def main(_):
"""Brain tissue segmentation using decision forests.
The main routine executes the medical image analysis pipeline:
- Image loading
- Registration
- Pre-processing
- Feature extraction
- Decision forest classifier model building
- Segmentation using the decision forest classifier model on unseen images
- Post-processing of the segmentation
- Evaluation of the segmentation
"""
# load atlas images
putil.load_atlas_images(FLAGS.data_atlas_dir)
print('-' * 5, 'Training...')
# generate a model directory (use datetime to ensure that the directory is empty)
# we need an empty directory because TensorFlow will continue training an existing model if it is not empty
t = datetime.datetime.now().strftime('%Y-%m-%d%H%M%S')
model_dir = os.path.join(FLAGS.model_dir, t)
os.makedirs(model_dir, exist_ok=True)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_train_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
train_data_size = len(data_items)
pre_process_params = {
'zscore_pre': True,
'coordinates_feature': True,
'intensity_feature': True,
'gradient_intensity_feature': True
}
# initialize decision forest parameters
df_params = df.DecisionForestParameters()
df_params.num_classes = 4
df_params.num_trees = 160
df_params.max_nodes = 3000
df_params.model_dir = model_dir
forest = None
start_time_total_train = timeit.default_timer()
for batch_index in range(0, len(data_items), TRAIN_BATCH_SIZE):
cache_file_prefix = os.path.normpath(
os.path.join(
script_dir, './mia-cache/batch-' + str(batch_index) + '-' +
str(TRAIN_BATCH_SIZE)))
cache_file_train = cache_file_prefix + '-data_train.npy'
cache_file_labels = cache_file_prefix + '-data_labels.npy'
if (USE_PREPROCESS_CACHE & os.path.exists(cache_file_train)):
print('Using cache from ', cache_file_train)
data_train = np.load(cache_file_train)
labels_train = np.load(cache_file_labels)
else:
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TRAIN_BATCH_SIZE])
# load images for training and pre-process
images = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
print('pre-processing done')
# generate feature matrix and label vector
data_train = np.concatenate(
[img.feature_matrix[0] for img in images])
labels_train = np.concatenate(
[img.feature_matrix[1] for img in images])
if NORMALIZE_FEATURES:
# normalize data (mean 0, std 1)
# data_train = scipy_stats.zscore(data_train)
non_coord = scipy_stats.zscore(data_train[:, 3:8])
coord = data_train[:, 0:3] / 255 * 2 - 1
data_train = np.concatenate((coord, non_coord), axis=1)
if (USE_PREPROCESS_CACHE):
print('Writing cache')
if (not os.path.exists(os.path.dirname(cache_file_prefix))):
os.mkdir(os.path.dirname(cache_file_prefix))
data_train.dump(cache_file_train)
labels_train.dump(cache_file_labels)
if forest is None:
df_params.num_features = data_train.shape[1]
print(df_params)
forest = df.DecisionForest(df_params)
start_time = timeit.default_timer()
forest.train(data_train, labels_train)
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
time_total_train = timeit.default_timer() - start_time_total_train
start_time_total_test = timeit.default_timer()
print('-' * 5, 'Testing...')
result_dir = os.path.join(FLAGS.result_dir, t)
os.makedirs(result_dir, exist_ok=True)
# initialize evaluator
evaluator = putil.init_evaluator(result_dir)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_test_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
all_probabilities = None
for batch_index in range(0, len(data_items), TEST_BATCH_SIZE):
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TEST_BATCH_SIZE])
# load images for testing and pre-process
pre_process_params['training'] = False
images_test = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
images_prediction = []
images_probabilities = []
for img in images_test:
print('-' * 10, 'Testing', img.id_)
start_time = timeit.default_timer()
features = img.feature_matrix[0]
if NORMALIZE_FEATURES:
# features = scipy_stats.zscore(features)
non_coord = scipy_stats.zscore(features[:, 3:8])
coord = features[:, 0:3] / 255 * 2 - 1
features = np.concatenate((coord, non_coord), axis=1)
probabilities, predictions = forest.predict(features)
if all_probabilities is None:
all_probabilities = np.array([probabilities])
else:
all_probabilities = np.concatenate(
(all_probabilities, [probabilities]), axis=0)
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
