Pillow/docs/reference/ImageDraw.rst
2018-07-02 11:21:30 +03:00

389 lines
15 KiB
ReStructuredText
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

.. py:module:: PIL.ImageDraw
.. py:currentmodule:: PIL.ImageDraw
:py:mod:`ImageDraw` Module
==========================
The :py:mod:`ImageDraw` module provides simple 2D graphics for
:py:class:`~PIL.Image.Image` objects. You can use this module to create new
images, annotate or retouch existing images, and to generate graphics on the
fly for web use.
For a more advanced drawing library for PIL, see the `aggdraw module`_.
.. _aggdraw module: https://github.com/pytroll/aggdraw
Example: Draw a gray cross over an image
----------------------------------------
.. code-block:: python
from PIL import Image, ImageDraw
im = Image.open("hopper.jpg")
draw = ImageDraw.Draw(im)
draw.line((0, 0) + im.size, fill=128)
draw.line((0, im.size[1], im.size[0], 0), fill=128)
# write to stdout
im.save(sys.stdout, "PNG")
Concepts
--------
Coordinates
^^^^^^^^^^^
The graphics interface uses the same coordinate system as PIL itself, with (0,
0) in the upper left corner.
Colors
^^^^^^
To specify colors, you can use numbers or tuples just as you would use with
:py:meth:`PIL.Image.new` or :py:meth:`PIL.Image.Image.putpixel`. For “1”,
“L”, and “I” images, use integers. For “RGB” images, use a 3-tuple containing
integer values. For “F” images, use integer or floating point values.
For palette images (mode “P”), use integers as color indexes. In 1.1.4 and
later, you can also use RGB 3-tuples or color names (see below). The drawing
layer will automatically assign color indexes, as long as you dont draw with
more than 256 colors.
Color Names
^^^^^^^^^^^
See :ref:`color-names` for the color names supported by Pillow.
Fonts
^^^^^
PIL can use bitmap fonts or OpenType/TrueType fonts.
Bitmap fonts are stored in PILs own format, where each font typically consists
of two files, one named .pil and the other usually named .pbm. The former
contains font metrics, the latter raster data.
To load a bitmap font, use the load functions in the :py:mod:`~PIL.ImageFont`
module.
To load a OpenType/TrueType font, use the truetype function in the
:py:mod:`~PIL.ImageFont` module. Note that this function depends on third-party
libraries, and may not available in all PIL builds.
Example: Draw Partial Opacity Text
----------------------------------
.. code-block:: python
from PIL import Image, ImageDraw, ImageFont
# get an image
base = Image.open('Pillow/Tests/images/hopper.png').convert('RGBA')
# make a blank image for the text, initialized to transparent text color
txt = Image.new('RGBA', base.size, (255,255,255,0))
# get a font
fnt = ImageFont.truetype('Pillow/Tests/fonts/FreeMono.ttf', 40)
# get a drawing context
d = ImageDraw.Draw(txt)
# draw text, half opacity
d.text((10,10), "Hello", font=fnt, fill=(255,255,255,128))
# draw text, full opacity
d.text((10,60), "World", font=fnt, fill=(255,255,255,255))
out = Image.alpha_composite(base, txt)
out.show()
Functions
---------
.. py:class:: PIL.ImageDraw.Draw(im, mode=None)
Creates an object that can be used to draw in the given image.
Note that the image will be modified in place.
:param im: The image to draw in.
:param mode: Optional mode to use for color values. For RGB
images, this argument can be RGB or RGBA (to blend the
drawing into the image). For all other modes, this argument
must be the same as the image mode. If omitted, the mode
defaults to the mode of the image.
Methods
-------
.. py:method:: PIL.ImageDraw.ImageDraw.getfont()
Get the current default font.
:returns: An image font.
.. py:method:: PIL.ImageDraw.ImageDraw.arc(xy, start, end, fill=None)
Draws an arc (a portion of a circle outline) between the start and end
angles, inside the given bounding box.
:param xy: Two points to define the bounding box. Sequence of
``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``,
where ``x1 >= x0`` and ``y1 >= y0``.
:param start: Starting angle, in degrees. Angles are measured from
3 o'clock, increasing clockwise.
:param end: Ending angle, in degrees.
:param fill: Color to use for the arc.
.. py:method:: PIL.ImageDraw.ImageDraw.bitmap(xy, bitmap, fill=None)
Draws a bitmap (mask) at the given position, using the current fill color
for the non-zero portions. The bitmap should be a valid transparency mask
(mode “1”) or matte (mode “L” or “RGBA”).
