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managed_components/espressif__esp-dsp/applications/spectrum_box_lite/README.md

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+# ESP-DSP ESP32-S3-BOX-Lite Board demo application
+
+The demo applications are developed for the ESP32-S3-BOX-Lite development board and demonstrate the usage of FFT functions from the ESP-DSP library.
+This example showcases how to use FFT functionality to process audio stream data.
+The application record sound from two microphones and show the spectrum from them at display as 2D plot.
+
+## Audio Processing Flow
+
+The audio processing flow contains next blocks:
+1. Audio processing task
+    * Read left and right channel data from the microphone
+    * Apply window multiplication to both channels
+    * Process FFT and apply bit reverse
+    * Split complex spectrum from two channels to two spectrums of two real channels
+    * Calculate absolute spectrum and convert it to dB
+    * Calculate moving average of the spectrum
+2. Image Display Task
+    * Read data from the 
+    * Write data from triple buffer to audio codec
+
+## How to use the example
+
+Just flash the application to the ESP32-S3-BOX-Lite development board, and play some music around or start to speak to the board microphones.
+The display will show the real-time spectrum.
+The microphone sensitivity could be adjusted in the code.
+
+### Hardware required
+
+This example does not require any special hardware, and can be run on any common development board.
+
+### Configure the project
+
+Under Component Config ---> DSP Library ---> DSP Optimization, it's possible to choose either the optimized or ANSI implementation, to compare them.
+
+### Build and flash
+
+Build the project and flash it to the board, then run monitor tool to view serial output (replace PORT with serial port name):
+
+```
+idf.py flash monitor
+```
+
+(To exit the serial monitor, type ``Ctrl-]``.)
+
+See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.