Opens and manipulates images. Image objects can be used in with statement, and these resources will be automatically managed (even if any error happened):
with Image(filename='pikachu.png') as i:
print 'width =', i.width
print 'height =', i.height
(tuple) The list of alpha channel types
See also
ImageMagick Image Channel Describes the SetImageAlphaChannel method which can be used to modify alpha channel. Also describes AlphaChannelType
(dict) The dictionary of channel types.
See also
(tuple) The list of composition operators
See also
(tuple) The list of evaluation operators
See also
(tuple) The list of filter types.
See also
(tuple) The list of image types
See also
(tuple) The list of resolution unit types
See also
An error that rises when some code tries access to an already closed image.
An image object.
Parameters: |
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New in version 0.1.5: The file parameter.
New in version 0.1.1: The blob parameter.
New in version 0.2.1: The format parameter.
New in version 0.2.2: The width, height, background parameters.
Crops the image by its left, right, top and bottom, and then returns the cropped one.
with img[100:200, 150:300] as cropped:
# manipulated the cropped image
pass
Like other subscriptable objects, default is 0 or its width/height:
img[:, :] #--> just clone
img[:100, 200:] #--> equivalent to img[0:100, 200:img.height]
Negative integers count from the end (width/height):
img[-70:-50, -20:-10]
#--> equivalent to img[width-70:width-50, height-20:height-10]
Returns : | the cropped image |
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Rtype : | Image |
New in version 0.1.2.
(bool) Get state of image alpha channel. It can also be used to enable/disable alpha channel.
New in version 0.2.1.
(wand.color.Color) The image background color. It can also be set to change the background color.
New in version 0.1.9.
Clones the image. It is equivalent to call Image with image parameter.
with img.clone() as cloned:
# manipulate the cloned image
pass
Returns: | the cloned new image |
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Return type: | Image |
New in version 0.1.1.
Closes the image explicitly. If you use the image object in with statement, it was called implicitly so don’t have to call it.
Note
It has the same functionality of destroy() method.
Places the supplied image over the current image, with the top left corner of image at coordinates left, top of the current image. The dimensions of the current image are not changed.
Parameters: |
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New in version 0.2.0.
(numbers.Integral) Compression quality of this image.
New in version 0.2.0.
Converts the image format with the original image maintained. It returns a converted image instance which is new.
with img.convert('png') as converted:
converted.save(filename='converted.png')
Parameters: | format (basestring) – image format to convert to |
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Returns: | a converted image |
Return type: | Image |
Raises : | ValueError when the given format is unsupported |
New in version 0.1.6.
Crops the image in-place.
+--------------------------------------------------+
| ^ ^ |
| | | |
| top | |
| | | |
| v | |
| <-- left --> +-------------------+ bottom |
| | ^ | | |
| | <-- width --|---> | | |
| | height | | |
| | | | | |
| | v | | |
| +-------------------+ v |
| <--------------- right ----------> |
+--------------------------------------------------+
Parameters: |
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Raises exceptions.ValueError: | |
when one or more arguments are invalid |
Note
If you want to crop the image but not in-place, use slicing operator.
Changed in version 0.1.8: Made to raise ValueError instead of IndexError for invalid width/height arguments.
New in version 0.1.7.
(numbers.Integral) The depth of this image.
New in version 0.2.1.
(basestring) The image format.
If you want to convert the image format, just reset this property:
assert isinstance(img, wand.image.Image)
img.format = 'png'
It may raise ValueError when the format is unsupported.
See also
New in version 0.1.6.
(numbers.Integral) The height of this image.
Makes the binary string of the image.
Parameters: | format (basestring) – the image format to write e.g. 'png', 'jpeg'. it is omittable |
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Returns: | a blob (bytes) string |
Return type: | str |
Raises : | ValueError when format is invalid |
Changed in version 0.1.6: Removed a side effect that changes the image format silently.
