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updated doc
author robcast
date Tue, 02 Nov 2004 14:31:58 +0100
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1 <!doctype html public "-//w3c//dtd html 4.0 transitional//en"> 1 <!doctype html public "-//w3c//dtd html 4.0 transitional//en">
2 <html> 2 <html>
3 <head> 3 <head>
4 <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> 4 <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
5 <TITLE>Scaler servlet</TITLE> 5 <title>Scaler servlet</title>
6 </head> 6 </head>
7 <BODY> 7 <body>
8 <H1>Scaler</H1> 8 <h1>Scaler</h1>
9 9
10 <p>A Servlet for scaling images. (Version 1.16b2)</p> 10 <p>A Servlet for scaling images. (Version 1.5.2)</p>
11 11
12 <h2>Web API</h2> 12 <h2>Web API</h2>
13 13
14 <p>The Scaler servlet takes parameters in the http request format: 14 <p>The Scaler servlet takes parameters in the http request format:
15 <code>Scaler/request_path/?param1=value1&param2=value2&...</code> 15 <code>Scaler/request_path/?param1=value1&amp;param2=value2&amp;...</code>
16 Unknown parameters will be silently ignored.</p> 16 Unknown parameters will be silently ignored.</p>
17 17
18 <p>Recognised parameters:</p> 18 <p>Recognised parameters:</p>
19 <ul> 19 <ul>
20 <li><b>request_path</b> path to file or directory.</li> 20 <li><b>request_path</b> path to file or directory.</li>
50 <code>[ws*dw,ws*dh]</code>. Default: 1.</li> 50 <code>[ws*dw,ws*dh]</code>. Default: 1.</li>
51 51
52 <li><b>mo</b> flags for the mode of operation separated by ",". 52 <li><b>mo</b> flags for the mode of operation separated by ",".
53 <ul> 53 <ul>
54 <li><b>fit</b>: always scale the image to fit 54 <li><b>fit</b>: always scale the image to fit
55 <code>[dw,dh]</code>.<br> 55 <code>[dw,dh]</code> (default).<br>
56
57 <b>clip</b>: send the file in its
58 original resolution, cropped to fit <code>[dw,dh]</code>.
59 <br>
56 60
61 <b>osize</b>: scale to original size based on the image resolution
62 (from the image metadata) and display resolution (from parameter
63 <code>ddpi</code>). Fails if either resolution is unknown.
64 </li>
65
66 <li>
57 <b>file</b>: send the file as-is (may 67 <b>file</b>: send the file as-is (may
58 be very large and all sorts of image types!). If configuration 68 be very large and all sorts of image types!). If configuration
59 doesn't allow sending files 69 doesn't allow sending files
60 (<code>sendfile-allowed=false</code>) revert to 70 (<code>sendfile-allowed=false</code>) revert to
61 <code>clip</code>.<br> 71 <code>clip</code>.<br>
62 72
63 <b>rawfile</b>: send the file as-is with a mime-type of 73 <b>rawfile</b>: send the file as-is with a mime-type of
64 <code>application/octet-stream</code> so it can be downloaded with 74 <code>application/octet-stream</code> so it can be downloaded with
65 the browser.<br> 75 the browser.
66
67 <b>clip</b>: send the file in its
68 original resolution, cropped to fit <code>[dw,dh]</code>.<br> If
69 none of these flags is set heuristics is used (send unzoomed GIF
70 as-is).<br>
71
72 <b>osize</b>: scale to original size based on the image resolution
73 (from the image metadata) and display resolution (from parameter
74 <code>ddpi</code>). Fails if either resolution is unknown.
75 </li> 76 </li>
76 77
77 <li><b>errtxt</b>: send error response as HTML.<br> 78 <li><b>errtxt</b>: send error response as HTML.<br>
78 <b>errimg</b>: response as image (default).</li> 79 <b>errimg</b>: response as image (default).</li>
79 80
82 83
83 <li><b>lores</b>: try to use scaled image (default)<br> 84 <li><b>lores</b>: try to use scaled image (default)<br>
84 85
85 <b>hires</b>: always use unscaled image.<br> 86 <b>hires</b>: always use unscaled image.<br>
86 87
87 If the image is zoomed (ww, wh &lt; 1) the unscaled image is 88 If the image is zoomed (ww, wh &lt; 1) the use of the scaled
88 used in any case.</li> 89 image files depends on the requested resolution.</li>
89 90
90 <li><b>vmir</b>: mirror image vertically.<br> 91 <li><b>vmir</b>: mirror image vertically.<br>
91 92
92 <b>hmir</b>: mirror image horizontally.</li> 93 <b>hmir</b>: mirror image horizontally.</li>
94
95 <li><b>jpg</b>: the resulting image is always sent as JPEG
96 (otherwise TIFF and PNG images are sent as PNG).
97 </li>
93 </ul> 98 </ul>
94 </li> 99 </li>
95 100
96 <li><b>cont</b>: change contrast of the image. Negative value 101 <li><b>cont</b>: change contrast of the image. Negative value
97 reduces contrast, positive value enhances contrast. Pixel value is 102 reduces contrast, positive value enhances contrast. Pixel value is
146 image is scaled to match only the given parameter. The size of the 151 image is scaled to match only the given parameter. The size of the
147 resulting image in the other parameter is determined by the aspect 152 resulting image in the other parameter is determined by the aspect
148 ratio of the image. 153 ratio of the image.
149 </p> 154 </p>
150 155
151 </BODY> 156 </body>
152 </html> 157 </html>