ESP32 Codec2

[flows0247]

Hi,
Im trying to encode recoded speech using codec2 so I included "AudioTools/AudioCodecs/CodecCodec2.h" in the code.
But when I compile I get alot of errors that seem to be due to use of complex variables.
For example, first error:
\Arduino\libraries\codec2\src\modem_probe.h:124:58: error: unknown type name 'complex'; did you mean 'complex int'? 124 | static inline void modem_probe_samp_cft(const char *name,complex float samp[],size_t cnt){ | ^~~~~~~ | complex int

Code:
#include "AudioTools.h" #include "AudioTools/AudioCodecs/CodecCodec2.h" void setup() {} void loop() {}

Did anyone use codec2 with audio tools and ESP32?
Any suggustions how to proceed?
BR Fredrik

[pschatzmann]

That's a bug in the ESP32 Arduino Core that has never been fixed.
It is still open also with the new 3.1 release. So the only way would be to downgrade to 3.0.7 or use another Microcontroller.

[pschatzmann]

You can try to use the esp32-fix branch of the codec2 libaray

[flows0247]

Thanks! It compiles after deleting complex.h in espressif__esp-tflite-micro directory.

Now I'm trying to encode a white noise signal but I get a 200kb file from a 5 second input signal.
Im expecting a smaller file because I get about the same filesize when saving a raw signal.
The file is mostly filled with zeroes.
Im thinking about removing the zeroes to test if I get a correct codec2 file.
I'm happy to receive any suggestions.
BR Fredrik

Output:
`
21:20:06.288 -> [I] AudioTypes.h : 128 - SoundGenerator: sample_rate: 44100 / channels: 1 / bits_per_sample: 16
21:20:06.288 -> [I] Buffers.h : 376 - resize: 2
21:20:06.288 -> [I] AudioTypes.h : 128 - SoundGenerator: sample_rate: 44100 / channels: 1 / bits_per_sample: 16
21:20:06.288 -> [I] AudioTypes.h : 128 - in: sample_rate: 8000 / channels: 1 / bits_per_sample: 16
21:20:06.323 -> [I] AudioTypes.h : 128 - out: sample_rate: 8000 / channels: 1 / bits_per_sample: 16
21:20:06.323 -> [I] CodecCodec2.h : 213 - virtual bool audio_tools::Codec2Encoder::begin()
21:20:06.323 -> [I] CodecCodec2.h : 242 - bytesCompressed:8
21:20:06.323 -> [I] CodecCodec2.h : 243 - bytesUncompressed:320
21:20:07.297 -> [I] StreamCopy.h : 163 - StreamCopy::copy 1024 -> 1024 -> 1024 bytes - in 1 hops
21:20:08.055 -> [I] StreamCopy.h : 163 - StreamCopy::copy 1024 -> 1024 -> 1024 bytes - in 1 hops
21:20:08.921 -> [I] StreamCopy.h : 163 - StreamCopy::copy 1024 -> 1024 -> 1024 bytes - in 1 hops
21:20:09.808 -> [I] StreamCopy.h : 163 - StreamCopy::copy 1024 -> 1024 -> 1024 bytes - in 1 hops
21:20:10.542 -> [I] StreamCopy.h : 163 - StreamCopy::copy 1024 -> 1024 -> 1024 bytes - in 1 hops

`

Sketch:
`SET_LOOP_TASK_STACK_SIZE(32*1024);

#include "AudioTools.h"
#include "AudioTools/AudioCodecs/CodecCodec2.h"

#include "FS.h"
#include "SD_MMC.h"

WhiteNoiseGenerator<int16_t> noise(32000); // subclass of SoundGenerator with max amplitude of 32000
GeneratedSoundStream<int16_t> in_stream(noise); // Stream generated from sine wave

