Image Module

The Image module provides a class with the same name which is used to represent a PIL image. The module also provides a number of factory functions, including functions to load images from files, and to create new images.

Examples

Open, rotate, and display an image (using the default viewer)

The following script loads an image, rotates it 45 degrees, and displays it using an external viewer (usually xv on Unix, and the Paint program on Windows).

from PIL import Image
with Image.open("hopper.jpg") as im:
    im.rotate(45).show()

Create thumbnails

The following script creates nice thumbnails of all JPEG images in the current directory preserving aspect ratios with 128x128 max resolution.

from PIL import Image
import glob, os

size = 128, 128

for infile in glob.glob("*.jpg"):
    file, ext = os.path.splitext(infile)
    with Image.open(infile) as im:
        im.thumbnail(size)
        im.save(file + ".thumbnail", "JPEG")

Functions

PIL.Image.open(fp, mode='r', formats=None)[source]

Opens and identifies the given image file.

This is a lazy operation; this function identifies the file, but the file remains open and the actual image data is not read from the file until you try to process the data (or call the load() method). See new(). See File Handling in Pillow.

Parameters:
  • fp – A filename (string), pathlib.Path object or a file object. The file object must implement file.read, file.seek, and file.tell methods, and be opened in binary mode.

  • mode – The mode. If given, this argument must be “r”.

  • formats – A list or tuple of formats to attempt to load the file in. This can be used to restrict the set of formats checked. Pass None to try all supported formats. You can print the set of available formats by running python3 -m PIL or using the PIL.features.pilinfo() function.

Returns:

An Image object.

Raises:

Warning

To protect against potential DOS attacks caused by “decompression bombs” (i.e. malicious files which decompress into a huge amount of data and are designed to crash or cause disruption by using up a lot of memory), Pillow will issue a DecompressionBombWarning if the number of pixels in an image is over a certain limit, MAX_IMAGE_PIXELS.

This threshold can be changed by setting MAX_IMAGE_PIXELS. It can be disabled by setting Image.MAX_IMAGE_PIXELS = None.

If desired, the warning can be turned into an error with warnings.simplefilter('error', Image.DecompressionBombWarning) or suppressed entirely with warnings.simplefilter('ignore', Image.DecompressionBombWarning). See also the logging documentation to have warnings output to the logging facility instead of stderr.

If the number of pixels is greater than twice MAX_IMAGE_PIXELS, then a DecompressionBombError will be raised instead.

Image processing

PIL.Image.alpha_composite(im1, im2)[source]

Alpha composite im2 over im1.

Parameters:
  • im1 – The first image. Must have mode RGBA.

  • im2 – The second image. Must have mode RGBA, and the same size as the first image.

Returns:

An Image object.

PIL.Image.blend(im1, im2, alpha)[source]

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

out = image1 * (1.0 - alpha) + image2 * alpha
Parameters:
  • 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.

PIL.Image.composite(image1, image2, mask)[source]

Create composite image by blending images using a transparency mask.

Parameters:
  • 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 have mode “1”, “L”, or “RGBA”, and must have the same size as the other two images.

PIL.Image.eval(image, *args)[source]

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.

Parameters:
  • image – The input image.

  • function – A function object, taking one integer argument.

Returns:

An Image object.

PIL.Image.merge(mode, bands)[source]

Merge a set of single band images into a new multiband image.

Parameters:
  • mode – The mode to use for the output image. See: Modes.

  • 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.

Constructing images

PIL.Image.new(mode, size, color=0)[source]

Creates a new image with the given mode and size.

Parameters:
  • mode – The mode to use for the new image. See: Modes.

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

  • color – What color 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 color strings as supported by the ImageColor module. If the color is None, the image is not initialised.

Returns:

An Image object.

PIL.Image.fromarray(obj, mode=None)[source]

Creates an image memory from an object exporting the array interface (using the buffer protocol).

If obj is not contiguous, then the tobytes method is called and frombuffer() is used.

