/usr/include/dlib/entropy_encoder/ is in libdlib-dev 18.18-2build1.
This file is owned by root:root, with mode 0o755.
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/usr/include/dlib/entropy_encoder/entropy_encoder_kernel_1.h
/usr/include/dlib/entropy_encoder/entropy_encoder_kernel_2.h
/usr/include/dlib/entropy_encoder/entropy_encoder_kernel_abstract.h
/usr/include/dlib/entropy_encoder/entropy_encoder_kernel_c.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_1.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_2.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_3.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_4.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_5.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_6.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_abstract.h
/usr/include/dlib/entropy_encoder_model/entropy_encoder_model_kernel_c.h