import?operator
import?numpy?as?np
import?os
from?PIL?import?Image


class?PCAtest（）:
????def?__init__（self?d）:#d表示所降維度
????????self.d?=?d

????def?train（self?X）:
????????X?=?np.array（X?dtype=“float64“）
????????X?=?self.normalize（X）
????????cov_matrix_t?=?X.T.dot（X）
????????eigen_values?eigen_vectors?=?np.linalg.eig（cov_matrix_t）
????????eigen_values?=?eigen_values.tolist（）
????????eigen_vectors?=?X.dot（eigen_vectors）
????????eigen_vectors?=?eigen_vectors.T.tolist（）
????????eigen_zip?=?[（value.real?vector）?for?value?vector?in?zip（eigen_values?eigen_vectors）]
????????print（“len?of?real?eigen?values“?len（eigen_zip））
????????orderd_eigens?=?sorted（eigen_zip?key=operator.itemgetter（0）?reverse=True）
????????self.max_eigen_vectors?=?[orderd_eigens[i][1]?for?i?in?range（self.d）]
????????self.W?=?np.real（np.array（self.max_eigen_vectors）.T）
????????self.W?/=?np.sqrt（np.sum（self.W?**?2?axis=0?keepdims=True））

????def?normalize（self?X）:#標準化
????????self.mean_vector?=?1.0?/?X.shape[1]?*?np.sum（X?axis=1?keepdims=True）
????????self.std?=?np.std（X?axis=1?keepdims=True）?+?10e-8
????????X?=?（X?-?self.mean_vector）
????????return?X

????def?dim_reduction（self?x）:#降維處理
????????return?self.W.T.dot（x）

????def?construct（self?c）:#數據構造
????????new?=?self.W.dot（c）
????????return?（new）


def?main（）:
????imgName?=?[‘subject03.wink‘?‘subject08.happy‘?‘subject14.surprised‘]#所選圖片
????K?=?[20?100]#所降維數
????for?i?in?K:
????????for?j?in?imgName:
????????????d?=?i
????????????path?=?“yalefaces“
????????????X?=?[]
????????????n?=?1
????????????for?file?in?os.listdir（path）:
????????????????if?not?file.endswith（“.txt“）:
????????????????????img?=?Image.open（os.path.join（path?file））
????????????????????img?=?np.array（img）.reshape（img.width?*?img.height）
????????????????????X.append（img）
????????????????????n?+=?1
????????????X?=?np.array（X）
????????????X?=?X.T
????????????pca?=?PCAtest（d）
????????????pca.train（X）
????????????img?=?Image.open（os.path.join（path?j））
????????????w?h?=?img.width?img.height
????????????img?=?np.array（img）.reshape（w?*?h?1）
????????????img?=?img?-?pca.mean_vector
????????????features?=?pca.dim_reduction（img）
????????????x_hat?=?pca.construct（features）
????????????x_hat?+=?pca.mean_vector
????????????x_hat?=?x_hat.reshape（h?w）
????????????x_hat?=?np.array（x_hat?dtype=“int32“）
????????????new_img?=?Image.fromarray（x_hat）.convert（‘L‘）
????????????new_file?=?j?+?str（i）?+?‘.png‘
????????????new_img.save（os.path.join（‘yalefaces‘?new_file））

if?__name__?==?“__main__“:
????main（）

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????2656??2018-12-16?15:21??PCA_yale人臉數據集\test.py

?????文件???????1172??2018-12-16?14:14??PCA_yale人臉數據集\yalefaces\Readme.txt

?????文件??????35413??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.gif

?????文件??????36294??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.glasses

?????文件??????36294??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.glasses.gif

?????文件??????36692??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.happy

?????文件??????42921??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.leftlight

?????文件??????34100??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.noglasses

?????文件??????36129??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.normal

?????文件??????71627??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.rightlight

?????文件??????36370??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.sad

?????文件??????36307??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.sleepy

?????文件??????36647??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.surprised

?????文件??????36381??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject01.wink

?????文件??????31137??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.centerlight

?????文件??????45239??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.glasses

?????文件??????43765??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.happy

?????文件??????38159??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.leftlight

?????文件??????43681??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.noglasses

?????文件??????43681??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.normal

?????文件??????62924??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.rightlight

?????文件??????43439??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.sad

?????文件??????43518??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.sleepy

?????文件??????45447??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.surprised

?????文件??????43080??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject02.wink

?????文件??????26833??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject03.centerlight

?????文件??????27292??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject03.glasses

?????文件??????28032??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject03.happy

?????文件??????34932??1997-04-06?16:06??PCA_yale人臉數據集\yalefaces\subject03.leftlight

?????文件??????27895??1997-04-06?16:07??PCA_yale人臉數據集\yalefaces\subject03.noglasses

............此處省略143個文件信息