If you have an image in NumPy:

from PIL import Image
import numpy as np
im = Image.open("hopper.jpg")
a = np.asarray(im)

Then this can be used to convert it to a Pillow image:

im = Image.fromarray(a)
Parameters:
  • obj – Object with array interface

  • mode

    Optional mode to use when reading obj. Will be determined from type if None.

    This will not be used to convert the data after reading, but will be used to change how the data is read:

    from PIL import Image
    import numpy as np
    a = np.full((1, 1), 300)
    im = Image.fromarray(a, mode="L")
    im.getpixel((0, 0))  # 44
    im = Image.fromarray(a, mode="RGB")
    im.getpixel((0, 0))  # (44, 1, 0)
    

    See: Modes for general information about modes.

Returns:

An image object.

New in version 1.1.6.

PIL.Image.frombytes(mode, size, data, decoder_name='raw', *args)[source]

Creates a copy of an image memory from pixel data in a buffer.

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 Writing Your Own File Codec.

Note that this function decodes pixel data only, not entire images. If you have an entire image in a string, wrap it in a BytesIO object, and use open() to load it.

Parameters:
  • mode – The image mode. See: Modes.

  • size – The image size.

  • data – A byte buffer containing raw data for the given mode.

  • decoder_name – What decoder to use.

  • args – Additional parameters for the given decoder.

Returns:

An Image object.

PIL.Image.frombuffer(mode, size, data, decoder_name='raw', *args)[source]

Creates an image memory referencing pixel data in a byte buffer.

This function is similar to frombytes(), 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; supported modes include “L”, “RGBX”, “RGBA”, and “CMYK”.

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 BytesIO object, and use open() to load it.

In the current version, the default parameters used for the “raw” decoder differs from that used for frombytes(). This is a bug, and will probably be fixed in a future release. The current release issues a warning if you do this; to disable the warning, you should provide the full set of parameters. See below for details.

Parameters:
  • mode – The image mode. See: Modes.

  • size – The image size.

  • data – A bytes or other buffer object containing raw data for the given mode.

  • decoder_name – What decoder to use.

  • args

    Additional parameters for the given decoder. For the default encoder (“raw”), it’s recommended that you provide the full set of parameters:

    frombuffer(mode, size, data, "raw", mode, 0, 1)
    

Returns:

An Image object.

New in version 1.1.4.

Generating images

PIL.Image.effect_mandelbrot(size, extent, quality)[source]

Generate a Mandelbrot set covering the given extent.

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

  • extent – The extent to cover, as a 4-tuple: (x0, y0, x1, y1).

  • quality – Quality.

PIL.Image.effect_noise(size, sigma)[source]

Generate Gaussian noise centered around 128.

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

  • sigma – Standard deviation of noise.

PIL.Image.linear_gradient(mode)[source]

Generate 256x256 linear gradient from black to white, top to bottom.

Parameters:

mode – Input mode.

PIL.Image.radial_gradient(mode)[source]

Generate 256x256 radial gradient from black to white, centre to edge.

Parameters:

mode – Input mode.

Registering plugins

Note

These functions are for use by plugin authors. Application authors can ignore them.

PIL.Image.register_open(id, factory, accept=None)[source]

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

Parameters:
  • 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.

PIL.Image.register_mime(id, mimetype)[source]

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

Parameters:
  • id – An image format identifier.

  • mimetype – The image MIME type for this format.

PIL.Image.register_save(id, driver)[source]

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

Parameters:
  • id – An image format identifier.

  • driver – A function to save images in this format.

PIL.Image.register_save_all(id, driver)[source]

Registers an image function to save all the frames of a multiframe format. This function should not be used in application code.

Parameters:
  • id – An image format identifier.

  • driver – A function to save images in this format.

PIL.Image.register_extension(id, extension)[source]

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

Parameters:
  • id – An image format identifier.

  • extension – An extension used for this format.

