现在有这样的一个场景:给一张行人的小矩形框图片, 根据该行人的特征识别出性别。

 

分析:

(1),行人的姿态各异,变化多端。很难提取图像的特定特征

(2),正常人肉眼判别行人的根据是身材比例,头发长度等。(如果是冬天的情况下,行人穿着厚实,性别识别更加难)

 

solution:

针对难以提取特定特征的图像,可以采用卷积神经网络CNN去自动提取并训练。

 

数据准备: 

采用 PETA数据集,Pedestrain Attribute Recognition At Far Distance。 该数据集一共包含了19000张标记了行人穿着及性别信息的图片。 

Peta dataset source url:   http://mmlab.ie.cuhk.edu.hk/projects/PETA.html

使用caffe训练自己的CNN

 

数据处理:

针对下载解压之后的数据集,采用的流程是:

(1)对每一张图片进行resize, resize到特定的大小(实验中定为50*150), 

(2)对正类负类样本的不均衡情况,进行rebalance处理,实验中对少数类样本进行随机选择n张进行data augmentation之后重新加入到dataset中。 

(3)划分training set和testing set, 根据train/test ratio将整个数据样本随机分为两部分。

(4)对training set 进行data augmentation 处理。 扩大训练数据量。 (操作包括: 翻转,滤波等)

#!/usr/bin/env python 
#-*- encoding: utf-8 -*- 

#########
## The python code to preprocess the images and resize them into (50, 150)
## Date: 2016-09-19
#########

import os, sys, cv2 
import numpy as np 
import random 


image_cnt = 0 
MIN_HEIGHT = 120 
MIN_WIDTH = 40 
targetLabel = [] 

positive_cnt = 0 
negative_cnt = 0 

def readImage( filePath , targetDir ):
	global image_cnt, positive_cnt, negative_cnt 
	global targetLabel 
	if not os.path.isdir( filePath ):
		print('{} is not a dir'.format(filePath)) 
		return None 
	listFile = os.listdir( filePath ) 
	labelDict = {} 
	with open( filePath + 'Label.txt', 'r') as reader:
		for line in reader:
			lines = line.split() 
			for i in range(1, len(lines)):
				if lines[i] == 'personalMale':
					label = 1 
				elif lines[i] == 'personalFemale':
					label = 0 
				else:
					continue 
				labelDict[lines[0]] = label 
				break 

	for i in range(len(listFile)):
		if len(listFile[i]) > 4 and (listFile[i][-4:] == '.bmp' or listFile[i][-4:] == '.jpg' or 
			listFile[i][-4:] == '.png' or listFile[i][-5:] == '.jpeg'):
			imageName = filePath + listFile[i] 
			img = cv2.imread( imageName ) 
			if not img.data:
				continue 
			height, width = img.shape[:2] 
			if height < MIN_HEIGHT or width < MIN_WIDTH:
				continue 
			fileName = str( image_cnt ) + '.jpeg' 
			identity = listFile[i].find('_')  
			if  identity == -1:
				identity = len(listFile[i])  
			idd = listFile[i][:identity] 
			if labelDict.has_key( idd ) :
				targetLabel.append([ fileName, labelDict[idd]]) 
				if labelDict[idd] == 0:
					negative_cnt += 1 
				else:
					positive_cnt += 1 
				img = cv2.resize(img, (50, 150), interpolation=cv2.INTER_CUBIC) 
				cv2.imwrite(targetDir + fileName, img) 
				image_cnt += 1 
			else:
				print('file {} do not have label'.format(listFile[i]) )


####### pyramid operator 
def MinAndEnlarge(img, Minus_pixel = 3):
	img = img[(3*Minus_pixel):(150 - 3*Minus_pixel), Minus_pixel:(50 - Minus_pixel), :] 
	img = cv2.resize(img, (50, 150), interpolation = cv2.INTER_CUBIC ) 
	return img 

