I am relatively new to machine learning/python/ubuntu.
I have a set of images in .jpg format where half contain a feature I want caffe to learn and half don't. I'm having trouble in finding a way to convert them to the required lmdb format.
I have the necessary text input files.
My question is can anyone provide a step by step guide on how to use convert_imageset.cpp
in the ubuntu terminal?
Thanks
convert_imageset
First thing you must do is build caffe and caffe's tools (convert_imageset
is one of these tools).
After installing caffe and make
ing it make sure you ran make tools
as well.
Verify that a binary file convert_imageset
is created in $CAFFE_ROOT/build/tools
.
Images: put all images in a folder (I'll call it here /path/to/jpegs/
).
Labels: create a text file (e.g., /path/to/labels/train.txt
) with a line per input image . For example:
img_0000.jpeg 1
img_0001.jpeg 0
img_0002.jpeg 0
In this example the first image is labeled 1
while the other two are labeled 0
.
Run the binary in shell
~$ GLOG_logtostderr=1 $CAFFE_ROOT/build/tools/convert_imageset \
--resize_height=200 --resize_width=200 --shuffle \
/path/to/jpegs/ \
/path/to/labels/train.txt \
/path/to/lmdb/train_lmdb
Command line explained:
GLOG_logtostderr
flag is set to 1 before calling convert_imageset
indicates the logging mechanism to redirect log messages to stderr. --resize_height
and --resize_width
resize all input images to same size 200x200
. --shuffle
randomly change the order of images and does not preserve the order in the /path/to/labels/train.txt
file. convert_imageset
otherwise you'll get a scary error message.Other flags that might be useful:
--backend
- allows you to choose between an lmdb
dataset or levelDB
.--gray
- convert all images to gray scale.--encoded
and --encoded_type
- keep image data in encoded (jpg/png) compressed form in the database.--help
- shows some help, see all relevant flags under Flags from tools/convert_imageset.cpp You can check out $CAFFE_ROOT/examples/imagenet/convert_imagenet.sh
for an example how to use convert_imageset
.