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#!/usr/bin/env python
# _*_ coding:utf-8 _*_
# ============================================
# @Time : 2020/07/01 19:00
# @Author : WanDaoYi
# @FileName : face_train.py
# ============================================
from datetime import datetime
import os
import sys
import logging
import mxnet.optimizer as optimizer
from utils.metric_utils import *
from verification_model import VerificationModel
from utils import data_utils, flops_utils, get_data_utils
from data_prepare.image_iter import FaceImageIter
from data_prepare.triplet_image_iter import TripletFaceImageIter
# 给动态方法: eval(net_name).get_symbol() 使用
from model_net import f_mobile_face_net
from config import cfg
os.environ['CUDA_VISIBLE_DEVICES'] = cfg.TRAIN.GPU_NUM
# 用于打印训练日志:
# INFO:root:Epoch[0] Batch [20-40] Speed: 19.72 samples/sec acc=0.000000 loss_value=55.078926
logger = logging.getLogger()
logger.setLevel(logging.INFO)
class FaceTrain(object):
def __init__(self):
self.verification_model = VerificationModel()
# 预训练模型文件夹路径
self.model_path = cfg.TRAIN.MODEL_PATH
self.learning_rate = cfg.TRAIN.LEARNING_RATE
# 权值衰减值
self.weight_decay = cfg.TRAIN.WEIGHT_DECAY
# 训练多少步就打印一次日志
self.print_step = cfg.TRAIN.PRINT_STEP
self.val_step = cfg.TRAIN.VAL_STEP
self.save_model_num = cfg.TRAIN.SAVE_MODEL_NUM
# 是否检测输出的特征向量
self.check_feature_flag = cfg.TRAIN.CHECK_FEATURE_FLAG
# 每达到步数,学习率变为原来的百分之十
self.learning_rate_step_list = cfg.TRAIN.LEARNING_RATE_STEP_LIST
# 人脸图像的 shape [112, 112, 3]
self.face_shape = cfg.COMMON.FACE_SHAPE
# loss 的计算方式
self.face_loss = cfg.TRAIN.FACE_LOSS
# 模型信息 字典
self.model_dict = cfg.COMMON.STRUCTURE_DICT
# net info
self.net_dict = self.model_dict["network"]
self.model_net = cfg.TRAIN.MODEL_NET
self.net_info = self.net_dict[self.model_net]
print("net_info: {}".format(self.net_info))
# data info
self.data_dict = self.model_dict["data_set"]
self.data_set = cfg.TRAIN.DATA_SET
self.data_info = self.data_dict[self.data_set]
print("data_info: {}".format(self.data_info))
# loss info
self.loss_dict = self.model_dict["loss"]
self.loss_info = self.loss_dict[cfg.TRAIN.FACE_LOSS]
print("loss_info: {}".format(self.loss_info))
# 模型保存文件夹路径
self.save_model_file_path = cfg.TRAIN.SAVE_MODEL_FILE_PATH
# 保存模型名的前缀
self.save_model_prefix = "{}_{}_{}".format(self.model_net, self.face_loss, self.data_set)
self.save_model_path = os.path.join(self.save_model_file_path, self.save_model_prefix)
data_utils.make_file(self.save_model_path)
self.save_model_prefix_path = self.save_model_path + cfg.TRAIN.MODEL_NAME_PREFIX
self.max_steps = cfg.TRAIN.MAX_STEPS
self.kv_store = cfg.TRAIN.KV_STORE
# 学习率的倍数
self.fc7_lr_multiple = cfg.TRAIN.FC7_LR_MULTIPLE
# 权重刷衰减的倍数
self.fc7_wd_multiple = cfg.TRAIN.FC7_WD_MULTIPLE
# fc7 是否有 bias 层
self.fc7_no_bias = cfg.TRAIN.FC7_NO_BIAS
# Focal loss,一种改进的交叉损失熵
self.ce_loss = cfg.TRAIN.CE_LOSS
# 是否计算一个网络占用的浮点数内存
self.count_flops_flag = cfg.TRAIN.COUNT_FLOPS_FLAG
# 输出特征维度: 128
self.embedding_size = cfg.COMMON.EMBEDDING_SIZE
# .idx 后缀
self.idx_suffix = cfg.COMMON.IDX_SUFFIX
self.data_rand_mirror_flag = cfg.TRAIN.DATA_RAND_MIRROR_FLAG
self.data_crop_flag = cfg.TRAIN.DATA_CROP_FLAG
self.data_color_aug = cfg.TRAIN.DATA_COLOR_AUG
self.data_image_filter = cfg.TRAIN.DATA_IMAGES_FILTER
pass