# convert prediction and probabilities back to SimpleITK images
image_prediction = conversion.NumpySimpleITKImageBridge.convert(
predictions.astype(np.uint8), img.image_properties)
image_probabilities = conversion.NumpySimpleITKImageBridge.convert(
probabilities, img.image_properties)
# evaluate segmentation without post-processing
evaluator.evaluate(
image_prediction,
img.images[structure.BrainImageTypes.GroundTruth], img.id_)
images_prediction.append(image_prediction)
images_probabilities.append(image_probabilities)
# post-process segmentation and evaluate with post-processing
post_process_params = {'crf_post': True}
images_post_processed = putil.post_process_batch(images_test,
images_prediction,
images_probabilities,
post_process_params,
multi_process=True)
for i, img in enumerate(images_test):
evaluator.evaluate(
images_post_processed[i],
img.images[structure.BrainImageTypes.GroundTruth],
img.id_ + '-PP')
# save results
sitk.WriteImage(
images_prediction[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG.mha'),
True)
sitk.WriteImage(
images_post_processed[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG-PP.mha'),
True)
time_total_test = timeit.default_timer() - start_time_total_test
# write summary of parameters to results dir
with open(os.path.join(result_dir, 'summary.txt'), 'w') as summary_file:
print('Result dir: {}'.format(result_dir))
print('Result dir: {}'.format(result_dir), file=summary_file)
print('Training data size: {}'.format(train_data_size),
file=summary_file)
print('Total training time: {:.1f}s'.format(time_total_train),
file=summary_file)
print('Total testing time: {:.1f}s'.format(time_total_test),
file=summary_file)
print('Voxel Filter Mask: {}'.format(
putil.FeatureExtractor.VOXEL_MASK_FLT),
file=summary_file)
print('Normalize Features: {}'.format(NORMALIZE_FEATURES),
file=summary_file)
print('Decision forest', file=summary_file)
print(df_params, file=summary_file)
stats = statistics.gather_statistics(
os.path.join(result_dir, 'results.csv'))
print('Result statistics:', file=summary_file)
print(stats, file=summary_file)
def main(FLAGS,trees,nodes):
"""Brain tissue segmentation using decision forests.
The main routine executes the medical image analysis pipeline:
- Image loading
- Registration
- Pre-processing
- Feature extraction
- Decision forest classifier model building
- Segmentation using the decision forest classifier model on unseen images
- Post-processing of the segmentation
- Evaluation of the segmentation
"""
# load atlas images
putil.load_atlas_images(FLAGS.data_atlas_dir)
print('-' * 5, 'Training...')
# generate a model directory (use datetime to ensure that the directory is empty)
# we need an empty directory because TensorFlow will continue training an existing model if it is not empty
t = datetime.datetime.now().strftime('%Y-%m-%d%H%M%S')
t='DF_trees_'+str(trees)+'_nodes_'+str(nodes)
model_dir = os.path.join(FLAGS.model_dir, t)
os.makedirs(model_dir, exist_ok=True)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_train_dir,
IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
pre_process_params = {'zscore_pre': True,
'coordinates_feature': True,
'intensity_feature': True,
'gradient_intensity_feature': True}
# initialize decision forest parameters
df_params = df.DecisionForestParameters()
df_params.num_classes = 4
df_params.num_trees = trees
df_params.max_nodes = nodes
df_params.model_dir = model_dir
forest = None
start_time_total_train = timeit.default_timer()
for batch_index in range(0, len(data_items), TRAIN_BATCH_SIZE):
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index: batch_index+TRAIN_BATCH_SIZE])
# load images for training and pre-process
images = putil.pre_process_batch(batch_data, pre_process_params, multi_process=True)
print('pre-processing done')
# generate feature matrix and label vector
data_train = np.concatenate([img.feature_matrix[0] for img in images])
labels_train = np.concatenate([img.feature_matrix[1] for img in images])
if forest is None:
df_params.num_features = data_train.shape[1]
print(df_params)
forest = df.DecisionForest(df_params)
start_time = timeit.default_timer()
forest.train(data_train, labels_train)
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
time_total_train = timeit.default_timer() - start_time_total_train
print('-' * 5, 'Testing...')
