3 research outputs found
SegNema: Nematode segmentation strategy in digital microscopy images using deep learning and shape models
Proyecto de Graduación (MaestrÃa en Computación con énfasis en Ciencias de la Computación) Instituto Tecnológico de Costa Rica, Escuela de IngenierÃa en Computación, 2019.Nematodes are the most numerous multicellular animals on Earth and their study has a
direct impact in the improvement and development of agricultural activities. This document
introduces SegNema, a strategy for the segmentation of nematodes in microscopy
images where deep learning is used for classification of pixels as nematode or background,
and a shape model is used to associate landmarks that describe the position of the nematode
in the image.
To train the segmentation model, a set of 2939 manually labeled uncompressed images of
size 1024 ⇥ 768 pixels obtained from 13 di↵erent sequences of microscopy images is used.
The landmarks that describe the position of the nematodes in these training images are
used to adjust a model capable of representing shapes corresponding to a nematode. The
disparity between the shapes of the regions classified as nematode in the segmentation
stage and their possible truncated representation with the shape model is used to rule
out possible erroneous classifications. The validation of this model was performed on 321
images of the microscopy sequences that were not used in the training stage.
In each image used for training and validation, there is information on the position of
landmarks where a single nematode is delimited although more nematodes may be present.Los nematodos son los animales pluricelulares más numerosos en la Tierra y su estudio
tiene un impacto en el desarrollo de actividades agrÃcolas. En este documento se introduce
SegNema, una estrategia para la segmentación de nematodos en imágenes de microscopia
donde se utiliza aprendizaje profundo para clasificación de pÃxeles como nematodo o
fondo, y modelos de forma para asociar hitos que describen la posición del nematodo en
la imagen.
Para entrenar el modelo de segmentación se usan 2939 imágenes sin comprimir etiquetadas
manualmente de tamaño 1024 ⇥ 768 p´ıxeles obtenidas de 13 secuencias de imágenes de
microscopia. Por otro lado, los hitos que describen la posición de los nematodos en estas
imágenes de entrenamiento son utilizados para ajustar un modelo capaz de representar
formas correspondientes a nematodo. La disparidad entre formas de las regiones clasificadas
como nematodo en la etapa de segmentación y su posible representación truncada
con el modelo de forma es usado para descartar posibles clasificaciones err´oneas. Para la
validación de este modelo se usan 321 imágenes de las secuencias de microscopia que no
son utilizadas en la etapa de entrenamiento.
En cada imagen usada para entrenamiento y validación existe la información de la posici´on
de hitos donde se delimita un único nematodo aunque otros nematodos pueden estar
presentes
Detection of root knot nematodes in microscopy images
Object detection in microscopy image is essential for further analysis in many applications. However, images are not always easy to analyze due to uneven illumination and noise. In addition, objects may appear merged together with debris. This work presents a method for detecting rice root knot nematodes in microscopy images. The problem involves four subproblems which are dealt with separately. The uneven illumination is corrected via polynomial fitting. The nematodes are then highlighted using mathematical morphology. A binary image is obtained and the microscope lines are removed. Finally, the detected nematodes are counted after thresholding the non-nematode particles. The results obtained from the performed tests show that this is a reliable and effective method when compared to manual counting