PIL.Image.register_extensions(id, extensions)[source]

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

Parameters:
  • id – An image format identifier.

  • extensions – A list of extensions used for this format.

PIL.Image.registered_extensions()[source]

Returns a dictionary containing all file extensions belonging to registered plugins

PIL.Image.register_decoder(name, decoder)[source]

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

Parameters:
  • name – The name of the decoder

  • decoder – A callable(mode, args) that returns an ImageFile.PyDecoder object

New in version 4.1.0.

PIL.Image.register_encoder(name, encoder)[source]

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

Parameters:
  • name – The name of the encoder

  • encoder – A callable(mode, args) that returns an ImageFile.PyEncoder object

New in version 4.1.0.

The Image Class

class PIL.Image.Image[source]

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.

An instance of the Image class has the following methods. Unless otherwise stated, all methods return a new instance of the Image class, holding the resulting image.

Image.alpha_composite(im, dest=(0, 0), source=(0, 0))[source]

‘In-place’ analog of Image.alpha_composite. Composites an image onto this image.

Parameters:
  • im – image to composite over this one

  • dest – Optional 2 tuple (left, top) specifying the upper left corner in this (destination) image.

  • source – Optional 2 (left, top) tuple for the upper left corner in the overlay source image, or 4 tuple (left, top, right, bottom) for the bounds of the source rectangle

Performance Note: Not currently implemented in-place in the core layer.

Image.apply_transparency()[source]

If a P mode image has a “transparency” key in the info dictionary, remove the key and instead apply the transparency to the palette. Otherwise, the image is unchanged.

Image.convert(mode=None, matrix=None, dither=None, palette=Palette.WEB, colors=256)[source]

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”. The matrix argument only supports “L” and “RGB”.

When translating a color image to greyscale (mode “L”), the library uses the ITU-R 601-2 luma transform:

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

The default method of converting a greyscale (“L”) or “RGB” image into a bilevel (mode “1”) image uses Floyd-Steinberg dither to approximate the original image luminosity levels. If dither is None, all values larger than 127 are set to 255 (white), all other values to 0 (black). To use other thresholds, use the point() method.

When converting from “RGBA” to “P” without a matrix argument, this passes the operation to quantize(), and dither and palette are ignored.

When converting from “PA”, if an “RGBA” palette is present, the alpha channel from the image will be used instead of the values from the palette.

Parameters:
  • mode – The requested mode. See: Modes.

  • matrix – An optional conversion matrix. If given, this should be 4- or 12-tuple containing floating point values.

  • dither – Dithering method, used when converting from mode “RGB” to “P” or from “RGB” or “L” to “1”. Available methods are Dither.NONE or Dither.FLOYDSTEINBERG (default). Note that this is not used when matrix is supplied.

  • palette – Palette to use when converting from mode “RGB” to “P”. Available palettes are Palette.WEB or Palette.ADAPTIVE.

  • colors – Number of colors to use for the Palette.ADAPTIVE palette. Defaults to 256.

Return type:

Image

Returns:

An Image object.

The following example converts an RGB image (linearly calibrated according to ITU-R 709, using the D65 luminant) to the CIE XYZ color space:

rgb2xyz = (
    0.412453, 0.357580, 0.180423, 0,
    0.212671, 0.715160, 0.072169, 0,
    0.019334, 0.119193, 0.950227, 0)
out = im.convert("RGB", rgb2xyz)
Image.copy()[source]

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

Return type:

Image

Returns:

An Image object.

Image.crop(box=None)[source]

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

Note: Prior to Pillow 3.4.0, this was a lazy operation.

Parameters:

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

Return type:

Image

Returns:

An Image object.

This crops the input image with the provided coordinates:

from PIL import Image

with Image.open("hopper.jpg") as im:

    # The crop method from the Image module takes four coordinates as input.
    # The right can also be represented as (left+width)
    # and lower can be represented as (upper+height).
    (left, upper, right, lower) = (20, 20, 100, 100)

    # Here the image "im" is cropped and assigned to new variable im_crop
    im_crop = im.crop((left, upper, right, lower))
Image.draft(mode, size)[source]

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 color JPEG to greyscale while loading it.