result_dir = os.path.join(FLAGS.result_dir, t)
os.makedirs(result_dir, exist_ok=True)
# initialize evaluator
evaluator = putil.init_evaluator(result_dir)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_test_dir,
IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
for batch_index in range(0, len(data_items), TEST_BATCH_SIZE):
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index: batch_index + TEST_BATCH_SIZE])
# load images for testing and pre-process
pre_process_params['training'] = False
images_test = putil.pre_process_batch(batch_data, pre_process_params, multi_process=True)
images_prediction = []
images_probabilities = []
for img in images_test:
print('-' * 10, 'Testing', img.id_)
start_time = timeit.default_timer()
probabilities, predictions = forest.predict(img.feature_matrix[0])
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
# convert prediction and probabilities back to SimpleITK images
image_prediction = conversion.NumpySimpleITKImageBridge.convert(predictions.astype(np.uint8),
img.image_properties)
image_probabilities = conversion.NumpySimpleITKImageBridge.convert(probabilities, img.image_properties)
# evaluate segmentation without post-processing
evaluator.evaluate(image_prediction, img.images[structure.BrainImageTypes.GroundTruth], img.id_)
images_prediction.append(image_prediction)
images_probabilities.append(image_probabilities)
# post-process segmentation and evaluate with post-processing
post_process_params = {'crf_post': True}
images_post_processed = putil.post_process_batch(images_test, images_prediction, images_probabilities,
post_process_params, multi_process=True)
for i, img in enumerate(images_test):
evaluator.evaluate(images_post_processed[i], img.images[structure.BrainImageTypes.GroundTruth],
img.id_ + '-PP')
# save results
sitk.WriteImage(images_prediction[i], os.path.join(result_dir, images_test[i].id_ + '_SEG.mha'), True)
sitk.WriteImage(images_post_processed[i], os.path.join(result_dir, images_test[i].id_ + '_SEG-PP.mha'), True)
# write summary of parameters to results dir
with open(os.path.join(result_dir, 'summary.txt'), 'w') as summary_file:
print('Training data size: {}'.format(len(data_items)), file=summary_file)
print('Total training time: {:.1f}s'.format(time_total_train), file=summary_file)
print('Decision forest', file=summary_file)
print(df_params, file=summary_file)
stats = statistics.gather_statistics(os.path.join(result_dir, 'results.csv'))
print('Result statistics:', file=summary_file)
print(stats, file=summary_file)
def main(_):
"""Ensemble using results from various algorithms
"""
# load results from various previous runs
all_probabilities = None
for r in RESULTS:
p = np.load(os.path.join(r, 'all_probabilities.npy'))
if all_probabilities is None:
all_probabilities = p
else:
if p.shape != all_probabilities.shape:
print('Error: all_probabilities.npy do not match: ' +
str(p.shape) + ' vs. ' + str(all_probabilities.shape) +
' for ' + r)
sys.exit(1)
if ENSEMBLE_MAX:
all_probabilities = np.maximum(all_probabilities, p)
else:
all_probabilities = all_probabilities + p
if ENSEMBLE_MAX == False:
all_probabilities = all_probabilities / len(r)
# convert back to float32
all_probabilities = all_probabilities.astype(np.float32)
# load atlas images
putil.load_atlas_images(FLAGS.data_atlas_dir)
pre_process_params = {
'zscore_pre': True,
'coordinates_feature': True,
'intensity_feature': True,
'gradient_intensity_feature': True
}
t = datetime.datetime.now().strftime('%Y-%m-%d%H%M%S')
print('-' * 5, 'Testing...')
result_dir = os.path.join(FLAGS.result_dir, t)
os.makedirs(result_dir, exist_ok=True)
# initialize evaluator
evaluator = putil.init_evaluator(result_dir)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_test_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
index = 0
for batch_index in range(0, len(data_items), TEST_BATCH_SIZE):
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TEST_BATCH_SIZE])
# load images for testing and pre-process
pre_process_params['training'] = False
images_test = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
images_prediction = []
images_probabilities = []
for img in images_test:
print('-' * 10, 'Testing', img.id_)
start_time = timeit.default_timer()
probabilities = all_probabilities[index, :, :]
index = index + 1
predictions = LABEL_CLASSES[probabilities.argmax(axis=1)]
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
# convert prediction and probabilities back to SimpleITK images
image_prediction = conversion.NumpySimpleITKImageBridge.convert(
predictions.astype(np.uint8), img.image_properties)
image_probabilities = conversion.NumpySimpleITKImageBridge.convert(
probabilities, img.image_properties)
# evaluate segmentation without post-processing
evaluator.evaluate(
image_prediction,
img.images[structure.BrainImageTypes.GroundTruth], img.id_)
images_prediction.append(image_prediction)
images_probabilities.append(image_probabilities)
# post-process segmentation and evaluate with post-processing
post_process_params = {'crf_post': True}
images_post_processed = putil.post_process_batch(images_test,
images_prediction,
images_probabilities,
post_process_params,
multi_process=True)
for i, img in enumerate(images_test):
evaluator.evaluate(
images_post_processed[i],
img.images[structure.BrainImageTypes.GroundTruth],
img.id_ + '-PP')
# save results
sitk.WriteImage(
images_prediction[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG.mha'),
True)
sitk.WriteImage(
images_post_processed[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG-PP.mha'),
True)
# write summary of parameters to results dir
with open(os.path.join(result_dir, 'summary.txt'), 'w') as summary_file:
print('Result dir: {}'.format(result_dir))
print('Result dir: {}'.format(result_dir), file=summary_file)
print('Ensemble from ' + str(RESULTS), file=summary_file)
print('ENSEMBLE_MAX ' + str(ENSEMBLE_MAX), file=summary_file)
stats = statistics.gather_statistics(
os.path.join(result_dir, 'results.csv'))
print('Result statistics:', file=summary_file)
print(stats, file=summary_file)
def main(_):
"""Brain tissue segmentation using decision forests.
