• Journal of information and communication convergence engineering
• /
• 제7권4호
• /
• pp.535-538
• /
• 2009

Speckle noise reduction for ultrasound CT image using morphological adaptive median filtering based on edge preservation is presented in this paper. Speckle noise is multiplicative feature and causes ultrasound image to degrade widely from transducer. An input image is classified into edge region and homogeneous region in preprocessing. The speckle is reduced by morphological operation on the 2D gray scale by using convolution and correlation, and edges are preserved. The adaptive median is processed to reduce an impulse noise to preserve edges. As the result, MAM of the proposed method enhances the image to about 10% in comparison with Winner filter by Edge Preservation Index and PSNR, and 10% to only adaptive median filtering.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2009년도 추계학술대회
• /
• pp.329-332
• /
• 2009

Speckle noise reduction for ultrasound CT image using morphological adaptive median filtering based on edge preservation is presented in this paper. Speckle noise is multiplicative feature and causes ultrasound image to degrade widely from transducer. An input image is classified into edge region and homogeneous region in preprocessing. The speckle is reduced by morphological operation on the 2D gray scale by using convolution and correlation, and edges are preserved. The adaptive median is processed to reduce an impulse noise. As the result the proposed method enhances the image to about 20% in comparison with Winer filter by Edge Preservation Index and PSNR.

• 한국멀티미디어학회논문지
• /
• 제7권4호
• /
• pp.467-473
• /
• 2004

비디오내에서의 자막은 비디오 내용을 전달하는 중요한 역할을 수행한다. 기존의 자막 영 역 추출방법들은 잡음에 민감하여 배경에서 자막 영역의 추출이 어려웠다. 본 논문에서는 다중 프레임 병합과 영역 최소 사각형을 이용하여 스포츠 비디오에서 자막 영역을 추출하는 방법을 제안한다. 전처리과정으로서 명암 대비 스트래칭과 Othu Method를 이용하여 적응적 임계치를 추출할 수 있다. 다중 프레임 병합에 의하여 자막 프레임 구간을 추출하고, 자막 영역은 미디언 필터링, 형태학적 불림, 영역 레이블링, 후보 문자영역 필터링, 영역 최소 사각형 검출에 의하여 효율적으로 추출된다.