我是 TensorFlow 的新手。我正在尝试构建一个能够识别文档中的字母和单词的神经网络。
正如ICDAR2017中提到的那样,我将任务分为 3 个阶段:
- 文本本地化
- 裁剪的单词识别
- 端到端识别
我在文本本地化的第一阶段遇到了一些问题。我使用了一种名为EAST的架构。
架构阶段:
- 全卷积网络
- NMS合并阶段
这是我开始使用的模型。它工作正常,但我在检测某些字符和字母时遇到了一些问题,例如:
模型层:
def model(images, weight_decay=1e-5, is_training=True):
'''
define the model, we use slim's implemention of resnet
'''
images = mean_image_subtraction(images)
with slim.arg_scope(resnet_v1.resnet_arg_scope(weight_decay=weight_decay)):
logits, end_points = resnet_v1.resnet_v1_50(images, is_training=is_training, scope='resnet_v1_50')
with tf.variable_scope('feature_fusion', values=[end_points.values]):
batch_norm_params = {
'decay': 0.997,
'epsilon': 1e-5,
'scale': True,
'is_training': is_training
}
with slim.arg_scope([slim.conv2d],
activation_fn=tf.nn.relu,
normalizer_fn=slim.batch_norm,
normalizer_params=batch_norm_params,
weights_regularizer=slim.l2_regularizer(weight_decay)):
f = [end_points['pool5'], end_points['pool4'],
end_points['pool3'], end_points['pool2']]
for i in range(4):
print('Shape of f_{} {}'.format(i, f[i].shape))
g = [None, None, None, None]
h = [None, None, None, None]
num_outputs = [None, 128, 64, 32]
for i in range(4):
if i == 0:
h[i] = f[i]
else:
c1_1 = slim.conv2d(tf.concat([g[i-1], f[i]], axis=-1), num_outputs[i], 1)
h[i] = slim.conv2d(c1_1, num_outputs[i], 3)
if i <= 2:
g[i] = unpool(h[i])
else:
g[i] = slim.conv2d(h[i], num_outputs[i], 3)
print('Shape of h_{} {}, g_{} {}'.format(i, h[i].shape, i, g[i].shape))
# here we use a slightly different way for regression part,
# we first use a sigmoid to limit the regression range, and also
# this is do with the angle map
F_score = slim.conv2d(g[3], 1, 1, activation_fn=tf.nn.sigmoid, normalizer_fn=None)
# 4 channel of axis aligned bbox and 1 channel rotation angle
geo_map = slim.conv2d(g[3], 4, 1, activation_fn=tf.nn.sigmoid, normalizer_fn=None) * FLAGS.text_scale
angle_map = (slim.conv2d(g[3], 1, 1, activation_fn=tf.nn.sigmoid, normalizer_fn=None) - 0.5) * np.pi/2 # angle is between [-45, 45]
F_geometry = tf.concat([geo_map, angle_map], axis=-1)
return F_score, F_geometry
有人建议我使用Pyramid Networks,我不知道谁来将此 Pyramid Networks 与 Tensorflow 中的 EAST 模型集成,这是否值得。
我还想知道在基于表格的数据中提高文本本地化准确性的选项