The main routine executes the medical image analysis pipeline:
- Image loading
- Registration
- Pre-processing
- Feature extraction
- Decision forest classifier model building
- Segmentation using the decision forest classifier model on unseen images
- Post-processing of the segmentation
- Evaluation of the segmentation
"""
# load atlas images
putil.load_atlas_images(FLAGS.data_atlas_dir)
print('-' * 5, 'Training...')
# generate a model directory (use datetime to ensure that the directory is empty)
# we need an empty directory because TensorFlow will continue training an existing model if it is not empty
t = datetime.datetime.now().strftime('%Y-%m-%d%H%M%S')
model_dir = os.path.join(FLAGS.model_dir, t)
os.makedirs(model_dir, exist_ok=True)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_train_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
train_data_size = len(data_items)
pre_process_params = {
'zscore_pre': True, #1 features
'coordinates_feature': False, #3 features
'intensity_feature': True, #1 features
'gradient_intensity_feature': True
} #2 features
start_time_total_train = timeit.default_timer()
n_neighbors = 20
batch_data = dict(data_items)
# load images for training and pre-process
images = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
print('pre-processing done')
# generate feature matrix and label vector
data_train = np.concatenate([img.feature_matrix[0] for img in images])
labels_train = np.concatenate([img.feature_matrix[1] for img in images])
if NORMALIZE_FEATURES:
# normalize data (mean 0, std 1)
data_train = scipy_stats.zscore(data_train)
start_time = timeit.default_timer()
neigh = KNeighborsClassifier(n_neighbors=n_neighbors,
weights='distance',
algorithm='auto').fit(data_train,
labels_train[:, 0])
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
time_total_train = timeit.default_timer() - start_time_total_train
start_time_total_test = timeit.default_timer()
print('-' * 5, 'Testing...')
result_dir = os.path.join(FLAGS.result_dir, t)
os.makedirs(result_dir, exist_ok=True)
# initialize evaluator
evaluator = putil.init_evaluator(result_dir)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_test_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
all_probabilities = None
for batch_index in range(0, len(data_items), TEST_BATCH_SIZE):
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TEST_BATCH_SIZE])
# load images for testing and pre-process
pre_process_params['training'] = False
images_test = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
images_prediction = []
images_probabilities = []
for img in images_test:
print('-' * 10, 'Testing', img.id_)
start_time = timeit.default_timer()
# probabilities, predictions = forest.predict(img.feature_matrix[0])
features = img.feature_matrix[0]
if NORMALIZE_FEATURES:
features = scipy_stats.zscore(features)
predictions = neigh.predict(features)
probabilities = neigh.predict_proba(features)
if all_probabilities is None:
all_probabilities = np.array([probabilities])
else:
all_probabilities = np.concatenate(
(all_probabilities, [probabilities]), axis=0)
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
# convert prediction and probabilities back to SimpleITK images
image_prediction = conversion.NumpySimpleITKImageBridge.convert(
predictions.astype(np.uint8), img.image_properties)
image_probabilities = conversion.NumpySimpleITKImageBridge.convert(
probabilities, img.image_properties)
# evaluate segmentation without post-processing
evaluator.evaluate(
image_prediction,
img.images[structure.BrainImageTypes.GroundTruth], img.id_)
images_prediction.append(image_prediction)
images_probabilities.append(image_probabilities)
# post-process segmentation and evaluate with post-processing
post_process_params = {'crf_post': True}
images_post_processed = putil.post_process_batch(images_test,
images_prediction,
images_probabilities,
post_process_params,
multi_process=True)
for i, img in enumerate(images_test):
evaluator.evaluate(
images_post_processed[i],
img.images[structure.BrainImageTypes.GroundTruth],
img.id_ + '-PP')
# save results
sitk.WriteImage(
images_prediction[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG.mha'),
True)
sitk.WriteImage(
images_post_processed[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG-PP.mha'),
True)
time_total_test = timeit.default_timer() - start_time_total_test
# write summary of parameters to results dir
with open(os.path.join(result_dir, 'summary.txt'), 'w') as summary_file:
print('Result dir: {}'.format(result_dir))
print('Result dir: {}'.format(result_dir), file=summary_file)
print('Training data size: {}'.format(train_data_size),
file=summary_file)
print('Total training time: {:.1f}s'.format(time_total_train),
file=summary_file)
print('Total testing time: {:.1f}s'.format(time_total_test),
file=summary_file)
print('Voxel Filter Mask: {}'.format(
putil.FeatureExtractor.VOXEL_MASK_FLT),
file=summary_file)
print('Normalize Features: {}'.format(NORMALIZE_FEATURES),
file=summary_file)
print('kNN', file=summary_file)
print('n_neighbors: {}'.format(n_neighbors), file=summary_file)
stats = statistics.gather_statistics(
os.path.join(result_dir, 'results.csv'))
print('Result statistics:', file=summary_file)
print(stats, file=summary_file)
def main(_):
"""Brain tissue segmentation using SVM.
