BNN v2

unet style image translation from image of hive entrance to bitmap of location of center of bees.

trained in a semi supervised way on a desktop gpu and deployed to run in real time on the hive using either a raspberry pi using a neural compute stick or a je vois embedded smart camera

see this blog post for more info..

here's an example of predicting bee position on some held out data. the majority of examples trained had ~10 bees per image.

the ability to locate each bee means you can summarise with a count. note the spike around 4pm when the bees at this time of year come back to base.

usage

gathering data

the rasp_pi sub directory includes one method of collecting images on a raspberry pi.

labelling

start by using the label_ui.py tool to manually label some images and create a sqlite label.db

the following command starts the labelling tool for some already labelled (by me!) sample data provided with in this repro.

./label_ui.py \
--image-dir sample_data/training/ \
--label-db sample_data/labels.db \
--width 768 --height 1024

hints

• left click to label the center of a bee
• right click to remove the closest label
• press up to toggle labels on / off. this can help in tricky cases.
• use left / right to move between images. it's often helpful when labelling to quickly switch back/forth between images to help distinguish background
• use whatever system your OS provides to zoom in; e.g. in ubuntu super+up / down

you can merge entries from a.db into b.db with merge_db.py

./merge_dbs.py --from-db a.db --to-db b.db

training

before training we materialise a label.db (which is a database of x,y coords) into black and white bitmaps using ./materialise_label_db.py

./materialise_label_db.py \
--label-db sample_data/labels.db \
--directory sample_data/labels/ \
--width 768 --height 1024

we can visualise the training data with data.py. this will generate a number of test*png files with the input data on the left (with data augmentation) and the output labels on the right.

./data.py \
--image-dir sample_data/training/ \
--label-dir sample_data/labels/ \
--width 768 --height 1024

train with train.py.

run denotes the subdirectory for ckpts and tensorboard logs; e.g. --run r12 checkpoints under ckpts/r12/ and logs under tb/r12.

use --help to get complete list of options including model config, defining validation data and stopping conditions.

e.g. to train for a short time on sample_data run the following... (for a more realistic result we'd want to train for many more steps on much more data)

./train.py \
--run r12 \
--steps 300 \
--train-steps 50 \
--train-image-dir sample_data/training/ \
--test-image-dir sample_data/test/ \
--label-dir sample_data/labels/ \
--width 768 --height 1024

progress can be visualised with tensorboard (serves at localhost:6006)

tensorboard --log-dir tb

inference

predictions can be run with predict.py. to specifiy what type of output set one of the following...

• --output-label-db to create a label db; this can be merged with a human labelled db, using ./merge_dbs.py for semi supervised learning
• --export-pngs centroids to export output bitmaps equivalent as those made by ./materialise_label_db.py
• --export-pngs predictions to export explicit model output (i.e. before connected components post processing)

NOTE: given the above step that only runs a short period on a small dataset we DON'T expect this to give a great result; these instructions are more included to prove the plumbing works...

./predict.py \
--run r12 \
--image-dir sample_data/unlabelled \
--output-label-db sample_predictions.db \
--export-pngs predictions

output predictions can be compared to labelled data to calculate precision recall. (we deem a detection correct if it is within a thresholded distance from a label)

./compare_label_dbs.py --true-db ground_truth.db --predicted-db predictions.db
precision 0.936  recall 0.797  f1 0.861

running on compute stick

( note: this still doesn't work; possibly because of something in these steps, or possibly something about the tf api support of the stick. see this forum post for more info... )

some available datasets

• Jonathan Byrne's to-bee-or-not-to-bee kaggle dataset