def get_symbol(self):
net_name = self.net_info["net_name"]
# 输出特征向量的维度, 默认输出 128 维
emb_size = self.net_info["emb_size"] if "emb_size" in self.net_info else self.embedding_size
# 每个 GPU 的 batch size
per_batch_size = self.net_info["per_batch_size"]
loss_name = self.loss_info["loss_name"]
class_num = self.data_info["class_num"]
print("class_num: {}".format(class_num))
# 获得一个特征向量
# 动态方法: eval(net_name) 为将字符串名转为方法名,
# 例如: 字符串: "f_mobile_face_net" ---> 方法: f_mobile_face_net
# eval("f_mobile_face_net").get_symbol() ---> f_mobile_face_net.get_symbol()
embedding_feature = eval(net_name).get_symbol()
# print("embedding_feature: {}".format(embedding_feature))
out_list = [mx.symbol.BlockGrad(embedding_feature)]
# 定义一个标签的占位符,用来存放标签
gt_label = mx.symbol.Variable('softmax_label')
if loss_name == "softmax":
# 定义一个全连接层的权重,使用全局池化代替全链接层
fc_weight_init = mx.symbol.Variable("fc7_weight",
shape=(class_num, emb_size),
lr_mult=self.fc7_lr_multiple,
wd_mult=self.fc7_wd_multiple,
init=mx.init.Normal(0.01))
# 如果不设置bias,使用全局池化代替全链接层,得到每个id的概率值
if self.fc7_no_bias:
fc7 = mx.sym.FullyConnected(data=embedding_feature,
weight=fc_weight_init,
no_bias=True,
num_hidden=class_num,
name='fc7')
pass
# 如果设置_bias,使用全局池化代替全链接层,得到每个id的cos_t
else:
fc_bias = mx.symbol.Variable('fc7_bias', lr_mult=2.0, wd_mult=0.0)
fc7 = mx.sym.FullyConnected(data=embedding_feature,
weight=fc_weight_init,
bias=fc_bias,
num_hidden=class_num,
name='fc7')
pass
softmax = mx.symbol.SoftmaxOutput(data=fc7,
label=gt_label,
name='softmax',
normalization='valid')
out_list.append(softmax)
if self.ce_loss:
# ce_loss = mx.symbol.softmax_cross_entropy(data=fc7,
# label=gt_label,
# name='ce_loss')/per_batch_size
body = mx.symbol.SoftmaxActivation(data=fc7)
body = mx.symbol.log(body)
one_hot_label = mx.sym.one_hot(gt_label, depth=class_num, on_value=-1.0, off_value=0.0)
body = body * one_hot_label
ce_loss = mx.symbol.sum(body) / per_batch_size
out_list.append(mx.symbol.BlockGrad(ce_loss))
pass
pass
elif loss_name == "margin_softmax":
# 定义一个全连接层的权重,使用全局池化代替全链接层
fc_weight_init = mx.symbol.Variable("fc7_weight",
shape=(class_num, emb_size),
lr_mult=self.fc7_lr_multiple,
wd_mult=self.fc7_wd_multiple,
init=mx.init.Normal(0.01))
# 获得loss中m的缩放系数, L4 loss 公式中的:
# e^{s[cos(m_1 * theta_y_i + m_2) - m_3]}
s = self.loss_info["loss_s"]
m_1 = self.loss_info["loss_m1"]
m_2 = self.loss_info["loss_m2"]
m_3 = self.loss_info["loss_m3"]
# 先进行L2正则化,然后进行全链接
l2_norm_fc_weight_init = mx.symbol.L2Normalization(fc_weight_init, mode='instance')
l2_norm_embedding = mx.symbol.L2Normalization(embedding_feature, mode='instance', name='fc1n') * s
# with ag.pause(train_mode=True):
# 使用全局池化代替全链接层,得到每个id的角度*64
fc7 = mx.sym.FullyConnected(data=l2_norm_embedding, weight=l2_norm_fc_weight_init,
no_bias=True, num_hidden=class_num, name='fc7')
# 查看 fc7_out_shape
in_shape, out_shape, uax_shape = fc7.infer_shape(data=(2, 3, 112, 112))
print("fc7_out_shape: {}".format(out_shape))
# 其存在m1,m2,m3是为了把算法整合在一起,
# arcface cosface combined
if m_1 != 1.0 or m_2 != 0.0 or m_3 != 0.0:
# cosface loss
if m_1 == 1.0 and m_2 == 0.0:
s_m = s * m_3
gt_one_hot = mx.sym.one_hot(gt_label, depth=class_num, on_value=s_m, off_value=0.0)
fc7 = fc7 - gt_one_hot
pass
# arcface combined
else:
# fc7每一行找出 gt_label 对应的值,即 角度 * s
zy = mx.sym.pick(fc7, gt_label, axis=1)