If any changes are made, returns a tuple with the chosen mode and box with coordinates of the original image within the altered one.

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

Note: This method is not implemented for most images. It is currently implemented only for JPEG and MPO images.

Parameters:
  • mode – The requested mode.

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

Image.effect_spread(distance)[source]

Randomly spread pixels in an image.

Parameters:

distance – Distance to spread pixels.

Image.entropy(mask=None, extrema=None)[source]

Calculates and returns the entropy for the image.

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

If a mask is provided, the method employs the 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”).

Parameters:
  • mask – An optional mask.

  • extrema – An optional tuple of manually-specified extrema.

Returns:

A float value representing the image entropy

Image.filter(filter)[source]

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

Parameters:

filter – Filter kernel.

Returns:

An Image object.

This blurs the input image using a filter from the ImageFilter module:

from PIL import Image, ImageFilter

with Image.open("hopper.jpg") as im:

    # Blur the input image using the filter ImageFilter.BLUR
    im_blurred = im.filter(filter=ImageFilter.BLUR)
Image.frombytes(data, decoder_name='raw', *args)[source]

Loads this image with pixel data from a bytes object.

This method is similar to the frombytes() function, but loads data into this image instead of creating a new image object.

Image.getbands()[source]

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.

Return type:

tuple

This helps to get the bands of the input image:

from PIL import Image

with Image.open("hopper.jpg") as im:
    print(im.getbands())  # Returns ('R', 'G', 'B')
Image.getbbox()[source]

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. See Coordinate System. If the image is completely empty, this method returns None.

This helps to get the bounding box coordinates of the input image:

from PIL import Image

with Image.open("hopper.jpg") as im:
    print(im.getbbox())
    # Returns four coordinates in the format (left, upper, right, lower)
Image.getchannel(channel)[source]

Returns an image containing a single channel of the source image.

Parameters:

channel – What channel to return. Could be index (0 for “R” channel of “RGB”) or channel name (“A” for alpha channel of “RGBA”).

Returns:

An image in “L” mode.

New in version 4.3.0.

Image.getcolors(maxcolors=256)[source]

Returns a list of colors used in this image.

The colors will be in the image’s mode. For example, an RGB image will return a tuple of (red, green, blue) color values, and a P image will return the index of the color in the palette.

Parameters:

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.

Image.getdata(band=None)[source]

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()).

Parameters:

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.

Image.getexif()[source]
Image.getextrema()[source]

Gets 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.

Image.getpalette(rawmode='RGB')[source]

Returns the image palette as a list.

Parameters:

rawmode

The mode in which to return the palette. None will return the palette in its current mode.

New in version 9.1.0.

Returns:

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

Image.getpixel(xy)[source]

Returns the pixel value at a given position.

Parameters:

xy – The coordinate, given as (x, y). See Coordinate System.

Returns:

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

Image.getprojection()[source]

Get projection to x and y axes

Returns:

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

Image.histogram(mask=None, extrema=None)[source]

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. Counts are grouped into 256 bins for each band, even if the image has more than 8 bits per band. 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”).

Parameters:
  • mask – An optional mask.

  • extrema – An optional tuple of manually-specified extrema.

Returns:

A list containing pixel counts.

Image.paste(im, box=None, mask=None)[source]

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)). See Coordinate System. 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 convert() 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 color. When creating RGB images, you can also use color 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”, “LA”, “RGBA” or “RGBa” images (if present, 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 will mix the two images together, including their alpha channels if they have them.

See alpha_composite() if you want to combine images with respect to their alpha channels.

Parameters:
  • 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.

Image.point(lut, mode=None)[source]

Maps this image through a lookup table or function.

Parameters:
  • lut

    A lookup table, containing 256 (or 65536 if self.mode==”I” and mode == “L”) 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.

