soundDownload.py

import os, sys
import freesound as fs
import json

descriptors = [ 'lowlevel.spectral_centroid.mean',
                'lowlevel.spectral_contrast.mean',
                'lowlevel.dissonance.mean',
                'lowlevel.hfc.mean',
                'lowlevel.mfcc.mean',
                'sfx.logattacktime.mean',
                'sfx.inharmonicity.mean']

def downloadSoundsFreesound(queryText = "", tag=None, duration=None, API_Key = "hjNYO8PPFWKuvcboJo9YEhtGRSv8TFwNsYY5LWVM", outputDir = "", topNResults = 5, featureExt = '.json'):
  """
  This function downloads sounds and their descriptors from freesound using the queryText and the 
  tag specified in the input. Additionally, you can also specify the duration range to filter sounds 
  based on duration.
  
  Inputs:
        (Input parameters marked with a * are optional)
        queryText (string): query text for the sounds (eg. "violin", "trumpet", "cello", "bassoon" etc.)
        tag* (string): tag to be used for filtering the searched sounds. (eg. "multisample",  
                       "single-note" etc.)
        duration* (tuple): min and the max duration (seconds) of the sound to filter, eg. (0.2,15)
        API_Key (string): your api key, which you can obtain from : www.freesound.org/apiv2/apply/
        outputDir (string): path to the directory where you want to store the sounds and their 
                            descriptors
        topNResults (integer): number of results(sounds) that you want to download 
        featureExt (string): file extension for storing sound descriptors
  output:
        This function downloads sounds and descriptors, and then stores them in outputDir. In 
        outputDir it creates a directory of the same name as that of the queryText. In this 
        directory outputDir/queryText it creates a directory for every sound with the name 
        of the directory as the sound id. Additionally, this function also dumps a text file 
        containing sound-ids and freesound links for all the downloaded sounds in the outputDir. 
        NOTE: If the directory outputDir/queryText exists, it deletes the existing contents 
        and stores only the sounds from the current query. 
  """ 
  
  # Checking for the compulsory input parameters
  if queryText == "":
    print("\n")
    print("Provide a query text to search for sounds")
    return -1
    
  if API_Key == "":
    print("\n")
    print("You need a valid freesound API key to be able to download sounds.")
    print("Please apply for one here: www.freesound.org/apiv2/apply/")
    print("\n")
    return -1
    
  if outputDir == "" or not os.path.exists(outputDir):
    print("\n")
    print("Please provide a valid output directory. This will be the root directory for storing sounds and descriptors")
    return -1    
  
  # Setting up the Freesound client and the authentication key
  fsClnt = fs.FreesoundClient()
  fsClnt.set_token(API_Key,"token")  
  
  # Creating a duration filter string that the Freesound API understands
  if duration and type(duration) == tuple:
    flt_dur = " duration:[" + str(duration[0])+ " TO " +str(duration[1]) + "]"
  else:
    flt_dur = ""
 
  if tag and type(tag) == str:
    flt_tag = "tag:"+tag
  else:
    flt_tag = ""

  # Querying Freesound
  page_size = 30
  if not flt_tag + flt_dur == "":
    qRes = fsClnt.text_search(query=queryText ,filter = flt_tag + flt_dur,sort="score", fields="id,name,previews,username,url,analysis", descriptors=','.join(descriptors), page_size=page_size, normalized=1)
  else:
    qRes = fsClnt.text_search(query=queryText ,sort="score",fields="id,name,previews,username,url,analysis", descriptors=','.join(descriptors), page_size=page_size, normalized=1)
  
  outDir2 = os.path.join(outputDir, queryText)
  if os.path.exists(outDir2):             # If the directory exists, it deletes it and starts fresh
      os.system("rm -r " + outDir2)
  os.mkdir(outDir2)

  pageNo = 1
  sndCnt = 0
  indCnt = 0
  totalSnds = min(qRes.count,200)   # System quits after trying to download after 200 times
  
  # Creating directories to store output and downloading sounds and their descriptors
  downloadedSounds = []
  while(1):
    if indCnt >= totalSnds:
      print("Not able to download required number of sounds. Either there are not enough search results on freesound for your search query and filtering constraints or something is wrong with this script.")
      break
    sound = qRes[indCnt - ((pageNo-1)*page_size)]
    print("Downloading mp3 preview and descriptors for sound with id: %s"%str(sound.id))
    outDir1 = os.path.join(outputDir, queryText, str(sound.id))
    if os.path.exists(outDir1):
      os.system("rm -r " + outDir1)
    os.system("mkdir " + outDir1)
    
    mp3Path = os.path.join(outDir1,  str(sound.previews.preview_lq_mp3.split("/")[-1]))
    ftrPath = mp3Path.replace('.mp3', featureExt)
    
    try:
      
      fs.FSRequest.retrieve(sound.previews.preview_hq_mp3, fsClnt, mp3Path)
      # Initialize a dictionary to store descriptors
      features = {}
      # Obtaining all the descriptors
      for desc in descriptors:
        features[desc]=[]
        features[desc].append(eval("sound.analysis."+desc))
      
      # Once we have all the descriptors, store them in a json file
      json.dump(features, open(ftrPath,'w'))
      sndCnt+=1
      downloadedSounds.append([str(sound.id), sound.url])

    except:
      if os.path.exists(outDir1):
        os.system("rm -r " + outDir1)
    
    indCnt +=1
    
    if indCnt%page_size==0:
      qRes = qRes.next_page()
      pageNo+=1
      
    if sndCnt>=topNResults:
      break
  # Dump the list of files and Freesound links
  fid = open(os.path.join(outDir2, queryText+'_SoundList.txt'), 'w')
  for elem in downloadedSounds:
    fid.write('\t'.join(elem)+'\n')
  fid.close()