Identificação de áreas cultivadas com café por meio de descritores texturais

• Autor(a) principal: Silveira, Lucas Silva da
• Data de Publicação: 2013
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3657
• topic: Áreas cultivadas; Café; Descritores texturais; Cultivated areas; Coffee; Textural descriptors; CNPQ::CIENCIAS AGRARIAS::ENGENHARIA AGRICOLA

The importance of coffee agriculture in Brazil is notorious, especially for the State of Minas Gerais, which is the Brazilian state that accounts for most of the national production. In the Southern region and in Zona da Mata they are concentrated most of the crops of the State; also, small holdings are predominant in the region and cultivation is done in mountain region, what makes it difficult mapping the crops by automated methods. The application of Artificial Neural Networks (ANNs), having as input variables Haralick s descriptors, has shown a promising approach for the discrimination of higher complexity classes. In this context, it aimed to develop a system to identify areas where coffee is cultivated using ANNs, having as input variables Haralick s descriptors. The studied area is located at the city of Araponga, where 59 fields were selected with coffee plantations for data collection. The software used for processing and sorting the images was MATLAB; and for evaluating the sorting performance, Arcgis was used. The methodology for the development of ANN consisted in two steps: in the first step, the ANN was trained with representative samples of each class of interest (coffee, forest, water, bare soil, and grassland, and urban area), thus verifying the potential to discriminate output classes; in the second step the objective was to classify the coffee plantations accordingly with the age. Kappa index was used for evaluating the performance of ANN; the usage of this coefficient is satisfactory for assessing the accuracy of a thematic class. Kappa index for discriminating the coffee region of the other class of interest was 65,18%, what can be considered a good index. To classify the coffee plantations accordingly with the age, Kappa index was variable (0.675 to 0.4783), being very good for the Itatiaia farm and reasonable to the Pedra Redonda farm.