3 <!DOCTYPE book PUBLIC "-//Norman Walsh//DTD DocBk XML V3.1.4//EN"
4 "file:///usr/share/xml/docbook/schema/dtd/4.4/docbookx.dtd">
6 <chapter id="user-defaults">
7 <title>Default Settings</title>
9 <p>ALE offers five different default settings, each of which emphasizes
10 image quality, speed, or some other rendering characteristic, as follows:</p>
12 <ll>--q0 Low quality, high speed. [default]
13 --qn Low noise, moderate speed.
14 --q1 Moderate quality and speed.
15 --q2 High quality, low speed.
16 --qr Range-extended high quality.
19 <p>These settings specify defaults for other options: <l>--dchain</l>,
20 <l>--achain</l>, <l>--3d-chain</l>, <l>--ips</l>, <l>--exp-extend</l>, and
21 <l>--cx</l>. For more information about these options, see <xref
22 linkend="user-rendering"/> and <xref linkend="user-3d"/>. Details regarding
23 these defaults are provided in the following sections.</p>
25 <s><t>High speed (--q0)</t>
27 <p><code>--q0</code> emphasizes speed over image quality. This option is default, and
28 sets other options' defaults as follows:</p>
30 <ll>--dchain fine:box:1,triangle:2
35 --3d-chain fine:box:1,triangle:2
39 <s><t>Low noise (--qn)</t>
41 <p><code>--qn</code> emphasizes low noise over resolution and rendering speed, and
42 sets the following defaults:</p>
44 <ll>--dchain sinc*lanc:6
49 --3d-chain sinc*lanc:6
54 <s><t>Balanced quality and speed (--q1)</t>
56 <p><code>--q1</code> balances image quality and rendering speed, offering higher
57 resolution than <code>--qn</code>. As this option uses median values, its memory use
58 is linear in the number of input images (rather than constant).</p>
60 <ll>--dchain median:fine:sinc*lanc:8,triangle:2
65 --3d-chain median:fine:sinc*lanc:8,triangle:2
70 <s><t>High quality (--q2)</t>
72 <p><l>--q2</l> favors image quality over rendering speed, offering greater
73 emphasis for high-frequency details than <l>--q0</l>, <l>--qn</l>,
74 or <l>--q1</l>. It depends on the <l>--lpsf</l> and
75 <l>--nlpsf</l> options, which can be set indirectly via the
76 <l>--device</l> option. (More information about these options can be
77 found in <xref linkend="user-psf"/> and <xref linkend="user-device"/>.) <l>--q2</l>
78 sets the following defaults:</p>
80 <ll>--dchain triangle:2
85 --3d-chain median:fine:sinc*lanc:8,triangle:2
90 <s><t>Range extension (--qr)</t>
92 <p><code>--qr</code> is similar to <code>--q2</code>, but offers improved
93 rendering when input images have been taken with unequal exposures. In other
94 cases, it may exacerbate noise in light and dark regions. This option sets the
95 following defaults:</p>
97 <ll>--dchain triangle:2
102 --3d-chain median:fine:sinc*lanc:8,triangle:2