Files
squeezelite-esp32/components/audio/inc/esp_equalizer.h
2020-04-17 08:03:17 -07:00

79 lines
2.4 KiB
C

// Copyright 2018 Espressif Systems (Shanghai) PTE LTD
// All rights reserved.
#ifndef _ESP_EQUALIZER_H
#define _ESP_EQUALIZER_H
#ifdef __cplusplus
extern "C"
{
#endif
/**
* @brief Initialize the equalizer handle
*
* @param nch The audio channel number
* @param g_rate The audio sample rate. Four sample rates are supported: 11025Hz, 22050Hz, 44100Hz and 48000Hz.
* @param n_band The number of audio sub-bands. Fixed number of 10 sub-bands is supported and this value should be set to 10.
* @param use_xmms_original_freqs Currently should be set 0
*
* @return The equalizer handle.
*/
void *esp_equalizer_init(int nch, int g_rate, int n_band, int use_xmms_original_freqs);
/**
* @brief Uninitialize the equalizer handle.
*
* @param handle The the equalizer handle
*/
void esp_equalizer_uninit(void *handle);
/**
* @brief Process the data through the equalizer
*
* @param handle The the equalizer handle
* @param pcm_buf The audio pcm input & output buffer
* @param length The length of current bytes in pcm_buf
* @param g_rate The audio sample rate. Four sample rates are supported: 11025Hz, 22050Hz, 44100Hz and 48000Hz.
* @param nch The audio channel number
*
* @return Length of pcm_buf after processing
*/
int esp_equalizer_process(void *handle, unsigned char *pcm_buf, int length, int g_rate, int nch);
/**
* @brief Set the number of sub-bands for the equalizer
*
* @param handle The the equalizer handle
* @param value The audio sub-bands gain. unit:db. 0 means no gain.
* @param index The index of audio sub-bands. e.g. 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
* @param nch The audio channel number
*/
void esp_equalizer_set_band_value(void *handle, float value, int index, int nch);
/**
* @brief Get the number of the equalizer sub-bands
*
* @param handle The the equalizer handle
*
* @return The number of the equalizer sub-bands
*/
int esp_equalizer_get_band_count(void *handle);
/**
* @brief Get the value of the equalizer sub-bands
*
* @param handle The the equalizer handle
* @param index The index of audio sub-bands. Currently only support 10 sub-bands, so it should be 0-9.
* @param nch The audio channel number
*
* @return The number of the equalizer sub-bands
*/
float esp_equalizer_get_band_value(void *handle, int index, int nch);
#ifdef __cplusplus
}
#endif
#endif