<![CDATA[
<html><head>
<title>Overview</title>
<meta name="generator" content="HelpMaker">
<meta name="keywords" content="">
<link rel="stylesheet" type="text/css" href="hm.css"></head>
<body bgcolor="#FFFCEA">
<table width="100%" border="0" cellspacing="0" cellpadding="2" bgcolor="#C0C0C0">
<tr>
<td align="left">
<body><div align="left"><font face="Arial" size="4"><span style=" font-size:16pt">Overview</span></font></div></body></html>
</td>
<td align="right">
<font face="Arial" size="2">
<a href="keyevents.htm">Next</a>
</font>
</td>
</tr></table>
<hr><body><p style="margin-left:0mm; margin-right:0mm; text-indent:0mm; margin-top:0.00mm; margin-bottom:0.00mm;"><font face="Times New Roman"><span style=" font-size:12pt">The ImageEdit library provides photographic image manipulation functions for
Basic4PPC applications. This library will run on both the desktop and  the device but
requires .NET 2.0 or later</span></font><p style="margin-left:0mm; margin-right:0mm; text-indent:0mm; margin-top:1.76mm; margin-bottom:1.76mm;"><font face="Times New Roman"><span style=" font-size:12pt">Within the Image Edit library you will find the ImageEdit object.</span></font><p style="margin-left:0mm; margin-right:0mm; text-indent:0mm; margin-top:1.76mm; margin-bottom:1.76mm;"><font face="Times New Roman"><span style=" font-size:12pt">The library accepts 24 (3 x 8) bit colour  bitmaps and saves them internally as
linearised 3 x 15 bit values using a default gamma of 2.2. A different input gamma
may be specified before loading a bitmap if required. Linearising is needed to avoid
colour shifts during processing and the additional resolution helps avoid information
loss and consequent colour banding and blocking that might occur if 8 bit values were
used.</span></font><div align="left"><font face="Times New Roman"><span style=" font-size:12pt">Various image processing functions may be applied to this internal version of the
image which may then be returned as a gamma corrected 24 bit image. The default
output gamma is 2.2 but other values may be specified. The image may also be saved
to a file in various formats.</span></font></div><div align="left"><font face="Times New Roman"><span style=" font-size:12pt"><br></span></font></div><div align="left"><font face="Times New Roman"><span style=" font-size:12pt">Instead of using built-in functions such as Soften or Sharpen the libary accepts 3 x 3
convolution filter parameters enabling the various processing functions to be specified
by the implementer. Google is your friend to find out more, start with a search on "3 x
3 image filter matrix".</span></font></div><div align="left"><font face="Times New Roman"><span style=" font-size:12pt"><br></span></font></div><div align="left"><font face="Times New Roman"><span style=" font-size:12pt">Input and ouput gamma aside most of the image manipulations operations are linear
functions. However non-linear operations can be a approximated by the Curve
method. This takes an Array(256) of percentage values and allows individual bands of
colour values to have different percentage adjustments aplied to them. This allows
such things as lifting shadow details and suppressing highlights.</span></font></div><div align="left"><font face="Times New Roman"><span style=" font-size:12pt"><br></span></font></div><div align="left"><font face="Times New Roman"><span style=" font-size:12pt">(c) Andrew Graham - 2008</span></font></div><div align="left"> </div></body></html>
</body></html>
]]>