####### rotate operator 
def Flip(img, operator = 1):
	if operator == 1:
		img = cv2.flip(img, 1) 
	else:
		img = cv2.flip(img, 0) 
	return img 

####### median blurring the image 
def Blur(img, kernel_size=5):
	img = cv2.medianBlur(img, kernel_size) 
	return img 


def EnlargeData( filePath , targetDir ):
	global image_cnt, targetLabel  
	total_sample = len(targetLabel) 
	for i in range(total_sample): 
		img = cv2.imread( filePath + targetLabel[i][0] ) 
		fileLabel = targetLabel[i][1] 
		if not img.data:
			print('no exits image file {}'.format( filePath + targetLabel[i][0]) ) 
		# 
		img1 = MinAndEnlarge(img, 3) 
		fileName = str(image_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img1 ) 
		image_cnt += 1 
		targetLabel.append( [fileName, fileLabel] ) 
		# 
		img2 = Flip(img1) 
		fileName = str(image_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img2 ) 
		image_cnt += 1 
		targetLabel.append( [fileName, fileLabel] ) 
		# 
		img3 = Blur(img, 5) 
		fileName = str(image_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img3 ) 
		image_cnt += 1 
		targetLabel.append( [fileName, fileLabel] ) 
		# 
		img4 = Blur(img1, 5) 
		fileName = str(image_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img4 ) 
		image_cnt += 1 
		targetLabel.append([fileName, fileLabel]) 
		# 
		img5 = Blur(img2, 5) 
		fileName = str(image_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img5 ) 
		image_cnt += 1 
		targetLabel.append([fileName, fileLabel]) 
	print('The total number of images is {}'.format(image_cnt)) 



def saveLabel( targetDir ): 
	global targetLabel 
	with open(targetDir + 'label.txt', 'w') as writer:
		for i in range(len(targetLabel)):
			writer.write( str( targetLabel[i][0] ) + ' ' + str(targetLabel[i][1]) + 'n' ) 


##### ReBalance operator 
#######  num (the number of minority class should added)
#######  n_or_p (the label of minority class) 
#######  op_chose( 1--symmetrical flip; 0--rotate image; )
def ReBalance( targetDir, num, n_or_p, op_chose = 0): 
	global targetLabel, image_cnt  
	total_sample = len(targetLabel)
	Contain = {} 
	while 1:
		if num <= 0:
			break 
		key_id = random.randint(0, total_sample-1) 
		if Contain.has_key( key_id ) or targetLabel[key_id][1] != n_or_p:
			continue 
		img = cv2.imread( targetDir + targetLabel[key_id][0] ) 
		if op_chose == 0:
			img = cv2.flip(img, 1)  
		elif op_chose == 1:
			img = cv2.flip(img, 0)
		fileName = str(image_cnt) + '.jpeg'  
		cv2.imwrite(targetDir + fileName, img) 
		image_cnt += 1  
		targetLabel.append([fileName, n_or_p]) 
		num -= 1 
	print('Finish add {} images'.format(image_cnt - total_sample))  
	print('Now the class is balanced and total num is {}'.format(image_cnt))  
	print('image_cnt is {} and len(_targetLabel_) is {} '.format(image_cnt, len(targetLabel))) 


