1.0.1

Bug-fix release.  This fixes a bug found by Dave Fisher.  For
high-amplitude input, strange lines would appear across the display.
This was caused by an element of one of the FFT buffers not being
initialised properly.  The fix also cleans up some of the rubbish that
used to appear around the Nyquist frequency.

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1.0.0

First 'stable' release, although it has been stable for ages.

It is now possible to 'follow' a file whilst it is being written.
Pressing '.' causes BWView to recheck the file to see if any further
data has been written.  In this way you can analyse a session at the
same time that it is being recorded by another program, paging
backwards and forwards, and so on, independently of the recording
process.

If started with the -x option, two additional types of window are now
available.  These are based on IIR low-pass filters.  These do not
give much benefit for analysis, but rather they are here to test the
filters and compare them against the Blackman window.  The advantage
of the IIR filters is that they run very fast and can be used in
real-time, as a filterbank.  The disadvantages can be the asymmetry of
the window, and its long tail.

With -x, then the 'x' setting appears.  'x1' is the default Blackman
window.  'x2' gives IIR with Q=0.5, and 'x3' gives IIR with Q=0.72.
The significance of Q=0.5 is that this is the largest Q for which the
tail doesn't cross 0, and Q=0.72 gives the squarest frequency response
without a dip in the middle at the top.

Clicking on a point shows the window used to calculate that point just
as before, so you can see the shape of the windows produced by the IIR
filters.

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0.1.1 New features to try:

New modes: m2, m3, m4, m5, m6, m7, m8.  Currently defaults to m4

m4: The same as m1 (i.e. a pure magnitude display), except rendered
using colours to map different levels of intensity.  This works
better, because you get some visual comparison between levels of
similar magnitude.

m3, m5: As m4, except the magnitude controls the 'elevation', giving
something like a sideways waterfall display.  m3 gives a view from the
right, m5 from the left.  This displays exactly the same detail as m4,
so the shapes are completely smooth.

m2, m6: As m3+m5, except that elevations are only drawn every 8
pixels, showing the maximum value within that range.  This gives a
contoured effect that makes it much easier to see the shape of
'low-lying hills'.  However, a lot of detail is lost.

m7: Adds hues to the m1 display, using hue to indicate how much the
phase is shifting at that point.  If the phase is changing, this
indicates that we're close but not actually on the centre-frequency of
the signal.  The cyan areas are closest, and then it goes in the order
green..red..blue.  By watching the cyan areas, you should be able to
track the centre of the tone.

m8: Uses the phase shift information to instead reduce the displayed
level of non-in-phase areas.  This has the effect of sharpening up the
display.  However, it also makes it more sensitive to fluctuations.

[ I'm not sure about the usefulness of m7 and m8.  I might drop these
two displays, unless someone finds them useful in some way. ]

New -W option to allow setting the initial window size from the
command-line.

Font automatically adjusts according to window width.  

Signal display: s1 now gives full-scale for -1 to +1 signals (which is
full-scale for all integer data types).

Magnitude levels: reading the magnitude using the cursor appears to
give reasonably accurate values (3sf at least).  The magnitude
read-out gives the correct amplitude level for pure sine waves.  (So a
full-scale integer sine-wave test tone gives a reading of 1.0).

