MP3 HEADER DETAILS FROM LIBRARY

[Udaymakxenia]

Hi I was using the library to play mp3 from different urls. I am getting distorted audio when the bit rates are different. Is there a function to get the MP3 header details of a file in an SD card or from the url , so that I can change the sample rates accordingly. Sorry if I have made any newbie mistakes as I am new to audio processing.

[pschatzmann]

That should happen automatically: can you share your example that is not working ?
Did you activate the the log level Info and verified that you do not see any information about updates of the sample rate ?

You could try to add a setNotifyAudioChange(i2s) to the EncodedAudioStream, to make sure that the I2SStream is notified about changes...

[Udaymakxenia]

Hi Phil ,First of all thank you for the quick response. My requirement is to download a file from a url , save it onto an sd card and then play it. I tried your  "streams-url-file" example. But it was not working (attached below the log reports of that).

Then I wrote a custom code by downloading an mp3 file using the HTTP client library , saving it onto the sd card and then playing it (Attached below the code for this). Here I am having trouble playing mp3 files as the playback speed is variable for different files. It would be of great help if you could tell me what I am doing wrong with the  "streams-url-file" example. I will also try the setNotifyAudioChange . Thanks in advance

My code with HTTP Client

#include <WiFi.h>
#include <HTTPClient.h>
#include "FS.h"
#include <SPI.h>
#include <SD.h>
#include "AudioTools.h"
#include "AudioLibs/AudioKit.h"
#include "AudioCodecs/CodecMP3Helix.h"

const char* ssid = "xxid";     // your network SSID (name of wifi network)
const char* password = "pwd"; // your network password

#define PIN_AUDIO_KIT_SD_CARD_CS 13
#define PIN_AUDIO_KIT_SD_CARD_MISO 2
#define PIN_AUDIO_KIT_SD_CARD_MOSI 15
#define PIN_AUDIO_KIT_SD_CARD_CLK  14

//uint16_t sample_rate= 24000;
//uint8_t channels = 2; 
AudioKitStream i2s; // final output of decoded stream
VolumeStream volume(i2s);
EncodedAudioStream decoder(&volume, new MP3DecoderHelix()); // Decoding stream
StreamCopy copier;
float Volume = 0.3;
int b = 1;
void setup() {
  Serial.begin(115200);
  SPI.begin(PIN_AUDIO_KIT_SD_CARD_CLK, PIN_AUDIO_KIT_SD_CARD_MISO, PIN_AUDIO_KIT_SD_CARD_MOSI, PIN_AUDIO_KIT_SD_CARD_CS);
  if (!SD.begin(PIN_AUDIO_KIT_SD_CARD_CS )) {
    //    Serial.println("Card Mount Failed");
    return;
  }
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    //    Serial.println("Connecting to WiFi..");
  }

  Serial.println("Connected to the WiFi network");

}
void loop() {
  if (b) {
    getCalendar();
    delay(1000);
    //    readFile(SD, "/download.mp3");
  }
}

void getCalendar() {
  File file = SD.open("/01/01.mp3", FILE_WRITE);

  if (!file) {
    Serial.println("- failed to open file for writing");
    return;
  }

  if ((WiFi.status() == WL_CONNECTED)) { // Check the current connection status
    Serial.println("Inside connected");
    HTTPClient http;
    http.begin("https://makxenia.com/wp-content/uploads/2022/12/01/01.mp3"); //Specify the URL and certificate
    int httpCode = http.GET(); // Make the request

    if (httpCode == HTTP_CODE_OK) { // Check for the returning code
      Serial.println("Inside Code Ok");
      file.seek(0);
      http.writeToStream(&file);
    }

    file.close();
    Serial.println("you have finished downloading");
    http.end(); // Free the resources
    b = 0;

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

    // setup audiokit before SD!
    auto config = i2s.defaultConfig(TX_MODE);
//    config.sample_rate = sample_rate;
//    config.channels = channels;
    config.sd_active = true;
    i2s.begin(config);

    // set initial volume
    volume.begin(config); // we need to provide the bits_per_sample and channels
    volume.setVolume(Volume);

    // setup file
    //    SD.begin(chipSelect);
    File audioFile;
    audioFile = SD.open("/01/01.mp3");

    // setup I2S based on sampling rate provided by decoder
    decoder.begin();

    // begin copy
    copier.setCheckAvailableForWrite(false);
    copier.begin(decoder, audioFile);
    while (1) {
      if (Serial.available()) {
        char c = Serial.read();
        if (c == 'H') {
          if (Volume > 1.0) {
            Volume = 1.0;
          }
          Volume = Volume + 0.1;
          volume.setVolume(Volume);
        }
        else if (c == 'L') {
          if (Volume < 0.0) {
            Volume = 0.0;
          }
          Volume = Volume - 0.1;
          volume.setVolume(Volume);
        }
      }
      if (!copier.copy()) {
        stop();
      }
    }
    audioFile.close();
  }
  //  Serial.println("Outsude connected");

  delay(1000);
}

[pschatzmann]

I assume the file copy does not work because the method availableForWrite() on a file returns 0. Can you double check ?
If this is the case you could use copier.setCheckAvailableForWrite(false).
The volume is currently notified about audio changes, but does not pass it on to I2S. I guess I should extend the logic a bit...

[Udaymakxenia]

I am using the audiokit v2.2 (photo attached).

I tried adding parameters in the copyAll() function but I am still getting this.

