upload android base code part4

android/compatibility/cdd/5_multimedia/5_11_unprocessed-audio.md

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+## 5.11\. Capture for Unprocessed
+
+Android includes support for recording of unprocessed audio via the
+`android.media.MediaRecorder.AudioSource.UNPROCESSED` audio source. In
+OpenSL ES, it can be accessed with the record preset
+`SL_ANDROID_RECORDING_PRESET_UNPROCESSED`.
+
+If device implementations intent to support unprocessed audio source and make
+it available to third-party apps, they:
+
+*    [C-1-1] MUST report the support through the `android.media.AudioManager`
+property [PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED](http://developer.android.com/reference/android/media/AudioManager.html#PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED).
+
+*    [C-1-2] MUST exhibit approximately flat amplitude-versus-frequency
+characteristics in the mid-frequency range: specifically ±10dB from
+100 Hz to 7000 Hz for each and every microphone used to record the unprocessed
+audio source.
+
+*    [C-1-3] MUST exhibit amplitude levels in the low frequency
+range: specifically from ±20 dB from 5 Hz to 100 Hz compared to the
+mid-frequency range for each and every microphone used to record the
+unprocessed audio source.
+
+*    [C-1-4] MUST exhibit amplitude levels in the high frequency
+range: specifically from ±30 dB from 7000 Hz to 22 KHz compared to the
+mid-frequency range for each and every microphone used to record the
+unprocessed audio source.
+
+*    [C-1-5] MUST set audio input sensitivity such that a 1000 Hz sinusoidal
+tone source played at 94 dB Sound Pressure Level (SPL) yields a response with
+RMS of 520 for 16 bit-samples (or -36 dB Full Scale for floating point/double
+precision samples) for each and every microphone used to record the unprocessed
+audio source.
+
+*    [C-1-6] MUST have a signal-to-noise ratio (SNR) at 60 dB or higher for
+each and every microphone used to record the unprocessed audio source.
+(whereas the SNR is measured as the difference between 94 dB SPL and equivalent
+SPL of self noise, A-weighted).
+
+*    [C-1-7] MUST have a total harmonic distortion (THD) less than be less than
+1% for 1 kHZ at 90 dB SPL input level at each and every microphone used to
+record the unprocessed audio source.
+
+*    MUST not have any other signal processing (e.g. Automatic Gain Control,
+High Pass Filter, or Echo cancellation) in the path other than a level
+multiplier to bring the level to desired range. In other words:
+*    [C-1-8] If any signal processing is present in the architecture for any
+reason, it MUST be disabled and effectively introduce zero delay or extra
+latency to the signal path.
+*    [C-1-9] The level multiplier, while allowed to be on the path, MUST NOT
+introduce delay or latency to the signal path.
+
+All SPL measurements are made directly next to the microphone under test.
+For multiple microphone configurations, these requirements apply to
+each microphone.
+
+If device implementations declare `android.hardware.microphone` but do not
+support unprocessed audio source, they:
+
+*    [C-2-1] MUST return `null` for the `AudioManager.getProperty(PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED)`
+API method, to properly indicate the lack of support.
+*    [SR] are still STRONGLY RECOMMENDED to satisfy as many of the requirements
+for the signal path for the unprocessed recording source.