Phonetics and Speech Sciences (말소리와 음성과학)

Korean Society of Speech Sciences (한국음성학회)
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A comparative analysis of metadata structures and attributes of Samsung smartphone voice recording files for forensic use

법과학적 활용을 위한 삼성 스마트폰 음성 녹음 파일의 메타데이터 구조 및 속성 비교 분석 연구

  • Ahn, Seo-Yeong (Department of Future Convergence Technology Engineering, Sungshin Women's University) ;
  • Ryu, Se-Hui (Department of Future Convergence Technology Engineering, Sungshin Women's University) ;
  • Kim, Kyung-Wha (Forensic Science Division, Supreme Prosecutor's Office) ;
  • Hong, Ki-Hyung (Department of Service Design Engineering, Sungshin Women's University)
  • 안서영 (성신여자대학교 미래융합기술공학과) ;
  • 유세희 (성신여자대학교 미래융합기술공학과) ;
  • 김경화 (대검찰청 과학수사부) ;
  • 홍기형 (성신여자대학교 서비스디자인공학과)
  • Received : 2022.08.19
  • Accepted : 2022.09.15
  • Published : 2022.09.30
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Abstract

Due to the popularization of smartphones, most of the recorded speech files submitted as evidence of recent crimes are produced by smartphones, and the integrity (forgery) of the submitted speech files based on smartphones is emerging as a major issue in the investigation and trial process. Samsung smartphones with the highest domestic market share are distributed with built-in speech recording applications that can record calls and voice, and can edit recorded speech. Unlike editing through third-party speech (audio) applications, editing by their own builtin speech applications has a high similarity to the original file in metadata structures and attributes, so more precise analysis techniques need to prove integrity. In this study, we constructed a speech file metadata database for speech files (original files) recorded by 34 Samsung smartphones and edited speech files edited by their built-in speech recording applications. We analyzed by comparing the metadata structures and attributes of the original files to their edited ones. As a result, we found significant metadata differences between the original speech files and the edited ones.

스마트폰의 대중화로 인하여 근래 범죄의 증거자료로 제출되는 녹취 파일은 대부분 스마트폰을 통하여 생산되고 있으며, 스마트폰을 기반으로 한 녹음 파일의 무결성(위변조) 여부가 수사와 재판 과정에서 주요 쟁점으로 떠오르고 있다. 가장 높은 국내 시장 점유율을 가진 삼성 스마트폰은 통화 및 음성 녹음, 그리고 편집이 가능한 자체 음성녹음 편집 어플리케이션이 탑재되어 유통되고 있으며, 자체 어플리케이션을 통한 편집은 외부 어플리케이션을 통한 편집과 다르게 원본 파일과의 유사성이 높기에, 무결성을 입증하기 위해 더 정밀한 분석 기법 개발이 필요하다. 본 연구에서는 삼성 스마트폰 34개 기종에서 생성된 원본 녹음 파일과 자체 제공 음성녹음 편집 어플리케이션을 통한 편집 파일의 메타데이터 구조와 속성을 분석하여, 원본과 편집본 사이의 음성 파일 메타데이터 구조 및 속성 값에서 유의미한 차이가 있음을 확인하였다.

Keywords

Acknowledgement

이 논문은 2021년 대검찰청 연구 용역의 지원으로 수행되었습니다(과제명: 스마트폰 녹음 파일의 위변조 여부 분석 기법 개발).

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