libvips-doc 8.4.5-1build1 / usr / share / gtk-doc / html / libvips / using-cli.html

This file is indexed.

/usr/share/gtk-doc/html/libvips/using-cli.html is in libvips-doc 8.4.5-1build1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below. 

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>VIPS from the command-line: VIPS Reference Manual</title>
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="index.html" title="VIPS Reference Manual">
<link rel="up" href="ch01.html" title="VIPS Overview">
<link rel="prev" href="ch01.html" title="VIPS Overview">
<link rel="next" href="using-from-c.html" title="VIPS from C">
<meta name="generator" content="GTK-Doc V1.25 (XML mode)">
<link rel="stylesheet" href="style.css" type="text/css">
</head>
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="5"><tr valign="middle">
<td width="100%" align="left" class="shortcuts"></td>
<td><a accesskey="h" href="index.html"><img src="home.png" width="16" height="16" border="0" alt="Home"></a></td>
<td><a accesskey="u" href="ch01.html"><img src="up.png" width="16" height="16" border="0" alt="Up"></a></td>
<td><a accesskey="p" href="ch01.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td>
<td><a accesskey="n" href="using-from-c.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td>
</tr></table>
<div class="refentry">
<a name="using-cli"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle">VIPS from the command-line</span></h2>
<p>Using VIPS — How to use the VIPS library from the command-line</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect3">
<a name="using-command-line-intro"></a><h4>Introduction</h4>
<p>
      Use the <span class="command"><strong>vips</strong></span> command to execute VIPS operations from 
      the command-line. For example:

</p>
<pre class="programlisting">
$ vips rot k2.jpg x.jpg d90
</pre>
<p>

      Will rotate the image <code class="literal">k2.jpg</code> by 90 degrees 
      anticlockwise and write the result to the file <code class="literal">x.jpg</code>. 
      If you don't give any arguments to an operation, 
      <span class="command"><strong>vips</strong></span> will give a short description, for example:

</p>
<pre class="programlisting">
$ vips rot 
rotate an image
usage:
   rot in out angle
where:
   in           - Input image, input VipsImage
   out          - Output image, output VipsImage
   angle        - Angle to rotate image, input VipsAngle
                        default: d90
                        allowed: d0, d90, d180, d270
</pre>
<p>

      There's a straightforward relationship with the C API: compare this to 
      the API docs for <a class="link" href="libvips-conversion.html#vips-rot" title="vips_rot ()"><code class="function">vips_rot()</code></a>, for example.
    </p>
</div>
<div class="refsect3">
<a name="using-command-line-list"></a><h4>Listing all operations</h4>
<p>
      You can list all classes with:

</p>
<pre class="programlisting">
$ vips -l
... 
VipsOperation (operation), operations
  VipsSystem (system), run an external command
  VipsArithmetic (arithmetic), arithmetic operations
    VipsBinary (binary), binary operations
      VipsAdd (add), add two images
      ... etc.
</pre>
<p>

      Each line shows the canonical name of the class (for example 
      <code class="literal">VipsAdd</code>), the class nickname 
      (<code class="literal">add</code> in this case), and a short description. 
      Some subclasses of operation will show more: for example, subclasses of 
      <code class="literal">VipsForeign</code> will show some of the extra flags 
      supported by the file load/save operations. 
    </p>
</div>
<div class="refsect3">
<a name="using-command-line-options"></a><h4>Optional arguments</h4>
<p>
      Many operations take optional arguments. You can supply these as 
      command-line options, for example:

</p>
<pre class="programlisting">
$ vips gamma
gamma an image
usage:
   gamma in out
where:
   in           - Input image, input VipsImage
   out          - Output image, output VipsImage
optional arguments:
   exponent     - Gamma factor, input gdouble
                  default: 2.4
                  min: 1e-06, max: 1000
operation flags: sequential-unbuffered 
</pre>
<p>

      <a class="link" href="libvips-conversion.html#vips-gamma" title="vips_gamma ()"><code class="function">vips_gamma()</code></a> applies a gamma factor to an image. By 
      default, it uses 2.4, the sRGB gamma factor, but you can specify any 
      gamma with the <code class="literal">exponent</code> option. 
    </p>
<p>
      Use it from the command-line like this:

</p>
<pre class="programlisting">
$ vips gamma k2.jpg x.jpg --exponent 0.42
</pre>
<p>

      This will read file <code class="literal">k2.jpg</code>, un-gamma it, and 
      write the result to file <code class="literal">x.jpg</code>.
    </p>
</div>
<div class="refsect3">
<a name="using-command-line-array"></a><h4>Array arguments</h4>
<p>
      Some operations take arrays of values as arguments, for example, 
      <a class="link" href="libvips-resample.html#vips-affine" title="vips_affine ()"><code class="function">vips_affine()</code></a> needs an array of four numbers for the 
      2x2 transform matrix. You pass arrays as space-separated lists, for 
      example:

</p>
<pre class="programlisting">
$ vips affine k2.jpg x.jpg "2 0 0 1"
</pre>
<p>

      You may need the quotes to stop your shell breaking the argument at 
      the spaces. <a class="link" href="libvips-conversion.html#vips-bandjoin" title="vips_bandjoin ()"><code class="function">vips_bandjoin()</code></a> needs an array of input images to 
      join, run it like this:

</p>
<pre class="programlisting">
$ vips bandjoin "k2.jpg k4.jpg" x.tif
</pre>
<p>
    </p>
</div>
<div class="refsect3">
<a name="using-command-line-conversion"></a><h4>Implicit file format conversion</h4>
<p>
      <span class="command"><strong>vips</strong></span> will automatically convert between image file 
      formats for you. Input images are detected by sniffing their first few 
      bytes; output formats are set from the filename suffix. You can see a 
      list of all the supported file formats with something like:

</p>
<pre class="programlisting">
$ vips -l foreign
</pre>
<p>

      Then get a list of the options a format supports with, for example:

</p>
<pre class="programlisting">
$ vips jpegsave
</pre>
<p>
    </p>
<p>
      You can pass options to the implicit load and save operations enclosed 
      in square brackets after the filename. For example:

</p>
<pre class="programlisting">
vips affine k2.jpg x.jpg[Q=90,strip] "2 0 0 1"
</pre>
<p>

      Will write <code class="literal">x.jpg</code> at quality level 90 and will 
      strip all metadata from the image.
    </p>
</div>
<div class="refsect3">
<a name="using-command-line-chaining"></a><h4>Chaining operations</h4>
<p>
      Because each operation runs in a separate process, you can't use 
      libvips's chaining system to join operations together, you have to use 
      intermediate files. The command-line interface is therefore quite a bit 
      slower than Python or C. 
    </p>
<p>
      The best alternative is to use vips files for intermediates. 
      Something like:

</p>
<pre class="programlisting">
vips invert input.jpg t1.v
vips affine t1.v output.jpg "2 0 0 1"
rm t1.v
</pre>
<p>
    </p>
</div>
<div class="refsect3">
<a name="using-command-line-other"></a><h4>Other features</h4>
<p>
      Finally, <span class="command"><strong>vips</strong></span> has a couple of useful extra options. 

      </p>
<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; ">
<li class="listitem"><p>
            Use <code class="option">--vips-progress</code> to get 
            <span class="command"><strong>vips</strong></span> to display a simple progress indicator. 
          </p></li>
<li class="listitem"><p>
            Use <code class="option">--vips-leak</code> and <span class="command"><strong>vips</strong></span> will 
            leak-test on exit, and also display an estimate of peak memory use.
          </p></li>
</ul></div>
<p>
    </p>
<p>
      VIPS comes with a couple of other useful programs. 
      <span class="command"><strong>vipsheader</strong></span> is a command which can print image header
      fields. <span class="command"><strong>vipsedit</strong></span> can change fields in vips format 
      images. <span class="command"><strong>vipsthumbnail</strong></span> can make image thumbnails 
      quickly. 
    </p>
</div>
</div>
<div class="footer">
<hr>Generated by GTK-Doc V1.25</div>
</body>
</html>

APT Browse - Built by Thomas Orozco.