The main routine executes the medical image analysis pipeline:
- Image loading
- Registration
- Pre-processing
- Feature extraction
- SVM model building
- Segmentation using the decision forest classifier model on unseen images
- Post-processing of the segmentation
- Evaluation of the segmentation
"""
# SVM cannot deal with default mark (too much data). Reduce by factor 10
putil.FeatureExtractor.VOXEL_MASK_FLT = [0.00003, 0.0004, 0.0003, 0.0004]
# load atlas images
putil.load_atlas_images(FLAGS.data_atlas_dir)
print('-' * 5, 'Training...')
# generate a model directory (use datetime to ensure that the directory is empty)
# we need an empty directory because TensorFlow will continue training an existing model if it is not empty
t = datetime.datetime.now().strftime('%Y-%m-%d%H%M%S')
model_dir = os.path.join(FLAGS.model_dir, t)
os.makedirs(model_dir, exist_ok=True)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_train_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
train_data_size = len(data_items)
pre_process_params = {
'zscore_pre': True,
'coordinates_feature': True,
'intensity_feature': True,
'gradient_intensity_feature': True
}
start_time_total_train = timeit.default_timer()
batch_data = dict(data_items)
# load images for training and pre-process
images = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
print('pre-processing done')
# generate feature matrix and label vector
data_train = np.concatenate([img.feature_matrix[0] for img in images])
labels_train = np.concatenate([img.feature_matrix[1] for img in images])
if NORMALIZE_FEATURES:
# normalize data (mean 0, std 1)
data_train = scipy_stats.zscore(data_train)
print('Start training SVM')
# Training
# SVM does not support online/incremental training. Need to fit all in one go!
# Note: Very slow with large training set!
start_time = timeit.default_timer()
# to limite: max_iter=1000000000
# Enable for grid search of best hyperparameters
if False:
C_range = [300, 350, 400, 450, 500, 550, 600, 800, 1000, 1200, 1500]
gamma_range = [
0.00001, 0.00003, 0.00004, 0.00005, 0.00006, 0.00008, 0.0001,
0.0005, 0.001, 0.005, 0.01, 0.1, 0.2
]
# 1
C_range = [
0.001, 0.01, 0.1, 0.5, 1, 3, 5, 10, 20, 50, 100, 200, 250, 300,
1000, 2000, 5000, 10000, 20000, 50000, 100000, 120000, 150000
]
gamma_range = [
0.0000001, 0.000001, 0.00001, 0.00005, 0.0001, 0.0005, 0.001,
0.005, 0.01, 0.1, 0.2, 0.5, 1, 5, 10
]
#C_range = [1, 10, 100, 500, 1000, 5000, 10000, 15000, 20000, 22000, 25000, 30000, 35000]
#gamma_range = [0.00000001, 0.0000001, 0.000001, 0.00001, 0.00005, 0.0001, 0.0005, 0.001, 0.005, 0.01, 0.1, 0.2, 0.5]
params = [{
'kernel': ['rbf'],
'C': C_range,
'gamma': gamma_range,
}]
#'C': [0.001, 0.01, 0.1, 0.5, 1, 3, 5, 10, 20, 50, 100, 200, 250, 300, 1000],
#'gamma': [0.00001, 0.00005, 0.0001, 0.0005, 0.001, 0.005, 0.01, 0.1, 0.2, 0.5, 1, 5, 10, 20, 100, 10
clf = GridSearchCV(SVC(probability=True, cache_size=2000),
params,
cv=2,
n_jobs=8,
verbose=3)
clf.fit(data_train, labels_train[:, 0])
print('best param: ' + str(clf.best_params_))
scores = clf.cv_results_['mean_test_score'].reshape(
len(C_range), len(gamma_range))
plt.figure(figsize=(8, 6))
plt.subplots_adjust(left=.2, right=0.95, bottom=0.15, top=0.95)
plt.imshow(scores,
interpolation='nearest',
cmap=plt.cm.hot,
norm=MidpointNormalize(vmin=0.2, midpoint=0.92))
plt.xlabel('gamma')
plt.ylabel('C')
plt.colorbar()
plt.xticks(np.arange(len(gamma_range)), gamma_range, rotation=45)
plt.yticks(np.arange(len(C_range)), C_range)
plt.title('Validation accuracy')
plt.savefig('svm_params.png')
#plt.show()
scipy.io.savemat('svm_params.mat',
mdict={
'C': C_range,
'gamma': gamma_range,
'score': scores
})
#svm = SVC(probability=True, kernel='rbf', C=clf.best_params_['C'], gamma=clf.best_params_['gamma'], cache_size=2000, verbose=False)
svm = SVC(probability=True,
kernel='rbf',
C=500,
gamma=0.00005,
cache_size=2000,
verbose=False)
svm.fit(data_train, labels_train[:, 0])
print('\n Time elapsed:', timeit.default_timer() - start_time, 's')
time_total_train = timeit.default_timer() - start_time_total_train
start_time_total_test = timeit.default_timer()
print('-' * 5, 'Testing...')
