About

Implementation of:
Du Tran, Lubomir Bourdev, Rob Fergus, Lorenzo Torresani, Manohar Paluri Learning Spatiotemporal Features With 3D Convolutional Networks. Proceedings of the IEEE International Conference on Computer Vision. 2015. full article

Updated to keras 2.2.4

Weights

You can download weights of the model trained on the original dataset (Sport_1M) here:
https://drive.google.com/file/d/1rlZ-xTkTMjgWKiQFUedRnHlDgQwx6yTm/view

To run the c3d/example.py you should place them in a models directory or change the path inside the example.py accordingly.

The weights were converted from the Caffe format with the code and instructions in this project:
https://github.com/axon-research/c3d-keras

How to run

1. Build a docker image:
   Run make build from the top directory.

2. Check if everything works:
   Run make example from the top directory.

You should see this message if everything is ok:

Model's architecture

Layer (type)                 Output Shape              Param #   
=================================================================
input_2 (InputLayer)         (None, 16, 112, 112, 3)   0         
_________________________________________________________________
conv1 (Conv3D)               (None, 16, 112, 112, 64)  5248      
_________________________________________________________________
pool1 (MaxPooling3D)         (None, 16, 56, 56, 64)    0         
_________________________________________________________________
conv2 (Conv3D)               (None, 16, 56, 56, 128)   221312    
_________________________________________________________________
pool2 (MaxPooling3D)         (None, 8, 28, 28, 128)    0         
_________________________________________________________________
conv3a (Conv3D)              (None, 8, 28, 28, 256)    884992    
_________________________________________________________________
conv3b (Conv3D)              (None, 8, 28, 28, 256)    1769728   
_________________________________________________________________
pool3 (MaxPooling3D)         (None, 4, 14, 14, 256)    0         
_________________________________________________________________
conv4a (Conv3D)              (None, 4, 14, 14, 512)    3539456   
_________________________________________________________________
conv4b (Conv3D)              (None, 4, 14, 14, 512)    7078400   
_________________________________________________________________
pool4 (MaxPooling3D)         (None, 2, 7, 7, 512)      0         
_________________________________________________________________
conv5a (Conv3D)              (None, 2, 7, 7, 512)      7078400   
_________________________________________________________________
conv5b (Conv3D)              (None, 2, 7, 7, 512)      7078400   
_________________________________________________________________
zeropad5 (ZeroPadding3D)     (None, 2, 8, 8, 512)      0         
_________________________________________________________________
pool5 (MaxPooling3D)         (None, 1, 4, 4, 512)      0         
_________________________________________________________________
flatten_2 (Flatten)          (None, 8192)              0         
_________________________________________________________________
fc6 (Dense)                  (None, 4096)              33558528  
_________________________________________________________________
dropout_1 (Dropout)          (None, 4096)              0         
_________________________________________________________________
fc7 (Dense)                  (None, 4096)              16781312  
_________________________________________________________________
dropout_2 (Dropout)          (None, 4096)              0         
_________________________________________________________________
fc8 (Dense)                  (None, 487)               1995239   
=================================================================
Total params: 79,991,015
Trainable params: 79,991,015
Non-trainable params: 0

Features extraction

To extract features from a video you should:

1. Divide a video into 16 frame chunks with 8 frame overlaps (dim=(16, 112, 112, 3)).
2. Use output from the first fully connected layer fc6 as a features from the single chunk. (implemented in sport1m_model.create_features_exctractor)
3. Average features extracted from all vectors to form a single vector (dim=4096).
4. L2-normalize the vector.

Note: Authors used 2 seconds clips during training.