL.Image.isStringType-function# ]

(Internal) Checks if an object is a string.  If the current
Python version supports Unicode, this checks for both 8-bit
and Unicode strings.


isTupleType(t)  [ #PIL.Image.isTupleType-function# ]

(Internal) Checks if an object is a tuple.


merge(mode, bands)  [ #PIL.Image.merge-function# ]

Creates a new image from a number of single-band images.


mode

The mode to use for the output image.

bands

A sequence containing one single-band image for
    each band in the output image.  All bands must have the
    same size.

Returns:

An Image object.



new(mode, size, color=0)  [ #PIL.Image.new-function# ]

Creates a new image with the given mode and size.


mode

The mode to use for the new image.

size

A 2-tuple, containing (width, height) in pixels.

color

What colour to use for the image.  Default is black.
   If given, this should be a single integer or floating point value
   for single-band modes, and a tuple for multi-band modes (one value
   per band).  When creating RGB images, you can also use colour
   strings as supported by the ImageColor module.  If the colour is
   None, the image is not initialised.

Returns:

An Image object.



open(file, mode="r")  [ #PIL.Image.open-function# ]

Opens and identifies the given image file.

This is a lazy operation; this function identifies the file, but the
actual image data is not read from the file until you try to process
the data (or call the 
#PIL.Image.Image.load-methodload  method).


file

A filename (string) or a file object.  The file object
   must implement 
read, seek, and tell methods,
   and be opened in binary mode.

mode

The mode.  If given, this argument must be "r".

Returns:

An Image object.

Raises IOError:
If the file cannot be found, or the image cannot be
   opened and identified.



preinit()  [ #PIL.Image.preinit-function# ]

Explicitly loads standard file format drivers.


register_extension(id, extension)  [ #PIL.Image.register_extension-function# ]

Registers an image extension.  This function should not be
used in application code.


id

An image format identifier.

extension

An extension used for this format.



register_mime(id, mimetype)  [ #PIL.Image.register_mime-function# ]

Registers an image MIME type.  This function should not be used
in application code.


id

An image format identifier.

mimetype

The image MIME type for this format.



register_open(id, factory, accept=None)  [ #PIL.Image.register_open-function# ]

Register an image file plugin.  This function should not be used
in application code.


id

An image format identifier.

factory

An image file factory method.

accept

An optional function that can be used to quickly
   reject images having another format.



register_save(id, driver)  [ #PIL.Image.register_save-function# ]

Registers an image save function.  This function should not be
used in application code.


id

An image format identifier.

driver

A function to save images in this format.




The Image Class 


Image() (class) [ #PIL.Image.Image-class# ]

This class represents an image object.  To create Image objects, use
the appropriate factory functions.  There's hardly ever any reason
to call the Image constructor directly.


convert(mode, matrix=None)  [ #PIL.Image.Image.convert-method# ]

Returns a converted copy of this image. For the "P" mode, this
method translates pixels through the palette.  If mode is
omitted, a mode is chosen so that all information in the image
and the palette can be represented without a palette.

The current version supports all possible conversions between
"L", "RGB" and "CMYK."

When translating a colour image to black and white (mode "L"),
the library uses the ITU-R 601-2 luma transform:

L = R * 299/1000 + G * 587/1000 + B * 114/1000

When translating a greyscale image into a bilevel image (mode
"1"), all non-zero values are set to 255 (white). To use other
thresholds, use the 
#PIL.Image.Image.point-methodpoint  method.


mode

The requested mode.

matrix

An optional conversion matrix.  If given, this
   should be 4- or 16-tuple containing floating point values.

Returns:

An Image object.



copy()  [ #PIL.Image.Image.copy-method# ]

Copies this image. Use this method if you wish to paste things
into an image, but still retain the original.


Returns:

An Image object.



crop(box=None)  [ #PIL.Image.Image.crop-method# ]

Returns a rectangular region from this image. The box is a
4-tuple defining the left, upper, right, and lower pixel
coordinate.

This is a lazy operation.  Changes to the source image may or
may not be reflected in the cropped image.  To break the
connection, call the 
#PIL.Image.Image.load-methodload  method on the cropped
copy.


The

crop rectangle, as a (left, upper, right, lower)-tuple.

Returns:

An Image object.



draft(mode, size)  [ #PIL.Image.Image.draft-method# ]

Configures the image file loader so it returns a version of the
image that as closely as possible matches the given mode and
size.  For example, you can use this method to convert a colour
JPEG to greyscale while loading it, or to extract a 128x192
version from a PCD file.

Note that this method modifies the Image object in place.  If
the image has already been loaded, this method has no effect.


mode

The requested mode.

size

The requested size.



filter(filter)  [ #PIL.Image.Image.filter-method# ]

Filters this image using the given filter.  For a list of
available filters, see the 
ImageFilter module.


filter

Filter kernel.

