note on use of new_from_memory_copy

for py docs

see https://github.com/jcupitt/libvips/issues/346#issuecomment-248536958
This commit is contained in:
John Cupitt 2016-09-21 10:50:53 +01:00
parent eb91dda83c
commit 5b31408fd3

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@ -491,7 +491,8 @@ result_image = image1.bandjoin([image2, 255])
<refsect3 id="python-memory">
<title>Reading and writing areas of memory</title>
<para>
You can use the C API functions vips_image_new_from_memory() and
You can use the C API functions vips_image_new_from_memory(),
vips_image_new_from_memory_copy() and
vips_image_write_to_memory() directly from Python to read and write
areas of memory. This can be useful if you need to get images to and
from other other image processing libraries, like PIL or numpy.
@ -540,8 +541,11 @@ image2 = Vips.Image.new_from_memory(memory_area,
collector and
you later try to use <code>image2</code>, you'll get a crash.
Make sure you keep a reference to <code>memory_area</code> around
for as long as you need it.
for as long as you need it. A simple solution is to use
<code>new_from_memory_copy</code> instead. This will take a copy of the
memory area for vips. Of course this will raise memory usage.
</para>
</refsect3>
<refsect3 id="python-modify">