Abstract  Environment  recognition  from  digital  audio  for  fore nsics  application  is  a  growing  area  of  interest.  However,  compared  to  other  branches  of  audio  forensics,  it  i s  a  less  researched  one.  Especially  less  attention has  been  given  to  detect  environment  from  files  where  foreground  speech  is  p resent,  which  is  a  forensics  scenario.  In  this  paper,  we  perform  several  experiments  focusing  on  the  problems  of  environment   recognition  from  audio  particularly  for  forensics application.  Experimental  results  show  that  the  task  is  easier  w hen  audio  files  contain  only  environmental  sound  th an  when  they  contain  both  foreground  speech  and  background  environment.  We  propose  a  full  set  of  MPEG-7  audio  features  comb ined  with  Mel  Frequency  Cepstral  Coefficients  (MFCCs)  to  improve  the  accuracy.  In  the  experiments,  the  proposed  approach  significantly  increases the recognition accuracy of environment s ound even in the presence of high amount of foregro und human speech.   

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