    It may also be an ImagePointHandler object:

    class Example(Image.ImagePointHandler):
      def point(self, data):
        # Return result
    

  • 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” or the source image mode is “I” and the output mode is “L”.

Returns:

An Image object.

Image.putalpha(alpha)[source]

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”.

Parameters:

alpha – 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.

Image.putdata(data, scale=1.0, offset=0.0)[source]

Copies pixel data from a flattened sequence object into the image. The values should start at the upper left corner (0, 0), continue to the end of the line, followed directly by the first value of the second line, and so on. Data will be read until either the image or the sequence ends. The scale and offset values are used to adjust the sequence values: pixel = value*scale + offset.

Parameters:
  • data – A flattened sequence object.

  • scale – An optional scale value. The default is 1.0.

  • offset – An optional offset value. The default is 0.0.

Image.putpalette(data, rawmode='RGB')[source]

Attaches a palette to this image. The image must be a “P”, “PA”, “L” or “LA” image.

The palette sequence must contain at most 256 colors, made up of one integer value for each channel in the raw mode. For example, if the raw mode is “RGB”, then it can contain at most 768 values, made up of red, green and blue values for the corresponding pixel index in the 256 colors. If the raw mode is “RGBA”, then it can contain at most 1024 values, containing red, green, blue and alpha values.

Alternatively, an 8-bit string may be used instead of an integer sequence.

Parameters:
  • data – A palette sequence (either a list or a string).

  • rawmode – The raw mode of the palette. Either “RGB”, “RGBA”, or a mode that can be transformed to “RGB” or “RGBA” (e.g. “R”, “BGR;15”, “RGBA;L”).

Image.putpixel(xy, value)[source]

Modifies the pixel at the given position. The color is given as a single numerical value for single-band images, and a tuple for multi-band images. In addition to this, RGB and RGBA tuples are accepted for P and PA images.

Note that this method is relatively slow. For more extensive changes, use paste() or the ImageDraw module instead.

See:

Parameters:
  • xy – The pixel coordinate, given as (x, y). See Coordinate System.

  • value – The pixel value.

Image.quantize(colors=256, method=None, kmeans=0, palette=None, dither=Dither.FLOYDSTEINBERG)[source]

Convert the image to ‘P’ mode with the specified number of colors.

Parameters:
Returns:

A new image

Image.reduce(factor, box=None)[source]

Returns a copy of the image reduced factor times. If the size of the image is not dividable by factor, the resulting size will be rounded up.

Parameters:
  • factor – A greater than 0 integer or tuple of two integers for width and height separately.

  • box – An optional 4-tuple of ints providing the source image region to be reduced. The values must be within (0, 0, width, height) rectangle. If omitted or None, the entire source is used.

Image.remap_palette(dest_map, source_palette=None)[source]

Rewrites the image to reorder the palette.

Parameters:
  • dest_map – A list of indexes into the original palette. e.g. [1,0] would swap a two item palette, and list(range(256)) is the identity transform.

  • source_palette – Bytes or None.

Returns:

An Image object.

Image.resize(size, resample=None, box=None, reducing_gap=None)[source]

Returns a resized copy of this image.

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

  • resample – An optional resampling filter. This can be one of Resampling.NEAREST, Resampling.BOX, Resampling.BILINEAR, Resampling.HAMMING, Resampling.BICUBIC or Resampling.LANCZOS. If the image has mode “1” or “P”, it is always set to Resampling.NEAREST. If the image mode specifies a number of bits, such as “I;16”, then the default filter is Resampling.NEAREST. Otherwise, the default filter is Resampling.BICUBIC. See: Filters.

  • box – An optional 4-tuple of floats providing the source image region to be scaled. The values must be within (0, 0, width, height) rectangle. If omitted or None, the entire source is used.

