This app generates white, pink and red noise and lets you make subtle adjustments to noise colour (spectral distribution). It's stable, lightweight, and plays well with the phone's OS and other audio apps, and the UI is simple and functional. It does not play any pre-recorded sounds. This is it in a nutshell. For more detailed information, read on.
WHAT IS IT FOR?
Use Noise Machine with a pair of earphones to mask distracting and annoying sounds and become at peace with the world. Loud conversations at a coffee shop where you are trying to read, crying babies on planes, background music that doesn't agree with your taste and a many other noises get into your brain and have to be processed. All of these sounds have certain patterns and aren't truly random in the mathematical sense. When you are tired or irritable or are getting too distracted, you can let your brain rest by masking these sounds with noise that doesn't have a noticeable pattern. This works remarkably well even at moderate volumes, and you will be able to concentrate or relax much more easily in noisy environments. Even tinnitus can be masked this way. Noise Machine can also be used with a speaker to help put babies (and adults) to sleep. If you intend to stay awake, it's best to use it with headphones or earphones. That way, at least if you picked the right type of noise and the earphones are comfortable, you will quickly stop noticing it; with speakers, every time you move your head, your perception will change, and you will be reminded of the noise, which defeats the purpose. There are also some technical uses, such as testing speaker polarity.
NOISE COLOUR
The terms "white" and "pink" noise refer to random signals with different spectral distributions. In white noise, the noise energy density is constant throughout the frequency spectrum (at least in the range of interest). This is similar to white light, hence the term "white noise". In pink noise, the lower-frequency components are stronger, and the noise energy density is the same in every octave (or decade, or any logarithm of frequency). This is also known as 1/f noise. Similarly, in pink-coloured light, the lower-frequency, longer-wavelength, redder components are stronger.
A more general case is 1/f^α. The value of α=0 corresponds to white noise, or flat frequency spectrum, as described above; α=1 corresponds to pink noise, or -3dB/octave frequency dependence, also as described above (in different words); α=2 to "red" or "brown" noise (which refers to Brownian motion rather than the colour brown), or -6dB/octave frequency dependence. In this app, the alpha value may be adjusted from 0 to 2 in small increments.
LOOPING
Optionally, the sound may be played in a loop, which reduces the already modest CPU and battery usage by only generating the noise clip that's long enough to fill a loop (at the expense of using more RAM to store it, which normally is not a problem). The playback is gapless. If the loop is too short, you will notice a pattern, which will create a distraction, but even the shortest loop setting (1 minute) should be long enough. The longest setting is determined by the amount of memory available to the app (typically 5 minutes). If you think you can still hear a pattern, or need continuous random signal generation for some other purpose, or want the app to use as little RAM as possible, you can turn the loop off.
USE OF THIRD-PARTY WORK
- A modified version of the pink noise generator class, originally written by Sampo Niskanen, distributed under the BSD license
- Modified Android robot image and images from , used according to the Creative Commons Attribution License 3.0
PERMISSIONS
READ_PHONE_STATE -- this is used to pause the noise sound during phone calls.
这个应用程序会产生白色，粉红色和红色的噪音，让您做出细微的调整，以噪音颜色（光谱分布）。它的稳定，重量轻，而且与手机的操作系统和其他应用程序的音频播放不错，而且用户界面是简单而实用。它没有起到任何预先录制的声音。这是它概括地说。如需更详细的信息，请继续阅读。
它有什么作用？
使用噪声机配一副耳机来掩盖分散和恼人的声音，成为和平的世界。在咖啡馆，你试图阅读，哭闹的婴儿在飞机上，背景音乐，不同意你的味道和许多其他的噪音进入你的大脑，而且必须处理大声交谈。所有这些声音有一定的图案，并不真正随机的数学意义。当你疲倦或烦躁或变得过于分心，您可以通过不具有明显的图案噪声掩蔽这些声音让你的大脑休息。这工作得非常好，即使在中等量，你将能够在嘈杂的环境中集中或放松更容易。耳鸣甚至可以屏蔽这种方式。噪声机也可以与扬声器用于帮助把婴儿及成人睡觉。如果你打算保持清醒，也最好使用耳机或耳塞。这样一来，至少如果你选择了正确类型的噪声和耳机都舒服，你很快就会停止注意到它;有扬声器，每次移动你的头，你的观念将发生变化，你会被提醒了噪音，从而违背了目的的。也有一些专门技术用途，如测试扬声器极性。
色噪声
术语“白”和“粉红”噪声是指随机信号具有不同的光谱分布。在白噪声，噪声能量密度是恒定的整个频谱（至少在感兴趣的范围内）。这类似于白色光，因此称为“白噪声”。粉红噪音，低频率成分都强，噪声能量密度是每倍频程（或十年，或频率的任何对数）是相同的。这也被称为1 / f噪声。同样，在粉红色的光，较低频率，波长较长，较红的成分是强。
一个更普遍的情况是的1 / f ^α。 α= 0时的值对应于白噪声，或平坦频谱，如上面所描述的; α= 1对应的粉红噪声，或-3dB/octave频率依赖性，上面（在不同的字）也描述; 2 =α，以“红”或“棕色”噪声（指布朗运动而不是颜色褐色），或-6dB/octave频率依赖性。在这个程序中，alpha值可以从0到2小的增量调整。
LOOPING
或者，声音可能在一个循环，它通过只产生噪音剪辑的时间足够长，以填补一个循环（在使用更多的内存来存储它，这通常是不为代价减少令本已疲弱的CPU和电池使用上播放的问题）。播放的是无间隙。如果循环太短，你会发现一个模式，这将创建一个分心，但即使是最短的循环设置（1分钟）应足够长。最长的设置是由可用的内存的应用程序的数量（通常为5分钟）来确定。如果你认为你仍然可以听到一个模式，或者需要连续随机信号生成用于其他目的，或希望应用程序使用较小的内存，可能的话，你可以把循环关闭。
 使用第三方工作
- 粉红噪声发生器类的修改版本，最初由声宝尼斯卡宁，在BSD许可证下的分布式
- 修改了Android的机器人形象和图像，根据知识共享署名3.0许可使用
PERMISSIONS
READ_PHONE_STATE - 这是用来在通话期间暂停噪声声。
 

噪音消除器更新内容

Version 1.2.2: added timer, menu with links to trim the volume, donate money and leave feedback; added diagnostic info for occasional problems in loop mode on devices with low available memory.