15b4baba28
- minimize RAM usage of all components - use both IRAM and DRAM in player component so we can buffer up to 1s on modules without SPI RAM - support fragemented pcm chunks so we can use all available RAM if there isn't a big enough block available but still enough HEAP - reinclude all components from jorgen's master branch - add custom i2s driver to get a precise timing of initial sync - change wrong usage of esp_timer for latency measurement of snapcast protocol - add player component
93 lines
2.9 KiB
C
93 lines
2.9 KiB
C
// Copyright 2018-2019 Espressif Systems (Shanghai) PTE LTD
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "freertos/FreeRTOS.h"
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#include "freertos/task.h"
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#include "esp_system.h"
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#include "driver/spi_master.h"
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#include "soc/gpio_struct.h"
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#include "driver/gpio.h"
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#include "driver/uart.h"
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#include "soc/uart_struct.h"
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#include <math.h>
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#include "esp_dsp.h"
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static const char *TAG = "main";
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// This example shows how to use FFT from esp-dsp library
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#define N_SAMPLES 1024
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int N = N_SAMPLES;
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// Input test array
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float x1[N_SAMPLES];
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// Window coefficients
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float wind[N_SAMPLES];
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// working complex array
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float y_cf[N_SAMPLES*2];
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// Pointers to result arrays
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float* y1_cf = &y_cf[0];
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static void process_and_show(float* data, int length)
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{
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dsps_fft2r_fc32(data, length);
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// Bit reverse
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dsps_bit_rev_fc32(data, length);
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// Convert one complex vector to two complex vectors
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dsps_cplx2reC_fc32(data, length);
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for (int i = 0 ; i < length/2 ; i++) {
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data[i] = 10 * log10f((data[i * 2 + 0] * data[i * 2 + 0] + data[i * 2 + 1] * data[i * 2 + 1])/N);
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}
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// Show power spectrum in 64x10 window from -100 to 0 dB from 0..N/4 samples
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dsps_view(data, length/2, 64, 10, -120, 40, '|');
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}
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void app_main()
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{
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esp_err_t ret;
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ESP_LOGI(TAG, "*** Start Example. ***");
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ret = dsps_fft2r_init_fc32(NULL, CONFIG_DSP_MAX_FFT_SIZE);
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if (ret != ESP_OK)
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{
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ESP_LOGE(TAG, "Not possible to initialize FFT. Error = %i", ret);
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return;
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}
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// Generate Hann window
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dsps_wind_hann_f32(wind, N);
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ESP_LOGI(TAG, "*** Multiply tone signal with Hann window by standard C loop. ***");
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// Generate input signal
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dsps_tone_gen_f32(x1, N, 1., 0.2, 0);
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// Convert two input vectors to one complex vector
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for (int i=0 ; i< N ; i++)
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{
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y_cf[i*2 + 0] = x1[i]*wind[i];
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y_cf[i*2 + 1] = 0;
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}
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process_and_show(y_cf, N);
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ESP_LOGI(TAG, "*** Multiply tone signal with Hann window by esp-dsp basic math functions. ***");
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// Convert two input vectors to one complex vector with basic functions
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dsps_mul_f32(x1, wind, y_cf, N, 1, 1, 2); // Multiply input array with window and store as real part
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dsps_mulc_f32(&y_cf[1], &y_cf[1], N, 0, 2, 2); // Clear imaginary part of the complex signal
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process_and_show(y_cf, N);
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ESP_LOGI(TAG, "*** End Example. ***");
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} |