# in_shape, out_shape, uax_shape = zy.infer_shape(data=(2, 3, 112, 112), softmax_label=(2,))
# # print('zy', out_shape)
# 进行复原,前面乘以了 s,cos_t 为 -1 到 1 之间
cos_t = zy / s
# t为0-3.14之间
# 该 arccos 是为了让后续的cos单调递增
t = mx.sym.arccos(cos_t)
# m1 sphereface
if m_1 != 1.0:
t = t * m_1
# arcface 或者 combined
if m_2 > 0.0:
t = t + m_2
# t为 0-3.14 之间,单调递增
body = mx.sym.cos(t)
# combined 或者 arcface
if m_3 > 0.0:
body = body - m_3
new_zy = body * s
# 得到差值
diff = new_zy - zy
# 扩展一个维度
diff = mx.sym.expand_dims(diff, 1)
# 把标签转化为 one_hot 编码
gt_one_hot = mx.sym.one_hot(gt_label, depth=class_num, on_value=1.0, off_value=0.0)
# 进行更新
body = mx.sym.broadcast_mul(gt_one_hot, diff)
fc7 = fc7 + body
pass
pass
softmax = mx.symbol.SoftmaxOutput(data=fc7,
label=gt_label,
name='softmax',
normalization='valid')
out_list.append(softmax)
if self.ce_loss:
# ce_loss = mx.symbol.softmax_cross_entropy(data=fc7,
# label=gt_label,
# name='ce_loss')/per_batch_size
body = mx.symbol.SoftmaxActivation(data=fc7)
body = mx.symbol.log(body)
one_hot_label = mx.sym.one_hot(gt_label, depth=class_num, on_value=-1.0, off_value=0.0)
body = body * one_hot_label
ce_loss = mx.symbol.sum(body) / per_batch_size
out_list.append(mx.symbol.BlockGrad(ce_loss))
pass
pass
elif loss_name.find("triplet") >= 0:
triplet_alpha = self.loss_info["triplet_alpha"]
l2_norm_embedding = mx.symbol.L2Normalization(embedding_feature, mode='instance', name='fc1n')
anchor = mx.symbol.slice_axis(l2_norm_embedding, axis=0,
begin=0,
end=per_batch_size // 3)
# 正样本
positive = mx.symbol.slice_axis(l2_norm_embedding, axis=0,
begin=per_batch_size // 3,
end=2 * per_batch_size // 3)
# 负样本
negative = mx.symbol.slice_axis(l2_norm_embedding, axis=0,
begin=2 * per_batch_size // 3,
end=per_batch_size)
if loss_name == "triplet":
ap = anchor - positive
an = anchor - negative
ap = ap * ap
an = an * an
# (T,1)
ap = mx.symbol.sum(ap, axis=1, keepdims=1)
# (T,1)
an = mx.symbol.sum(an, axis=1, keepdims=1)
triplet_loss = mx.symbol.Activation(data=(ap - an + triplet_alpha), act_type='relu')
triplet_loss = mx.symbol.mean(triplet_loss)
pass
else:
ap = anchor * positive
an = anchor * negative
# (T,1)
ap = mx.symbol.sum(ap, axis=1, keepdims=1)
# (T,1)
an = mx.symbol.sum(an, axis=1, keepdims=1)
ap = mx.sym.arccos(ap)
an = mx.sym.arccos(an)
triplet_loss = mx.symbol.Activation(data=(ap - an + triplet_alpha), act_type='relu')
triplet_loss = mx.symbol.mean(triplet_loss)
pass
triplet_loss = mx.symbol.MakeLoss(triplet_loss)
out_list.append(mx.sym.BlockGrad(gt_label))
out_list.append(triplet_loss)
pass
# 聚集所有的符号
out = mx.symbol.Group(out_list)
print("out: {}".format(out))
return out
pass
def do_train(self):
# 判断使用GPU还是CPU
ctx = []
cvd = os.environ['CUDA_VISIBLE_DEVICES'].strip()
if len(cvd) > 0:
gpu_num_list = cvd.split(",")
gpu_num_list_len = len(gpu_num_list)
for i in range(gpu_num_list_len):
ctx.append(mx.gpu(i))
pass
pass
if len(ctx) == 0:
ctx = [mx.cpu()]
print("use cpu")
pass
else:
print("gpu num: {}".format(ctx))
pass
assert self.face_shape[0] == self.face_shape[1], "face_shape[0] neq face_shape[1]"
# 每个 GPU 的 batch size
per_batch_size = self.net_info["per_batch_size"]
ctx_count = len(ctx)
batch_size = per_batch_size * ctx_count
data_shape = [self.face_shape[2], self.face_shape[0], self.face_shape[1]]
