Private Detector
This is the repo for Bumble's Private Detectorβ’ model - an image classifier that can detect lewd images.
The internal repo has been heavily refactored and released as a fully open-source project to allow for the wider community to use and finetune a Private Detector model of their own. You can download the pretrained SavedModel, Frozen Model and checkpoint here
Model
The SavedModel can be found in saved_model/
within private_detector.zip
above
The model is based on Efficientnet-v2 and trained on our internal dataset of lewd images - more information can be found at the whitepaper here or here
Inference
Inference is pretty simple and an example has been given in inference.py
. The model is released as a SavedModel so it can be deployed in many different ways, but here's a quick runthrough of one way to get it working for those less familiar with Python/Tensorflow.
First you need to install Python and Conda on your system and go to the Terminal/Command Prompt on your machine
Then you can use the environment.yaml
file to install the necessary packages to run the inference.
conda env create -f environment.yaml
conda activate private_detector
Once that's set up, you can run the inference script. Simply replace the sample .jpg
file paths below with your own
python3 inference.py \
--model saved_model/ \
--image_paths \
Yes_samples/1.jpg \
Yes_samples/2.jpg \
Yes_samples/3.jpg \
Yes_samples/4.jpg \
Yes_samples/5.jpg \
No_samples/1.jpg \
No_samples/2.jpg \
No_samples/3.jpg \
No_samples/4.jpg \
No_samples/5.jpg \
Sample Output
Probability: 93.71% - Yes_samples/1.jpg
Probability: 93.43% - Yes_samples/2.jpg
Probability: 94.06% - Yes_samples/3.jpg
Probability: 94.08% - Yes_samples/4.jpg
Probability: 91.01% - Yes_samples/5.jpg
Probability: 9.76% - No_samples/1.jpg
Probability: 7.14% - No_samples/2.jpg
Probability: 8.83% - No_samples/3.jpg
Probability: 4.87% - No_samples/4.jpg
Probability: 5.29% - No_samples/5.jpg
Additional Training
You can finetune the model yourself on your own data, to do so is fairly simple - though you will need the checkpoint files as can be found in saved_checkpoint/
in private_detector.zip
Set up a JSON file with links to your image path lists for each class:
{
"Yes": {
"path": "/home/sofarrell/private_detector/Yes.txt",
"label": 0
},
"No": {
"path": "/home/sofarrell/private_detector/No.txt",
"label": 1
}
}
With each .txt
file listing off the image paths to your images
/home/sofarrell/private_detector_images/Yes/1093840880_309463828.jpg
/home/sofarrell/private_detector_images/Yes/657954182_3459624.jpg
/home/sofarrell/private_detector_images/Yes/1503714421_3048734.jpg
You can create the training environment with conda:
conda env create -f environment.yaml
conda activate private_detector
And then retrain like so:
python3 ./train.py \
--train_json /home/sofarrell/private_detector/train_classes.json \
--eval_json /home/sofarrell/private_detector/eval_classes.json \
--checkpoint_dir saved_checkpoint/ \
--train_id retrained_private_detector
The training script has several parameters that can be tweaked:
Command | Description | Type | Default |
---|---|---|---|
train_id |
ID for this particular training run | str | |
train_json |
JSON file(s) which describes classes and contains lists of filenames of data files | List[str] | |
eval_json |
Validation json file which describes classes and contains lists of filenames of data files | str | |
num_epochs |
Number of epochs to train for | int | |
batch_size |
Number of images to process in a batch | int | 64 |
checkpoint_dir |
Directory to store checkpoints in | str | |
model_dir |
Directory to store graph in | str | . |
data_format |
Data format: [channels_first, channels_last] | str | channels_last |
initial_learning_rate |
Initial learning rate | float | 1e-4 |
min_learning_rate |
Minimal learning rate | float | 1e-6 |
min_eval_metric |
Minimal evaluation metric to start saving models | float | 0.01 |
float_dtype |
Float Dtype to use in image tensors: [16, 32] | int | 16 |
steps_per_train_epoch |
Number of steps per train epoch | int | 800 |
steps_per_eval_epoch |
Number of steps per evaluation epoch | int | 1 |
reset_on_lr_update |
Whether to reset to the best model after learning rate update | bool | False |
rotation_augmentation |
Rotation augmentation angle, value <= 0 disables it | float | 0 |
use_augmentation |
Add speckle, v0, random or color distortion augmentation | str | |
scale_crop_augmentation |
Resize image to the model's size times this scale and then randomly crop needed size | float | 1.4 |
reg_loss_weight |
L2 regularization weight | float | 0 |
skip_saving_epochs |
Do not save good checkpoint and update best metric for this number of the first epochs | int | 0 |
sequential |
Use sequential run over randomly shuffled filenames vs equal sampling from each class | bool | False |
eval_threshold |
Threshold above which to consider a prediction positive for evaluation | float | 0.5 |
epochs_lr_update |
Maximum number of epochs without improvement used to reset/decrease learning rate | int | 20 |