result_dir = os.path.join(FLAGS.result_dir, t)
os.makedirs(result_dir, exist_ok=True)
# initialize evaluator
evaluator = putil.init_evaluator(result_dir)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_test_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
all_probabilities = None
for batch_index in range(0, len(data_items), TEST_BATCH_SIZE):
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TEST_BATCH_SIZE])
# load images for testing and pre-process
pre_process_params['training'] = False
images_test = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
images_prediction = []
images_probabilities = []
for img in images_test:
print('-' * 10, 'Testing', img.id_)
start_time = timeit.default_timer()
#probabilities, predictions = forest.predict(img.feature_matrix[0])
features = img.feature_matrix[0]
if NORMALIZE_FEATURES:
features = scipy_stats.zscore(features)
probabilities = np.array(svm.predict_proba(features))
print('probabilities: ' + str(probabilities.shape))
predictions = svm.classes_[probabilities.argmax(axis=1)]
if all_probabilities is None:
all_probabilities = np.array([probabilities])
else:
all_probabilities = np.concatenate(
(all_probabilities, [probabilities]), axis=0)
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
# convert prediction and probabilities back to SimpleITK images
image_prediction = conversion.NumpySimpleITKImageBridge.convert(
predictions.astype(np.uint8), img.image_properties)
image_probabilities = conversion.NumpySimpleITKImageBridge.convert(
probabilities, img.image_properties)
# evaluate segmentation without post-processing
evaluator.evaluate(
image_prediction,
img.images[structure.BrainImageTypes.GroundTruth], img.id_)
images_prediction.append(image_prediction)
images_probabilities.append(image_probabilities)
# post-process segmentation and evaluate with post-processing
post_process_params = {'crf_post': True}
images_post_processed = putil.post_process_batch(images_test,
images_prediction,
images_probabilities,
post_process_params,
multi_process=True)
for i, img in enumerate(images_test):
evaluator.evaluate(
images_post_processed[i],
img.images[structure.BrainImageTypes.GroundTruth],
img.id_ + '-PP')
# save results
sitk.WriteImage(
images_prediction[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG.mha'),
True)
sitk.WriteImage(
images_post_processed[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG-PP.mha'),
True)
time_total_test = timeit.default_timer() - start_time_total_test
# write summary of parameters to results dir
with open(os.path.join(result_dir, 'summary.txt'), 'w') as summary_file:
print('Result dir: {}'.format(result_dir))
print('Result dir: {}'.format(result_dir), file=summary_file)
print('SVM', file=summary_file)
print('SVM params: {}'.format(svm.get_params()), file=summary_file)
print('pre-process-params: {}'.format(pre_process_params),
file=summary_file)
print('Training data size: {}'.format(train_data_size),
file=summary_file)
print('Total training time: {:.1f}s'.format(time_total_train),
file=summary_file)
print('Total testing time: {:.1f}s'.format(time_total_test),
file=summary_file)
print('Voxel Filter Mask: {}'.format(
putil.FeatureExtractor.VOXEL_MASK_FLT),
file=summary_file)
print('Normalize Features: {}'.format(NORMALIZE_FEATURES),
file=summary_file)
#print('SVM best parameters', file=summary_file)
#print(clf.best_params_, file=summary_file)
stats = statistics.gather_statistics(
os.path.join(result_dir, 'results.csv'))
print('Result statistics:', file=summary_file)
print(stats, file=summary_file)
def main(_):
"""Brain tissue segmentation using decision forests.
The main routine executes the medical image analysis pipeline:
- Image loading
- Registration
- Pre-processing
- Feature extraction
- Decision forest classifier model building
- Segmentation using the decision forest classifier model on unseen images
- Post-processing of the segmentation
- Evaluation of the segmentation
"""
# SGD need "original" value of 0.04 for ventricles
putil.FeatureExtractor.VOXEL_MASK_FLT = [0.0003, 0.004, 0.003, 0.04]
# load atlas images
putil.load_atlas_images(FLAGS.data_atlas_dir)
print('-' * 5, 'Training...')