data_shape = tuple(data_shape)
# 模型是否存在,如果存在则加载模型,如果不存在则初始化权重
if os.path.exists(self.model_path):
path_info, file_name = os.path.split(self.model_path)
name_info, suffix_info = os.path.splitext(file_name)
name_prefix, name_epoch = name_info.split("-")
model_path_prefix = os.path.join(path_info, name_prefix)
epoch_num = int(name_epoch)
symbol, arg_params, aux_params = mx.model.load_checkpoint(model_path_prefix, epoch_num)
# 模型构建
symbol_info = self.get_symbol()
pass
else:
arg_params = None
aux_params = None
# 模型构建
symbol_info = self.get_symbol()
pass
# 计算模型的缓存空间
if self.count_flops_flag:
all_layers = symbol_info.get_internals()
fc1_sym = all_layers['fc1_output']
flops_info = flops_utils.count_flops(fc1_sym, data=(1, data_shape[0], data_shape[1], data_shape[2]))
flops_info_str = flops_utils.flops_str(flops_info)
print("Network flops_info_str: {}".format(flops_info_str))
pass
model = mx.mod.Module(context=mx.gpu(),
# context=ctx,
symbol=symbol_info)
loss_name = self.loss_info["loss_name"]
rec_data_path = self.data_info["rec_data_path"]
idx_data_path = self.data_info["idx_data_path"]
bin_data_file_path = self.data_info["bin_data_file_path"]
val_targets_list = self.data_info["val_targets"]
# 加载 .bin data 验证数据
bin_data_list = get_data_utils.load_bin(bin_data_file_path=bin_data_file_path,
bin_name_list=val_targets_list,
image_shape=self.face_shape)
# 主要获取数据的迭代器,triplet 与 sfotmax 输入数据的迭代器是不一样的,
# 具体哪里不一样,后续章节为大家分析
if loss_name.find("triplet") >= 0:
triplet_bag_size = self.loss_info["triplet_bag_size"]
triplet_alpha = self.loss_info["triplet_alpha"]
triplet_max_ap = self.loss_info["triplet_max_ap"]
images_per_identity = self.loss_info["images_per_identity"]
triplet_params = [triplet_bag_size, triplet_alpha, triplet_max_ap]
train_data_iter = TripletFaceImageIter(rec_data_path=rec_data_path,
idx_data_path=idx_data_path,
batch_size=batch_size,
data_shape=data_shape,
shuffle_flag=True,
rand_mirror=self.data_rand_mirror_flag,
cutoff=self.data_crop_flag,
ctx_num=ctx_count,
images_per_identity=images_per_identity,
triplet_params=triplet_params,
mx_model=model
)
metric2 = LossValueMetric()
eval_metrics = [mx.metric.create(metric2)]
pass
else:
train_data_iter = FaceImageIter(rec_data_path=rec_data_path,
idx_data_path=idx_data_path,
batch_size=batch_size,
data_shape=data_shape,
shuffle_flag=True,
rand_mirror=self.data_rand_mirror_flag,
cutoff=self.data_crop_flag,
color_jitter=self.data_color_aug,
images_filter=self.data_image_filter
)
metric1 = AccMetric()
eval_metrics = [mx.metric.create(metric1)]
# Focal loss,一种改进的交叉损失熵
if self.ce_loss:
metric2 = LossValueMetric()
eval_metrics.append(mx.metric.create(metric2))
pass
pass
# 把 train_data_iter 转化为 mx.io.PrefetchingIter 迭代器
train_data_iter = mx.io.PrefetchingIter(train_data_iter)
net_name = self.net_info["net_name"]
if net_name == "f_res_net" or net_name == "f_mobile_face_net":
# resNet style
initializer = mx.init.Xavier(rnd_type='gaussian', factor_type="out", magnitude=2)
pass
else:
initializer = mx.init.Xavier(rnd_type='uniform', factor_type="in", magnitude=2)
pass
re_scale = 1.0 / ctx_count
optimize = optimizer.Adam(learning_rate=self.learning_rate, wd=self.weight_decay, rescale_grad=re_scale)
callback_speed = mx.callback.Speedometer(batch_size, self.print_step)
