Files
PYAS/Engine/Model/train.py
T
2025-09-16 20:03:15 +08:00

133 lines
5.8 KiB
Python

import tensorflow as tf
import os, tf2onnx, numpy, random
from PIL import Image
from tensorflow.keras import *
####################################################################################################
Image.MAX_IMAGE_PIXELS = None
tf.keras.mixed_precision.set_global_policy('mixed_float16')
####################################################################################################
def get_file_list(directory):
file_paths, labels, class_indices = [], [], {}
for i, cls in enumerate(sorted([d for d in os.listdir(directory) if os.path.isdir(os.path.join(directory, d))])):
class_indices[cls] = i
cls_dir = os.path.join(directory, cls)
for root, _, files in os.walk(cls_dir):
for file in files:
if file.lower().endswith(('.jpg', '.jpeg', '.png', '.bmp', '.gif')):
file_paths.append(os.path.join(root, file))
labels.append(i)
return file_paths, labels, class_indices
####################################################################################################
def parse_fn(filename, label, image_size, channels, num_classes):
img = tf.io.read_file(filename)
img = tf.image.decode_image(img, channels=channels, expand_animations=False)
img = tf.cond(
tf.reduce_all(tf.equal(tf.shape(img)[:2], image_size)),
lambda: tf.cast(img, tf.float32),
lambda: tf.image.resize(img, image_size))
img = tf.cast(img, tf.float32) / 255.0
label = tf.one_hot(label, depth=num_classes)
return img, label
####################################################################################################
def load_dataset(data_dir, image_size=(224, 224), val_split=0.00001, batch_size=128, color_mode="grayscale"):
channels = 1 if color_mode == "grayscale" else 3
file_paths, labels, class_indices = get_file_list(data_dir)
combined = list(zip(file_paths, labels))
random.shuffle(combined)
file_paths[:], labels[:] = zip(*combined)
num_val = int(val_split * len(file_paths))
train_files = file_paths[num_val:]
train_labels = labels[num_val:]
val_files = file_paths[:num_val]
val_labels = labels[:num_val]
num_classes = len(class_indices)
train_ds = tf.data.Dataset.from_tensor_slices((train_files, train_labels))
train_ds = train_ds.map(lambda f, l: parse_fn(f, l, image_size, channels, num_classes), num_parallel_calls=tf.data.AUTOTUNE)
train_ds = train_ds.batch(batch_size).prefetch(tf.data.AUTOTUNE)
val_ds = tf.data.Dataset.from_tensor_slices((val_files, val_labels))
val_ds = val_ds.map(lambda f, l: parse_fn(f, l, image_size, channels, num_classes), num_parallel_calls=tf.data.AUTOTUNE)
val_ds = val_ds.batch(batch_size).prefetch(tf.data.AUTOTUNE)
train_ds.class_indices = class_indices
return train_ds, val_ds
####################################################################################################
def multi_conv(x, strides):
convs = []
for k in [1, 3, 5, 7]:
c = layers.DepthwiseConv2D(kernel_size=k, strides=strides, padding='same', activation='gelu')(x)
convs.append(c)
x = layers.Concatenate()(convs)
x = layers.BatchNormalization()(x)
return layers.Activation('gelu')(x)
def gated_conv(x, strides):
c = layers.DepthwiseConv2D(3, strides=strides, padding='same', activation='gelu')(x)
g = layers.DepthwiseConv2D(3, strides=strides, padding='same', activation='sigmoid')(x)
return layers.Multiply()([c, g])
def se_block(x, reduction):
filters = x.shape[-1]
s = layers.Conv2D(filters // reduction, 1, padding='same', activation='gelu')(x)
s = layers.BatchNormalization()(s)
s = layers.Conv2D(filters, 1, padding='same', activation='sigmoid')(s)
return layers.multiply([x, s])
def build_model(input_shape, num_classes):
i = layers.Input(shape=input_shape)
x = multi_conv(i, strides=1)
x = gated_conv(x, strides=2)
x = multi_conv(x, strides=2)
x = multi_conv(x, strides=2)
x = multi_conv(x, strides=2)
x = multi_conv(x, strides=2)
x = se_block(x, reduction=2)
x = layers.GlobalMaxPooling2D()(x)
o = layers.Dense(num_classes, activation='softmax', dtype='float32')(x)
return models.Model(i, o)
####################################################################################################
def lr_scheduler(epoch, lr):
return 1e-4 * (0.95 ** epoch)
class CustomModelCheckpoint(callbacks.Callback):
def on_epoch_end(self, epoch, logs=False):
models.save_model(self.model, f"PYAS_Model_Epoch_{epoch + 1}.h5")
spec = (tf.TensorSpec((None,) + train_ds.image_shape, tf.float32),)
model_proto, _ = tf2onnx.convert.from_keras(self.model, input_signature=spec, opset=18)
with open(f"PYAS_Model_Epoch_{epoch + 1}.onnx", "wb") as f:
f.write(model_proto.SerializeToString())
####################################################################################################
train_ds, val_ds = load_dataset(r'.\Image_File')
for imgs, _ in train_ds.take(1):
train_ds.image_shape = imgs.shape[1:]
break
strategy = tf.distribute.MirroredStrategy(cross_device_ops=tf.distribute.HierarchicalCopyAllReduce())
with strategy.scope():
try:
model = models.load_model('PYAS_Model_Epoch_0.h5')
print("Load model from disk")
except:
print("Creating a new model")
model = build_model(train_ds.image_shape, len(train_ds.class_indices))
print(f"Total parameters: {model.count_params()}")
model.compile(optimizer='adam', loss='categorical_crossentropy', metrics=['accuracy'])
model.fit(train_ds, epochs=30, callbacks=[CustomModelCheckpoint(), callbacks.LearningRateScheduler(lr_scheduler)], validation_data=val_ds)
input('Training Complete')