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diff --git a/docs/xml/http/ngx_http_mp4_module.xml b/docs/xml/http/ngx_http_mp4_module.xml deleted file mode 100644 index 2a385618f..000000000 --- a/docs/xml/http/ngx_http_mp4_module.xml +++ /dev/null @@ -1,156 +0,0 @@ -<?xml version="1.0"?> - -<!DOCTYPE module SYSTEM "../../dtd/module.dtd"> - -<module name="HTTP MP4 Module" id="http_mp4_module"> - -<section name="Summary"> - -<para> -The module <code>ngx_http_mp4_module</code> provides pseudo-streaming -server-side support for H.264/AAC files typically having filename extensions -<pathname>.mp4</pathname>, <pathname>.m4v</pathname>, -and <pathname>.m4a</pathname>. -</para> - -<para> -Pseudo-streaming works in alliance with conformant Flash players. -A player sends an HTTP request to the server with a start time -argument in the request URI’s query string (named simply -<parameter>start</parameter> -and specified in seconds), and the server responds with a stream -so that its start position corresponds to the requested time, -for example: -<example> -http://example.com/elephants_dream.mp4?start=238.88 -</example> -This allows for a random seeking at any time, or starting playback -in the middle of a timeline. -</para> - -<para> -To support seeking, H.264-based formats store the metadata -in the so-called “moov atom.” -It is a part of the file that holds the index information for the -whole file. -</para> - -<para> -To start playback, a player first needs to read metadata. -This is done by sending a special request with the -<parameter>start=0</parameter> -argument. Many encoding software will insert the metadata at -the end of the file. This is bad for pseudo-streaming: -the metadata needs to be located at the beginning of the file, -or else the entire file will have to be downloaded before it -starts playing. If a file is well-formed (with metadata at the -beginning of a file), nginx just sends back the contents of a file. -Otherwise, it has to read the file and prepare a new stream so that -metadata comes before media data. -This involves some CPU, memory, and disk I/O overhead, -so it is a good idea to -<link url="http://flowplayer.org/plugins/streaming/pseudostreaming.html#prepare"> -prepare an original file for pseudo-streaming</link>, -rather than having nginx do this on every such request. -</para> - -<para> -For a matching request with a non-zero -<parameter>start</parameter> -argument, nginx will read metadata from the file, prepare the -stream starting from the requested offset, and send it to a client. -This has the same overhead as described above. -</para> - -<para> -If a matching request does not include the -<parameter>start</parameter> -argument, there is no overhead, and the file is just sent as a static resource. -Some players also support byte-range requests, and thus do not require -this module at all. -</para> - -<para> -This module is not built by default, it should be enabled with the -<code>--with-http_mp4_module</code> -configuration parameter. -<note> -If you were using the third-party mp4 module, be sure to disable it. -</note> -</para> - -<para> -A similar pseudo-streaming support for FLV files is provided by the module -<link doc="ngx_http_flv_module.xml">ngx_http_flv_module</link>. -</para> - -</section> - - -<section id="example" name="Example Configuration"> - -<para> -<example> -location /video/ { - mp4; - mp4_buffer_size 1m; - mp4_max_buffer_size 5m; -} -</example> -</para> - -</section> - - -<section id="directives" name="Directives"> - -<directive name="mp4"> -<syntax>mp4</syntax> -<default/> -<context>location</context> - -<para> -Turns on module processing in a surrounding location. -</para> - -</directive> - - -<directive name="mp4_buffer_size"> -<syntax>mp4_buffer_size <argument>size</argument></syntax> -<default>mp4_buffer_size 512K</default> -<context>http</context> -<context>server</context> -<context>location</context> - -<para> -Sets the initial size of a memory buffer used to process MP4 files. -</para> - -</directive> - - -<directive name="mp4_max_buffer_size"> -<syntax>mp4_max_buffer_size <argument>size</argument></syntax> -<default>mp4_max_buffer_size 10M</default> -<context>http</context> -<context>server</context> -<context>location</context> - -<para> -During metadata processing, a larger buffer may become necessary. -Its size cannot exceed the specified <argument>size</argument>, -or else nginx will return the server error -<http-status code="500" text="Internal Server Error"/>, -and log the following: -<example> -"/some/movie/file.mp4" mp4 moov atom is too large: -12583268, you may want to increase mp4_max_buffer_size -</example> -</para> - -</directive> - -</section> - -</module> |