# 最高的准曲率 lfw and target
highest_acc = [0.0, 0.0]
global_step = [0]
save_step = [0]
print("learning_rate_step_list: {}".format(self.learning_rate_step_list))
def batch_callback_fun(param):
global_step[0] += 1
m_batch = global_step[0]
for step in self.learning_rate_step_list:
if m_batch == step:
optimize.lr *= 0.1
print("learning rate change to: {}".format(optimize.lr))
break
pass
pass
# print(param)
callback_speed(param)
# 每1000批次进行一次打印
if m_batch % 1000 == 0:
print("learning_rate: {}\nbatch: {}\n epoch: {}".format(optimize.lr, param.nbatch, param.epoch))
pass
if m_batch >= 0 and m_batch % self.val_step == 0:
acc_list = self.ver_test(bin_data_list=bin_data_list,
val_targets_list=val_targets_list,
model_net=model,
batch_size=batch_size,
n_batch=m_batch)
save_step[0] += 1
m_save = save_step[0]
do_save_flag = False
is_highest_flag = False
print("-" * 100)
# 如果存在评估集
print("acc_list: {}".format(acc_list))
if len(acc_list) > 0:
score = sum(acc_list)
if acc_list[-1] >= highest_acc[-1]:
if acc_list[-1] > highest_acc[-1]:
is_highest_flag = True
pass
else:
if score >= highest_acc[0]:
is_highest_flag = True
highest_acc[0] = score
pass
pass
highest_acc[-1] = acc_list[-1]
pass
pass
# 判断是否保存模型
if is_highest_flag:
do_save_flag = True
pass
if self.save_model_num == 0:
do_save_flag = False
pass
elif self.save_model_num == 2:
do_save_flag = True
pass
elif self.save_model_num == 3:
m_save = 1
pass
if do_save_flag:
print("m_save: {}".format(m_save))
arg, aux = model.get_params()
if self.check_feature_flag:
all_layers = model.symbol.get_internals()
fc1_sym = all_layers["fc1_output"]
arg_base = {}
for key in arg:
if not key.startswith("fc7"):
arg_base[key] = arg[key]
pass
pass
mx.model.save_checkpoint(self.save_model_prefix_path, m_save, fc1_sym, arg_base, aux)
pass
else:
mx.model.save_checkpoint(self.save_model_prefix_path, m_save, model.symbol, arg, aux)
pass
pass
print("highest_acc[m_batch: {}]: {:.5f}".format(m_batch, highest_acc[-1]))
pass
# 如果最大步骤大于 0, 且 训练步骤 > 最大步骤, 则退出程序
if self.max_steps > 0 and m_batch > self.max_steps:
sys.exit(0)
pass
pass
begin_epoch = 0
# 训练模型
model.fit(train_data=train_data_iter,
begin_epoch=begin_epoch,
num_epoch=999999,
eval_metric=eval_metrics,
kvstore=self.kv_store,
optimizer=optimize,
initializer=initializer,
arg_params=arg_params,
aux_params=aux_params,
allow_missing=True,
batch_end_callback=batch_callback_fun
)
pass
def ver_test(self, bin_data_list, val_targets_list, model_net, batch_size, n_batch, k_folds=8):
acc_result_list = []
bin_data_list_len = len(bin_data_list)
for bin_data_index in range(bin_data_list_len):
acc, std, feature_norm, feature_list = self.verification_model.test_details(bin_data_list[bin_data_index],
model_net=model_net,
batch_size=batch_size,
k_folds=k_folds)
bin_name_info = os.path.splitext(val_targets_list[bin_data_index])[0]
print("[{}][{}] XNorm: {:.5f}".format(bin_name_info, n_batch, feature_norm))
print("[{}]acc: {:.5f}+-{:.5f}".format(bin_name_info, acc, std))
acc_result_list.append(acc)
pass
return acc_result_list
pass
if __name__ == "__main__":
# 代码开始时间
start_time = datetime.now()
print("开始时间: {}".format(start_time))
demo = FaceTrain()
demo.do_train()
# 代码结束时间
end_time = datetime.now()
print("结束时间: {}, 训练模型耗时: {}".format(end_time, end_time - start_time))