ImageDraw
Module¶
The ImageDraw
module provide simple 2D graphics for
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.
Example: Draw a gray cross over an image¶
from PIL import Image, ImageDraw
im = Image.open("lena.pgm")
draw = ImageDraw.Draw(im)
draw.line((0, 0) + im.size, fill=128)
draw.line((0, im.size[1], im.size[0], 0), fill=128)
del draw
# 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
PIL.Image.Image.new()
or 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 don’t draw with more than 256 colors.
Color Names¶
See Color Names for the color names supported by Pillow.
Fonts¶
PIL can use bitmap fonts or OpenType/TrueType fonts.
Bitmap fonts are stored in PIL’s own format, where each font typically consists of a 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 ImageFont
module.
To load a OpenType/TrueType font, use the truetype function in the
ImageFont
module. Note that this function depends on third-party
libraries, and may not available in all PIL builds.
Example: Draw Partial Opacity Text¶
from PIL import Image, ImageDraw, ImageFont
# get an image
base = Image.open('Pillow/Tests/images/lena.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¶
-
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.
参数: - im – The image to draw in.
- 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¶
-
PIL.ImageDraw.Draw.
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.
参数: - xy – Four points to define the bounding box. Sequence of
[(x0, y0), (x1, y1)]
or[x0, y0, x1, y1]
. - start – Starting angle, in degrees. Angles are measured from 3 o’clock, increasing clockwise.
- end – Ending angle, in degrees.
- fill – Color to use for the arc.
- xy – Four points to define the bounding box. Sequence of
-
PIL.ImageDraw.Draw.
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
paste()
method on the image itself.
-
PIL.ImageDraw.Draw.
chord
(xy, start, end, fill=None, outline=None)¶ Same as
arc()
, but connects the end points with a straight line.参数: - xy – Four points to define the bounding box. Sequence of
[(x0, y0), (x1, y1)]
or[x0, y0, x1, y1]
. - outline – Color to use for the outline.
- fill – Color to use for the fill.
- xy – Four points to define the bounding box. Sequence of
-
PIL.ImageDraw.Draw.
ellipse
(xy, fill=None, outline=None)¶ Draws an ellipse inside the given bounding box.
参数: - xy – Four points to define the bounding box. Sequence of either
[(x0, y0), (x1, y1)]
or[x0, y0, x1, y1]
. - outline – Color to use for the outline.
- fill – Color to use for the fill.
- xy – Four points to define the bounding box. Sequence of either
-
PIL.ImageDraw.Draw.
line
(xy, fill=None, width=0)¶ Draws a line between the coordinates in the xy list.
参数: - xy – Sequence of either 2-tuples like
[(x, y), (x, y), ...]
or numeric values like[x, y, x, y, ...]
. - fill – Color to use for the line.
- width –
The line width, in pixels. Note that line joins are not handled well, so wide polylines will not look good.
1.1.5 新版功能.
注解
This option was broken until version 1.1.6.
- xy – Sequence of either 2-tuples like
-
PIL.ImageDraw.Draw.
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.
参数: - xy – Four points to define the bounding box. Sequence of
[(x0, y0), (x1, y1)]
or[x0, y0, x1, y1]
. - start – Starting angle, in degrees. Angles are measured from 3 o’clock, increasing clockwise.
- end – Ending angle, in degrees.
- fill – Color to use for the fill.
- outline – Color to use for the outline.
- xy – Four points to define the bounding box. Sequence of
-
PIL.ImageDraw.Draw.
point
(xy, fill=None)¶ Draws points (individual pixels) at the given coordinates.
参数: - xy – Sequence of either 2-tuples like
[(x, y), (x, y), ...]
or numeric values like[x, y, x, y, ...]
. - fill – Color to use for the point.
- xy – Sequence of either 2-tuples like
-
PIL.ImageDraw.Draw.
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.
参数: - xy – Sequence of either 2-tuples like
[(x, y), (x, y), ...]
or numeric values like[x, y, x, y, ...]
. - outline – Color to use for the outline.
- fill – Color to use for the fill.
- xy – Sequence of either 2-tuples like
-
PIL.ImageDraw.Draw.
rectangle
(xy, fill=None, outline=None)¶ Draws a rectangle.
参数: - xy – Four 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. - outline – Color to use for the outline.
- fill – Color to use for the fill.
- xy – Four points to define the bounding box. Sequence of either
-
PIL.ImageDraw.Draw.
shape
(shape, fill=None, outline=None)¶ 警告
This method is experimental.
Draw a shape.
-
PIL.ImageDraw.Draw.
text
(xy, text, fill=None, font=None, anchor=None, spacing=0, align="left")¶ Draws the string at the given position.
参数: - xy – Top left corner of the text.
- text – Text to be drawn. If it contains any newline characters, the text is passed on to multiline_text()
- fill – Color to use for the text.
- font – An
ImageFont
instance. - spacing – If the text is passed on to multiline_text(), the number of pixels between lines.
- align – If the text is passed on to multiline_text(), “left”, “center” or “right”.
-
PIL.ImageDraw.Draw.
multiline_text
(xy, text, fill=None, font=None, anchor=None, spacing=0, align="left")¶ Draws the string at the given position.
参数: - xy – Top left corner of the text.
- text – Text to be drawn.
- fill – Color to use for the text.
- font – An
ImageFont
instance. - spacing – The number of pixels between lines.
- align – “left”, “center” or “right”.
-
PIL.ImageDraw.Draw.
textsize
(text, font=None, spacing=0)¶ Return the size of the given string, in pixels.
参数: - text – Text to be measured. If it contains any newline characters, the text is passed on to multiline_textsize()
- font – An
ImageFont
instance. - spacing – If the text is passed on to multiline_textsize(), the number of pixels between lines.
-
PIL.ImageDraw.Draw.
multiline_textsize
(text, font=None, spacing=0)¶ Return the size of the given string, in pixels.
参数: - text – Text to be measured.
- font – An
ImageFont
instance. - spacing – The number of pixels between lines.
Legacy API¶
The Draw
class contains a constructor and a number
of methods which are provided for backwards compatibility only. For this to
work properly, you should either use options on the drawing primitives, or
these methods. Do not mix the old and new calling conventions.
-
PIL.ImageDraw.Draw.
setfont
(font)¶ 1.1.5 版后已移除.
Sets the default font to use for the text method.
参数: font – An ImageFont
instance.