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  28. 

  29. <h1 class="titlefont">FFmpeg Utilities Documentation</h1>

  30. <hr>

  31. <a name="SEC_Top"></a>

  32. 

  33. <a name="SEC_Contents"></a>

  34. <h1>Table of Contents</h1>

  35. 

  36. <div class="contents">

  37. 

  38. <ul class="no-bullet">

  39.   <li><a name="toc-Description" href="#Description">1 Description</a></li>

  40.   <li><a name="toc-Syntax" href="#Syntax">2 Syntax</a>

  41.   <ul class="no-bullet">

  42.     <li><a name="toc-Quoting-and-escaping" href="#Quoting-and-escaping">2.1 Quoting and escaping</a>

  43.     <ul class="no-bullet">

  44.       <li><a name="toc-Examples" href="#Examples">2.1.1 Examples</a></li>

  45.     </ul></li>

  46.     <li><a name="toc-Date" href="#Date">2.2 Date</a></li>

  47.     <li><a name="toc-Time-duration" href="#Time-duration">2.3 Time duration</a>

  48.     <ul class="no-bullet">

  49.       <li><a name="toc-Examples-1" href="#Examples-1">2.3.1 Examples</a></li>

  50.     </ul></li>

  51.     <li><a name="toc-Video-size" href="#Video-size">2.4 Video size</a></li>

  52.     <li><a name="toc-Video-rate" href="#Video-rate">2.5 Video rate</a></li>

  53.     <li><a name="toc-Ratio" href="#Ratio">2.6 Ratio</a></li>

  54.     <li><a name="toc-Color" href="#Color">2.7 Color</a></li>

  55.     <li><a name="toc-Channel-Layout" href="#Channel-Layout">2.8 Channel Layout</a></li>

  56.   </ul></li>

  57.   <li><a name="toc-Expression-Evaluation" href="#Expression-Evaluation">3 Expression Evaluation</a></li>

  58.   <li><a name="toc-See-Also" href="#See-Also">4 See Also</a></li>

  59.   <li><a name="toc-Authors" href="#Authors">5 Authors</a></li>

  60. </ul>

  61. </div>

  62. 

  63. 

  64. <hr size="6">

  65. <a name="Description"></a>

  66. <h1 class="chapter"><a href="ffmpeg-utils.html#toc-Description">1 Description</a></h1>

  67. 

  68. <p>This document describes some generic features and utilities provided

  69. by the libavutil library.

  70. </p>

  71. 

  72. <a name="Syntax"></a>

  73. <h1 class="chapter"><a href="ffmpeg-utils.html#toc-Syntax">2 Syntax</a></h1>

  74. 

  75. <p>This section documents the syntax and formats employed by the FFmpeg

  76. libraries and tools.

  77. </p>

  78. <p><a name="quoting_005fand_005fescaping"></a>

  79. </p><a name="Quoting-and-escaping"></a>

  80. <h2 class="section"><a href="ffmpeg-utils.html#toc-Quoting-and-escaping">2.1 Quoting and escaping</a></h2>

  81. 

  82. <p>FFmpeg adopts the following quoting and escaping mechanism, unless

  83. explicitly specified. The following rules are applied:

  84. </p>

  85. <ul>

  86. <li>

  87. &lsquo;<samp>'</samp>&rsquo; and &lsquo;<samp>\</samp>&rsquo; are special characters (respectively used for

  88. quoting and escaping). In addition to them, there might be other

  89. special characters depending on the specific syntax where the escaping

  90. and quoting are employed.

  91. 

  92. </li><li>

  93. A special character is escaped by prefixing it with a &lsquo;<samp>\</samp>&rsquo;.

  94. 

  95. </li><li>

  96. All characters enclosed between &lsquo;<samp>''</samp>&rsquo; are included literally in the

  97. parsed string. The quote character &lsquo;<samp>'</samp>&rsquo; itself cannot be quoted,

  98. so you may need to close the quote and escape it.

  99. 

  100. </li><li>

  101. Leading and trailing whitespaces, unless escaped or quoted, are

  102. removed from the parsed string.

  103. </li></ul>

  104. 

  105. <p>Note that you may need to add a second level of escaping when using

  106. the command line or a script, which depends on the syntax of the

  107. adopted shell language.

  108. </p>

  109. <p>The function <code>av_get_token</code> defined in

  110. &lsquo;<tt>libavutil/avstring.h</tt>&rsquo; can be used to parse a token quoted or

  111. escaped according to the rules defined above.

  112. </p>

  113. <p>The tool &lsquo;<tt>tools/ffescape</tt>&rsquo; in the FFmpeg source tree can be used

  114. to automatically quote or escape a string in a script.

  115. </p>

  116. <a name="Examples"></a>

  117. <h3 class="subsection"><a href="ffmpeg-utils.html#toc-Examples">2.1.1 Examples</a></h3>

  118. 

  119. <ul>

  120. <li>

  121. Escape the string <code>Crime d'Amour</code> containing the <code>'</code> special

  122. character:

  123. <div class="example">

  124. <pre class="example">Crime d\'Amour

  125. </pre></div>

  126. 

  127. </li><li>

  128. The string above contains a quote, so the <code>'</code> needs to be escaped

  129. when quoting it:

  130. <div class="example">

  131. <pre class="example">'Crime d'\''Amour'

  132. </pre></div>

  133. 

  134. </li><li>

  135. Include leading or trailing whitespaces using quoting:

  136. <div class="example">

  137. <pre class="example">'  this string starts and ends with whitespaces  '

  138. </pre></div>

  139. 

  140. </li><li>

  141. Escaping and quoting can be mixed together:

  142. <div class="example">

  143. <pre class="example">' The string '\'string\'' is a string '

  144. </pre></div>

  145. 

  146. </li><li>

  147. To include a literal &lsquo;<samp>\</samp>&rsquo; you can use either escaping or quoting:

  148. <div class="example">

  149. <pre class="example">'c:\foo' can be written as c:\\foo

  150. </pre></div>

  151. </li></ul>

  152. 

  153. <p><a name="date-syntax"></a>

  154. </p><a name="Date"></a>

  155. <h2 class="section"><a href="ffmpeg-utils.html#toc-Date">2.2 Date</a></h2>

  156. 

  157. <p>The accepted syntax is:

  158. </p><div class="example">

  159. <pre class="example">[(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...]]])|(HHMMSS[.m...]]]))[Z]

  160. now

  161. </pre></div>

  162. 

  163. <p>If the value is &quot;now&quot; it takes the current time.

  164. </p>

  165. <p>Time is local time unless Z is appended, in which case it is

  166. interpreted as UTC.

  167. If the year-month-day part is not specified it takes the current

  168. year-month-day.

  169. </p>

  170. <p><a name="time-duration-syntax"></a>

  171. </p><a name="Time-duration"></a>

  172. <h2 class="section"><a href="ffmpeg-utils.html#toc-Time-duration">2.3 Time duration</a></h2>

  173. 

  174. <p>There are two accepted syntaxes for expressing time duration.

  175. </p>

  176. <div class="example">

  177. <pre class="example">[-][<var>HH</var>:]<var>MM</var>:<var>SS</var>[.<var>m</var>...]

  178. </pre></div>

  179. 

  180. <p><var>HH</var> expresses the number of hours, <var>MM</var> the number of minutes

  181. for a maximum of 2 digits, and <var>SS</var> the number of seconds for a

  182. maximum of 2 digits. The <var>m</var> at the end expresses decimal value for

  183. <var>SS</var>.

  184. </p>

  185. <p><em>or</em>

  186. </p>

  187. <div class="example">

  188. <pre class="example">[-]<var>S</var>+[.<var>m</var>...]

  189. </pre></div>

  190. 

  191. <p><var>S</var> expresses the number of seconds, with the optional decimal part

  192. <var>m</var>.

  193. </p>

  194. <p>In both expressions, the optional &lsquo;<samp>-</samp>&rsquo; indicates negative duration.

  195. </p>

  196. <a name="Examples-1"></a>

  197. <h3 class="subsection"><a href="ffmpeg-utils.html#toc-Examples-1">2.3.1 Examples</a></h3>

  198. 

  199. <p>The following examples are all valid time duration:

  200. </p>

  201. <dl compact="compact">

  202. <dt>&lsquo;<samp>55</samp>&rsquo;</dt>

  203. <dd><p>55 seconds

  204. </p>

  205. </dd>

  206. <dt>&lsquo;<samp>12:03:45</samp>&rsquo;</dt>

  207. <dd><p>12 hours, 03 minutes and 45 seconds

  208. </p>

  209. </dd>

  210. <dt>&lsquo;<samp>23.189</samp>&rsquo;</dt>

  211. <dd><p>23.189 seconds

  212. </p></dd>

  213. </dl>

  214. 

  215. <p><a name="video-size-syntax"></a>

  216. </p><a name="Video-size"></a>

  217. <h2 class="section"><a href="ffmpeg-utils.html#toc-Video-size">2.4 Video size</a></h2>

  218. <p>Specify the size of the sourced video, it may be a string of the form

  219. <var>width</var>x<var>height</var>, or the name of a size abbreviation.

