app.py

import streamlit as st
import langcodes
from allosaurus.app import read_recognizer
from pathlib import Path
import string
from itertools import permutations
from collections import defaultdict
import torchaudio

@st.cache
def get_supported_codes():
  model = read_recognizer()  
  supported_codes = []
  supported_codes.append("ipa") # default option
  for combo in permutations(string.ascii_lowercase, r=3):
    code = "".join(combo)
    if model.is_available(code):
      supported_codes.append(code)
      
  
  return supported_codes
  
  
def get_path_to_wav_format(uploaded_file, suppress_outputs=False):
#  st.write(dir(uploaded_file))
#  st.write(type(uploaded_file))
#  st.write(uploaded_file)
  uploaded_bytes = uploaded_file.getvalue()
  actual_file_path = Path(uploaded_file.name)
  actual_file_path.write_bytes(uploaded_bytes)
    

  if ".wav" in uploaded_file.name:
    return Path(uploaded_file.name)
  if ".mp3" in uploaded_file.name:
    new_desired_path = actual_file_path.with_suffix(".wav")
    encoding="PCM_S" # Prevent encoding errors. https://stackoverflow.com/questions/60352850/wave-error-unknown-format-3-arises-when-trying-to-convert-a-wav-file-into-text
    bits_per_sample=16
    waveform, sample_rate = torchaudio.load(actual_file_path)
    if not suppress_outputs:
      st.info(f"Allosaurus requires .wav files. Converting with torchaudio, encoding={encoding}, bits_per_sample={bits_per_sample}")
      st.info(f"Uploaded file sample_rate: {sample_rate}")
    torchaudio.save(new_desired_path, waveform, sample_rate, 
                    encoding=encoding, 
                    bits_per_sample=bits_per_sample,
                    )

    return new_desired_path

@st.cache
def get_langcode_description(input_code, url=False):
  langcode = "ipa" # the default allosaurus recognizer
  description = "the default universal setting, not specific to any language"
  
  if not input_code or input_code==langcode:
    return description
    


  try:
    lang = langcodes.get(input_code)
    alpha3 = lang.to_alpha3()
    langcode = alpha3 
    display_name = lang.display_name()
    if url:
      description = f"[{display_name}](https://iso639-3.sil.org/code/{alpha3})"
    else:
      description = display_name 
    
  except langcodes.LanguageTagError as e:
    pass    
  return description

@st.cache    
def get_langcode_with_description(input_code):
  return f"{input_code}: {get_langcode_description(input_code)}"


if __name__ == "__main__":
#  input_code = st.text_input("(optional) 2 or 3-letter ISO code for input language. 2-letter codes will be converted to 3-letter codes", max_chars=3)
  supported_codes = get_supported_codes()
  index_of_desired_default = supported_codes.index("ipa")
  langcode = st.selectbox("ISO code for input language. Allosaurus doesn't need this, but it can improve accuracy", 
                          options=supported_codes, 
                          index=index_of_desired_default,
                          format_func=get_langcode_with_description
                          )
  
  model = read_recognizer()
  description = get_langcode_description(langcode, url=True)

  st.write(f"Instructing Allosaurus to recognize using language {langcode}. That is, {description}")

  
  uploaded_files = st.file_uploader("Choose a file", type=[
                                                          ".wav", 
                                                          ".mp3", 
                                                          ],
                                                    accept_multiple_files=True,
                                                          )
  
  results = {} # for better download/display
  
  uploaded_files_count = len(uploaded_files)
  suppress_output_threshold = 2
  my_bar = st.progress(0)
  for i, uploaded_file in enumerate(uploaded_files):
    
    if uploaded_file is not None:            
      wav_file = get_path_to_wav_format(uploaded_file, uploaded_files_count>suppress_output_threshold)    
      result = model.recognize(wav_file, langcode)
      results[uploaded_file.name] = result
    my_bar.progress(i+1/uploaded_files_count)
  st.write(results)