/usr/share/gtk-doc/html/gst-plugins-good-plugins-1.0/gst-plugins-good-plugins-alpha.html is in gstreamer1.0-plugins-good-doc 1.14.0-1ubuntu1.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 | <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>alpha: GStreamer Good Plugins 1.0 Plugins Reference Manual</title>
<meta name="generator" content="DocBook XSL Stylesheets V1.79.1">
<link rel="home" href="index.html" title="GStreamer Good Plugins 1.0 Plugins Reference Manual">
<link rel="up" href="ch01.html" title="gst-plugins-good Elements">
<link rel="prev" href="gst-plugins-good-plugins-alphacolor.html" title="alphacolor">
<link rel="next" href="gst-plugins-good-plugins-amrparse.html" title="amrparse">
<meta name="generator" content="GTK-Doc V1.27 (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">
<a href="#" class="shortcut">Top</a><span id="nav_description"> <span class="dim">|</span>
<a href="#gst-plugins-good-plugins-alpha.description" class="shortcut">Description</a></span><span id="nav_hierarchy"> <span class="dim">|</span>
<a href="#gst-plugins-good-plugins-alpha.object-hierarchy" class="shortcut">Object Hierarchy</a></span><span id="nav_properties"> <span class="dim">|</span>
<a href="#gst-plugins-good-plugins-alpha.properties" class="shortcut">Properties</a></span>
</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="gst-plugins-good-plugins-alphacolor.html"><img src="left.png" width="16" height="16" border="0" alt="Prev"></a></td>
<td><a accesskey="n" href="gst-plugins-good-plugins-amrparse.html"><img src="right.png" width="16" height="16" border="0" alt="Next"></a></td>
</tr></table>
<div class="refentry">
<a name="gst-plugins-good-plugins-alpha"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle"><a name="gst-plugins-good-plugins-alpha.top_of_page"></a>alpha</span></h2>
<p>alpha</p>
</td>
<td class="gallery_image" valign="top" align="right"></td>
</tr></table></div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-alpha.properties"></a><h2>Properties</h2>
<div class="informaltable"><table class="informaltable" border="0">
<colgroup>
<col width="150px" class="properties_type">
<col width="300px" class="properties_name">
<col width="200px" class="properties_flags">
</colgroup>
<tbody>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--alpha" title="The “alpha” property">alpha</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#gfloat"><span class="type">gfloat</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--angle" title="The “angle” property">angle</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlphaMethod" title="enum GstAlphaMethod"><span class="type">GstAlphaMethod</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--method" title="The “method” property">method</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#gfloat"><span class="type">gfloat</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--noise-level" title="The “noise-level” property">noise-level</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--target-b" title="The “target-b” property">target-b</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--target-g" title="The “target-g” property">target-g</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--target-r" title="The “target-r” property">target-r</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--black-sensitivity" title="The “black-sensitivity” property">black-sensitivity</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--white-sensitivity" title="The “white-sensitivity” property">white-sensitivity</a></td>
<td class="property_flags">Read / Write</td>
</tr>
<tr>
<td class="property_type"><a href="../glib/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></td>
<td class="property_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha--prefer-passthrough" title="The “prefer-passthrough” property">prefer-passthrough</a></td>
<td class="property_flags">Read / Write</td>
</tr>
</tbody>
</table></div>
</div>
<a name="GstAlpha"></a><div class="refsect1">
<a name="gst-plugins-good-plugins-alpha.other"></a><h2>Types and Values</h2>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="150px" class="name">
<col class="description">
</colgroup>
<tbody>
<tr>
<td class="datatype_keyword">struct</td>
<td class="function_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlpha-struct" title="struct GstAlpha">GstAlpha</a></td>
</tr>
<tr>
<td class="datatype_keyword">enum</td>
<td class="function_name"><a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlphaMethod" title="enum GstAlphaMethod">GstAlphaMethod</a></td>
</tr>
</tbody>
</table></div>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-alpha.object-hierarchy"></a><h2>Object Hierarchy</h2>
<pre class="screen"> <a href="../gobject/gobject-The-Base-Object-Type.html#GObject-struct">GObject</a>
<span class="lineart">╰──</span> <a href="../gobject/gobject-The-Base-Object-Type.html#GInitiallyUnowned">GInitiallyUnowned</a>