  220. </p>

  221. <p>The following abbreviations are recognized:

  222. </p><dl compact="compact">

  223. <dt>&lsquo;<samp>ntsc</samp>&rsquo;</dt>

  224. <dd><p>720x480

  225. </p></dd>

  226. <dt>&lsquo;<samp>pal</samp>&rsquo;</dt>

  227. <dd><p>720x576

  228. </p></dd>

  229. <dt>&lsquo;<samp>qntsc</samp>&rsquo;</dt>

  230. <dd><p>352x240

  231. </p></dd>

  232. <dt>&lsquo;<samp>qpal</samp>&rsquo;</dt>

  233. <dd><p>352x288

  234. </p></dd>

  235. <dt>&lsquo;<samp>sntsc</samp>&rsquo;</dt>

  236. <dd><p>640x480

  237. </p></dd>

  238. <dt>&lsquo;<samp>spal</samp>&rsquo;</dt>

  239. <dd><p>768x576

  240. </p></dd>

  241. <dt>&lsquo;<samp>film</samp>&rsquo;</dt>

  242. <dd><p>352x240

  243. </p></dd>

  244. <dt>&lsquo;<samp>ntsc-film</samp>&rsquo;</dt>

  245. <dd><p>352x240

  246. </p></dd>

  247. <dt>&lsquo;<samp>sqcif</samp>&rsquo;</dt>

  248. <dd><p>128x96

  249. </p></dd>

  250. <dt>&lsquo;<samp>qcif</samp>&rsquo;</dt>

  251. <dd><p>176x144

  252. </p></dd>

  253. <dt>&lsquo;<samp>cif</samp>&rsquo;</dt>

  254. <dd><p>352x288

  255. </p></dd>

  256. <dt>&lsquo;<samp>4cif</samp>&rsquo;</dt>

  257. <dd><p>704x576

  258. </p></dd>

  259. <dt>&lsquo;<samp>16cif</samp>&rsquo;</dt>

  260. <dd><p>1408x1152

  261. </p></dd>

  262. <dt>&lsquo;<samp>qqvga</samp>&rsquo;</dt>

  263. <dd><p>160x120

  264. </p></dd>

  265. <dt>&lsquo;<samp>qvga</samp>&rsquo;</dt>

  266. <dd><p>320x240

  267. </p></dd>

  268. <dt>&lsquo;<samp>vga</samp>&rsquo;</dt>

  269. <dd><p>640x480

  270. </p></dd>

  271. <dt>&lsquo;<samp>svga</samp>&rsquo;</dt>

  272. <dd><p>800x600

  273. </p></dd>

  274. <dt>&lsquo;<samp>xga</samp>&rsquo;</dt>

  275. <dd><p>1024x768

  276. </p></dd>

  277. <dt>&lsquo;<samp>uxga</samp>&rsquo;</dt>

  278. <dd><p>1600x1200

  279. </p></dd>

  280. <dt>&lsquo;<samp>qxga</samp>&rsquo;</dt>

  281. <dd><p>2048x1536

  282. </p></dd>

  283. <dt>&lsquo;<samp>sxga</samp>&rsquo;</dt>

  284. <dd><p>1280x1024

  285. </p></dd>

  286. <dt>&lsquo;<samp>qsxga</samp>&rsquo;</dt>

  287. <dd><p>2560x2048

  288. </p></dd>

  289. <dt>&lsquo;<samp>hsxga</samp>&rsquo;</dt>

  290. <dd><p>5120x4096

  291. </p></dd>

  292. <dt>&lsquo;<samp>wvga</samp>&rsquo;</dt>

  293. <dd><p>852x480

  294. </p></dd>

  295. <dt>&lsquo;<samp>wxga</samp>&rsquo;</dt>

  296. <dd><p>1366x768

  297. </p></dd>

  298. <dt>&lsquo;<samp>wsxga</samp>&rsquo;</dt>

  299. <dd><p>1600x1024

  300. </p></dd>

  301. <dt>&lsquo;<samp>wuxga</samp>&rsquo;</dt>

  302. <dd><p>1920x1200

  303. </p></dd>

  304. <dt>&lsquo;<samp>woxga</samp>&rsquo;</dt>

  305. <dd><p>2560x1600

  306. </p></dd>

  307. <dt>&lsquo;<samp>wqsxga</samp>&rsquo;</dt>

  308. <dd><p>3200x2048

  309. </p></dd>

  310. <dt>&lsquo;<samp>wquxga</samp>&rsquo;</dt>

  311. <dd><p>3840x2400

  312. </p></dd>

  313. <dt>&lsquo;<samp>whsxga</samp>&rsquo;</dt>

  314. <dd><p>6400x4096

  315. </p></dd>

  316. <dt>&lsquo;<samp>whuxga</samp>&rsquo;</dt>

  317. <dd><p>7680x4800

  318. </p></dd>

  319. <dt>&lsquo;<samp>cga</samp>&rsquo;</dt>

  320. <dd><p>320x200

  321. </p></dd>

  322. <dt>&lsquo;<samp>ega</samp>&rsquo;</dt>

  323. <dd><p>640x350

  324. </p></dd>

  325. <dt>&lsquo;<samp>hd480</samp>&rsquo;</dt>

  326. <dd><p>852x480

  327. </p></dd>

  328. <dt>&lsquo;<samp>hd720</samp>&rsquo;</dt>

  329. <dd><p>1280x720

  330. </p></dd>

  331. <dt>&lsquo;<samp>hd1080</samp>&rsquo;</dt>

  332. <dd><p>1920x1080

  333. </p></dd>

  334. <dt>&lsquo;<samp>2k</samp>&rsquo;</dt>

  335. <dd><p>2048x1080

  336. </p></dd>

  337. <dt>&lsquo;<samp>2kflat</samp>&rsquo;</dt>

  338. <dd><p>1998x1080

  339. </p></dd>

  340. <dt>&lsquo;<samp>2kscope</samp>&rsquo;</dt>

  341. <dd><p>2048x858

  342. </p></dd>

  343. <dt>&lsquo;<samp>4k</samp>&rsquo;</dt>

  344. <dd><p>4096x2160

  345. </p></dd>

  346. <dt>&lsquo;<samp>4kflat</samp>&rsquo;</dt>

  347. <dd><p>3996x2160

  348. </p></dd>

  349. <dt>&lsquo;<samp>4kscope</samp>&rsquo;</dt>

  350. <dd><p>4096x1716

  351. </p></dd>

  352. <dt>&lsquo;<samp>nhd</samp>&rsquo;</dt>

  353. <dd><p>640x360

  354. </p></dd>

  355. <dt>&lsquo;<samp>hqvga</samp>&rsquo;</dt>

  356. <dd><p>240x160

  357. </p></dd>

  358. <dt>&lsquo;<samp>wqvga</samp>&rsquo;</dt>

  359. <dd><p>400x240

  360. </p></dd>

  361. <dt>&lsquo;<samp>fwqvga</samp>&rsquo;</dt>

  362. <dd><p>432x240

  363. </p></dd>

  364. <dt>&lsquo;<samp>hvga</samp>&rsquo;</dt>

  365. <dd><p>480x320

  366. </p></dd>

  367. <dt>&lsquo;<samp>qhd</samp>&rsquo;</dt>

  368. <dd><p>960x540

  369. </p></dd>

  370. <dt>&lsquo;<samp>2kdci</samp>&rsquo;</dt>

  371. <dd><p>2048x1080

  372. </p></dd>

  373. <dt>&lsquo;<samp>4kdci</samp>&rsquo;</dt>

  374. <dd><p>4096x2160

  375. </p></dd>

  376. <dt>&lsquo;<samp>uhd2160</samp>&rsquo;</dt>

  377. <dd><p>3840x2160

  378. </p></dd>

  379. <dt>&lsquo;<samp>uhd4320</samp>&rsquo;</dt>

  380. <dd><p>7680x4320

  381. </p></dd>

  382. </dl>

  383. 

  384. <p><a name="video-rate-syntax"></a>

  385. </p><a name="Video-rate"></a>

  386. <h2 class="section"><a href="ffmpeg-utils.html#toc-Video-rate">2.5 Video rate</a></h2>

  387. 

  388. <p>Specify the frame rate of a video, expressed as the number of frames

  389. generated per second. It has to be a string in the format

  390. <var>frame_rate_num</var>/<var>frame_rate_den</var>, an integer number, a float

  391. number or a valid video frame rate abbreviation.

  392. </p>

  393. <p>The following abbreviations are recognized:

  394. </p><dl compact="compact">

  395. <dt>&lsquo;<samp>ntsc</samp>&rsquo;</dt>

  396. <dd><p>30000/1001

  397. </p></dd>

  398. <dt>&lsquo;<samp>pal</samp>&rsquo;</dt>

  399. <dd><p>25/1

  400. </p></dd>

  401. <dt>&lsquo;<samp>qntsc</samp>&rsquo;</dt>

  402. <dd><p>30000/1001

  403. </p></dd>

  404. <dt>&lsquo;<samp>qpal</samp>&rsquo;</dt>

  405. <dd><p>25/1

  406. </p></dd>

  407. <dt>&lsquo;<samp>sntsc</samp>&rsquo;</dt>

  408. <dd><p>30000/1001

  409. </p></dd>

  410. <dt>&lsquo;<samp>spal</samp>&rsquo;</dt>

  411. <dd><p>25/1

  412. </p></dd>

  413. <dt>&lsquo;<samp>film</samp>&rsquo;</dt>

  414. <dd><p>24/1

  415. </p></dd>

  416. <dt>&lsquo;<samp>ntsc-film</samp>&rsquo;</dt>

  417. <dd><p>24000/1001

  418. </p></dd>

  419. </dl>

  420. 

  421. <p><a name="ratio-syntax"></a>

  422. </p><a name="Ratio"></a>

  423. <h2 class="section"><a href="ffmpeg-utils.html#toc-Ratio">2.6 Ratio</a></h2>

  424. 

  425. <p>A ratio can be expressed as an expression, or in the form

  426. <var>numerator</var>:<var>denominator</var>.

  427. </p>

  428. <p>Note that a ratio with infinite (1/0) or negative value is

  429. considered valid, so you should check on the returned value if you

  430. want to exclude those values.

  431. </p>

  432. <p>The undefined value can be expressed using the &quot;0:0&quot; string.

