Android的位深

# Global configuration section: # - lists input and output devices always present on the device # as well as the output device selected by default. # Devices are designated by a string that corresponds to the enum in audio.h # - defines whether the speaker output path uses DRC # "TRUE" means DRC is enabled, "FALSE" or omission means DRC isn't used. global_configuration { attached_output_devices AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_TELEPHONY_TX default_output_device AUDIO_DEVICE_OUT_SPEAKER attached_input_devices AUDIO_DEVICE_IN_BUILTIN_MIC|AUDIO_DEVICE_IN_BACK_MIC|AUDIO_DEVICE_IN_REMOTE_SUBMIX|AUDIO_DEVICE_IN_TELEPHONY_RX speaker_drc_enabled TRUE } # audio hardware module section: contains descriptors for all audio hw modules present on the # device. Each hw module node is named after the corresponding hw module library base name. # For instance, "primary" corresponds to audio.primary.<device>.so. # The "primary" module is mandatory and must include at least one output with # AUDIO_OUTPUT_FLAG_PRIMARY flag. # Each module descriptor contains one or more output profile descriptors and zero or more # input profile descriptors. Each profile lists all the parameters supported by a given output # or input stream category. # The "channel_masks", "formats", "devices" and "flags" are specified using strings corresponding # to enums in audio.h and audio_policy.h. They are concatenated by use of "|" without space or "\n". audio_hw_modules { primary { outputs { primary { sampling_rates 44100|48000 channel_masks AUDIO_CHANNEL_OUT_STEREO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_ALL_SCO|AUDIO_DEVICE_OUT_AUX_DIGITAL flags AUDIO_OUTPUT_FLAG_PRIMARY } deep_buffer { sampling_rates 8000|11025|12000|16000|22050|24000|32000|44100|48000 channel_masks AUDIO_CHANNEL_OUT_STEREO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_ALL_SCO|AUDIO_DEVICE_OUT_AUX_DIGITAL flags AUDIO_OUTPUT_FLAG_DEEP_BUFFER } hdmi { sampling_rates 44100|48000 channel_masks dynamic formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_OUT_AUX_DIGITAL flags AUDIO_OUTPUT_FLAG_DIRECT } compress_offload { sampling_rates 8000|11025|12000|16000|22050|24000|32000|44100|48000 channel_masks AUDIO_CHANNEL_OUT_MONO|AUDIO_CHANNEL_OUT_STEREO formats AUDIO_FORMAT_MP3|AUDIO_FORMAT_AAC_LC|AUDIO_FORMAT_AAC_HE_V1|AUDIO_FORMAT_AAC_HE_V2 devices AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE flags AUDIO_OUTPUT_FLAG_DIRECT|AUDIO_OUTPUT_FLAG_COMPRESS_OFFLOAD|AUDIO_OUTPUT_FLAG_NON_BLOCKING } voice_tx { sampling_rates 8000|16000|48000 channel_masks AUDIO_CHANNEL_OUT_STEREO|AUDIO_CHANNEL_OUT_MONO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_OUT_TELEPHONY_TX } } inputs { primary { sampling_rates 8000|11025|12000|16000|22050|24000|32000|44100|48000 channel_masks AUDIO_CHANNEL_IN_MONO|AUDIO_CHANNEL_IN_STEREO|AUDIO_CHANNEL_IN_FRONT_BACK formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_IN_BUILTIN_MIC|AUDIO_DEVICE_IN_WIRED_HEADSET|AUDIO_DEVICE_IN_BLUETOOTH_SCO_HEADSET|AUDIO_DEVICE_IN_VOICE_CALL|AUDIO_DEVICE_IN_BACK_MIC } voice_rx { sampling_rates 8000|16000|48000 channel_masks AUDIO_CHANNEL_IN_STEREO|AUDIO_CHANNEL_IN_MONO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_IN_TELEPHONY_RX } } } a2dp { outputs { a2dp { sampling_rates 44100 channel_masks AUDIO_CHANNEL_OUT_STEREO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_OUT_ALL_A2DP } } inputs { a2dp { sampling_rates 44100|48000 channel_masks AUDIO_CHANNEL_IN_MONO|AUDIO_CHANNEL_IN_STEREO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_IN_BLUETOOTH_A2DP } } } usb { outputs { usb_accessory { sampling_rates 44100 channel_masks AUDIO_CHANNEL_OUT_STEREO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_OUT_USB_ACCESSORY } usb_device { sampling_rates dynamic channel_masks dynamic formats dynamic devices AUDIO_DEVICE_OUT_USB_DEVICE } } inputs { usb_device { sampling_rates dynamic channel_masks dynamic formats dynamic devices AUDIO_DEVICE_IN_USB_DEVICE } } } r_submix { outputs { submix { sampling_rates 48000 channel_masks AUDIO_CHANNEL_OUT_STEREO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_OUT_REMOTE_SUBMIX } } inputs { submix { sampling_rates 48000 channel_masks AUDIO_CHANNEL_IN_STEREO formats AUDIO_FORMAT_PCM_16_BIT devices AUDIO_DEVICE_IN_REMOTE_SUBMIX } } } }

float to short

void floattoshort(float * floatbuffer, short * shortbuffer, int length) { for(int i=0; i< length; i++) { float f = floatbuffer[i]; f= f *32768; if(f>32767) f= 32767; if(f<-32768) f= -32768; shortbuffer[i] = (short)f; } }

Stero to Mono

uint32_t lengthIn = framesWritten; int16_t inShort[lengthIn] = { 0 }; if(channelNum == 2) { for (uint32_t i = 0; i < lengthIn; i++) { inShort[i] = (int16_t) ((((int8_t *) shortbuffer)[i * 4] & 0xff) | ((((int8_t *) shortbuffer)[i * 4+ 1] << 8) & 0xff00)); } } else /*channelNum == 1*/ { for (uint32_t i = 0; i < lengthIn; i++) { inShort[i] = (int16_t) ((((int8_t *) shortbuffer)[i * 2] & 0xff) | ((((int8_t *) shortbuffer)[i * 2+ 1] << 8) & 0xff00)); } }