File audioFile; // final output stream

EncodedAudioStream out_stream(&audioFile, new Codec2Encoder());
StreamCopy copier(out_stream, in_stream); // copies sound to out

void setup(){
Serial.begin(115200);

pinMode(15, INPUT_PULLUP); //SD_MMC pins
pinMode(2, INPUT_PULLUP);
pinMode(4, INPUT_PULLUP);
pinMode(12, INPUT_PULLUP);
pinMode(13, INPUT_PULLUP);
if(!SD_MMC.begin()){
Serial.println("Card Mount Failed");
return;
}

AudioLogger::instance().begin(Serial, AudioLogger::Info);

auto cfg = noise.defaultConfig();
cfg.sample_rate = 44100;
cfg.channels = 1;
cfg.bits_per_sample = 16;
noise.begin(cfg);
in_stream.begin();

cfg.sample_rate = 8000;
cfg.channels = 1;
cfg.bits_per_sample = 16;
out_stream.begin(cfg); //Codec2 wont active if cfg is not passed..

audioFile = SD_MMC.open("/002.wav", FILE_WRITE);
}

void loop(){
copier.copy();
audioFile.flush(); // force write down of data
}`

Codec2 file beginning:
`
00000000: | 0dc1 | ca43 | 9ea4 | 3b0a
00000008: | 0000 | 0000 | 0000 | 0000
00000010: | 0000 | 0000 | 0000 | 0000
00000018: | 0000 | 0000 | 0000 | 0000
00000020: | 0000 | 0000 | 0000 | 0000
00000028: | 0000 | 0000 | 0000 | 0000
00000030: | 0000 | 0000 | 0000 | 0000
00000038: | 0000 | 0000 | 0000 | 0000
00000040: | 0000 | 0000 | 0000 | 0000
00000048: | 0000 | 0000 | 0000 | 0000
00000050: | 0000 | 0000 | 0000 | 0000
00000058: | 0000 | 0000 | 0000 | 0000
00000060: | 0000 | 0000 | 0000 | 0000
00000068: | 0000 | 0000 | 0000 | 0000
00000070: | 0000 | 0000 | 0000 | 0000
00000078: | 0000 | 0000 | 0000 | 0000
00000080: | 0000 | 0000 | 0000 | 0000
00000088: | 0000 | 0000 | 0000 | 0000
00000090: | 0000 | 0000 | 0000 | 0000
00000098: | 0000 | 0000 | 0000 | 0000
000000a0: | 0000 | 0000 | 0000 | 0000
000000a8: | 0000 | 0000 | 0000 | 0000
000000b0: | 0000 | 0000 | 0000 | 0000
000000b8: | 0000 | 0000 | 0000 | 0000
000000c0: | 0000 | 0000 | 0000 | 0000
000000c8: | 0000 | 0000 | 0000 | 0000
000000d0: | 0000 | 0000 | 0000 | 0000
000000d8: | 0000 | 0000 | 0000 | 0000
000000e0: | 0000 | 0000 | 0000 | 0000
000000e8: | 0000 | 0000 | 0000 | 0000
000000f0: | 0000 | 0000 | 0000 | 0000
000000f8: | 0000 | 0000 | 0000 | 0000
00000100: | 0000 | 0000 | 0000 | 0000
00000108: | 0000 | 0000 | 0000 | 0000
00000110: | 0000 | 0000 | 0000 | 0000
00000118: | 0000 | 0000 | 0000 | 0000
00000120: | 0000 | 0000 | 0000 | 0000
00000128: | 0000 | 0000 | 0000 | 0000
00000130: | 0000 | 0000 | 0000 | 0000
00000138: | 0000 | 0000 | 0000 | 0000
00000140: | 0fc1 | c953 | 9eb5 | ab2d
00000148: | 0000 | 0000 | 0000 | 0000
00000150: | 0000 | 0000 | 0000 | 0000
00000158: | 0000 | 0000 | 0000 | 0000

...
`

[pschatzmann]

I am sorry, I am not really familiar with the internal working of this codec.
Maybe there are some better alternatives.

https://www.pschatzmann.ch/home/2023/05/10/fast-audio-codecs-for-microcontrollers/