Error in building mean image file(Caffe)

Question

I am trying to do classification of digits(mnist). I need to make an mean image file from the lmdb data to use it for testing(classification) on an image of a digit. So I am trying to use the compute_image_mean to build the mean image file but I am getting the following error below.

F1219 12:45:42.852679  6189 db_lmdb.hpp:15] Check failed: mdb_status == 0 (20 vs. 0) Not a directory
*** Check failure stack trace: ***
@     0x7f4c092bbdaa  (unknown)
@     0x7f4c092bbce4  (unknown)
@     0x7f4c092bb6e6  (unknown)
@     0x7f4c092be687  (unknown)
@     0x7f4c097a1291  caffe::db::LMDB::Open()
@           0x402044  main
@     0x7f4c082c7f45  (unknown)
@           0x402a8a  (unknown)
@              (nil)  (unknown)
Aborted (core dumped)

Command used- ./../build/tools/compute_image_mean ./data/train.mdb ./mean.binaryproto

Is this the correct way to generate a mean image file?

caffe users group link

Answer 1

As DB path you only need to supply the path to the DB folder, and not the db itself.
Try:

 ./../build/tools/compute_image_mean ./data/ ./mean.binaryproto