  • reducing_gap – Apply optimization by resizing the image in two steps. First, reducing the image by integer times using reduce(). Second, resizing using regular resampling. The last step changes size no less than by reducing_gap times. reducing_gap may be None (no first step is performed) or should be greater than 1.0. The bigger reducing_gap, the closer the result to the fair resampling. The smaller reducing_gap, the faster resizing. With reducing_gap greater or equal to 3.0, the result is indistinguishable from fair resampling in most cases. The default value is None (no optimization).

Returns:

An Image object.

This resizes the given image from (width, height) to (width/2, height/2):

from PIL import Image

with Image.open("hopper.jpg") as im:

    # Provide the target width and height of the image
    (width, height) = (im.width // 2, im.height // 2)
    im_resized = im.resize((width, height))
Image.rotate(angle, resample=Resampling.NEAREST, expand=0, center=None, translate=None, fillcolor=None)[source]

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.

Parameters:
  • angle – In degrees counter clockwise.

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

  • expand – Optional expansion flag. If true, expands the output image to make it large enough to hold the entire rotated image. If false or omitted, make the output image the same size as the input image. Note that the expand flag assumes rotation around the center and no translation.

  • center – Optional center of rotation (a 2-tuple). Origin is the upper left corner. Default is the center of the image.

  • translate – An optional post-rotate translation (a 2-tuple).

  • fillcolor – An optional color for area outside the rotated image.

Returns:

An Image object.

This rotates the input image by theta degrees counter clockwise:

from PIL import Image

with Image.open("hopper.jpg") as im:

    # Rotate the image by 60 degrees counter clockwise
    theta = 60
    # Angle is in degrees counter clockwise
    im_rotated = im.rotate(angle=theta)
Image.save(fp, format=None, **params)[source]

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 in the image format documentation for each writer.

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.

Parameters:
  • fp – A filename (string), pathlib.Path object 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.

  • params – Extra parameters to the image writer.

Returns:

None

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

  • OSError – If the file could not be written. The file may have been created, and may contain partial data.

Image.seek(frame)[source]

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.

See tell().

If defined, n_frames refers to the number of available frames.

Parameters:

frame – Frame number, starting at 0.

Raises:

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

Image.show(title=None)[source]

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

This method calls PIL.ImageShow.show() internally. You can use PIL.ImageShow.register() to override its default behaviour.

The image is first saved to a temporary file. By default, it will be in PNG format.

On Unix, the image is then opened using the display, eog or xv utility, depending on which one can be found.

On macOS, the image is opened with the native Preview application.

On Windows, the image is opened with the standard PNG display utility.

Parameters:

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

Image.split()[source]

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).

If you need only one band, getchannel() method can be more convenient and faster.

Returns:

A tuple containing bands.

Image.tell()[source]

Returns the current frame number. See seek().

If defined, n_frames refers to the number of available frames.

Returns:

Frame number, starting with 0.

Image.thumbnail(size, resample=Resampling.BICUBIC, reducing_gap=2.0)[source]

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 draft() method to configure the file reader (where applicable), and finally resizes the image.

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 copy() of the original image.

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

  • resample – Optional resampling filter. This can be one of Resampling.NEAREST, Resampling.BOX, Resampling.BILINEAR, Resampling.HAMMING, Resampling.BICUBIC or Resampling.LANCZOS. If omitted, it defaults to Resampling.BICUBIC. (was Resampling.NEAREST prior to version 2.5.0). See: Filters.

  • reducing_gap – Apply optimization by resizing the image in two steps. First, reducing the image by integer times using reduce() or draft() for JPEG images. Second, resizing using regular resampling. The last step changes size no less than by reducing_gap times. reducing_gap may be None (no first step is performed) or should be greater than 1.0. The bigger reducing_gap, the closer the result to the fair resampling. The smaller reducing_gap, the faster resizing. With reducing_gap greater or equal to 3.0, the result is indistinguishable from fair resampling in most cases. The default value is 2.0 (very close to fair resampling while still being faster in many cases).

Returns:

None

Image.tobitmap(name='image')[source]

Returns the image converted to an X11 bitmap.

