85 lines
2.4 KiB
Clojure
85 lines
2.4 KiB
Clojure
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=== Objectif ===
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:** Understand write audio stream
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=== sample source: ===
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[[http://github.com/HeeroYui/river.git/sample/write/ | sample source]]
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=== Bases: ===
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The writing work nearly like the read turoral. Then we will just see what has change.
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==== File configuration: ====
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[code style=c++]
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static const std::string configurationRiver =
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"{\n"
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" speaker:{\n"
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" io:'output',\n"
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" map-on:{\n"
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" interface:'auto',\n"
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" name:'default',\n"
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" },\n"
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" frequency:0,\n"
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" channel-map:['front-left', 'front-right'],\n"
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" type:'auto',\n"
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" nb-chunk:1024,\n"
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" volume-name:'MASTER'\n"
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" }\n"
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"}\n";
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[/code]
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==== Create your write interface: ====
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[code style=c++]
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// create interface:
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std11::shared_ptr<river::Interface> interface;
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//Get the generic input:
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interface = manager->createOutput(48000,
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std::vector<audio::channel>(),
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audio::format_int16,
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"speaker");
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[/code]
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Here we create an interface with:
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:** The frequency of 48000 Hz.
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:** The default Low level definition channel
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:** A data interface of 16 bits samples coded in [-32768..32767]
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:** Select input interaface name "speaker"
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==== write datas: ====
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The best way to get data is to instanciate a simple callback.
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The callback is called when sample are needed and you have the nbChunk/frequency
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to generate the data, otherwise you can generate error in data stream.
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[code style=c++]
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// set callback mode ...
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interface->setOutputCallback(std11::bind(&onDataNeeded,
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std11::placeholders::_1,
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std11::placeholders::_2,
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std11::placeholders::_3,
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std11::placeholders::_4,
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std11::placeholders::_5,
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std11::placeholders::_6));
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[/code]
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==== Callback inplementation: ====
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Simply declare your function and do what you want inside.
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[code style=c++]
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void onDataNeeded(void* _data,
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const std11::chrono::system_clock::time_point& _time,
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size_t _nbChunk,
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enum audio::format _format,
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uint32_t _frequency,
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const std::vector<audio::channel>& _map) {
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if (_format == audio::format_int16) {
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// stuff here
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}
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}
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[/code]
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