<span class="lineart">╰──</span> <a href="../gstreamer-1.0/GstObject.html#GstObject-struct">GstObject</a>
<span class="lineart">╰──</span> <a href="../gstreamer-1.0/GstElement.html#GstElement-struct">GstElement</a>
<span class="lineart">╰──</span> <a href="../gstreamer-libs-1.0/GstBaseTransform.html#GstBaseTransform-struct">GstBaseTransform</a>
<span class="lineart">╰──</span> <a href="../gst-plugins-base-libs-1.0/GstVideoFilter.html#GstVideoFilter-struct">GstVideoFilter</a>
<span class="lineart">╰──</span> GstAlpha
</pre>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-alpha.description"></a><h2>Description</h2>
<p>The alpha element adds an alpha channel to a video stream. The values
of the alpha channel can be either be set to a constant or can be
dynamically calculated via chroma keying, e.g. blue can be set as
the transparent color.</p>
<p>Sample pipeline:</p>
<div class="informalexample">
<table class="listing_frame" border="0" cellpadding="0" cellspacing="0">
<tbody>
<tr>
<td class="listing_lines" align="right"><pre>1
2
3
4</pre></td>
<td class="listing_code"><pre class="programlisting">gst<span class="gtkdoc opt">-</span>launch<span class="gtkdoc opt">-</span><span class="number">1.0</span> videotestsrc pattern<span class="gtkdoc opt">=</span>snow <span class="gtkdoc opt">!</span> mixer<span class="gtkdoc opt">.</span>sink_0 \
videotestsrc pattern<span class="gtkdoc opt">=</span>smpte75 <span class="gtkdoc opt">!</span> alpha method<span class="gtkdoc opt">=</span>green <span class="gtkdoc opt">!</span> mixer<span class="gtkdoc opt">.</span>sink_1 \
videomixer name<span class="gtkdoc opt">=</span>mixer <span class="gtkdoc kwc">sink_0</span><span class="gtkdoc opt">::</span>zorder<span class="gtkdoc opt">=</span><span class="number">0</span> <span class="gtkdoc kwc">sink_1</span><span class="gtkdoc opt">::</span>zorder<span class="gtkdoc opt">=</span><span class="number">1</span> <span class="gtkdoc opt">!</span> \
videoconvert <span class="gtkdoc opt">!</span> autovideosink</pre></td>
</tr>
</tbody>
</table>
</div>
<p> This pipeline adds a alpha channel to the SMPTE color bars
with green as the transparent color and overlays the output on
top of a snow video stream.</p>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<div class="refsect2">
<a name="id-1.2.10.7.6.1"></a><h3>Element Information</h3>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">plugin</span></p></td>
<td>
<a class="link" href="gst-plugins-good-plugins-plugin-alpha.html#plugin-alpha">alpha</a>
</td>
</tr>
<tr>
<td><p><span class="term">author</span></p></td>
<td>Wim Taymans <wim.taymans@gmail.com>
Edward Hervey <edward.hervey@collabora.co.uk>
Jan Schmidt <thaytan@noraisin.net></td>
</tr>
<tr>
<td><p><span class="term">class</span></p></td>
<td>Filter/Effect/Video</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2">
<a name="id-1.2.10.7.6.2"></a><h3>Element Pads</h3>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">name</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">direction</span></p></td>
<td>sink</td>
</tr>
<tr>
<td><p><span class="term">presence</span></p></td>
<td>always</td>
</tr>
<tr>
<td><p><span class="term">details</span></p></td>
<td>video/x-raw, format=(string){ AYUV, ARGB, BGRA, ABGR, RGBA, Y444, xRGB, BGRx, xBGR, RGBx, RGB, BGR, Y42B, YUY2, YVYU, UYVY, I420, YV12, Y41B }, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]</td>
</tr>
</tbody>
</table></div>
<div class="variablelist"><table border="0" class="variablelist">
<colgroup>
<col align="left" valign="top">
<col>
</colgroup>
<tbody>
<tr>
<td><p><span class="term">name</span></p></td>
<td>src</td>
</tr>
<tr>
<td><p><span class="term">direction</span></p></td>
<td>source</td>
</tr>
<tr>
<td><p><span class="term">presence</span></p></td>
<td>always</td>
</tr>
<tr>
<td><p><span class="term">details</span></p></td>
<td>video/x-raw, format=(string){ AYUV, ARGB, BGRA, ABGR, RGBA, Y444, xRGB, BGRx, xBGR, RGBx, RGB, BGR, Y42B, YUY2, YVYU, UYVY, I420, YV12, Y41B }, width=(int)[ 1, 2147483647 ], height=(int)[ 1, 2147483647 ], framerate=(fraction)[ 0/1, 2147483647/1 ]</td>
</tr>
</tbody>
</table></div>
</div>
</div>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-alpha.functions_details"></a><h2>Functions</h2>
<p></p>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-alpha.other_details"></a><h2>Types and Values</h2>
<div class="refsect2">
<a name="GstAlpha-struct"></a><h3>struct GstAlpha</h3>
<pre class="programlisting">struct GstAlpha;</pre>
</div>
<hr>
<div class="refsect2">
<a name="GstAlphaMethod"></a><h3>enum GstAlphaMethod</h3>
<div class="refsect3">
<a name="GstAlphaMethod.members"></a><h4>Members</h4>
<div class="informaltable"><table class="informaltable" width="100%" border="0">
<colgroup>
<col width="300px" class="enum_members_name">
<col class="enum_members_description">
<col width="200px" class="enum_members_annotations">