  433. </p>

  434. <p><a name="color-syntax"></a>

  435. </p><a name="Color"></a>

  436. <h2 class="section"><a href="ffmpeg-utils.html#toc-Color">2.7 Color</a></h2>

  437. 

  438. <p>It can be the name of a color as defined below (case insensitive match) or a

  439. <code>[0x|#]RRGGBB[AA]</code> sequence, possibly followed by @ and a string

  440. representing the alpha component.

  441. </p>

  442. <p>The alpha component may be a string composed by &quot;0x&quot; followed by an

  443. hexadecimal number or a decimal number between 0.0 and 1.0, which

  444. represents the opacity value (&lsquo;<samp>0x00</samp>&rsquo; or &lsquo;<samp>0.0</samp>&rsquo; means completely

  445. transparent, &lsquo;<samp>0xff</samp>&rsquo; or &lsquo;<samp>1.0</samp>&rsquo; completely opaque). If the alpha

  446. component is not specified then &lsquo;<samp>0xff</samp>&rsquo; is assumed.

  447. </p>

  448. <p>The string &lsquo;<samp>random</samp>&rsquo; will result in a random color.

  449. </p>

  450. <p>The following names of colors are recognized:

  451. </p><dl compact="compact">

  452. <dt>&lsquo;<samp>AliceBlue</samp>&rsquo;</dt>

  453. <dd><p>0xF0F8FF

  454. </p></dd>

  455. <dt>&lsquo;<samp>AntiqueWhite</samp>&rsquo;</dt>

  456. <dd><p>0xFAEBD7

  457. </p></dd>

  458. <dt>&lsquo;<samp>Aqua</samp>&rsquo;</dt>

  459. <dd><p>0x00FFFF

  460. </p></dd>

  461. <dt>&lsquo;<samp>Aquamarine</samp>&rsquo;</dt>

  462. <dd><p>0x7FFFD4

  463. </p></dd>

  464. <dt>&lsquo;<samp>Azure</samp>&rsquo;</dt>

  465. <dd><p>0xF0FFFF

  466. </p></dd>

  467. <dt>&lsquo;<samp>Beige</samp>&rsquo;</dt>

  468. <dd><p>0xF5F5DC

  469. </p></dd>

  470. <dt>&lsquo;<samp>Bisque</samp>&rsquo;</dt>

  471. <dd><p>0xFFE4C4

  472. </p></dd>

  473. <dt>&lsquo;<samp>Black</samp>&rsquo;</dt>

  474. <dd><p>0x000000

  475. </p></dd>

  476. <dt>&lsquo;<samp>BlanchedAlmond</samp>&rsquo;</dt>

  477. <dd><p>0xFFEBCD

  478. </p></dd>

  479. <dt>&lsquo;<samp>Blue</samp>&rsquo;</dt>

  480. <dd><p>0x0000FF

  481. </p></dd>

  482. <dt>&lsquo;<samp>BlueViolet</samp>&rsquo;</dt>

  483. <dd><p>0x8A2BE2

  484. </p></dd>

  485. <dt>&lsquo;<samp>Brown</samp>&rsquo;</dt>

  486. <dd><p>0xA52A2A

  487. </p></dd>

  488. <dt>&lsquo;<samp>BurlyWood</samp>&rsquo;</dt>

  489. <dd><p>0xDEB887

  490. </p></dd>

  491. <dt>&lsquo;<samp>CadetBlue</samp>&rsquo;</dt>

  492. <dd><p>0x5F9EA0

  493. </p></dd>

  494. <dt>&lsquo;<samp>Chartreuse</samp>&rsquo;</dt>

  495. <dd><p>0x7FFF00

  496. </p></dd>

  497. <dt>&lsquo;<samp>Chocolate</samp>&rsquo;</dt>

  498. <dd><p>0xD2691E

  499. </p></dd>

  500. <dt>&lsquo;<samp>Coral</samp>&rsquo;</dt>

  501. <dd><p>0xFF7F50

  502. </p></dd>

  503. <dt>&lsquo;<samp>CornflowerBlue</samp>&rsquo;</dt>

  504. <dd><p>0x6495ED

  505. </p></dd>

  506. <dt>&lsquo;<samp>Cornsilk</samp>&rsquo;</dt>

  507. <dd><p>0xFFF8DC

  508. </p></dd>

  509. <dt>&lsquo;<samp>Crimson</samp>&rsquo;</dt>

  510. <dd><p>0xDC143C

  511. </p></dd>

  512. <dt>&lsquo;<samp>Cyan</samp>&rsquo;</dt>

  513. <dd><p>0x00FFFF

  514. </p></dd>

  515. <dt>&lsquo;<samp>DarkBlue</samp>&rsquo;</dt>

  516. <dd><p>0x00008B

  517. </p></dd>

  518. <dt>&lsquo;<samp>DarkCyan</samp>&rsquo;</dt>

  519. <dd><p>0x008B8B

  520. </p></dd>

  521. <dt>&lsquo;<samp>DarkGoldenRod</samp>&rsquo;</dt>

  522. <dd><p>0xB8860B

  523. </p></dd>

  524. <dt>&lsquo;<samp>DarkGray</samp>&rsquo;</dt>

  525. <dd><p>0xA9A9A9

  526. </p></dd>

  527. <dt>&lsquo;<samp>DarkGreen</samp>&rsquo;</dt>

  528. <dd><p>0x006400

  529. </p></dd>

  530. <dt>&lsquo;<samp>DarkKhaki</samp>&rsquo;</dt>

  531. <dd><p>0xBDB76B

  532. </p></dd>

  533. <dt>&lsquo;<samp>DarkMagenta</samp>&rsquo;</dt>

  534. <dd><p>0x8B008B

  535. </p></dd>

  536. <dt>&lsquo;<samp>DarkOliveGreen</samp>&rsquo;</dt>

  537. <dd><p>0x556B2F

  538. </p></dd>

  539. <dt>&lsquo;<samp>Darkorange</samp>&rsquo;</dt>

  540. <dd><p>0xFF8C00

  541. </p></dd>

  542. <dt>&lsquo;<samp>DarkOrchid</samp>&rsquo;</dt>

  543. <dd><p>0x9932CC

  544. </p></dd>

  545. <dt>&lsquo;<samp>DarkRed</samp>&rsquo;</dt>

  546. <dd><p>0x8B0000

  547. </p></dd>

  548. <dt>&lsquo;<samp>DarkSalmon</samp>&rsquo;</dt>

  549. <dd><p>0xE9967A

  550. </p></dd>

  551. <dt>&lsquo;<samp>DarkSeaGreen</samp>&rsquo;</dt>

  552. <dd><p>0x8FBC8F

  553. </p></dd>

  554. <dt>&lsquo;<samp>DarkSlateBlue</samp>&rsquo;</dt>

  555. <dd><p>0x483D8B

  556. </p></dd>

  557. <dt>&lsquo;<samp>DarkSlateGray</samp>&rsquo;</dt>

  558. <dd><p>0x2F4F4F

  559. </p></dd>

  560. <dt>&lsquo;<samp>DarkTurquoise</samp>&rsquo;</dt>

  561. <dd><p>0x00CED1

  562. </p></dd>

  563. <dt>&lsquo;<samp>DarkViolet</samp>&rsquo;</dt>

  564. <dd><p>0x9400D3

  565. </p></dd>

  566. <dt>&lsquo;<samp>DeepPink</samp>&rsquo;</dt>

  567. <dd><p>0xFF1493

  568. </p></dd>

  569. <dt>&lsquo;<samp>DeepSkyBlue</samp>&rsquo;</dt>

  570. <dd><p>0x00BFFF

  571. </p></dd>

  572. <dt>&lsquo;<samp>DimGray</samp>&rsquo;</dt>

  573. <dd><p>0x696969

  574. </p></dd>

  575. <dt>&lsquo;<samp>DodgerBlue</samp>&rsquo;</dt>

  576. <dd><p>0x1E90FF

  577. </p></dd>

  578. <dt>&lsquo;<samp>FireBrick</samp>&rsquo;</dt>

  579. <dd><p>0xB22222

  580. </p></dd>

  581. <dt>&lsquo;<samp>FloralWhite</samp>&rsquo;</dt>

  582. <dd><p>0xFFFAF0

  583. </p></dd>

  584. <dt>&lsquo;<samp>ForestGreen</samp>&rsquo;</dt>

  585. <dd><p>0x228B22

  586. </p></dd>

  587. <dt>&lsquo;<samp>Fuchsia</samp>&rsquo;</dt>

  588. <dd><p>0xFF00FF

  589. </p></dd>

  590. <dt>&lsquo;<samp>Gainsboro</samp>&rsquo;</dt>

  591. <dd><p>0xDCDCDC

  592. </p></dd>

  593. <dt>&lsquo;<samp>GhostWhite</samp>&rsquo;</dt>

  594. <dd><p>0xF8F8FF

  595. </p></dd>

  596. <dt>&lsquo;<samp>Gold</samp>&rsquo;</dt>

  597. <dd><p>0xFFD700

  598. </p></dd>

  599. <dt>&lsquo;<samp>GoldenRod</samp>&rsquo;</dt>