Returns:

An Image object.



fromstring(data, decoder_name="raw", *args)  [ #PIL.Image.Image.fromstring-method# ]

Loads this image with pixel data from a string.

This method is similar to the 
#PIL.Image.fromstring-functionfromstring  function, but
loads data into this image instead of creating a new image
object.

getbands()  [ #PIL.Image.Image.getbands-method# ]

Returns a tuple containing the name of each band in this image.
For example, 
getbands on an RGB image returns ("R", "G", "B").


Returns:

A tuple containing band names.



getbbox()  [ #PIL.Image.Image.getbbox-method# ]

Calculates the bounding box of the non-zero regions in the
image.


Returns:

The bounding box is returned as a 4-tuple defining the
   left, upper, right, and lower pixel coordinate. If the image
   is completely empty, this method returns None.



getcolors(maxcolors=256)  [ #PIL.Image.Image.getcolors-method# ]

Returns a list of colors used in this image.


maxcolors

Maximum number of colors.  If this number is
   exceeded, this method returns None.  The default limit is
   256 colors.

Returns:

An unsorted list of (count, pixel) values.



getdata(band=None)  [ #PIL.Image.Image.getdata-method# ]

Returns the contents of this image as a sequence object
containing pixel values.  The sequence object is flattened, so
that values for line one follow directly after the values of
line zero, and so on.

Note that the sequence object returned by this method is an
internal PIL data type, which only supports certain sequence
operations.  To convert it to an ordinary sequence (e.g. for
printing), use 
list(im.getdata()).


band

What band to return.  The default is to return
   all bands.  To return a single band, pass in the index
   value (e.g. 0 to get the "R" band from an "RGB" image).

Returns:

A sequence-like object.



getextrema()  [ #PIL.Image.Image.getextrema-method# ]

Gets the the minimum and maximum pixel values for each band in
the image.


Returns:

For a single-band image, a 2-tuple containing the
   minimum and maximum pixel value.  For a multi-band image,
   a tuple containing one 2-tuple for each band.



getim()  [ #PIL.Image.Image.getim-method# ]

Returns a PyCObject that points to the internal image memory.


Returns:

A PyCObject object.



getpalette()  [ #PIL.Image.Image.getpalette-method# ]

Returns the image palette as a list.


Returns:

A list of color values [r, g, b, ...], or None if the
   image has no palette.



getpixel(xy)  [ #PIL.Image.Image.getpixel-method# ]

Returns the pixel value at a given position.


xy

The coordinate, given as (x, y).

Returns:

The pixel value.  If the image is a multi-layer image,
   this method returns a tuple.



getprojection()  [ #PIL.Image.Image.getprojection-method# ]

Returns the horizontal and vertical projection.


Returns:

Two sequences, indicating where there are non-zero
    pixels along the X-axis and the Y-axis, respectively.



histogram(mask=None)  [ #PIL.Image.Image.histogram-method# ]

Returns a histogram for the image. The histogram is returned as
a list of pixel counts, one for each pixel value in the source
image. If the image has more than one band, the histograms for
all bands are concatenated (for example, the histogram for an
"RGB" image contains 768 values).

A bilevel image (mode "1") is treated as a greyscale ("L") image
by this method.

If a mask is provided, the method returns a histogram for those
parts of the image where the mask image is non-zero. The mask
image must have the same size as the image, and be either a
bi-level image (mode "1") or a greyscale image ("L").


mask

An optional mask.

Returns:

A list containing pixel counts.



load()  [ #PIL.Image.Image.load-method# ]

Allocates storage for the image and loads the pixel data.  In
normal cases, you don't need to call this method, since the
Image class automatically loads an opened image when it is
accessed for the first time.


offset(xoffset, yoffset=None)  [ #PIL.Image.Image.offset-method# ]

(Deprecated) Returns a copy of the image where the data has been
offset by the given distances. Data wraps around the edges. If
yoffset is omitted, it is assumed to be equal to xoffset.

This method is deprecated. New code should use the 
offset
function in the 
ImageChops module.


xoffset

The horizontal distance.

yoffset

The vertical distance.  If omitted, both
   distances are set to the same value.

Returns:

An Image object.



paste(im, box=None, mask=None)  [ #PIL.Image.Image.paste-method# ]

Pastes another image into this image. The box argument is either
a 2-tuple giving the upper left corner, a 4-tuple defining the
left, upper, right, and lower pixel coordinate, or None (same as
(0, 0)).  If a 4-tuple is given, the size of the pasted image
must match the size of the region.

If the modes don't match, the pasted image is converted to the
mode of this image (see the 
#PIL.Image.Image.convert-methodconvert  method for
details).