# generate a model directory (use datetime to ensure that the directory is empty)
# we need an empty directory because TensorFlow will continue training an existing model if it is not empty
t = datetime.datetime.now().strftime('%Y-%m-%d%H%M%S')
model_dir = os.path.join(FLAGS.model_dir, t)
os.makedirs(model_dir, exist_ok=True)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_train_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
train_data_size = len(data_items)
pre_process_params = {
'zscore_pre': True,
'coordinates_feature': True,
'intensity_feature': True,
'gradient_intensity_feature': True
}
# initialize decision forest parameters
df_params = df.DecisionForestParameters()
df_params.num_classes = 4
df_params.num_trees = 20
df_params.max_nodes = 1000
df_params.model_dir = model_dir
forest = None
clf = None
start_time_total_train = timeit.default_timer()
for batch_index in range(0, len(data_items), TRAIN_BATCH_SIZE):
cache_file_prefix = os.path.normpath(
os.path.join(
script_dir, './mia-cache/batch-' + str(batch_index) + '-' +
str(TRAIN_BATCH_SIZE)))
cache_file_train = cache_file_prefix + '-data_train.npy'
cache_file_labels = cache_file_prefix + '-data_labels.npy'
if (USE_PREPROCESS_CACHE & os.path.exists(cache_file_train)):
print('Using cache from ', cache_file_train)
data_train = np.load(cache_file_train)
labels_train = np.load(cache_file_labels)
else:
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TRAIN_BATCH_SIZE])
# load images for training and pre-process
images = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
print('pre-processing done')
# generate feature matrix and label vector
data_train = np.concatenate(
[img.feature_matrix[0] for img in images])
labels_train = np.concatenate(
[img.feature_matrix[1] for img in images])
if NORMALIZE_FEATURES:
# normalize data (mean 0, std 1)
data_train = scipy_stats.zscore(data_train)
if (USE_PREPROCESS_CACHE):
print('Writing cache')
if (not os.path.exists(os.path.dirname(cache_file_prefix))):
os.mkdir(os.path.dirname(cache_file_prefix))
data_train.dump(cache_file_train)
labels_train.dump(cache_file_labels)
if clf is None:
# cross validation to find best parameter
param = [
{
"eta0": [0.5, 0.1, 0.01, 0.001, 0.0001, 0.00001],
"alpha": [0.5, 0.1, 0.01, 0.001, 0.0001, 0.00001],
"learning_rate": ['optimal', 'constant'],
"loss": ['log', 'modified_huber']
#"max_iter": [10000, 100000]
},
]
# Best params:
#{'alpha': 0.01, 'eta0': 0.5, 'learning_rate': 'optimal', 'loss': 'modified_huber'}
n_iter = 300000 / len(data_items)
sgd = SGDClassifier(learning_rate='optimal',
eta0=0.5,
alpha=0.01,
loss='modified_huber',
penalty="l2",
max_iter=n_iter,
n_jobs=8,
shuffle=False)
clf = sgd
# Note: shuffle=True gives '"RuntimeWarning: overflow encountered in expnp.exp(prob, prob)"'
# to try several parameters with grid search
#clf = GridSearchCV(sgd, param, cv=2, n_jobs=4, verbose=3)
start_time = timeit.default_timer()
clf.fit(data_train, labels_train[:, 0])
#print('Best params: ')
#print(clf.best_params_)
print('\n training, Time elapsed:',
timeit.default_timer() - start_time, 's')
time_total_train = timeit.default_timer() - start_time_total_train
start_time_total_test = timeit.default_timer()
print('-' * 5, 'Testing...')
result_dir = os.path.join(FLAGS.result_dir, t)
os.makedirs(result_dir, exist_ok=True)
# initialize evaluator
evaluator = putil.init_evaluator(result_dir)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_test_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
all_probabilities = None
for batch_index in range(0, len(data_items), TEST_BATCH_SIZE):
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TEST_BATCH_SIZE])
# load images for testing and pre-process
pre_process_params['training'] = False
images_test = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
images_prediction = []
images_probabilities = []
for img in images_test:
print('-' * 10, 'Testing', img.id_)
start_time = timeit.default_timer()
#probabilities, predictions = forest.predict(img.feature_matrix[0])
features = img.feature_matrix[0]
if NORMALIZE_FEATURES:
features = scipy_stats.zscore(features)
probabilities = np.array(clf.predict_proba(features))
print('probabilities: ' + str(probabilities.shape))
predictions = clf.classes_[probabilities.argmax(axis=1)]
if all_probabilities is None:
all_probabilities = np.array([probabilities])
else:
all_probabilities = np.concatenate(
(all_probabilities, [probabilities]), axis=0)
print(' Time elapsed:', timeit.default_timer() - start_time, 's')
# convert prediction and probabilities back to SimpleITK images
image_prediction = conversion.NumpySimpleITKImageBridge.convert(