Note

This method only works for mode “1” images.

Parameters:

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”

Image.tobytes(encoder_name='raw', *args)[source]

Return image as a bytes object.

Warning

This method returns the raw image data from the internal storage. For compressed image data (e.g. PNG, JPEG) use save(), with a BytesIO parameter for in-memory data.

Parameters:
  • encoder_name

    What encoder to use. The default is to use the standard “raw” encoder.

    A list of C encoders can be seen under codecs section of the function array in _imaging.c. Python encoders are registered within the relevant plugins.

  • args – Extra arguments to the encoder.

Returns:

A bytes object.

Image.transform(size, method, data=None, resample=Resampling.NEAREST, fill=1, fillcolor=None)[source]

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.

Parameters:
  • size – The output size in pixels, as a 2-tuple: (width, height).

  • method

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

    It may also be an ImageTransformHandler object:

    class Example(Image.ImageTransformHandler):
        def transform(self, size, data, resample, fill=1):
            # Return result
    

    It may also be an object with a method.getdata method that returns a tuple supplying new method and data values:

    class Example:
        def getdata(self):
            method = Image.Transform.EXTENT
            data = (0, 0, 100, 100)
            return method, data
    

  • data – Extra data to the transformation method.

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

  • fill – If method is an ImageTransformHandler object, this is one of the arguments passed to it. Otherwise, it is unused.

  • fillcolor – Optional fill color for the area outside the transform in the output image.

Returns:

An Image object.

Image.transpose(method)[source]

Transpose image (flip or rotate in 90 degree steps)

Parameters:

method – One of Transpose.FLIP_LEFT_RIGHT, Transpose.FLIP_TOP_BOTTOM, Transpose.ROTATE_90, Transpose.ROTATE_180, Transpose.ROTATE_270, Transpose.TRANSPOSE or Transpose.TRANSVERSE.

Returns:

Returns a flipped or rotated copy of this image.

This flips the input image by using the Transpose.FLIP_LEFT_RIGHT method.

from PIL import Image

with Image.open("hopper.jpg") as im:

    # Flip the image from left to right
    im_flipped = im.transpose(method=Image.Transpose.FLIP_LEFT_RIGHT)
    # To flip the image from top to bottom,
    # use the method "Image.Transpose.FLIP_TOP_BOTTOM"
Image.verify()[source]

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.

Image.load()[source]

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.

If the file associated with the image was opened by Pillow, then this method will close it. The exception to this is if the image has multiple frames, in which case the file will be left open for seek operations. See File Handling in Pillow for more information.

Returns:

An image access object.

Return type:

PixelAccess Class or PIL.PyAccess

Image.close()[source]

Closes the file pointer, if possible.

This operation will destroy the image core and release its memory. The image data will be unusable afterward.

This function is required to close images that have multiple frames or have not had their file read and closed by the load() method. See File Handling in Pillow for more information.

Image Attributes

Instances of the Image class have the following attributes:

Image.filename: str

The filename or path of the source file. Only images created with the factory function open have a filename attribute. If the input is a file like object, the filename attribute is set to an empty string.

Image.format: Optional[str]

The file format of the source file. For images created by the library itself (via a factory function, or by running a method on an existing image), this attribute is set to None.

Image.mode: str

Image mode. This is a string specifying the pixel format used by the image. Typical values are “1”, “L”, “RGB”, or “CMYK.” See Modes for a full list.

Image.size: tuple[int]

Image size, in pixels. The size is given as a 2-tuple (width, height).

Image.width: int

Image width, in pixels.

Image.height: int

Image height, in pixels.

Image.palette: Optional[PIL.ImagePalette.ImagePalette]

Colour palette table, if any. If mode is “P” or “PA”, this should be an instance of the ImagePalette class. Otherwise, it should be set to None.

Image.info: dict

A dictionary holding data associated with the image. This dictionary is used by file handlers to pass on various non-image information read from the file. See documentation for the various file handlers for details.

