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deprecated read method, removed write method, closes #299

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use array-style slicing instead.  Many former read methods are now
properties.  Many former write method parameters are now moved into the
constructor.
This commit is contained in:
John Evans 2014-11-11 10:46:59 -05:00
commit 03cb19d22b
16 changed files with 1132 additions and 1188 deletions
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27
docs/source/how_do_i.rst
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@ -14,27 +14,22 @@ retrieve a full resolution and first lower-resolution image ::
>>> jp2file = glymur.data.nemo() # just a path to a JPEG2000 file
>>> jp2 = glymur.Jp2k(jp2file)
>>> fullres = jp2[:]
>>> print(fullres.shape)
>>> fullres.shape
(1456, 2592, 3)
>>> thumbnail = jp2[::2, ::2]
>>> print(thumbnail.shape)
>>> thumbnail.shape
(728, 1296, 3)
The :py:meth:`read` method exposes many more options for other JPEG 2000
features such as quality layers.
... write images?
=================
So long as the image data can fit entirely into memory, array-style slicing may
also be used to write JPEG 2000 files.
It's pretty simple, just supply the image data as the 2nd argument to the Jp2k
constructor.
>>> import glymur, numpy as np
>>> jp2 = glymur.Jp2k('zeros.jp2', mode='wb')
>>> jp2[:] = np.zeros((640, 480), dtype=np.uint8)
>>> data = np.zeros((640, 480), dtype=np.uint8)
>>> jp2 = glymur.Jp2k('zeros.jp2', data=data)
The :py:meth:`write` method exposes many more options for other JPEG 2000
features. You should have OpenJPEG version 1.5 or more recent before writing
JPEG 2000 images.
You should have OpenJPEG version 1.5 or more recent before writing JPEG 2000 images.
... display metadata?
=====================
@ -354,15 +349,14 @@ image isn't square. ::
>>> import numpy as np
>>> import glymur
>>> from glymur import Jp2k
>>> rgb = Jp2k(glymur.data.goodstuff()).read()
>>> rgb = Jp2k(glymur.data.goodstuff())[:]
>>> lx, ly = rgb.shape[0:2]
>>> X, Y = np.ogrid[0:lx, 0:ly]
>>> mask = ly**2*(X - lx / 2) ** 2 + lx**2*(Y - ly / 2) ** 2 > (lx * ly / 2)**2
>>> alpha = 255 * np.ones((lx, ly, 1), dtype=np.uint8)
>>> alpha[mask] = 0
>>> rgba = np.concatenate((rgb, alpha), axis=2)
>>> jp2 = Jp2k('tmp.jp2', 'wb')
>>> jp2[:] = rgba
>>> jp2 = Jp2k('tmp.jp2', data=rgba)
Next we need to specify what types of channels we have.
The first three channels are color channels, but we identify the fourth as
@ -465,8 +459,7 @@ http://photojournal.jpl.nasa.gov/tiff/PIA17145.tif info JPEG 2000::
>>> import skimage.io
>>> image = skimage.io.imread('PIA17145.tif')
>>> from glymur import Jp2k
>>> jp2 = Jp2k('PIA17145.jp2', 'wb')
>>> jp2[:] = image
>>> jp2 = Jp2k('PIA17145.jp2', data=image)
Next you can extract the XMP metadata.