Instead of an image, the source can be a integer or tuple
containing pixel values.  The method then fills the region
with the given colour.  When creating RGB images, you can
also use colour strings as supported by the ImageColor module.

If a mask is given, this method updates only the regions
indicated by the mask.  You can use either "1", "L" or "RGBA"
images (in the latter case, the alpha band is used as mask).
Where the mask is 255, the given image is copied as is.  Where
the mask is 0, the current value is preserved.  Intermediate
values can be used for transparency effects.

Note that if you paste an "RGBA" image, the alpha band is
ignored.  You can work around this by using the same image as
both source image and mask.


im

Source image or pixel value (integer or tuple).

box

An optional 4-tuple giving the region to paste into.
   If a 2-tuple is used instead, it's treated as the upper left
   corner.  If omitted or None, the source is pasted into the
   upper left corner.
   

   If an image is given as the second argument and there is no
   third, the box defaults to (0, 0), and the second argument
   is interpreted as a mask image.

mask

An optional mask image.

Returns:

An Image object.



point(lut, mode=None)  [ #PIL.Image.Image.point-method# ]

Maps this image through a lookup table or function.


lut

A lookup table, containing 256 values per band in the
   image. A function can be used instead, it should take a single
   argument. The function is called once for each possible pixel
   value, and the resulting table is applied to all bands of the
   image.

mode

Output mode (default is same as input).  In the
   current version, this can only be used if the source image
   has mode "L" or "P", and the output has mode "1".

Returns:

An Image object.



putalpha(alpha)  [ #PIL.Image.Image.putalpha-method# ]

Adds or replaces the alpha layer in this image.  If the image
does not have an alpha layer, it's converted to "LA" or "RGBA".
The new layer must be either "L" or "1".


im

The new alpha layer.  This can either be an "L" or "1"
   image having the same size as this image, or an integer or
   other color value.



putdata(data, scale=1.0, offset=0.0)  [ #PIL.Image.Image.putdata-method# ]

Copies pixel data to this image.  This method copies data from a
sequence object into the image, starting at the upper left
corner (0, 0), and continuing until either the image or the
sequence ends.  The scale and offset values are used to adjust
the sequence values: 
pixel = value*scale + offset.


data

A sequence object.

scale

An optional scale value.  The default is 1.0.

offset

An optional offset value.  The default is 0.0.



putpalette(data)  [ #PIL.Image.Image.putpalette-method# ]

Attaches a palette to this image.  The image must be a "P" or
"L" image, and the palette sequence must contain 768 integer
values, where each group of three values represent the red,
green, and blue values for the corresponding pixel
index. Instead of an integer sequence, you can use an 8-bit
string.


data

A palette sequence (either a list or a string).



putpixel(xy, value)  [ #PIL.Image.Image.putpixel-method# ]

Modifies the pixel at the given position. The colour is given as
a single numerical value for single-band images, and a tuple for
multi-band images.

Note that this method is relatively slow.  For more extensive
changes, use 
#PIL.Image.Image.paste-methodpaste  or the ImageDraw module
instead.


xy

The pixel coordinate, given as (x, y).

value

The pixel value.



resize(size, filter=NEAREST)  [ #PIL.Image.Image.resize-method# ]

Returns a resized copy of this image.


size

The requested size in pixels, as a 2-tuple:
   (width, height).

filter

An optional resampling filter.  This can be
   one of 
NEAREST (use nearest neighbour), BILINEAR
   (linear interpolation in a 2x2 environment), 
BICUBIC
   (cubic spline interpolation in a 4x4 environment), or
   
ANTIALIAS (a high-quality downsampling filter).
   If omitted, or if the image has mode "1" or "P", it is
   set 
NEAREST.

Returns:

An Image object.



rotate(angle, filter=NEAREST)  [ #PIL.Image.Image.rotate-method# ]

Returns a rotated copy of this image.  This method returns a
copy of this image, rotated the given number of degrees counter
clockwise around its centre.


angle

In degrees counter clockwise.

filter

An optional resampling filter.  This can be
   one of 
NEAREST (use nearest neighbour), BILINEAR
   (linear interpolation in a 2x2 environment), or 
BICUBIC
   (cubic spline interpolation in a 4x4 environment).
   If omitted, or if the image has mode "1" or "P", it is
   set 
NEAREST.

Returns:

An Image object.



save(file, format=None, **options)  [ #PIL.Image.Image.save-method# ]

Saves this image under the given filename.  If no format is
specified, the format to use is determined from the filename
extension, if possible.

Keyword options can be used to provide additional instructions
to the writer. If a writer doesn't recognise an option, it is
silently ignored. The available options are described later in
this handbook.