New in version 0.1.5: The format parameter became optional.
New in version 0.1.1.
(basestring) The MIME type of the image e.g. 'image/jpeg', 'image/png'.
New in version 0.1.7.
(int) The maxumim value of a color channel that is supported by the imagemgick library.
New in version 0.2.0.
Reset the coordinate frame of the image so to the upper-left corner is (0, 0) again (crop and rotate operations change it).
New in version 0.2.0.
Resizes the image.
Parameters: |
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Changed in version 0.2.1: The default value of filter has changed from 'triangle' to 'undefined' instead.
Changed in version 0.1.8: The blur parameter changed to take numbers.Real instead of numbers.Rational.
New in version 0.1.1.
Rotates the image right. It takes a background color for degree that isn’t a multiple of 90.
Parameters: |
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New in version 0.2.0: The reset_coords parameter.
New in version 0.1.8.
Saves the image into the file or filename. It takes only one argument at a time.
Parameters: |
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New in version 0.1.5: The file parameter.
New in version 0.1.1.
(str) The SHA-256 message digest for the image pixel stream.
New in version 0.1.9.
Strips an image of all profiles and comments.
New in version 0.2.0.
Transforms the image using MagickTransformImage(), which is a convenience function accepting geometry strings to perform cropping and resizing. Cropping is performed first, followed by resizing. Either or both arguments may be omitted or given an empty string, in which case the corresponding action will not be performed. Geometry specification strings are defined as follows:
A geometry string consists of a size followed by an optional offset. The size is specified by one of the options below, where bold terms are replaced with appropriate integer values:
The offset, which only applies to the cropping geometry string, is given by {+-}x{+-}y, that is, one plus or minus sign followed by an x offset, followed by another plus or minus sign, followed by a y offset. Offsets are in pixels from the upper left corner of the image. Negative offsets will cause the corresponding number of pixels to be removed from the right or bottom edge of the image, meaning the cropped size will be the computed size minus the absolute value of the offset.
For example, if you want to crop your image to 300x300 pixels and then scale it by 2x for a final size of 600x600 pixels, you can call:
image.transform('300x300', '200%')
This method is a fairly thing wrapper for the C API, and does not perform any additional checking of the parameters except insofar as verifying that they are of the correct type. Thus, like the C API function, the method is very permissive in terms of what it accepts for geometry strings; unrecognized strings and trailing characters will be ignored rather than raising an error.
Parameters: |
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Note
#104 reported that transform() leaks memory under version 0.3.0, so be careful when you use it on long-running process like web server.
See also
New in version 0.2.2.
Makes the image transparent by subtracting some percentage of the black color channel. The transparency parameter specifies the percentage.
Parameters: | transparency (numbers.Real) – the percentage fade that should be performed on the image, from 0.0 to 1.0 |
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New in version 0.2.0.
Remove solid border from image. Uses top left pixel as a guide.
New in version 0.2.1.
(basestring) The image type.
Defines image type as in wand.image.IMAGE_TYPES enumeration.
It may raise ValueError when the type is unknown.
New in version 0.2.2.
(basestring) The resolution units of this image.
Internal pointer to the MagickWand instance. It may raise ClosedImageError when the instance has destroyed already.
Transparentized the supplied image and places it over the current image, with the top left corner of image at coordinates left, top of the current image. The dimensions of the current image are not changed.
Parameters: |
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New in version 0.2.0.
(numbers.Integral) The width of this image.
Row iterator for Image. It shouldn’t be instantiated directly; instead, it can be acquired through Image instance:
assert isinstance(image, wand.image.Image)
iterator = iter(image)
It doesn’t iterate every pixel, but rows. For example:
for row in image:
for col in row:
assert isinstance(col, wand.color.Color)
print col
Every row is a collections.Sequence which consists of one or more wand.color.Color values.
Parameters: | image (Image) – the image to get an iterator |
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New in version 0.1.3.
Clones the same iterator.