jyapayne/glymur
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Added example for append method. Closes #103.

Browse source
This commit is contained in:
jevans 2013-08-18 19:58:45 -04:00
commit e74718655f
1 changed files with 44 additions and 6 deletions
Download patch file Download diff file Expand all files Collapse all files

50
docs/source/how_do_i.rst
View file

@ -3,7 +3,7 @@ How do I...?
------------
Read the lowest resolution thumbnail?
read the lowest resolution thumbnail?
=====================================
Printing the Jp2k object should reveal the number of resolutions (look in the
COD segment section), but you can take a shortcut by supplying -1 as the
@ -14,7 +14,7 @@ resolution level. ::
>>> j = glymur.Jp2k(file)
>>> thumbnail = j.read(rlevel=-1)
Display metadata?
display metadata?
=================
There are two ways. From the unix command line, the script *jp2dump* is
available. ::
@ -34,8 +34,41 @@ codestream box, only the main header is printed. It is possible to print
>>> print(j.get_codestream())
Add XML Metadata?
add XML metadata?
=================
You can append any number of XML boxes to a JP2 file (not to a raw codestream).
Consider the following XML file `data.xml` : ::
<?xml version="1.0"?>
<info>
<locality>
<city>Boston</city>
<snowfall>24.9 inches</snowfall>
</locality>
<locality>
<city>Portland</city>
<snowfall>31.9 inches</snowfall>
</locality>
<locality>
<city>New York City</city>
<snowfall>11.4 inches</snowfall>
</locality>
</info>
The **append** method can add an XML box (only XML boxes are currently
allowed)::
>>> import shutil
>>> import glymur
>>> shutil.copyfile(glymur.data.nemo(), 'myfile.jp2')
>>> from xml.etree import cElementTree as ET
>>> jp2 = glymur.Jp2k('myfile.jp2')
>>> xmlbox = glymur.jp2box.XMLBox(filename='data.xml')
>>> jp2.append(xmlbox)
>>> print(jp2)
add metadata in a more general fashion?
=======================================
An existing raw codestream (or JP2 file) can be wrapped (re-wrapped) in a
user-defined set of JP2 boxes. To get just a minimal JP2 jacket on the
codestream provided by `goodstuff.j2k` (a file consisting of a raw codestream),
@ -87,7 +120,7 @@ though. Take the following example content in an XML file `favorites.xml` : ::
and add it after the JP2 header box, but before the codestream box ::
>>> boxes = jp2.box # The box attribute is the list of JP2 boxes
>>> xmlbox = glymur.jp2box.XMLBox(file='favorites.xml')
>>> xmlbox = glymur.jp2box.XMLBox(filename='favorites.xml')
>>> boxes.insert(3, xmlbox)
>>> jp2_xml = jp2.wrap("newfile_with_xml.jp2", boxes=boxes)
>>> print(jp2_xml)
@ -119,7 +152,12 @@ and add it after the JP2 header box, but before the codestream box ::
. (truncated)
.
Create an image with an alpha layer?
As to the question of which method you should use, **append** or **wrap**,
to add metadata, you should keep in mind that **wrap** produces a new JP2 file,
while **append** modifies an existing file and is currently limited to XML
boxes.
create an image with an alpha layer?
====================================
OpenJPEG can create JP2 files with more than 3 components (requires
@ -181,7 +219,7 @@ Here's how the Preview application on the mac shows the RGBA image.
.. image:: goodstuff_alpha.png
Work with XMP UUIDs?
work with XMP UUIDs?
====================
The example JP2 file shipped with glymur has an XMP UUID. ::