FILM: Frame Interpolation for Large Motion

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About frame-interpolation-tflite-unity fork

The aim of this fork is to use FILM model on Unity for frame interpolation. It is based on asus4/tf-lite-unity-sample and uses TensorFlow Lite to perform the operations. Make sure to check the compatibility of this library with respect to your target device. It is the following as of writing this text:

	iOS	Android	macOS	Ubuntu	Windows
Core CPU	✅	✅	✅	✅	✅
Metal Delegate	✅	-	✅	-	-
GPU Delegate	-	✅	-	✅ Experimental	-
NNAPI Delegate	-	✅	-	-	-

TFLite Model

The pretrained model given in the project is converted to the .tflite format. You may use it for other projects and purposes too. Unfortunately, I was not able to make it GPU delegate compatible.

You may perform the conversion operation yourself.

--

Here are the shapes required for inference:

// IT: Input Tensor
// OT: Output Tensor

(1, 1)[[0.5]] -> IT[0]      // Time parameter, it is always inferred a frame at t = 0.5 (interpolator.py#L102)
(1, WIDTH, HEIGHT, 3) -> IT[1]      // Input image 1
(1, WIDTH, HEIGHT, 3) -> IT[2]      // Input image 2
.
.
.
OT[1] -> (1, WIDTH, HEIGHT, 3)      // Output image, retrieved from index 1 of OT

For the Unity project, download and place the .tflite file in the StreamingAssets folder.

PS: I also tried converting to .onnx format using tf2onnx using multiple opsets to make it compatible with Barracuda, however, I could not get it to work due to some uncompatible operations, such as this one. Feel free to create an issue/PR if you manage to make it work.

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About the project

The official Tensorflow 2 implementation of our high quality frame interpolation neural network. We present a unified single-network approach that doesn't use additional pre-trained networks, like optical flow or depth, and yet achieve state-of-the-art results. We use a multi-scale feature extractor that shares the same convolution weights across the scales. Our model is trainable from frame triplets alone.

FILM: Frame Interpolation for Large Motion
Fitsum Reda¹, Janne Kontkanen¹, Eric Tabellion¹, Deqing Sun¹, Caroline Pantofaru¹, Brian Curless^1,2
1Google Research, ²University of Washington
In ECCV 2022.

FILM transforms near-duplicate photos into a slow motion footage that look like it is shot with a video camera.

Web Demo

Integrated into Hugging Face Spaces 🤗 using Gradio. Try out the Web Demo:

Try the interpolation model with the replicate web demo at

Try FILM to interpolate between two or more images with the PyTTI-Tools at

An alternative Colab for running FILM on arbitrarily more input images, not just on two images,

Change Log

• Nov 28, 2022: Upgrade eval.interpolator_cli for high resolution frame interpolation. --block_height and --block_width determine the total number of patches (block_height*block_width) to subdivide the input images. By default, both arguments are set to 1, and so no subdivision will be done.
• Mar 12, 2022: Support for Windows, see WINDOWS_INSTALLATION.md.
• Mar 09, 2022: Support for high resolution frame interpolation. Set --block_height and --block_width in eval.interpolator_test to extract patches from the inputs, and reconstruct the interpolated frame from the iteratively interpolated patches.

Installation

• Get Frame Interpolation source codes

git clone https://github.com/google-research/frame-interpolation
cd frame-interpolation

• Optionally, pull the recommended Docker base image

docker pull gcr.io/deeplearning-platform-release/tf2-gpu.2-6:latest

• If you do not use Docker, set up your NVIDIA GPU environment with:

  • Anaconda Python 3.9
  • CUDA Toolkit 11.2.1
  • cuDNN 8.1.0

• Install frame interpolation dependencies

pip3 install -r requirements.txt
sudo apt-get install -y ffmpeg

See WINDOWS_INSTALLATION for Windows Support

Pre-trained Models

• Create a directory where you can keep large files. Ideally, not in this directory.

mkdir -p <pretrained_models>

• Download pre-trained TF2 Saved Models from google drive and put into <pretrained_models>.

