From 310fd066e91f454b990372ffa30e803cc8120975 Mon Sep 17 00:00:00 2001 From: Florian Merz Date: Thu, 11 Feb 2021 12:56:40 +0100 Subject: unslug zh-cn: move --- .../api/audionode/connect(audioparam)/index.html | 163 +++++++++++++++++++++ 1 file changed, 163 insertions(+) create mode 100644 files/zh-cn/orphaned/web/api/audionode/connect(audioparam)/index.html (limited to 'files/zh-cn/orphaned/web/api/audionode/connect(audioparam)') diff --git a/files/zh-cn/orphaned/web/api/audionode/connect(audioparam)/index.html b/files/zh-cn/orphaned/web/api/audionode/connect(audioparam)/index.html new file mode 100644 index 0000000000..eb82534aed --- /dev/null +++ b/files/zh-cn/orphaned/web/api/audionode/connect(audioparam)/index.html @@ -0,0 +1,163 @@ +--- +title: AudioNode.connect(AudioParam) +slug: Web/API/AudioNode/connect(AudioParam) +translation_of: Web/API/AudioNode/connect(AudioParam) +--- +

{{ APIRef("Web Audio API") }}

+ +
+

允许我们将当前节点的一个输出连接到音频参数的一个输入，并允许通过音频信号控制参数。
+ 使AudioNode输出连接到多个AudioParam，并将多个AudioNode输出连接到单个 AudioParam，同时多次调用connect()。因此支持Fan-in and fan-out。
+  AudioParam可以从连接到它的任何AudioNode输出获取渲染的音频数据，并通过下混合将其转换为单声道（如果本身不是单声道的话）。然后，它将其他这样的输出和固定参数混合（ AudioParam的值通常没有任何连接），包括为参数调度的任何时间的变化。
+ 因此，可以通过将AudioParam的值设置为中心频率来选择AudioParam将要更改的范围，并使用音频源和AudioParam之间的GainNode来调整AudioParam更改的范围。

+
+ +

Syntax

+ +
var lfo = audioCtx.createOscillator();
+lfo.frequency.value = 2.0; // Hz, two times per second
+
+var lfoGain = audioCtx.createGain();
+lfoGain.gain.value = 0.5;
+
+// this is the parameter that is going to be modulated
+var gain = audioCtx.createGain();
+gain.gain.value = 0.5;
+
+// Oscillators go from -1 to 1
+// Make it go from -0.5 to +0.5 by connecting it to a GainNode with a gain value of 0.5
+lfo.connect(lfoGain);
+
+// because the value of the gain.gain AudioParam is originaly 0.5, the value is added, and it will go from 0.0 to 1.0
+lfoGain.connect(gain.gain);
+
+lfo.connect(gain.gain);
+ +
+

Note: There can only be one connection between an output from one specific AudioNode and an {{ domxref("AudioParam") }}. Multiple connections to the same termini are equivalent to a single such connection (the duplicates are ignored).

+
+ +

Returns

+ +

Void.

+ +

Example

+ +

In this example, we will be altering the gain value of a {{domxref("GainNode")}} using an {{domxref("OscillatorNode")}} with a slow frequency value. This technique is know as an LFO-controlled parameter.

+ +
var AudioContext = window.AudioContext || window.webkitAudioContext;
+
+var audioCtx = new AudioContext();
+
+// create an normal oscillator to make sound
+var oscillator = audioCtx.createOscillator();
+
+// create a second oscillator that will be used as an LFO (Low-frequency
+// oscillator), and will control a parameter
+var lfo = audioCtx.createOscillator();
+
+// set the frequency of the second oscillator to a low number
+lfo.frequency.value = 2.0; // 2Hz: two oscillations par second
+
+// create a gain whose gain AudioParam will be controlled by the LFO
+var gain = audioCtx.createGain();
+
+// connect the LFO to the gain AudioParam. This means the value of the LFO
+// will not produce any audio, but will change the value of the gain instead
+lfo.connect(gain.gain);
+
+// connect the oscillator that will produce audio to the gain
+oscillator.connect(gain);
+
+// connect the gain to the destination so we hear sound
+gain.connect(audioCtx.destination);
+
+// start the oscillator that will produce audio
+oscillator.start();
+
+// start the oscillator that will modify the gain value
+lfo.start();
+ +

Parameters

+ +
+
Destination
+
The {{ domxref("AudioParam") }} you are connecting to.
+
Output (optional)
+
An index describing which output of the current AudioNode you want to connect to the {{ domxref("AudioParam") }}. The index numbers are defined according to the number of output channels (see Audio channels.)  If this parameter is out-of-bound, an INDEX_SIZE_ERR exception is thrown.
+
+ +

Specifications

+ + + + + + + + + + + + + + +
SpecificationStatusComment
{{SpecName('Web Audio API', '#widl-AudioNode-connect-void-AudioParam-destination-unsigned-long-output', 'connect(AudioParam)')}}{{Spec2('Web Audio API')}} 
+ +

Browser compatibility

+ +
{{CompatibilityTable}}
+ +
+ + + + + + + + + + + + + + + + + + + +
FeatureChromeFirefox (Gecko)Internet ExplorerOperaSafari (WebKit)
connect(AudioParam){{CompatVersionUnknown}} {{property_prefix("webkit")}}{{CompatVersionUnknown}}{{CompatNo}}{{CompatVersionUnknown}}{{CompatNo}}
+
+ +
+ + + + + + + + + + + + + + + + + + + + + +
FeatureAndroidFirefox Mobile (Gecko)Firefox OS (Gecko)IE PhoneOpera MobileSafari Mobile
connect(AudioParam){{CompatNo}}{{CompatVersionUnknown}}{{CompatVersionUnknown}}{{CompatNo}}{{CompatNo}}{{CompatNo}}
+
+ +

See also

+ + -- cgit v1.2.3-54-g00ecf