  600. <dd><p>0xDAA520

  601. </p></dd>

  602. <dt>&lsquo;<samp>Gray</samp>&rsquo;</dt>

  603. <dd><p>0x808080

  604. </p></dd>

  605. <dt>&lsquo;<samp>Green</samp>&rsquo;</dt>

  606. <dd><p>0x008000

  607. </p></dd>

  608. <dt>&lsquo;<samp>GreenYellow</samp>&rsquo;</dt>

  609. <dd><p>0xADFF2F

  610. </p></dd>

  611. <dt>&lsquo;<samp>HoneyDew</samp>&rsquo;</dt>

  612. <dd><p>0xF0FFF0

  613. </p></dd>

  614. <dt>&lsquo;<samp>HotPink</samp>&rsquo;</dt>

  615. <dd><p>0xFF69B4

  616. </p></dd>

  617. <dt>&lsquo;<samp>IndianRed</samp>&rsquo;</dt>

  618. <dd><p>0xCD5C5C

  619. </p></dd>

  620. <dt>&lsquo;<samp>Indigo</samp>&rsquo;</dt>

  621. <dd><p>0x4B0082

  622. </p></dd>

  623. <dt>&lsquo;<samp>Ivory</samp>&rsquo;</dt>

  624. <dd><p>0xFFFFF0

  625. </p></dd>

  626. <dt>&lsquo;<samp>Khaki</samp>&rsquo;</dt>

  627. <dd><p>0xF0E68C

  628. </p></dd>

  629. <dt>&lsquo;<samp>Lavender</samp>&rsquo;</dt>

  630. <dd><p>0xE6E6FA

  631. </p></dd>

  632. <dt>&lsquo;<samp>LavenderBlush</samp>&rsquo;</dt>

  633. <dd><p>0xFFF0F5

  634. </p></dd>

  635. <dt>&lsquo;<samp>LawnGreen</samp>&rsquo;</dt>

  636. <dd><p>0x7CFC00

  637. </p></dd>

  638. <dt>&lsquo;<samp>LemonChiffon</samp>&rsquo;</dt>

  639. <dd><p>0xFFFACD

  640. </p></dd>

  641. <dt>&lsquo;<samp>LightBlue</samp>&rsquo;</dt>

  642. <dd><p>0xADD8E6

  643. </p></dd>

  644. <dt>&lsquo;<samp>LightCoral</samp>&rsquo;</dt>

  645. <dd><p>0xF08080

  646. </p></dd>

  647. <dt>&lsquo;<samp>LightCyan</samp>&rsquo;</dt>

  648. <dd><p>0xE0FFFF

  649. </p></dd>

  650. <dt>&lsquo;<samp>LightGoldenRodYellow</samp>&rsquo;</dt>

  651. <dd><p>0xFAFAD2

  652. </p></dd>

  653. <dt>&lsquo;<samp>LightGreen</samp>&rsquo;</dt>

  654. <dd><p>0x90EE90

  655. </p></dd>

  656. <dt>&lsquo;<samp>LightGrey</samp>&rsquo;</dt>

  657. <dd><p>0xD3D3D3

  658. </p></dd>

  659. <dt>&lsquo;<samp>LightPink</samp>&rsquo;</dt>

  660. <dd><p>0xFFB6C1

  661. </p></dd>

  662. <dt>&lsquo;<samp>LightSalmon</samp>&rsquo;</dt>

  663. <dd><p>0xFFA07A

  664. </p></dd>

  665. <dt>&lsquo;<samp>LightSeaGreen</samp>&rsquo;</dt>

  666. <dd><p>0x20B2AA

  667. </p></dd>

  668. <dt>&lsquo;<samp>LightSkyBlue</samp>&rsquo;</dt>

  669. <dd><p>0x87CEFA

  670. </p></dd>

  671. <dt>&lsquo;<samp>LightSlateGray</samp>&rsquo;</dt>

  672. <dd><p>0x778899

  673. </p></dd>

  674. <dt>&lsquo;<samp>LightSteelBlue</samp>&rsquo;</dt>

  675. <dd><p>0xB0C4DE

  676. </p></dd>

  677. <dt>&lsquo;<samp>LightYellow</samp>&rsquo;</dt>

  678. <dd><p>0xFFFFE0

  679. </p></dd>

  680. <dt>&lsquo;<samp>Lime</samp>&rsquo;</dt>

  681. <dd><p>0x00FF00

  682. </p></dd>

  683. <dt>&lsquo;<samp>LimeGreen</samp>&rsquo;</dt>

  684. <dd><p>0x32CD32

  685. </p></dd>

  686. <dt>&lsquo;<samp>Linen</samp>&rsquo;</dt>

  687. <dd><p>0xFAF0E6

  688. </p></dd>

  689. <dt>&lsquo;<samp>Magenta</samp>&rsquo;</dt>

  690. <dd><p>0xFF00FF

  691. </p></dd>

  692. <dt>&lsquo;<samp>Maroon</samp>&rsquo;</dt>

  693. <dd><p>0x800000

  694. </p></dd>

  695. <dt>&lsquo;<samp>MediumAquaMarine</samp>&rsquo;</dt>

  696. <dd><p>0x66CDAA

  697. </p></dd>

  698. <dt>&lsquo;<samp>MediumBlue</samp>&rsquo;</dt>

  699. <dd><p>0x0000CD

  700. </p></dd>

  701. <dt>&lsquo;<samp>MediumOrchid</samp>&rsquo;</dt>

  702. <dd><p>0xBA55D3

  703. </p></dd>

  704. <dt>&lsquo;<samp>MediumPurple</samp>&rsquo;</dt>

  705. <dd><p>0x9370D8

  706. </p></dd>

  707. <dt>&lsquo;<samp>MediumSeaGreen</samp>&rsquo;</dt>

  708. <dd><p>0x3CB371

  709. </p></dd>

  710. <dt>&lsquo;<samp>MediumSlateBlue</samp>&rsquo;</dt>

  711. <dd><p>0x7B68EE

  712. </p></dd>

  713. <dt>&lsquo;<samp>MediumSpringGreen</samp>&rsquo;</dt>

  714. <dd><p>0x00FA9A

  715. </p></dd>

  716. <dt>&lsquo;<samp>MediumTurquoise</samp>&rsquo;</dt>

  717. <dd><p>0x48D1CC

  718. </p></dd>

  719. <dt>&lsquo;<samp>MediumVioletRed</samp>&rsquo;</dt>

  720. <dd><p>0xC71585

  721. </p></dd>

  722. <dt>&lsquo;<samp>MidnightBlue</samp>&rsquo;</dt>

  723. <dd><p>0x191970

  724. </p></dd>

  725. <dt>&lsquo;<samp>MintCream</samp>&rsquo;</dt>

  726. <dd><p>0xF5FFFA

  727. </p></dd>

  728. <dt>&lsquo;<samp>MistyRose</samp>&rsquo;</dt>

  729. <dd><p>0xFFE4E1

  730. </p></dd>

  731. <dt>&lsquo;<samp>Moccasin</samp>&rsquo;</dt>

  732. <dd><p>0xFFE4B5

  733. </p></dd>

  734. <dt>&lsquo;<samp>NavajoWhite</samp>&rsquo;</dt>

  735. <dd><p>0xFFDEAD

  736. </p></dd>

  737. <dt>&lsquo;<samp>Navy</samp>&rsquo;</dt>

  738. <dd><p>0x000080

  739. </p></dd>

  740. <dt>&lsquo;<samp>OldLace</samp>&rsquo;</dt>

  741. <dd><p>0xFDF5E6

  742. </p></dd>

  743. <dt>&lsquo;<samp>Olive</samp>&rsquo;</dt>

  744. <dd><p>0x808000

  745. </p></dd>

  746. <dt>&lsquo;<samp>OliveDrab</samp>&rsquo;</dt>

  747. <dd><p>0x6B8E23

  748. </p></dd>

  749. <dt>&lsquo;<samp>Orange</samp>&rsquo;</dt>

  750. <dd><p>0xFFA500

  751. </p></dd>

  752. <dt>&lsquo;<samp>OrangeRed</samp>&rsquo;</dt>

  753. <dd><p>0xFF4500

  754. </p></dd>

  755. <dt>&lsquo;<samp>Orchid</samp>&rsquo;</dt>

  756. <dd><p>0xDA70D6

  757. </p></dd>

  758. <dt>&lsquo;<samp>PaleGoldenRod</samp>&rsquo;</dt>

  759. <dd><p>0xEEE8AA

  760. </p></dd>

  761. <dt>&lsquo;<samp>PaleGreen</samp>&rsquo;</dt>

  762. <dd><p>0x98FB98

  763. </p></dd>

  764. <dt>&lsquo;<samp>PaleTurquoise</samp>&rsquo;</dt>

  765. <dd><p>0xAFEEEE

  766. </p></dd>

  767. <dt>&lsquo;<samp>PaleVioletRed</samp>&rsquo;</dt>

  768. <dd><p>0xD87093

  769. </p></dd>

  770. <dt>&lsquo;<samp>PapayaWhip</samp>&rsquo;</dt>

  771. <dd><p>0xFFEFD5

  772. </p></dd>

  773. <dt>&lsquo;<samp>PeachPuff</samp>&rsquo;</dt>

  774. <dd><p>0xFFDAB9

  775. </p></dd>

  776. <dt>&lsquo;<samp>Peru</samp>&rsquo;</dt>

  777. <dd><p>0xCD853F

  778. </p></dd>

  779. <dt>&lsquo;<samp>Pink</samp>&rsquo;</dt>

  780. <dd><p>0xFFC0CB

  781. </p></dd>

  782. <dt>&lsquo;<samp>Plum</samp>&rsquo;</dt>