This is equivalent to doing ``image.paste(xy, color, bitmap)``.
To paste pixel data into an image, use the
:py:meth:`~PIL.Image.Image.paste` method on the image itself.
.. py:method:: PIL.ImageDraw.ImageDraw.chord(xy, start, end, fill=None, outline=None)
Same as :py:meth:`~PIL.ImageDraw.ImageDraw.arc`, but connects the end points
with a straight line.
:param xy: Two points to define the bounding box. Sequence of
``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``,
where ``x1 >= x0`` and ``y1 >= y0``.
:param outline: Color to use for the outline.
:param fill: Color to use for the fill.
.. py:method:: PIL.ImageDraw.ImageDraw.ellipse(xy, fill=None, outline=None)
Draws an ellipse inside the given bounding box.
:param xy: Two points to define the bounding box. Sequence of either
``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``,
where ``x1 >= x0`` and ``y1 >= y0``.
:param outline: Color to use for the outline.
:param fill: Color to use for the fill.
.. py:method:: PIL.ImageDraw.ImageDraw.line(xy, fill=None, width=0)
Draws a line between the coordinates in the **xy** list.
:param xy: Sequence of either 2-tuples like ``[(x, y), (x, y), ...]`` or
numeric values like ``[x, y, x, y, ...]``.
:param fill: Color to use for the line.
:param width: The line width, in pixels. Note that line
joins are not handled well, so wide polylines will not look good.
.. versionadded:: 1.1.5
.. note:: This option was broken until version 1.1.6.
.. py:method:: PIL.ImageDraw.ImageDraw.pieslice(xy, start, end, fill=None, outline=None)
Same as arc, but also draws straight lines between the end points and the
center of the bounding box.
:param xy: Two points to define the bounding box. Sequence of
``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``,
where ``x1 >= x0`` and ``y1 >= y0``.
:param start: Starting angle, in degrees. Angles are measured from
3 o'clock, increasing clockwise.
:param end: Ending angle, in degrees.
:param fill: Color to use for the fill.
:param outline: Color to use for the outline.
.. py:method:: PIL.ImageDraw.ImageDraw.point(xy, fill=None)
Draws points (individual pixels) at the given coordinates.
:param xy: Sequence of either 2-tuples like ``[(x, y), (x, y), ...]`` or
numeric values like ``[x, y, x, y, ...]``.
:param fill: Color to use for the point.
.. py:method:: PIL.ImageDraw.ImageDraw.polygon(xy, fill=None, outline=None)
Draws a polygon.
The polygon outline consists of straight lines between the given
coordinates, plus a straight line between the last and the first
coordinate.
:param xy: Sequence of either 2-tuples like ``[(x, y), (x, y), ...]`` or
numeric values like ``[x, y, x, y, ...]``.
:param outline: Color to use for the outline.
:param fill: Color to use for the fill.
.. py:method:: PIL.ImageDraw.ImageDraw.rectangle(xy, fill=None, outline=None, width=0)
Draws a rectangle.
:param xy: Two points to define the bounding box. Sequence of either
``[(x0, y0), (x1, y1)]`` or ``[x0, y0, x1, y1]``. The second point
is just outside the drawn rectangle.
:param outline: Color to use for the outline.
:param fill: Color to use for the fill.
:param width: The line width, in pixels.
.. versionadded:: 5.2.0
.. py:method:: PIL.ImageDraw.ImageDraw.shape(shape, fill=None, outline=None)
.. warning:: This method is experimental.
Draw a shape.
.. py:method:: PIL.ImageDraw.ImageDraw.text(xy, text, fill=None, font=None, anchor=None, spacing=0, align="left", direction=None, features=None)
Draws the string at the given position.
:param xy: Top left corner of the text.
:param text: Text to be drawn. If it contains any newline characters,
the text is passed on to multiline_text()
:param fill: Color to use for the text.
:param font: An :py:class:`~PIL.ImageFont.ImageFont` instance.
:param spacing: If the text is passed on to multiline_text(),
the number of pixels between lines.
:param align: If the text is passed on to multiline_text(),
"left", "center" or "right".
:param direction: Direction of the text. It can be 'rtl' (right to
left), 'ltr' (left to right), 'ttb' (top to
bottom) or 'btt' (bottom to top). Requires
libraqm.