def divide( targetDir, trainDir, testDir, test_ratio = 0.20):
	global targetLabel 
	total_sample = len(targetLabel) 
	assert( test_ratio < 1) 
	test_num = int(total_sample * test_ratio ) 
	test_half_num = test_num // 2; ml_cnt = 0; fm_cnt = 0 
	testLabel = [] ; trainLabel = [] 
	for i in range(total_sample):
		if  ml_cnt < test_half_num and targetLabel[i][1] == 1:
			ml_cnt += 1 
			img = cv2.imread( targetDir + targetLabel[i][0] ) 
			cv2.imwrite( testDir +  targetLabel[i][0], img ) 
			testLabel.append(targetLabel[i]) 
		elif fm_cnt < test_half_num and targetLabel[i][1] == 0:
			fm_cnt += 1 
			img = cv2.imread( targetDir + targetLabel[i][0] ) 
			cv2.imwrite( testDir +  targetLabel[i][0], img ) 
			testLabel.append(targetLabel[i]) 
		else:
			img = cv2.imread( targetDir + targetLabel[i][0] ) 
			cv2.imwrite( trainDir + targetLabel[i][0], img ) 
			trainLabel.append(targetLabel[i])  
	# train
	with open( trainDir + 'label.txt', 'w') as writer:
		for i in range(len(trainLabel)):
			writer.write( str( trainLabel[i][0] ) + ' ' + str(trainLabel[i][1]) + 'n' ) 	
	with open( testDir + 'label.txt', 'w') as writer:
		for i in range(len(testLabel)):
			writer.write( str(testLabel[i][0]) + ' ' + str(testLabel[i][1]) + 'n') 
	print('has divide into train with {} samples and test with {} samples'.format(len(trainLabel), len(testLabel)) )  
	return trainLabel, testLabel 

def DivideSet( targetDir, trainDir, testDir, test_ratio = 0.20):
	global targetLabel 
	total_sample = len(targetLabel) 
	assert( test_ratio < 1 ) 
	test_num = int(test_ratio * total_sample) 
	test_half_num = test_num //2 ; ml_cnt = test_half_num; fm_cnt = test_half_num  
	testLabel = [] ; trainLabel = [] ; testDict = {} 
	while ml_cnt > 0 or fm_cnt > 0:
		idd = random.randint(0, total_sample-1) 
		if testDict.has_key( targetLabel[idd][0] ):
			continue 
		if targetLabel[idd][1] == 1 and ml_cnt > 0:
			img = cv2.imread( targetDir + targetLabel[idd][0] ) 
			cv2.imwrite( testDir + targetLabel[idd][0], img ) 
			testLabel.append( targetLabel[idd] ) 
			testDict[targetLabel[idd][0]] = idd 
			ml_cnt -= 1 
		if targetLabel[idd][1] == 0 and fm_cnt > 0:
			img = cv2.imread( targetDir + targetLabel[idd][0] ) 
			cv2.imwrite( testDir + targetLabel[idd][0], img ) 
			testLabel.append( targetLabel[idd] ) 
			testDict[targetLabel[idd][0]] = idd 
			fm_cnt -= 1 
	for i in range(total_sample):
		if not testDict.has_key( targetLabel[i][0] ):
			trainLabel.append( targetLabel[i] ) 
			img = cv2.imread( targetDir + targetLabel[i][0] ) 
			cv2.imwrite( trainDir + targetLabel[i][0], img ) 
	## save the trainset and testset 
	with open( trainDir + 'label.txt', 'w') as writer:
		for i in range(len(trainLabel)):
			writer.write( str( trainLabel[i][0] ) + ' ' + str(trainLabel[i][1]) + 'n' ) 	
	with open( testDir + 'label.txt', 'w') as writer:
		for i in range(len(testLabel)):
			writer.write( str(testLabel[i][0]) + ' ' + str(testLabel[i][1]) + 'n') 
	print('has divide into train with {} samples and test with {} samples'.format(len(trainLabel), len(testLabel)) )  
	return trainLabel, testLabel 