  783. <dd><p>0xDDA0DD

  784. </p></dd>

  785. <dt>&lsquo;<samp>PowderBlue</samp>&rsquo;</dt>

  786. <dd><p>0xB0E0E6

  787. </p></dd>

  788. <dt>&lsquo;<samp>Purple</samp>&rsquo;</dt>

  789. <dd><p>0x800080

  790. </p></dd>

  791. <dt>&lsquo;<samp>Red</samp>&rsquo;</dt>

  792. <dd><p>0xFF0000

  793. </p></dd>

  794. <dt>&lsquo;<samp>RosyBrown</samp>&rsquo;</dt>

  795. <dd><p>0xBC8F8F

  796. </p></dd>

  797. <dt>&lsquo;<samp>RoyalBlue</samp>&rsquo;</dt>

  798. <dd><p>0x4169E1

  799. </p></dd>

  800. <dt>&lsquo;<samp>SaddleBrown</samp>&rsquo;</dt>

  801. <dd><p>0x8B4513

  802. </p></dd>

  803. <dt>&lsquo;<samp>Salmon</samp>&rsquo;</dt>

  804. <dd><p>0xFA8072

  805. </p></dd>

  806. <dt>&lsquo;<samp>SandyBrown</samp>&rsquo;</dt>

  807. <dd><p>0xF4A460

  808. </p></dd>

  809. <dt>&lsquo;<samp>SeaGreen</samp>&rsquo;</dt>

  810. <dd><p>0x2E8B57

  811. </p></dd>

  812. <dt>&lsquo;<samp>SeaShell</samp>&rsquo;</dt>

  813. <dd><p>0xFFF5EE

  814. </p></dd>

  815. <dt>&lsquo;<samp>Sienna</samp>&rsquo;</dt>

  816. <dd><p>0xA0522D

  817. </p></dd>

  818. <dt>&lsquo;<samp>Silver</samp>&rsquo;</dt>

  819. <dd><p>0xC0C0C0

  820. </p></dd>

  821. <dt>&lsquo;<samp>SkyBlue</samp>&rsquo;</dt>

  822. <dd><p>0x87CEEB

  823. </p></dd>

  824. <dt>&lsquo;<samp>SlateBlue</samp>&rsquo;</dt>

  825. <dd><p>0x6A5ACD

  826. </p></dd>

  827. <dt>&lsquo;<samp>SlateGray</samp>&rsquo;</dt>

  828. <dd><p>0x708090

  829. </p></dd>

  830. <dt>&lsquo;<samp>Snow</samp>&rsquo;</dt>

  831. <dd><p>0xFFFAFA

  832. </p></dd>

  833. <dt>&lsquo;<samp>SpringGreen</samp>&rsquo;</dt>

  834. <dd><p>0x00FF7F

  835. </p></dd>

  836. <dt>&lsquo;<samp>SteelBlue</samp>&rsquo;</dt>

  837. <dd><p>0x4682B4

  838. </p></dd>

  839. <dt>&lsquo;<samp>Tan</samp>&rsquo;</dt>

  840. <dd><p>0xD2B48C

  841. </p></dd>

  842. <dt>&lsquo;<samp>Teal</samp>&rsquo;</dt>

  843. <dd><p>0x008080

  844. </p></dd>

  845. <dt>&lsquo;<samp>Thistle</samp>&rsquo;</dt>

  846. <dd><p>0xD8BFD8

  847. </p></dd>

  848. <dt>&lsquo;<samp>Tomato</samp>&rsquo;</dt>

  849. <dd><p>0xFF6347

  850. </p></dd>

  851. <dt>&lsquo;<samp>Turquoise</samp>&rsquo;</dt>

  852. <dd><p>0x40E0D0

  853. </p></dd>

  854. <dt>&lsquo;<samp>Violet</samp>&rsquo;</dt>

  855. <dd><p>0xEE82EE

  856. </p></dd>

  857. <dt>&lsquo;<samp>Wheat</samp>&rsquo;</dt>

  858. <dd><p>0xF5DEB3

  859. </p></dd>

  860. <dt>&lsquo;<samp>White</samp>&rsquo;</dt>

  861. <dd><p>0xFFFFFF

  862. </p></dd>

  863. <dt>&lsquo;<samp>WhiteSmoke</samp>&rsquo;</dt>

  864. <dd><p>0xF5F5F5

  865. </p></dd>

  866. <dt>&lsquo;<samp>Yellow</samp>&rsquo;</dt>

  867. <dd><p>0xFFFF00

  868. </p></dd>

  869. <dt>&lsquo;<samp>YellowGreen</samp>&rsquo;</dt>

  870. <dd><p>0x9ACD32

  871. </p></dd>

  872. </dl>

  873. 

  874. <p><a name="channel-layout-syntax"></a>

  875. </p><a name="Channel-Layout"></a>

  876. <h2 class="section"><a href="ffmpeg-utils.html#toc-Channel-Layout">2.8 Channel Layout</a></h2>

  877. 

  878. <p>A channel layout specifies the spatial disposition of the channels in

  879. a multi-channel audio stream. To specify a channel layout, FFmpeg

  880. makes use of a special syntax.

  881. </p>

  882. <p>Individual channels are identified by an id, as given by the table

  883. below:

  884. </p><dl compact="compact">

  885. <dt>&lsquo;<samp>FL</samp>&rsquo;</dt>

  886. <dd><p>front left

  887. </p></dd>

  888. <dt>&lsquo;<samp>FR</samp>&rsquo;</dt>

  889. <dd><p>front right

  890. </p></dd>

  891. <dt>&lsquo;<samp>FC</samp>&rsquo;</dt>

  892. <dd><p>front center

  893. </p></dd>

  894. <dt>&lsquo;<samp>LFE</samp>&rsquo;</dt>

  895. <dd><p>low frequency

  896. </p></dd>

  897. <dt>&lsquo;<samp>BL</samp>&rsquo;</dt>

  898. <dd><p>back left

  899. </p></dd>

  900. <dt>&lsquo;<samp>BR</samp>&rsquo;</dt>

  901. <dd><p>back right

  902. </p></dd>

  903. <dt>&lsquo;<samp>FLC</samp>&rsquo;</dt>

  904. <dd><p>front left-of-center

  905. </p></dd>

  906. <dt>&lsquo;<samp>FRC</samp>&rsquo;</dt>

  907. <dd><p>front right-of-center

  908. </p></dd>

  909. <dt>&lsquo;<samp>BC</samp>&rsquo;</dt>

  910. <dd><p>back center

  911. </p></dd>

  912. <dt>&lsquo;<samp>SL</samp>&rsquo;</dt>

  913. <dd><p>side left

  914. </p></dd>

  915. <dt>&lsquo;<samp>SR</samp>&rsquo;</dt>

  916. <dd><p>side right

  917. </p></dd>

  918. <dt>&lsquo;<samp>TC</samp>&rsquo;</dt>

  919. <dd><p>top center

  920. </p></dd>

  921. <dt>&lsquo;<samp>TFL</samp>&rsquo;</dt>

  922. <dd><p>top front left

  923. </p></dd>

  924. <dt>&lsquo;<samp>TFC</samp>&rsquo;</dt>

  925. <dd><p>top front center

  926. </p></dd>

  927. <dt>&lsquo;<samp>TFR</samp>&rsquo;</dt>

  928. <dd><p>top front right

  929. </p></dd>

  930. <dt>&lsquo;<samp>TBL</samp>&rsquo;</dt>

  931. <dd><p>top back left

  932. </p></dd>

  933. <dt>&lsquo;<samp>TBC</samp>&rsquo;</dt>

  934. <dd><p>top back center

  935. </p></dd>

  936. <dt>&lsquo;<samp>TBR</samp>&rsquo;</dt>

  937. <dd><p>top back right

  938. </p></dd>

  939. <dt>&lsquo;<samp>DL</samp>&rsquo;</dt>

  940. <dd><p>downmix left

  941. </p></dd>

  942. <dt>&lsquo;<samp>DR</samp>&rsquo;</dt>

  943. <dd><p>downmix right

  944. </p></dd>

  945. <dt>&lsquo;<samp>WL</samp>&rsquo;</dt>

  946. <dd><p>wide left

  947. </p></dd>

  948. <dt>&lsquo;<samp>WR</samp>&rsquo;</dt>

  949. <dd><p>wide right

  950. </p></dd>

  951. <dt>&lsquo;<samp>SDL</samp>&rsquo;</dt>

  952. <dd><p>surround direct left

  953. </p></dd>

  954. <dt>&lsquo;<samp>SDR</samp>&rsquo;</dt>

  955. <dd><p>surround direct right

  956. </p></dd>

  957. <dt>&lsquo;<samp>LFE2</samp>&rsquo;</dt>

  958. <dd><p>low frequency 2

  959. </p></dd>

  960. </dl>

  961. 

  962. <p>Standard channel layout compositions can be specified by using the

  963. following identifiers:

  964. </p><dl compact="compact">

  965. <dt>&lsquo;<samp>mono</samp>&rsquo;</dt>

  966. <dd><p>FC

  967. </p></dd>

  968. <dt>&lsquo;<samp>stereo</samp>&rsquo;</dt>

  969. <dd><p>FL+FR

  970. </p></dd>

  971. <dt>&lsquo;<samp>2.1</samp>&rsquo;</dt>

  972. <dd><p>FL+FR+LFE

  973. </p></dd>

  974. <dt>&lsquo;<samp>3.0</samp>&rsquo;</dt>

  975. <dd><p>FL+FR+FC

  976. </p></dd>

  977. <dt>&lsquo;<samp>3.0(back)</samp>&rsquo;</dt>

  978. <dd><p>FL+FR+BC

  979. </p></dd>

  980. <dt>&lsquo;<samp>4.0</samp>&rsquo;</dt>

  981. <dd><p>FL+FR+FC+BC

  982. </p></dd>

  983. <dt>&lsquo;<samp>quad</samp>&rsquo;</dt>

  984. <dd><p>FL+FR+BL+BR

  985. </p></dd>

  986. <dt>&lsquo;<samp>quad(side)</samp>&rsquo;</dt>

  987. <dd><p>FL+FR+SL+SR

  988. </p></dd>

  989. <dt>&lsquo;<samp>3.1</samp>&rsquo;</dt>

  990. <dd><p>FL+FR+FC+LFE

  991. </p></dd>

  992. <dt>&lsquo;<samp>5.0</samp>&rsquo;</dt>

  993. <dd><p>FL+FR+FC+BL+BR

  994. </p></dd>

  995. <dt>&lsquo;<samp>5.0(side)</samp>&rsquo;</dt>

  996. <dd><p>FL+FR+FC+SL+SR

  997. </p></dd>

  998. <dt>&lsquo;<samp>4.1</samp>&rsquo;</dt>

  999. <dd><p>FL+FR+FC+LFE+BC

  1000. </p></dd>

  1001. <dt>&lsquo;<samp>5.1</samp>&rsquo;</dt>

  1002. <dd><p>FL+FR+FC+LFE+BL+BR

  1003. </p></dd>

  1004. <dt>&lsquo;<samp>5.1(side)</samp>&rsquo;</dt>

  1005. <dd><p>FL+FR+FC+LFE+SL+SR

  1006. </p></dd>

  1007. <dt>&lsquo;<samp>6.0</samp>&rsquo;</dt>

  1008. <dd><p>FL+FR+FC+BC+SL+SR

  1009. </p></dd>

  1010. <dt>&lsquo;<samp>6.0(front)</samp>&rsquo;</dt>

  1011. <dd><p>FL+FR+FLC+FRC+SL+SR

  1012. </p></dd>

  1013. <dt>&lsquo;<samp>hexagonal</samp>&rsquo;</dt>

  1014. <dd><p>FL+FR+FC+BL+BR+BC

  1015. </p></dd>

  1016. <dt>&lsquo;<samp>6.1</samp>&rsquo;</dt>

  1017. <dd><p>FL+FR+FC+LFE+BC+SL+SR

  1018. </p></dd>

  1019. <dt>&lsquo;<samp>6.1</samp>&rsquo;</dt>

  1020. <dd><p>FL+FR+FC+LFE+BL+BR+BC

  1021. </p></dd>

  1022. <dt>&lsquo;<samp>6.1(front)</samp>&rsquo;</dt>

  1023. <dd><p>FL+FR+LFE+FLC+FRC+SL+SR

  1024. </p></dd>

  1025. <dt>&lsquo;<samp>7.0</samp>&rsquo;</dt>

  1026. <dd><p>FL+FR+FC+BL+BR+SL+SR

  1027. </p></dd>

  1028. <dt>&lsquo;<samp>7.0(front)</samp>&rsquo;</dt>

  1029. <dd><p>FL+FR+FC+FLC+FRC+SL+SR

  1030. </p></dd>

  1031. <dt>&lsquo;<samp>7.1</samp>&rsquo;</dt>

  1032. <dd><p>FL+FR+FC+LFE+BL+BR+SL+SR

  1033. </p></dd>

  1034. <dt>&lsquo;<samp>7.1(wide)</samp>&rsquo;</dt>

  1035. <dd><p>FL+FR+FC+LFE+BL+BR+FLC+FRC

  1036. </p></dd>

  1037. <dt>&lsquo;<samp>7.1(wide-side)</samp>&rsquo;</dt>

  1038. <dd><p>FL+FR+FC+LFE+FLC+FRC+SL+SR

  1039. </p></dd>

  1040. <dt>&lsquo;<samp>octagonal</samp>&rsquo;</dt>

  1041. <dd><p>FL+FR+FC+BL+BR+BC+SL+SR

  1042. </p></dd>

  1043. <dt>&lsquo;<samp>hexadecagonal</samp>&rsquo;</dt>

  1044. <dd><p>FL+FR+FC+BL+BR+BC+SL+SR+WL+WR+TBL+TBR+TBC+TFC+TFL+TFR

  1045. </p></dd>

  1046. <dt>&lsquo;<samp>downmix</samp>&rsquo;</dt>

  1047. <dd><p>DL+DR

  1048. </p></dd>

  1049. </dl>

  1050. 

  1051. <p>A custom channel layout can be specified as a sequence of terms, separated by

  1052. &rsquo;+&rsquo; or &rsquo;|&rsquo;. Each term can be:

  1053. </p><ul>

  1054. <li>

  1055. the name of a standard channel layout (e.g. &lsquo;<samp>mono</samp>&rsquo;,

  1056. &lsquo;<samp>stereo</samp>&rsquo;, &lsquo;<samp>4.0</samp>&rsquo;, &lsquo;<samp>quad</samp>&rsquo;, &lsquo;<samp>5.0</samp>&rsquo;, etc.)

  1057. 

  1058. </li><li>

  1059. the name of a single channel (e.g. &lsquo;<samp>FL</samp>&rsquo;, &lsquo;<samp>FR</samp>&rsquo;, &lsquo;<samp>FC</samp>&rsquo;, &lsquo;<samp>LFE</samp>&rsquo;, etc.)

  1060. 

  1061. </li><li>

  1062. a number of channels, in decimal, followed by &rsquo;c&rsquo;, yielding the default channel

  1063. layout for that number of channels (see the function

  1064. <code>av_get_default_channel_layout</code>). Note that not all channel counts have a

  1065. default layout.

  1066. 

  1067. </li><li>

  1068. a number of channels, in decimal, followed by &rsquo;C&rsquo;, yielding an unknown channel

  1069. layout with the specified number of channels. Note that not all channel layout

  1070. specification strings support unknown channel layouts.

  1071. 

  1072. </li><li>

  1073. a channel layout mask, in hexadecimal starting with &quot;0x&quot; (see the

  1074. <code>AV_CH_*</code> macros in &lsquo;<tt>libavutil/channel_layout.h</tt>&rsquo;.

  1075. </li></ul>

  1076. 

  1077. <p>Before libavutil version 53 the trailing character &quot;c&quot; to specify a number of

  1078. channels was optional, but now it is required, while a channel layout mask can

  1079. also be specified as a decimal number (if and only if not followed by &quot;c&quot; or &quot;C&quot;).

  1080. </p>

  1081. <p>See also the function <code>av_get_channel_layout</code> defined in

  1082. &lsquo;<tt>libavutil/channel_layout.h</tt>&rsquo;.

  1083. </p>

  1084. <a name="Expression-Evaluation"></a>

  1085. <h1 class="chapter"><a href="ffmpeg-utils.html#toc-Expression-Evaluation">3 Expression Evaluation</a></h1>

  1086. 

  1087. <p>When evaluating an arithmetic expression, FFmpeg uses an internal

  1088. formula evaluator, implemented through the &lsquo;<tt>libavutil/eval.h</tt>&rsquo;

  1089. interface.

  1090. </p>

  1091. <p>An expression may contain unary, binary operators, constants, and

  1092. functions.

  1093. </p>

  1094. <p>Two expressions <var>expr1</var> and <var>expr2</var> can be combined to form

  1095. another expression &quot;<var>expr1</var>;<var>expr2</var>&quot;.

  1096. <var>expr1</var> and <var>expr2</var> are evaluated in turn, and the new

  1097. expression evaluates to the value of <var>expr2</var>.

  1098. </p>

  1099. <p>The following binary operators are available: <code>+</code>, <code>-</code>,

  1100. <code>*</code>, <code>/</code>, <code>^</code>.

  1101. </p>

  1102. <p>The following unary operators are available: <code>+</code>, <code>-</code>.

  1103. </p>

  1104. <p>The following functions are available:

  1105. </p><dl compact="compact">

  1106. <dt>&lsquo;<samp>abs(x)</samp>&rsquo;</dt>

  1107. <dd><p>Compute absolute value of <var>x</var>.

  1108. </p>

  1109. </dd>

  1110. <dt>&lsquo;<samp>acos(x)</samp>&rsquo;</dt>

  1111. <dd><p>Compute arccosine of <var>x</var>.

  1112. </p>

  1113. </dd>

  1114. <dt>&lsquo;<samp>asin(x)</samp>&rsquo;</dt>

  1115. <dd><p>Compute arcsine of <var>x</var>.

  1116. </p>

  1117. </dd>

  1118. <dt>&lsquo;<samp>atan(x)</samp>&rsquo;</dt>

  1119. <dd><p>Compute arctangent of <var>x</var>.

  1120. </p>

  1121. </dd>

  1122. <dt>&lsquo;<samp>atan2(x, y)</samp>&rsquo;</dt>

  1123. <dd><p>Compute principal value of the arc tangent of <var>y</var>/<var>x</var>.

  1124. </p>

  1125. </dd>

  1126. <dt>&lsquo;<samp>between(x, min, max)</samp>&rsquo;</dt>

  1127. <dd><p>Return 1 if <var>x</var> is greater than or equal to <var>min</var> and lesser than or

  1128. equal to <var>max</var>, 0 otherwise.

  1129. </p>

  1130. </dd>

  1131. <dt>&lsquo;<samp>bitand(x, y)</samp>&rsquo;</dt>

  1132. <dt>&lsquo;<samp>bitor(x, y)</samp>&rsquo;</dt>

  1133. <dd><p>Compute bitwise and/or operation on <var>x</var> and <var>y</var>.

  1134. </p>

  1135. <p>The results of the evaluation of <var>x</var> and <var>y</var> are converted to

  1136. integers before executing the bitwise operation.

  1137. </p>

  1138. <p>Note that both the conversion to integer and the conversion back to

  1139. floating point can lose precision. Beware of unexpected results for

  1140. large numbers (usually 2^53 and larger).

  1141. </p>

  1142. </dd>

  1143. <dt>&lsquo;<samp>ceil(expr)</samp>&rsquo;</dt>

  1144. <dd><p>Round the value of expression <var>expr</var> upwards to the nearest

  1145. integer. For example, &quot;ceil(1.5)&quot; is &quot;2.0&quot;.

  1146. </p>

  1147. </dd>

  1148. <dt>&lsquo;<samp>clip(x, min, max)</samp>&rsquo;</dt>

  1149. <dd><p>Return the value of <var>x</var> clipped between <var>min</var> and <var>max</var>.

  1150. </p>

  1151. </dd>

  1152. <dt>&lsquo;<samp>cos(x)</samp>&rsquo;</dt>

  1153. <dd><p>Compute cosine of <var>x</var>.

