Fix comment for interleave_planes
@@ -226,15 +226,23 @@ def tostring(row):
def interleave_planes(ipixels, apixels, ipsize, apsize):
"""
- Interleave (colour) planes, e.g. RGB + A = RGBA.
-
- Return an array of pixels consisting of the `ipsize` elements of
- data from each pixel in `ipixels` followed by the `apsize` elements
- of data from each pixel in `apixels`. Conventionally `ipixels`
- and `apixels` are byte arrays so the sizes are bytes, but it
- actually works with any arrays of the same type. The returned
- array is the same type as the input arrays which should be the
- same type as each other.
+ Interleave planes.
+ Typically used to interleave intensity planes (RGB) with
+ alpha planes (A): RGB + A = RGBA.
+
+ Return an array where each pixel of the output constists of
+ `ipsize` elements from `ipixels` immediately followed by
+ `apsize` elements from `apixels`.
+
+ Typically (when performing RGB + A on 8-bit inputs)
+ `ipsize` = 3, and `apsize` = 1.
+
+ Conventionally `ipixels` and `apixels` are byte arrays
+ so the sizes are bytes, but
+ it actually works with any arrays of the same type.
+
+ The returned array is the same type as the input arrays
+ which should be the same type as each other.
"""
itotal = len(ipixels)