def EnlargeTrain( fileDir, targetDir, trainLabel , start_cnt):
	total_sample = len(trainLabel) 
	new_cnt = start_cnt     
	for i in range(total_sample):
		img = cv2.imread( fileDir + trainLabel[i][0] ) 
		fileLabel = trainLabel[i][1] 
		if not img.data:
			print('no exits image file {}'.format( fileDir + trainLabel[i][0]) ) 
			continue 
		# 
		img1 = MinAndEnlarge(img, 3) 
		fileName = str(new_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img1 ) 
		new_cnt += 1 
		trainLabel.append( [fileName, fileLabel] ) 
		# 
		img2 = Flip(img1) 
		fileName = str(new_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img2 ) 
		new_cnt += 1 
		trainLabel.append( [fileName, fileLabel] ) 
		# 
		img3 = Blur(img, 5) 
		fileName = str(new_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img3 ) 
		new_cnt += 1 
		trainLabel.append( [fileName, fileLabel] ) 
		# 
		img4 = Blur(img1, 5) 
		fileName = str(new_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img4 ) 
		new_cnt += 1 
		trainLabel.append([fileName, fileLabel]) 
		# 
		img5 = Blur(img2, 5) 
		fileName = str(new_cnt) + '.jpeg' 
		cv2.imwrite( targetDir + fileName, img5 ) 
		new_cnt += 1 
		trainLabel.append([fileName, fileLabel]) 
	print('The total number of training images is {}'.format(new_cnt)) 
	with open( targetDir + 'label.txt', 'w') as writer:
		for i in range(len(trainLabel)):
			writer.write( str( trainLabel[i][0] ) + ' ' + str(trainLabel[i][1]) + 'n' ) 
	print('The trainLabel size is {}'.format(len(trainLabel)) ) 

if __name__ == '__main__':
	fileHead = '/home/zhangyd/source/PETA_dataset/' 
	filePath = ['3DPeS', 'CAVIAR4REID', 'CUHK', 'GRID','MIT', 'PRID','SARC3D','TownCentre', 'VIPeR','i-LID']  
	savePath = '/home/zhangyd/source/peta/' 
	for i in range(len(filePath)):
		path = fileHead + filePath[i] + '/archive/' 
		print ('runing dataset {}'.format(filePath[i]) )  
		readImage( path, savePath ) 
		print ('The cnt is {}'.format( image_cnt )) 
	#EnlargeData( savePath, savePath ) 
	saveLabel( savePath ) 
	print( 'we have {} positive labels and {} negative labels '.format( positive_cnt, negative_cnt ))
	if positive_cnt > negative_cnt:
		add_num = positive_cnt - negative_cnt 
		ReBalance( savePath, add_num, 0, 0) 
	else:
		add_num = negative_cnt - positive_cnt 
		ReBalance( savePath, add_num, 1, 0) 
	print('The total dataset is in {}'.format(savePath)) 
	TrainsavePath = '/home/zhangyd/source/peta_v1/petaTrain/' 
	TestsavePath = '/home/zhangyd/source/peta_v1/petaTest/'
	trainLabel, testLabel =  DivideSet(savePath, TrainsavePath, TestsavePath, 0.2 ) 
	start_cnt = len(targetLabel) 
	EnlargeTrain( TrainsavePath, TrainsavePath, trainLabel, start_cnt ) 
	print('the end')
	

  

实验

使用caffe的create_lmdb.sh 转换图像数据 成 imbd数据集。

定义 prototxt 等信息。 

CNN 的结构是: 

使用caffe训练自己的CNN

训练的参数设置:

# The train/test net protocol buffer definition
net: "examples/peta/petanet_train_test.prototxt"
# test_iter specifies how many forward passes the test should carry out.
# In the case of MNIST, we have test batch size 100 and 100 test iterations,
# covering the full 10,000 testing images.
test_iter: 100
# Carry out testing every 500 training iterations.
test_interval: 500
# The base learning rate, momentum and the weight decay of the network.
base_lr: 0.01
momentum: 0.9
weight_decay: 0.0005
# The learning rate policy
lr_policy: "inv"
gamma: 0.0001
power: 0.75
# Display every 100 iterations
display: 100
# The maximum number of iterations
max_iter: 10000
# snapshot intermediate results
snapshot: 5000
snapshot_prefix: "examples/peta/petanet"
# solver mode: CPU or GPU
solver_mode: GPU

 

使用论文《Learned vs. Hand-Crafted Features for Pedestrian Gender Recognition》中的网络结构,取得了较好的训练结果:

I0922 00:07:32.204310 16398 solver.cpp:337] Iteration 10000, Testing net (#0)
I0922 00:07:34.001411 16398 solver.cpp:404]     Test net output #0: accuracy = 0.8616
I0922 00:07:34.001471 16398 solver.cpp:404]     Test net output #1: loss = 0.721973 (* 1 = 0.721973 loss)
I0922 00:07:34.001479 16398 solver.cpp:322] Optimization Done.
I0922 00:07:34.001485 16398 caffe.cpp:254] Optimization Done.