  1154. </p>

  1155. </dd>

  1156. <dt>&lsquo;<samp>cosh(x)</samp>&rsquo;</dt>

  1157. <dd><p>Compute hyperbolic cosine of <var>x</var>.

  1158. </p>

  1159. </dd>

  1160. <dt>&lsquo;<samp>eq(x, y)</samp>&rsquo;</dt>

  1161. <dd><p>Return 1 if <var>x</var> and <var>y</var> are equivalent, 0 otherwise.

  1162. </p>

  1163. </dd>

  1164. <dt>&lsquo;<samp>exp(x)</samp>&rsquo;</dt>

  1165. <dd><p>Compute exponential of <var>x</var> (with base <code>e</code>, the Euler&rsquo;s number).

  1166. </p>

  1167. </dd>

  1168. <dt>&lsquo;<samp>floor(expr)</samp>&rsquo;</dt>

  1169. <dd><p>Round the value of expression <var>expr</var> downwards to the nearest

  1170. integer. For example, &quot;floor(-1.5)&quot; is &quot;-2.0&quot;.

  1171. </p>

  1172. </dd>

  1173. <dt>&lsquo;<samp>gauss(x)</samp>&rsquo;</dt>

  1174. <dd><p>Compute Gauss function of <var>x</var>, corresponding to

  1175. <code>exp(-x*x/2) / sqrt(2*PI)</code>.

  1176. </p>

  1177. </dd>

  1178. <dt>&lsquo;<samp>gcd(x, y)</samp>&rsquo;</dt>

  1179. <dd><p>Return the greatest common divisor of <var>x</var> and <var>y</var>. If both <var>x</var> and

  1180. <var>y</var> are 0 or either or both are less than zero then behavior is undefined.

  1181. </p>

  1182. </dd>

  1183. <dt>&lsquo;<samp>gt(x, y)</samp>&rsquo;</dt>

  1184. <dd><p>Return 1 if <var>x</var> is greater than <var>y</var>, 0 otherwise.

  1185. </p>

  1186. </dd>

  1187. <dt>&lsquo;<samp>gte(x, y)</samp>&rsquo;</dt>

  1188. <dd><p>Return 1 if <var>x</var> is greater than or equal to <var>y</var>, 0 otherwise.

  1189. </p>

  1190. </dd>

  1191. <dt>&lsquo;<samp>hypot(x, y)</samp>&rsquo;</dt>

  1192. <dd><p>This function is similar to the C function with the same name; it returns

  1193. &quot;sqrt(<var>x</var>*<var>x</var> + <var>y</var>*<var>y</var>)&quot;, the length of the hypotenuse of a

  1194. right triangle with sides of length <var>x</var> and <var>y</var>, or the distance of the

  1195. point (<var>x</var>, <var>y</var>) from the origin.

  1196. </p>

  1197. </dd>

  1198. <dt>&lsquo;<samp>if(x, y)</samp>&rsquo;</dt>

  1199. <dd><p>Evaluate <var>x</var>, and if the result is non-zero return the result of

  1200. the evaluation of <var>y</var>, return 0 otherwise.

  1201. </p>

  1202. </dd>

  1203. <dt>&lsquo;<samp>if(x, y, z)</samp>&rsquo;</dt>

  1204. <dd><p>Evaluate <var>x</var>, and if the result is non-zero return the evaluation

  1205. result of <var>y</var>, otherwise the evaluation result of <var>z</var>.

  1206. </p>

  1207. </dd>

  1208. <dt>&lsquo;<samp>ifnot(x, y)</samp>&rsquo;</dt>

  1209. <dd><p>Evaluate <var>x</var>, and if the result is zero return the result of the

  1210. evaluation of <var>y</var>, return 0 otherwise.

  1211. </p>

  1212. </dd>

  1213. <dt>&lsquo;<samp>ifnot(x, y, z)</samp>&rsquo;</dt>

  1214. <dd><p>Evaluate <var>x</var>, and if the result is zero return the evaluation

  1215. result of <var>y</var>, otherwise the evaluation result of <var>z</var>.

  1216. </p>

  1217. </dd>

  1218. <dt>&lsquo;<samp>isinf(x)</samp>&rsquo;</dt>

  1219. <dd><p>Return 1.0 if <var>x</var> is +/-INFINITY, 0.0 otherwise.

  1220. </p>

  1221. </dd>

  1222. <dt>&lsquo;<samp>isnan(x)</samp>&rsquo;</dt>

  1223. <dd><p>Return 1.0 if <var>x</var> is NAN, 0.0 otherwise.

  1224. </p>

  1225. </dd>

  1226. <dt>&lsquo;<samp>ld(var)</samp>&rsquo;</dt>

  1227. <dd><p>Load the value of the internal variable with number

  1228. <var>var</var>, which was previously stored with st(<var>var</var>, <var>expr</var>).

  1229. The function returns the loaded value.

  1230. </p>

  1231. </dd>

  1232. <dt>&lsquo;<samp>lerp(x, y, z)</samp>&rsquo;</dt>

  1233. <dd><p>Return linear interpolation between <var>x</var> and <var>y</var> by amount of <var>z</var>.

  1234. </p>

  1235. </dd>

  1236. <dt>&lsquo;<samp>log(x)</samp>&rsquo;</dt>

  1237. <dd><p>Compute natural logarithm of <var>x</var>.

  1238. </p>

  1239. </dd>

  1240. <dt>&lsquo;<samp>lt(x, y)</samp>&rsquo;</dt>

  1241. <dd><p>Return 1 if <var>x</var> is lesser than <var>y</var>, 0 otherwise.

  1242. </p>

  1243. </dd>

  1244. <dt>&lsquo;<samp>lte(x, y)</samp>&rsquo;</dt>

  1245. <dd><p>Return 1 if <var>x</var> is lesser than or equal to <var>y</var>, 0 otherwise.

  1246. </p>

  1247. </dd>

  1248. <dt>&lsquo;<samp>max(x, y)</samp>&rsquo;</dt>

  1249. <dd><p>Return the maximum between <var>x</var> and <var>y</var>.

  1250. </p>

  1251. </dd>

  1252. <dt>&lsquo;<samp>min(x, y)</samp>&rsquo;</dt>

  1253. <dd><p>Return the minimum between <var>x</var> and <var>y</var>.

  1254. </p>

  1255. </dd>

  1256. <dt>&lsquo;<samp>mod(x, y)</samp>&rsquo;</dt>

  1257. <dd><p>Compute the remainder of division of <var>x</var> by <var>y</var>.

  1258. </p>

  1259. </dd>

  1260. <dt>&lsquo;<samp>not(expr)</samp>&rsquo;</dt>

  1261. <dd><p>Return 1.0 if <var>expr</var> is zero, 0.0 otherwise.

  1262. </p>

  1263. </dd>

  1264. <dt>&lsquo;<samp>pow(x, y)</samp>&rsquo;</dt>

  1265. <dd><p>Compute the power of <var>x</var> elevated <var>y</var>, it is equivalent to

  1266. &quot;(<var>x</var>)^(<var>y</var>)&quot;.

  1267. </p>

  1268. </dd>

  1269. <dt>&lsquo;<samp>print(t)</samp>&rsquo;</dt>

  1270. <dt>&lsquo;<samp>print(t, l)</samp>&rsquo;</dt>

  1271. <dd><p>Print the value of expression <var>t</var> with loglevel <var>l</var>. If

  1272. <var>l</var> is not specified then a default log level is used.

  1273. Returns the value of the expression printed.

  1274. </p>

  1275. <p>Prints t with loglevel l

  1276. </p>

  1277. </dd>

  1278. <dt>&lsquo;<samp>random(x)</samp>&rsquo;</dt>

  1279. <dd><p>Return a pseudo random value between 0.0 and 1.0. <var>x</var> is the index of the

  1280. internal variable which will be used to save the seed/state.

  1281. </p>

  1282. </dd>

  1283. <dt>&lsquo;<samp>root(expr, max)</samp>&rsquo;</dt>

  1284. <dd><p>Find an input value for which the function represented by <var>expr</var>

  1285. with argument <var>ld(0)</var> is 0 in the interval 0..<var>max</var>.

  1286. </p>

  1287. <p>The expression in <var>expr</var> must denote a continuous function or the

  1288. result is undefined.

  1289. </p>

  1290. <p><var>ld(0)</var> is used to represent the function input value, which means

  1291. that the given expression will be evaluated multiple times with

  1292. various input values that the expression can access through

  1293. <code>ld(0)</code>. When the expression evaluates to 0 then the

  1294. corresponding input value will be returned.

  1295. </p>

  1296. </dd>

  1297. <dt>&lsquo;<samp>round(expr)</samp>&rsquo;</dt>

  1298. <dd><p>Round the value of expression <var>expr</var> to the nearest integer. For example, &quot;round(1.5)&quot; is &quot;2.0&quot;.

  1299. </p>

  1300. </dd>

  1301. <dt>&lsquo;<samp>sgn(x)</samp>&rsquo;</dt>

  1302. <dd><p>Compute sign of <var>x</var>.

  1303. </p>

  1304. </dd>

  1305. <dt>&lsquo;<samp>sin(x)</samp>&rsquo;</dt>

  1306. <dd><p>Compute sine of <var>x</var>.

  1307. </p>

  1308. </dd>

  1309. <dt>&lsquo;<samp>sinh(x)</samp>&rsquo;</dt>

  1310. <dd><p>Compute hyperbolic sine of <var>x</var>.

  1311. </p>

  1312. </dd>

  1313. <dt>&lsquo;<samp>sqrt(expr)</samp>&rsquo;</dt>

  1314. <dd><p>Compute the square root of <var>expr</var>. This is equivalent to

  1315. &quot;(<var>expr</var>)^.5&quot;.