Most methods ignore the dictionary when returning new images; since the keys are not standardized, it’s not possible for a method to know if the operation affects the dictionary. If you need the information later on, keep a reference to the info dictionary returned from the open method.

Unless noted elsewhere, this dictionary does not affect saving files.

Image.is_animated: bool

True if this image has more than one frame, or False otherwise.

This attribute is only defined by image plugins that support animated images. Plugins may leave this attribute undefined if they don’t support loading animated images, even if the given format supports animated images.

Given that this attribute is not present for all images use getattr(image, "is_animated", False) to check if Pillow is aware of multiple frames in an image regardless of its format.

See also

n_frames, seek() and tell()

Image.n_frames: int

The number of frames in this image.

This attribute is only defined by image plugins that support animated images. Plugins may leave this attribute undefined if they don’t support loading animated images, even if the given format supports animated images.

Given that this attribute is not present for all images use getattr(image, "n_frames", 1) to check the number of frames that Pillow is aware of in an image regardless of its format.

See also

is_animated, seek() and tell()

Classes

class PIL.Image.Exif[source]

Bases: MutableMapping

bigtiff = False
endian = None
get_ifd(tag)[source]
hide_offsets()[source]
load(data)[source]
load_from_fp(fp, offset=None)[source]
tobytes(offset=8)[source]
class PIL.Image.ImagePointHandler[source]

Used as a mixin by point transforms (for use with point())

class PIL.Image.ImageTransformHandler[source]

Used as a mixin by geometry transforms (for use with transform())

Constants

PIL.Image.NONE
PIL.Image.MAX_IMAGE_PIXELS

Set to 89,478,485, approximately 0.25GB for a 24-bit (3 bpp) image. See open() for more information about how this is used.

Transpose methods

Used to specify the Image.transpose() method to use.

class PIL.Image.Transpose(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]
FLIP_LEFT_RIGHT = 0
FLIP_TOP_BOTTOM = 1
ROTATE_180 = 3
ROTATE_270 = 4
ROTATE_90 = 2
TRANSPOSE = 5
TRANSVERSE = 6

Transform methods

Used to specify the Image.transform() method to use.

class PIL.Image.Transform[source]
AFFINE

Affine transform

EXTENT

Cut out a rectangular subregion

PERSPECTIVE

Perspective transform

QUAD

Map a quadrilateral to a rectangle

MESH

Map a number of source quadrilaterals in one operation

Resampling filters

See Filters for details.

class PIL.Image.Resampling(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]
BICUBIC = 3
BILINEAR = 2
BOX = 4
HAMMING = 5
LANCZOS = 1
NEAREST = 0

Some deprecated filters are also available under the following names:

PIL.Image.NONE = Resampling.NEAREST
PIL.Image.LINEAR = Resampling.BILINEAR
PIL.Image.CUBIC = Resampling.BICUBIC
PIL.Image.ANTIALIAS = Resampling.LANCZOS

Dither modes

Used to specify the dithering method to use for the convert() and quantize() methods.

class PIL.Image.Dither[source]
NONE

No dither

ORDERED

Not implemented

RASTERIZE

Not implemented

FLOYDSTEINBERG

Floyd-Steinberg dither

Palettes

Used to specify the pallete to use for the convert() method.

class PIL.Image.Palette(value, names=None, *, module=None, qualname=None, type=None, start=1, boundary=None)[source]
ADAPTIVE = 1
WEB = 0

Quantization methods

Used to specify the quantization method to use for the quantize() method.

class PIL.Image.Quantize[source]
MEDIANCUT

Median cut. Default method, except for RGBA images. This method does not support RGBA images.

MAXCOVERAGE

Maximum coverage. This method does not support RGBA images.

FASTOCTREE

Fast octree. Default method for RGBA images.

LIBIMAGEQUANT

libimagequant

Check support using PIL.features.check_feature() with feature="libimagequant".