Data/hora: 06/06/2024 08:38:33

Provedor de dados: 	5	
País: 	France	
Título: 	Frequency demodulation on otolith numerical images for the automation of fish age estimation	
Autores: 	Troadec, Herve.	
Data: 	1991-10	
Ano: 	1991	
Palavras-chave: 	Otolithe; Image numérique; Âge; Croissance; Solea solea / Pollachius virens; Otolith; Digital image; Age; Growth; Solea solea / Pollachius virens.	
Resumo: 	A method to assist the reading of calcified structures with digital images is proposed. An a priori growth pattern is introduced in the image processing to take into account both the variability of the ring size and the non-linearity of their growth. The introduction of biological knowledge is performed within a demodulation processing using the reciprocal growth function. The ring number is estimated by spectral analysis. The constraints introduced by the growth model are weak since they are restricted to the definition of L0, in the case of an exponential model, or of L∞ in the case of a Von Bertalanffy model. When applied to larval Dover sole otoliths (Solea solea) results close to the expert's are obtained. In the case of saithe otoliths (Pollachius virens) the mean discrepancy with the expert's, i.e. 1.5 years, can be assigned to the lack of processing of marginal rings and to the inadequacy of the morphogenesis model on which the processing algorithm is based. This approach which is only founded on the dynamic features of the "biological signal", will have to be completed in future work with the introduction of structural information.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	http://archimer.ifremer.fr/doc/00189/30072/28560.pdf

DOI:10.1051/alr:1991022	
Editor: 	EDP Sciences	
Relação: 	http://archimer.ifremer.fr/doc/00189/30072/	
Formato: 	application/pdf	
Fonte: 	Aquatic Living Resources (0990-7440) (EDP Sciences), 1991-10 , Vol. 4 , N. 4 , P. 207-219	
Fonte: 	IFREMER-Gauthier-Villars, 1991