Mercurial > hg > digilib-old
changeset 80:4d0e75042673
Docu update to match Scaler servlet version 1.6b.
| author | robcast |
|---|---|
| date | Mon, 03 Feb 2003 17:00:28 +0100 |
| parents | 63c8186455c1 |
| children | c7e6d92e7fd5 |
| files | servlet/doc/Scaler.html |
| diffstat | 1 files changed, 55 insertions(+), 26 deletions(-) [+] |
line wrap: on
line diff
--- a/servlet/doc/Scaler.html Mon Feb 03 16:04:53 2003 +0100 +++ b/servlet/doc/Scaler.html Mon Feb 03 17:00:28 2003 +0100 @@ -6,55 +6,84 @@ <BODY> <H1>Scaler</H1> -<p>A Servlet for scaling images.</p> +<p>A Servlet for scaling images. (Version 1.6b)</p> + +<h2>Web API</h2> -<p>Scaler takes parameters in the http request format: -<code>Scaler/request_path/?param1=value1¶m2=value2&...</code></p> +<p>The Scaler servlet takes parameters in the http request format: +<code>Scaler/request_path/?param1=value1¶m2=value2&...</code> +Unknown parameters will be silently ignored.</p> <p>Recognised parameters: <ul> - <li><b>request_path</b> path to file or directory. + <li><b>request_path</b> path to file or directory.</li> - <li><b>fn</b> path to file or directory below <code>/docuserver/images</code>. + <li><b>fn</b> path to file or directory below <code>/docuserver/images</code> + (or other configured image directory). This path will be added to the <code>request_path</code> behind the servlet name. - Either parameter can be empty. + Either parameter can be empty.</li> <li><b>pn</b> page number. Index into the (alphabetically sorted) directory given by the path. Starts with 1. Ignored if the path points to a file. - Default: 1. + Default: 1.</li> - <li><b>dw</b> destination image width (pixels). - <li><b>dh</b> destination image height. + <li><b>dw</b> destination image width (pixels).</li> + + <li><b>dh</b> destination image height (pixels).</li> <li><b>wx</b> relative x offset of the image area to be sent (0 <= wx <= 1). - Default: 0. - <li><b>wy</b> relative y offset of the image area to be sent. - Default: 0. - <li><b>ww</b> relative width of the image area to be sent. - Default: 1. - <li><b>wh</b> relative height of the image area to be sent. - Default: 1. + Default: 0.</li> + + <li><b>wy</b> relative y offset of the image area to be sent (0 <= wy <= 1). + Default: 0.</li> + + <li><b>ww</b> relative width of the image area to be sent (0 <= ww <= 1). + Default: 1.</li> + + <li><b>wh</b> relative height of the image area to be sent (0 <= wh <= 1). + Default: 1.</li> <li><b>ws</b> additional scaling factor. The resulting image will have the size - <code>[ws*dw,ws*dh]</code>. Default: 1. + <code>[ws*dw,ws*dh]</code>. Default: 1.</li> - <li><b>mo</b> flags for the mode of operation separated by "+". + <li><b>mo</b> flags for the mode of operation separated by "+". <ul> - <li><b>fit</b>: always scale the image to fit <code>[dw,dh]</code>.<br> - <b>file</b>: send the file as-is (may be very large and all sorts of image types!).<br> - If none of these flags is set heuristics is used (send unzoomed GIF as-is). - + <li><b>fit</b>: always scale the image to fit + <code>[dw,dh]</code>.<br> <b>file</b>: send the file as-is (may + be very large and all sorts of image types!). If configuration + doesn't allow sending files + (<code>sendfile-allowed=false</code>) revert to + <code>clip</code>.<br> <b>clip</b>: send the file in its + original resolution, cropped to fit <code>[dw,dh]</code>.<br> If + none of these flags is set heuristics is used (send unzoomed GIF + as-is).</li> + <li><b>errtxt</b>: send error response as HTML.<br> - <b>errimg</b>: response as image (default). + <b>errimg</b>: response as image (default).</li> <li><b>q0</b>-<b>q2</b>: quality of interpolation in scaling - (<code>q0</code>: worst, default). + (<code>q0</code>: worst, default).</li> <li><b>lores</b>: try to use scaled image (default)<br> - <b>hires</b>: always use unscaled image.<br> - If the image is zoomed (ww, wh < 1) the unscaled image is used in any case. + <b>hires</b>: always use unscaled image.<br> + If the image is zoomed (ww, wh < 1) the unscaled image is + used in any case.</li> + + <li><b>vmir</b>: mirror image vertically.<br> + <b>hmir</b>: mirror image horizontally.</li> </ul> + </li> + <li><b>cont</b>: change contrast of the image. Negative value + reduces contrast, positive value enhances contrast. Pixel value is + multiplied by 2^cont.</li> + + <li><b>brgt</b>: change brightness of image. Negative value reduces + brightness, positive value enhances brightness. Pixel value is added + brgt.</li> + + <li><b>rot</b>: rotate image. Rotation angle is given in degrees.</li> + </ul> The image will be scaled equally in horizontal and vertical direction such that the resulting image does not exceed the rectangle <code>[ww,wh]</code>.