12:26:36.850 -> [I] URLStream.h : 73 - virtual bool audio_tools::URLStreamDefault::begin(const char*, const char*, MethodID, const char*, const char*): https://pschatzmann.github.io/arduino-audio-tools/resources/audio-8000.raw
12:26:36.850 -> [I] Url.h : 73 - Url::parse
12:26:36.850 -> [I] Url.h : 109 - url->https://pschatzmann.github.io/arduino-audio-tools/resources/audio-8000.raw
12:26:36.850 -> [I] Url.h : 110 - host->pschatzmann.github.io
12:26:36.850 -> [I] Url.h : 111 - protocol->https
12:26:36.850 -> [I] Url.h : 112 - path->/arduino-audio-tools/resources/audio-8000.raw
12:26:36.896 -> [I] Url.h : 113 - port->443
12:26:36.990 -> ...
12:26:38.990 -> [I] URLStream.h : 247 - WiFiClientSecure
12:26:38.990 -> [I] URLStream.h : 247 - WiFiClientSecure
12:26:38.990 -> [I] HttpRequest.h : 193 - process connecting to host pschatzmann.github.io port 443
12:26:39.693 -> [I] HttpRequest.h : 181 - connected 1 timeout 60000
12:26:39.693 -> [I] HttpRequest.h : 204 - Free heap: 176376
12:26:39.693 -> [I] HttpHeader.h : 358 - HttpRequestHeader::setValues - path: /arduino-audio-tools/resources/audio-8000.raw
12:26:39.693 -> [I] HttpHeader.h : 255 - HttpHeader::write
12:26:39.693 -> [I] HttpHeader.h : 367 - HttpRequestHeader::write1stLine
12:26:39.693 -> [I] HttpHeader.h : 382 - -> GET /arduino-audio-tools/resources/audio-8000.raw HTTP/1.1
12:26:39.693 -> [I] HttpHeader.h : 192 -  -> Host: pschatzmann.github.io 
12:26:39.693 -> [I] HttpHeader.h : 192 -  -> Connection: close 
12:26:39.693 -> [I] HttpHeader.h : 192 -  -> Accept: */* 
12:26:39.740 -> [I] HttpHeader.h : 298 -  -> <CR LF> 
12:26:39.740 -> [I] HttpRequest.h : 227 - Request written ... waiting for reply
12:26:39.740 -> [I] HttpHeader.h : 225 - HttpHeader::read
12:26:39.740 -> [W] HttpHeader.h : 232 - Waiting for data...
12:26:40.209 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> HTTP/1.1 200 OK
12:26:40.256 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Connection: close
12:26:40.256 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Content-Length: 6212544
12:26:40.256 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Server: GitHub.com
12:26:40.256 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Content-Type: application/octet-stream
12:26:40.256 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> permissions-policy: interest-cohort=()
12:26:40.256 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Last-Modified: Tue, 20 Dec 2022 16:26:05 GMT
12:26:40.303 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Access-Control-Allow-Origin: *
12:26:40.303 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> ETag: "63a1e21d-5ecbc0"
12:26:40.303 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> expires: Wed, 21 Dec 2022 06:51:01 GMT
12:26:40.303 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Cache-Control: max-age=600
12:26:40.303 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> x-proxy-cache: MISS
12:26:40.303 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> X-GitHub-Request-Id: 3DAC:0FF9:6B2D8:78F0F:63A2AA7D
12:26:40.303 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Accept-Ranges: bytes
12:26:40.350 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Age: 256
12:26:40.350 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Date: Wed, 21 Dec 2022 06:56:38 GMT
12:26:40.350 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Via: 1.1 varnish
12:26:40.350 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> X-Served-By: cache-bom4722-BOM
12:26:40.350 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> X-Cache: HIT
12:26:40.350 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> X-Cache-Hits: 0
12:26:40.350 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> X-Timer: S1671605799.542238,VS0,VE21
12:26:40.396 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> Vary: Accept-Encoding
12:26:40.396 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> X-Fastly-Request-ID: ca6e2cb676972177b1e9915af07016ea8abf60ce
12:26:40.396 -> [I] HttpHeader.h : 162 - HttpHeader::readLine -> 
12:26:40.396 -> [I] URLStream.h : 88 - size: 6212544
12:26:40.631 -> [I] AudioCopy.h : 76 - buffer_size=1024
12:26:51.928 -> [I] C:\Users\udays\AppData\Local\Temp\arduino_modified_sketch_207057\streams-url-file.ino : 54 - file size: 0

I noticed that in your log the 2nd last line has :

15:40:31.374 -> [I] sketch_dec20a.ino : 65 - file size: 6212544

Whereas in mine it is:

12:26:40.631 -> [I] AudioCopy.h : 76 - buffer_size=1024
12:26:51.928 -> [I] C:\Users\udays\AppData\Local\Temp\arduino_modified_sketch_207057\streams-url-file.ino : 54 - file size: 0

Could you tell me what 54 and 65 means.

[pschatzmann]

That's the line number in your sketch. Are you really sure that you have added the copier.setCheckAvailableForWrite(false); in your sketch ?

[Udaymakxenia]

I added the copier.setCheckAvailableForWrite(false) in the example and it worked. I am sorry as I got confused with what sketch you were asking me to check. Thank you for the quick help.

[Udaymakxenia]

Currently the example is working fine, but I wanted to put a timeout to connecting to the wifi network , is it possible to do that ?

[Udaymakxenia]

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  unsigned long oldTime = millis();
  while (WiFi.status() != WL_CONNECTED) {
    if (millis() - oldTime > 5000) {
      break;
    }
  }

I have used these lines of code before calling url.begin . It seems to be working but wanted to know if the same was possible using the library

[pschatzmann]

You can manage the Wifi connection yourself and then just omit the userid and password from the URLStream