 

实验分析:

因为网络不大,网络也比较简单,在GPU下进行训练,消耗的显存大概是几百M,不到1G的显存。网络结构经典,也取得较好的训练结果。

 

 

我的拓展: 自己设计的CNN网络

吸取了GoogleNet的网络特征, 引入inception, 重新设计网络。 

是两个 inception 组成, 后面加上一个FC层。 

其中Snapshot的网络结构prototxt文件是:

name: "petaNet" 
layer {
	name: "data" 
	type: "Input" 
	top: "data" 
	input_param {
		shape: {
			dim: 1 
			dim: 3 
			dim: 50 
			dim: 150 
		}
	}
}


### ------------

layer {
	name: "conv1" 
	type: "Convolution" 
	bottom: "data" 
	top: "conv1" 
	param {
		lr_mult: 1 
	}
	param {
		lr_mult: 2 
	}
	convolution_param {
		num_output: 20 
		kernel_size: 3 
		stride: 1 
		weight_filler {
			type: "xavier" 
		}
		bias_filler {
			type: "constant" 
		}
	}
}
layer {
	name: "relu1" 
	type: "ReLU" 
	bottom: "conv1" 
	top: "conv1" 
}

##-------
# Inception 3a
##-------

layer {
	name: "inc1_conv1" 
	bottom: "conv1" 
	top: "inc1_conv1" 
	type: "Convolution" 
	param {	lr_mult: 1 } 
	param {	lr_mult: 2 } 
	convolution_param {
		num_output: 20 
		kernel_size: 7 
		stride: 1 
		weight_filler {	type: "xavier" } 
		bias_filler	{ type: "constant" } 
	}
}
layer {
	name: "inc1_conv1_relu" 
	type: "ReLU" 
	bottom: "inc1_conv1" 
	top: "inc1_conv1" 	
}

layer {
	name: "inc1_conv2_1" 
	type: "Convolution" 
	bottom: "conv1" 
	top: "inc1_conv2_1" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 50 
		kernel_size: 3 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	}
}
layer {
	name: "inc1_conv2_1_relu" 
	type: "ReLU" 
	bottom: "inc1_conv2_1" 
	top:	"inc1_conv2_1" 
}

layer {
	name: "inc1_conv2_2"
	type: "Convolution" 
	bottom: "inc1_conv2_1" 
	top:	"inc1_conv2_2" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 50 
		kernel_size: 3 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler	{ type: "constant" } 
	}
}
layer {
	name: "inc1_conv2_2_relu" 
	type: "ReLU" 
	bottom: "inc1_conv2_2" 
	top: "inc1_conv2_2" 
}

layer {
	name: "inc1_conv2_3" 
	type: "Convolution" 
	bottom: "inc1_conv2_2" 
	top:	"inc1_conv2_3" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 50 
		kernel_size: 3 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	}
}
layer {
	name: "inc1_conv2_3_relu" 
	type: "ReLU" 
	bottom: "inc1_conv2_3" 
	top:	"inc1_conv2_3" 
}

layer {
	name: "inc1_conv3_1" 
	type: "Convolution" 
	bottom: "conv1" 
	top:	"inc1_conv3_1"
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 20 
		kernel_size: 5 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	}
}
layer {
	name: "inc1_conv3_1_relu" 
	type: "ReLU" 
	bottom: "inc1_conv3_1" 
	top: "inc1_conv3_1" 
}

layer {
	name: "inc1_conv3_2" 
	type: "Convolution" 
	bottom: "inc1_conv3_1" 
	top:	"inc1_conv3_2" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 20 
		kernel_size: 3 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	}
}
layer {
	name: "inc1_conv3_2_relu" 
	type: "ReLU" 
	bottom: "inc1_conv3_2" 
	top:	"inc1_conv3_2" 
}

layer {
	name: "inc1_concat" 
	type: "Concat" 
	bottom: "inc1_conv1" 
	bottom: "inc1_conv2_3" 
	bottom: "inc1_conv3_2" 
	top: 	"inc1_concat" 
}