You can use a file object instead of a filename. In this case,
you must always specify the format. The file object must
implement the 
seek, tell, and write
methods, and be opened in binary mode.


file

File name or file object.

format

Optional format override.  If omitted, the
   format to use is determined from the filename extension.
   If a file object was used instead of a filename, this
   parameter should always be used.

**options

Extra parameters to the image writer.

Returns:

None

Raises KeyError:
If the output format could not be determined
   from the file name.  Use the format option to solve this.

Raises IOError:
If the file could not be written.  The file
   may have been created, and may contain partial data.



seek(frame)  [ #PIL.Image.Image.seek-method# ]

Seeks to the given frame in this sequence file. If you seek
beyond the end of the sequence, the method raises an
EOFError exception. When a sequence file is opened, the
library automatically seeks to frame 0.

Note that in the current version of the library, most sequence
formats only allows you to seek to the next frame.


frame

Frame number, starting at 0.

Raises EOFError:
If the call attempts to seek beyond the end
    of the sequence.



show(title=None)  [ #PIL.Image.Image.show-method# ]

Displays this image. This method is mainly intended for
debugging purposes.

On Unix platforms, this method saves the image to a temporary
PPM file, and calls the 
xv utility.

On Windows, it saves the image to a temporary BMP file, and uses
the standard BMP display utility to show it (usually Paint).


title

Optional title to use for the image window,
   where possible.



split()  [ #PIL.Image.Image.split-method# ]

Split this image into individual bands. This method returns a
tuple of individual image bands from an image. For example,
splitting an "RGB" image creates three new images each
containing a copy of one of the original bands (red, green,
blue).


Returns:

A tuple containing bands.



tell()  [ #PIL.Image.Image.tell-method# ]

Returns the current frame number.


Returns:

Frame number, starting with 0.



thumbnail(size, resample=NEAREST)  [ #PIL.Image.Image.thumbnail-method# ]

Make this image into a thumbnail.  This method modifies the
image to contain a thumbnail version of itself, no larger than
the given size.  This method calculates an appropriate thumbnail
size to preserve the aspect of the image, calls the 
#PIL.Image.Image.draft-methoddraft  method to configure the file reader (where
applicable), and finally resizes the image.

Note that the bilinear and bicubic filters in the current
version of PIL are not well-suited for thumbnail generation.
You should use 
ANTIALIAS unless speed is much more
important than quality.

Also note that this function modifies the Image object in place.
If you need to use the full resolution image as well, apply this
method to a 
#PIL.Image.Image.copy-methodcopy  of the original image.


size

Requested size.

resample

Optional resampling filter.  This can be one
   of 
NEAREST, BILINEAR, BICUBIC, or
   
ANTIALIAS (best quality).  If omitted, it defaults
   to 
NEAREST (this will be changed to ANTIALIAS in a
   future version).

Returns:

None



tobitmap(name="image")  [ #PIL.Image.Image.tobitmap-method# ]

Returns the image converted to an X11 bitmap.  This method
only works for mode "1" images.


name

The name prefix to use for the bitmap variables.

Returns:

A string containing an X11 bitmap.

Raises ValueError:
If the mode is not "1"



tostring(encoder_name="raw", *args)  [ #PIL.Image.Image.tostring-method# ]

Returns a string containing pixel data.


encoder_name

What encoder to use.  The default is to
   use the standard "raw" encoder.

*args

Extra arguments to the encoder.

Returns:

An 8-bit string.



transform(size, method, data, resample=NEAREST)  [ #PIL.Image.Image.transform-method# ]

Transforms this image.  This method creates a new image with the
given size, and the same mode as the original, and copies data
to the new image using the given transform.


size

The output size.

method

The transformation method.  This is one of
  
EXTENT (cut out a rectangular subregion), AFFINE
  (affine transform), 
PERSPECTIVE (perspective
  transform), 
QUAD (map a quadrilateral to a
  rectangle), or 
MESH (map a number of source quadrilaterals
  in one operation).

data

Extra data to the transformation method.

resample

Optional resampling filter.  It can be one of
   
NEAREST (use nearest neighbour), BILINEAR
   (linear interpolation in a 2x2 environment), or
   
BICUBIC (cubic spline interpolation in a 4x4
   environment). If omitted, or if the image has mode
   "1" or "P", it is set to 
NEAREST.

Returns:

An Image object.



transpose(method)  [ #PIL.Image.Image.transpose-method# ]

Returns a flipped or rotated copy of this image.


method

One of 
FLIP_LEFT_RIGHT, FLIP_TOP_BOTTOM,
ROTATE_90, ROTATE_180, or ROTATE_270.



verify()  [ #PIL.Image.Image.verify-method# ]

Verifies the contents of a file. For data read from a file, this
method attempts to determine if the file is broken, without
actually decoding the image data.  If this method finds any
problems, it raises suitable exceptions.  If you need to load
the image after using this method, you must reopen the image
file.