</colgroup>
<tbody>
<tr>
<td class="enum_member_name"><p><a name="ALPHA-METHOD-SET:CAPS"></a>ALPHA_METHOD_SET</p></td>
<td class="enum_member_description">
<p>Set/adjust alpha channel</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="ALPHA-METHOD-GREEN:CAPS"></a>ALPHA_METHOD_GREEN</p></td>
<td class="enum_member_description">
<p>Chroma Key green</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="ALPHA-METHOD-BLUE:CAPS"></a>ALPHA_METHOD_BLUE</p></td>
<td class="enum_member_description">
<p>Chroma Key blue</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
<tr>
<td class="enum_member_name"><p><a name="ALPHA-METHOD-CUSTOM:CAPS"></a>ALPHA_METHOD_CUSTOM</p></td>
<td class="enum_member_description">
<p>Chroma Key on target_r/g/b</p>
</td>
<td class="enum_member_annotations"> </td>
</tr>
</tbody>
</table></div>
</div>
</div>
</div>
<div class="refsect1">
<a name="gst-plugins-good-plugins-alpha.property-details"></a><h2>Property Details</h2>
<div class="refsect2">
<a name="GstAlpha--alpha"></a><h3>The <code class="literal">“alpha”</code> property</h3>
<pre class="programlisting"> “alpha” <a href="../glib/glib-Basic-Types.html#gdouble"><span class="type">gdouble</span></a></pre>
<p>The value for the alpha channel.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: [0,1]</p>
<p>Default value: 1</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--angle"></a><h3>The <code class="literal">“angle”</code> property</h3>
<pre class="programlisting"> “angle” <a href="../glib/glib-Basic-Types.html#gfloat"><span class="type">gfloat</span></a></pre>
<p>Size of the colorcube to change.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: [0,90]</p>
<p>Default value: 20</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--method"></a><h3>The <code class="literal">“method”</code> property</h3>
<pre class="programlisting"> “method” <a class="link" href="gst-plugins-good-plugins-alpha.html#GstAlphaMethod" title="enum GstAlphaMethod"><span class="type">GstAlphaMethod</span></a></pre>
<p>How the alpha channels should be created.</p>
<p>Flags: Read / Write</p>
<p>Default value: Set/adjust alpha channel</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--noise-level"></a><h3>The <code class="literal">“noise-level”</code> property</h3>
<pre class="programlisting"> “noise-level” <a href="../glib/glib-Basic-Types.html#gfloat"><span class="type">gfloat</span></a></pre>
<p>Size of noise radius.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: [0,64]</p>
<p>Default value: 2</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--target-b"></a><h3>The <code class="literal">“target-b”</code> property</h3>
<pre class="programlisting"> “target-b” <a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></pre>
<p>The blue color value for custom RGB chroma keying.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: <= 255</p>
<p>Default value: 0</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--target-g"></a><h3>The <code class="literal">“target-g”</code> property</h3>
<pre class="programlisting"> “target-g” <a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></pre>
<p>The green color value for custom RGB chroma keying.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: <= 255</p>
<p>Default value: 255</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--target-r"></a><h3>The <code class="literal">“target-r”</code> property</h3>
<pre class="programlisting"> “target-r” <a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></pre>
<p>The red color value for custom RGB chroma keying.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: <= 255</p>
<p>Default value: 0</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--black-sensitivity"></a><h3>The <code class="literal">“black-sensitivity”</code> property</h3>
<pre class="programlisting"> “black-sensitivity” <a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></pre>
<p>Sensitivity to dark colors.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: <= 128</p>
<p>Default value: 100</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--white-sensitivity"></a><h3>The <code class="literal">“white-sensitivity”</code> property</h3>
<pre class="programlisting"> “white-sensitivity” <a href="../glib/glib-Basic-Types.html#guint"><span class="type">guint</span></a></pre>
<p>Sensitivity to bright colors.</p>
<p>Flags: Read / Write</p>
<p>Allowed values: <= 128</p>
<p>Default value: 100</p>
</div>
<hr>
<div class="refsect2">
<a name="GstAlpha--prefer-passthrough"></a><h3>The <code class="literal">“prefer-passthrough”</code> property</h3>
<pre class="programlisting"> “prefer-passthrough” <a href="../glib/glib-Basic-Types.html#gboolean"><span class="type">gboolean</span></a></pre>
<p>Don't do any processing for alpha=1.0 if possible.</p>
<p>Flags: Read / Write</p>
<p>Default value: FALSE</p>
</div>
</div>
</div>
<div class="footer">
<hr>Generated by GTK-Doc V1.27</div>
</body>
</html>
|