.. versionadded:: 4.2.0
:param features: A list of OpenType font features to be used during text
layout. This is usually used to turn on optional
font features that are not enabled by default,
for example 'dlig' or 'ss01', but can be also
used to turn off default font features for
example '-liga' to disable ligatures or '-kern'
to disable kerning. To get all supported
features, see
https://docs.microsoft.com/en-us/typography/opentype/spec/featurelist
Requires libraqm.
.. versionadded:: 4.2.0
.. py:method:: PIL.ImageDraw.ImageDraw.multiline_text(xy, text, fill=None, font=None, anchor=None, spacing=0, align="left", direction=None, features=None)
Draws the string at the given position.
:param xy: Top left corner of the text.
:param text: Text to be drawn.
:param fill: Color to use for the text.
:param font: An :py:class:`~PIL.ImageFont.ImageFont` instance.
:param spacing: The number of pixels between lines.
:param align: "left", "center" or "right".
:param direction: Direction of the text. It can be 'rtl' (right to
left), 'ltr' (left to right), 'ttb' (top to
bottom) or 'btt' (bottom to top). Requires
libraqm.
.. versionadded:: 4.2.0
:param features: A list of OpenType font features to be used during text
layout. This is usually used to turn on optional
font features that are not enabled by default,
for example 'dlig' or 'ss01', but can be also
used to turn off default font features for
example '-liga' to disable ligatures or '-kern'
to disable kerning. To get all supported
features, see
https://docs.microsoft.com/en-us/typography/opentype/spec/featurelist
Requires libraqm.
.. versionadded:: 4.2.0
.. py:method:: PIL.ImageDraw.ImageDraw.textsize(text, font=None, spacing=4, direction=None, features=None)
Return the size of the given string, in pixels.
:param text: Text to be measured. If it contains any newline characters,
the text is passed on to multiline_textsize()
:param font: An :py:class:`~PIL.ImageFont.ImageFont` instance.
:param spacing: If the text is passed on to multiline_textsize(),
the number of pixels between lines.
:param direction: Direction of the text. It can be 'rtl' (right to
left), 'ltr' (left to right), 'ttb' (top to
bottom) or 'btt' (bottom to top). Requires
libraqm.
.. versionadded:: 4.2.0
:param features: A list of OpenType font features to be used during text
layout. This is usually used to turn on optional
font features that are not enabled by default,
for example 'dlig' or 'ss01', but can be also
used to turn off default font features for
example '-liga' to disable ligatures or '-kern'
to disable kerning. To get all supported
features, see
https://docs.microsoft.com/en-us/typography/opentype/spec/featurelist
Requires libraqm.
.. versionadded:: 4.2.0
.. py:method:: PIL.ImageDraw.ImageDraw.multiline_textsize(text, font=None, spacing=4, direction=None, features=None)
Return the size of the given string, in pixels.
:param text: Text to be measured.
:param font: An :py:class:`~PIL.ImageFont.ImageFont` instance.
:param spacing: The number of pixels between lines.
:param direction: Direction of the text. It can be 'rtl' (right to
left), 'ltr' (left to right), 'ttb' (top to
bottom) or 'btt' (bottom to top). Requires
libraqm.
.. versionadded:: 4.2.0
:param features: A list of OpenType font features to be used during text
layout. This is usually used to turn on optional
font features that are not enabled by default,
for example 'dlig' or 'ss01', but can be also
used to turn off default font features for
example '-liga' to disable ligatures or '-kern'
to disable kerning. To get all supported
features, see
https://docs.microsoft.com/en-us/typography/opentype/spec/featurelist
Requires libraqm.
.. versionadded:: 4.2.0
.. py:method:: PIL.ImageDraw.getdraw(im=None, hints=None)
.. warning:: This method is experimental.
A more advanced 2D drawing interface for PIL images,
based on the WCK interface.
:param im: The image to draw in.
:param hints: An optional list of hints.
:returns: A (drawing context, drawing resource factory) tuple.
.. py:method:: PIL.ImageDraw.floodfill(image, xy, value, border=None, thresh=0)
.. warning:: This method is experimental.
Fills a bounded region with a given color.
:param image: Target image.
:param xy: Seed position (a 2-item coordinate tuple).
:param value: Fill color.
:param border: Optional border value. If given, the region consists of
pixels with a color different from the border color. If not given,
the region consists of pixels having the same color as the seed
pixel.
:param thresh: Optional threshold value which specifies a maximum
tolerable difference of a pixel value from the 'background' in
order for it to be replaced. Useful for filling regions of non-
homogeneous, but similar, colors.