predictions.astype(np.uint8), img.image_properties)
image_probabilities = conversion.NumpySimpleITKImageBridge.convert(
probabilities, img.image_properties)
# evaluate segmentation without post-processing
evaluator.evaluate(
image_prediction,
img.images[structure.BrainImageTypes.GroundTruth], img.id_)
images_prediction.append(image_prediction)
images_probabilities.append(image_probabilities)
# post-process segmentation and evaluate with post-processing
post_process_params = {'crf_post': True}
images_post_processed = putil.post_process_batch(images_test,
images_prediction,
images_probabilities,
post_process_params,
multi_process=True)
for i, img in enumerate(images_test):
evaluator.evaluate(
images_post_processed[i],
img.images[structure.BrainImageTypes.GroundTruth],
img.id_ + '-PP')
# save results
sitk.WriteImage(
images_prediction[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG.mha'),
True)
sitk.WriteImage(
images_post_processed[i],
os.path.join(result_dir, images_test[i].id_ + '_SEG-PP.mha'),
True)
time_total_test = timeit.default_timer() - start_time_total_test
# write summary of parameters to results dir
with open(os.path.join(result_dir, 'summary.txt'), 'w') as summary_file:
print('Result dir: {}'.format(result_dir))
print('Result dir: {}'.format(result_dir), file=summary_file)
print('Training data size: {}'.format(train_data_size),
file=summary_file)
print('Total training time: {:.1f}s'.format(time_total_train),
file=summary_file)
print('Total testing time: {:.1f}s'.format(time_total_test),
file=summary_file)
print('Voxel Filter Mask: {}'.format(
putil.FeatureExtractor.VOXEL_MASK_FLT),
file=summary_file)
print('Normalize Features: {}'.format(NORMALIZE_FEATURES),
file=summary_file)
print('SGD', file=summary_file)
#print(clf.best_params_, file=summary_file)
stats = statistics.gather_statistics(
os.path.join(result_dir, 'results.csv'))
print('Result statistics:', file=summary_file)
print(stats, file=summary_file)
all_probabilities.astype(np.float16).dump(
os.path.join(result_dir, 'all_probabilities.npy'))
def main(_):
# generate a model directory (use datetime to ensure that the directory is empty)
# we need an empty directory because TensorFlow will continue training an existing model if it is not empty
t = datetime.datetime.now().strftime('%Y-%m-%d%H%M%S')
model_dir = os.path.join(FLAGS.model_dir, t)
os.makedirs(model_dir, exist_ok=True)
# crawl the training image directories
crawler = load.FileSystemDataCrawler(FLAGS.data_train_dir, IMAGE_KEYS,
futil.BrainImageFilePathGenerator(),
futil.DataDirectoryFilter())
data_items = list(crawler.data.items())
pre_process_params = {
'zscore_pre': True,
'coordinates_feature': True,
'intensity_feature': True,
'gradient_intensity_feature': True
}
for batch_index in range(0, len(data_items), TRAIN_BATCH_SIZE):
cache_file_prefix = os.path.normpath(
os.path.join(
script_dir, './mia-cache/batch-' + str(batch_index) + '-' +
str(TRAIN_BATCH_SIZE)))
cache_file_train = cache_file_prefix + '-data_train.npy'
cache_file_labels = cache_file_prefix + '-data_labels.npy'
if (USE_PREPROCESS_CACHE & os.path.exists(cache_file_train)):
print('Using cache from ', cache_file_train)
data_train = np.load(cache_file_train)
labels_train = np.load(cache_file_labels)
else:
# slicing manages out of range; no need to worry
batch_data = dict(data_items[batch_index:batch_index +
TRAIN_BATCH_SIZE])
# load images for training and pre-process
images = putil.pre_process_batch(batch_data,
pre_process_params,
multi_process=True)
# generate feature matrix and label vector
data_train = np.concatenate(
[img.feature_matrix[0] for img in images])
labels_train = np.concatenate(
[img.feature_matrix[1] for img in images])
# Scatter matrix plot of the train data
data = pd.DataFrame(data_train,
columns=[
'Feat. 1', 'Feat. 2', 'Feat. 3', 'Feat. 4',
'Feat. 5', 'Feat. 6', 'Feat. 7'
])
axes = pd.scatter_matrix(data, alpha=0.2, diagonal='hist')
corr = data.corr().as_matrix()
for i, j in zip(*plt.np.triu_indices_from(axes, k=1)):
axes[i, j].annotate("%.2f" % corr[i, j], (0.99, 0.98),
size=23,
xycoords='axes fraction',
ha='right',
va='top')
n = len(data.columns)
for x in range(n):
for y in range(n):
# to get the axis of subplots
ax = axes[x, y]
# to make x axis name vertical
ax.xaxis.label.set_rotation(0)
ax.xaxis.label.set_size(17)
ax.xaxis.set_label_coords(0.5, -0.3)
# to make y axis name horizontal
ax.yaxis.label.set_rotation(0)
ax.yaxis.label.set_size(17)
ax.yaxis.set_label_coords(-0.3, 0.5)
# to make sure y axis names are outside the plot area
ax.yaxis.labelpad = 50
# plt.title('Scatter Plot Matrix', fontsize=17, y=7.1, x=-2.5)
plt.show()