#-----end of Inception 3a 

layer {
	name: "pool1" 
	type: "Pooling"
	bottom: "inc1_concat" 
	top: "pool1" 
	pooling_param {
		pool: MAX 
		kernel_size: 2 
		stride: 2 
	}
}


##------
# Inception 2B 
##------

layer {
	name: "inc2_conv1_1" 
	type: "Convolution" 
	bottom: "pool1" 
	top: "inc2_conv1_1" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 120 
		kernel_size: 3 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	}
}
layer {
	name: "inc2_conv1_1_relu" 
	type: "ReLU" 
	bottom: "inc2_conv1_1" 
	top: "inc2_conv1_1" 
}

layer {
	name: "inc2_conv1_2" 
	type: "Convolution" 
	bottom: "inc2_conv1_1" 
	top:	"inc2_conv1_2" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 120 
		kernel_size: 3 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	} 
}
layer {
	name: "inc2_conv1_2_relu"
	type: "ReLU"  
	bottom: "inc2_conv1_2" 
	top: "inc2_conv1_2" 
}

layer {
	name: "inc2_conv2" 
	type: "Convolution" 
	bottom: "pool1" 
	top:	"inc2_conv2" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	convolution_param {
		num_output: 120 
		kernel_size: 5 
		stride: 1 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	}
}
layer {
	name: "inc2_conv2_relu" 
	type: "ReLU" 
	bottom: "inc2_conv2" 
	top:	"inc2_conv2" 
}

layer {
	name: "inc2_concat" 
	type: "Concat" 
	bottom: "inc2_conv1_2" 
	bottom: "inc2_conv2" 
	top: "inc2_concat" 
}

##----end of Inception 2B 

layer {
	name: "pool2" 
	type: "Pooling" 
	bottom: "inc2_concat" 
	top:	"pool2" 
	pooling_param {
		pool: MAX 
		kernel_size: 2 
		stride: 2 
	}
}

layer {
	name: "fc1" 
	type: "InnerProduct" 
	bottom: "pool2" 
	top:	"fc1" 
	param { lr_mult: 1 } 
	param { lr_mult: 2 } 
	inner_product_param {
		num_output: 2 
		weight_filler { type: "xavier" } 
		bias_filler { type: "constant" } 
	}
}

#### ----------


layer {
	name: "prob" 
	type: "Softmax" 
	bottom: "fc1" 
	top: "prob" 
}

  

取得的效果比论文中的网络结构差点, 训练结果是:

I0927 00:11:42.485725 20295 solver.cpp:317] Iteration 10000, loss = 0.0678897
I0927 00:11:42.485771 20295 solver.cpp:337] Iteration 10000, Testing net (#0)
I0927 00:12:06.291497 20295 solver.cpp:404]     Test net output #0: accuracy = 0.8448
I0927 00:12:06.291554 20295 solver.cpp:404]     Test net output #1: loss = 0.614111 (* 1 = 0.614111 loss)
I0927 00:12:06.291563 20295 solver.cpp:322] Optimization Done.
I0927 00:12:06.291568 20295 caffe.cpp:254] Optimization Done.

  

实验分析:

因为该网络的组成较为复杂, inception包含着较大的子网络, 因为训练的时候,需要消耗GPU显存为3G多。训练时间也较长些。

 

reference:  

Learned vs. Hand-Crafted Features for Pedestrian Gender Recognition   Grigory Antipov,Sid-Ahmed Berrani