  1316. </p>

  1317. </dd>

  1318. <dt>&lsquo;<samp>squish(x)</samp>&rsquo;</dt>

  1319. <dd><p>Compute expression <code>1/(1 + exp(4*x))</code>.

  1320. </p>

  1321. </dd>

  1322. <dt>&lsquo;<samp>st(var, expr)</samp>&rsquo;</dt>

  1323. <dd><p>Store the value of the expression <var>expr</var> in an internal

  1324. variable. <var>var</var> specifies the number of the variable where to

  1325. store the value, and it is a value ranging from 0 to 9. The function

  1326. returns the value stored in the internal variable.

  1327. Note, Variables are currently not shared between expressions.

  1328. </p>

  1329. </dd>

  1330. <dt>&lsquo;<samp>tan(x)</samp>&rsquo;</dt>

  1331. <dd><p>Compute tangent of <var>x</var>.

  1332. </p>

  1333. </dd>

  1334. <dt>&lsquo;<samp>tanh(x)</samp>&rsquo;</dt>

  1335. <dd><p>Compute hyperbolic tangent of <var>x</var>.

  1336. </p>

  1337. </dd>

  1338. <dt>&lsquo;<samp>taylor(expr, x)</samp>&rsquo;</dt>

  1339. <dt>&lsquo;<samp>taylor(expr, x, id)</samp>&rsquo;</dt>

  1340. <dd><p>Evaluate a Taylor series at <var>x</var>, given an expression representing

  1341. the <code>ld(id)</code>-th derivative of a function at 0.

  1342. </p>

  1343. <p>When the series does not converge the result is undefined.

  1344. </p>

  1345. <p><var>ld(id)</var> is used to represent the derivative order in <var>expr</var>,

  1346. which means that the given expression will be evaluated multiple times

  1347. with various input values that the expression can access through

  1348. <code>ld(id)</code>. If <var>id</var> is not specified then 0 is assumed.

  1349. </p>

  1350. <p>Note, when you have the derivatives at y instead of 0,

  1351. <code>taylor(expr, x-y)</code> can be used.

  1352. </p>

  1353. </dd>

  1354. <dt>&lsquo;<samp>time(0)</samp>&rsquo;</dt>

  1355. <dd><p>Return the current (wallclock) time in seconds.

  1356. </p>

  1357. </dd>

  1358. <dt>&lsquo;<samp>trunc(expr)</samp>&rsquo;</dt>

  1359. <dd><p>Round the value of expression <var>expr</var> towards zero to the nearest

  1360. integer. For example, &quot;trunc(-1.5)&quot; is &quot;-1.0&quot;.

  1361. </p>

  1362. </dd>

  1363. <dt>&lsquo;<samp>while(cond, expr)</samp>&rsquo;</dt>

  1364. <dd><p>Evaluate expression <var>expr</var> while the expression <var>cond</var> is

  1365. non-zero, and returns the value of the last <var>expr</var> evaluation, or

  1366. NAN if <var>cond</var> was always false.

  1367. </p></dd>

  1368. </dl>

  1369. 

  1370. <p>The following constants are available:

  1371. </p><dl compact="compact">

  1372. <dt>&lsquo;<samp>PI</samp>&rsquo;</dt>

  1373. <dd><p>area of the unit disc, approximately 3.14

  1374. </p></dd>

  1375. <dt>&lsquo;<samp>E</samp>&rsquo;</dt>

  1376. <dd><p>exp(1) (Euler&rsquo;s number), approximately 2.718

  1377. </p></dd>

  1378. <dt>&lsquo;<samp>PHI</samp>&rsquo;</dt>

  1379. <dd><p>golden ratio (1+sqrt(5))/2, approximately 1.618

  1380. </p></dd>

  1381. </dl>

  1382. 

  1383. <p>Assuming that an expression is considered &quot;true&quot; if it has a non-zero

  1384. value, note that:

  1385. </p>

  1386. <p><code>*</code> works like AND

  1387. </p>

  1388. <p><code>+</code> works like OR

  1389. </p>

  1390. <p>For example the construct:

  1391. </p><div class="example">

  1392. <pre class="example">if (A AND B) then C

  1393. </pre></div>

  1394. <p>is equivalent to:

  1395. </p><div class="example">

  1396. <pre class="example">if(A*B, C)

  1397. </pre></div>

  1398. 

  1399. <p>In your C code, you can extend the list of unary and binary functions,

  1400. and define recognized constants, so that they are available for your

  1401. expressions.

  1402. </p>

  1403. <p>The evaluator also recognizes the International System unit prefixes.

  1404. If &rsquo;i&rsquo; is appended after the prefix, binary prefixes are used, which

  1405. are based on powers of 1024 instead of powers of 1000.

  1406. The &rsquo;B&rsquo; postfix multiplies the value by 8, and can be appended after a

  1407. unit prefix or used alone. This allows using for example &rsquo;KB&rsquo;, &rsquo;MiB&rsquo;,

  1408. &rsquo;G&rsquo; and &rsquo;B&rsquo; as number postfix.

  1409. </p>

  1410. <p>The list of available International System prefixes follows, with

  1411. indication of the corresponding powers of 10 and of 2.

  1412. </p><dl compact="compact">

  1413. <dt>&lsquo;<samp>y</samp>&rsquo;</dt>

  1414. <dd><p>10^-24 / 2^-80

  1415. </p></dd>

  1416. <dt>&lsquo;<samp>z</samp>&rsquo;</dt>

  1417. <dd><p>10^-21 / 2^-70

  1418. </p></dd>

  1419. <dt>&lsquo;<samp>a</samp>&rsquo;</dt>

  1420. <dd><p>10^-18 / 2^-60

  1421. </p></dd>

  1422. <dt>&lsquo;<samp>f</samp>&rsquo;</dt>

  1423. <dd><p>10^-15 / 2^-50

  1424. </p></dd>

  1425. <dt>&lsquo;<samp>p</samp>&rsquo;</dt>

  1426. <dd><p>10^-12 / 2^-40

  1427. </p></dd>

  1428. <dt>&lsquo;<samp>n</samp>&rsquo;</dt>

  1429. <dd><p>10^-9 / 2^-30

  1430. </p></dd>

  1431. <dt>&lsquo;<samp>u</samp>&rsquo;</dt>

  1432. <dd><p>10^-6 / 2^-20

  1433. </p></dd>

  1434. <dt>&lsquo;<samp>m</samp>&rsquo;</dt>

  1435. <dd><p>10^-3 / 2^-10

  1436. </p></dd>

  1437. <dt>&lsquo;<samp>c</samp>&rsquo;</dt>

  1438. <dd><p>10^-2

  1439. </p></dd>

  1440. <dt>&lsquo;<samp>d</samp>&rsquo;</dt>

  1441. <dd><p>10^-1

  1442. </p></dd>

  1443. <dt>&lsquo;<samp>h</samp>&rsquo;</dt>

  1444. <dd><p>10^2

  1445. </p></dd>

  1446. <dt>&lsquo;<samp>k</samp>&rsquo;</dt>

  1447. <dd><p>10^3 / 2^10

  1448. </p></dd>

  1449. <dt>&lsquo;<samp>K</samp>&rsquo;</dt>

  1450. <dd><p>10^3 / 2^10

  1451. </p></dd>

  1452. <dt>&lsquo;<samp>M</samp>&rsquo;</dt>

  1453. <dd><p>10^6 / 2^20

  1454. </p></dd>

  1455. <dt>&lsquo;<samp>G</samp>&rsquo;</dt>

  1456. <dd><p>10^9 / 2^30

  1457. </p></dd>

  1458. <dt>&lsquo;<samp>T</samp>&rsquo;</dt>

  1459. <dd><p>10^12 / 2^40

  1460. </p></dd>

  1461. <dt>&lsquo;<samp>P</samp>&rsquo;</dt>

  1462. <dd><p>10^15 / 2^40

  1463. </p></dd>

  1464. <dt>&lsquo;<samp>E</samp>&rsquo;</dt>

  1465. <dd><p>10^18 / 2^50

  1466. </p></dd>

  1467. <dt>&lsquo;<samp>Z</samp>&rsquo;</dt>

  1468. <dd><p>10^21 / 2^60

  1469. </p></dd>

  1470. <dt>&lsquo;<samp>Y</samp>&rsquo;</dt>

  1471. <dd><p>10^24 / 2^70

  1472. </p></dd>

  1473. </dl>

  1474. 

  1475. 

  1476. <a name="See-Also"></a>

  1477. <h1 class="chapter"><a href="ffmpeg-utils.html#toc-See-Also">4 See Also</a></h1>

  1478. 

  1479. <p><a href="ffmpeg.html">ffmpeg</a>, <a href="ffplay.html">ffplay</a>, <a href="ffprobe.html">ffprobe</a>,

  1480. <a href="libavutil.html">libavutil</a>

  1481. </p>

  1482. 

  1483. <a name="Authors"></a>

  1484. <h1 class="chapter"><a href="ffmpeg-utils.html#toc-Authors">5 Authors</a></h1>

  1485. 

  1486. <p>The FFmpeg developers.

  1487. </p>

  1488. <p>For details about the authorship, see the Git history of the project

  1489. (git://source.ffmpeg.org/ffmpeg), e.g. by typing the command

  1490. <code>git log</code> in the FFmpeg source directory, or browsing the

  1491. online repository at <a href="http://source.ffmpeg.org">http://source.ffmpeg.org</a>.

  1492. </p>

  1493. <p>Maintainers for the specific components are listed in the file

  1494. &lsquo;<tt>MAINTAINERS</tt>&rsquo; in the source code tree.

  1495. </p>

  1496. 

  1497.     </div>

  1498.   </body>

  1499. </html>