The downloaded folder should have the following structure:

<pretrained_models>/
├── film_net/
│   ├── L1/
│   ├── Style/
│   ├── VGG/
├── vgg/
│   ├── imagenet-vgg-verydeep-19.mat

Running the Codes

The following instructions run the interpolator on the photos provided in 'frame-interpolation/photos'.

One mid-frame interpolation

To generate an intermediate photo from the input near-duplicate photos, simply run:

python3 -m eval.interpolator_test \
   --frame1 photos/one.png \
   --frame2 photos/two.png \
   --model_path <pretrained_models>/film_net/Style/saved_model \
   --output_frame photos/output_middle.png

This will produce the sub-frame at t=0.5 and save as 'photos/output_middle.png'.

Many in-between frames interpolation

It takes in a set of directories identified by a glob (--pattern). Each directory is expected to contain at least two input frames, with each contiguous frame pair treated as an input to generate in-between frames. Frames should be named such that when sorted (naturally) with natsort, their desired order is unchanged.

python3 -m eval.interpolator_cli \
   --pattern "photos" \
   --model_path <pretrained_models>/film_net/Style/saved_model \
   --times_to_interpolate 6 \
   --output_video

You will find the interpolated frames (including the input frames) in 'photos/interpolated_frames/', and the interpolated video at 'photos/interpolated.mp4'.

The number of frames is determined by --times_to_interpolate, which controls the number of times the frame interpolator is invoked. When the number of frames in a directory is num_frames, the number of output frames will be (2^times_to_interpolate+1)*(num_frames-1).

Datasets

We use Vimeo-90K as our main training dataset. For quantitative evaluations, we rely on commonly used benchmark datasets, specifically:

• Vimeo-90K
• Middlebury-Other
• UCF101
• Xiph

Creating a TFRecord

The training and benchmark evaluation scripts expect the frame triplets in the TFRecord storage format.

We have included scripts that encode the relevant frame triplets into a tf.train.Example data format, and export to a TFRecord file.

You can use the commands python3 -m datasets.create_<dataset_name>_tfrecord --help for more information.

For example, run the command below to create a TFRecord for the Middlebury-other dataset. Download the images and point --input_dir to the unzipped folder path.

python3 -m datasets.create_middlebury_tfrecord \
  --input_dir=<root folder of middlebury-other> \
  --output_tfrecord_filepath=<output tfrecord filepath> \
  --num_shards=3

The above command will output a TFRecord file with 3 shards as <output tfrecord filepath>@3.

Training

Below are our training gin configuration files for the different loss function:

training/
├── config/
│   ├── film_net-L1.gin
│   ├── film_net-VGG.gin
│   ├── film_net-Style.gin

To launch a training, simply pass the configuration filepath to the desired experiment.
By default, it uses all visible GPUs for training. To debug or train on a CPU, append --mode cpu.

python3 -m training.train \
   --gin_config training/config/<config filename>.gin \
   --base_folder <base folder for all training runs> \
   --label <descriptive label for the run>

• When training finishes, the folder structure will look like this:

<base_folder>/
├── <label>/
│   ├── config.gin
│   ├── eval/
│   ├── train/
│   ├── saved_model/

Build a SavedModel

Optionally, to build a SavedModel format from a trained checkpoints folder, you can use this command:

python3 -m training.build_saved_model_cli \
   --base_folder <base folder of training sessions> \
   --label <the name of the run>

• By default, a SavedModel is created when the training loop ends, and it will be saved at <base_folder>/<label>/saved_model.

Evaluation on Benchmarks

Below, we provided the evaluation gin configuration files for the benchmarks we have considered:

eval/
├── config/
│   ├── middlebury.gin
│   ├── ucf101.gin
│   ├── vimeo_90K.gin
│   ├── xiph_2K.gin
│   ├── xiph_4K.gin

To run an evaluation, simply pass the configuration file of the desired evaluation dataset.
If a GPU is visible, it runs on it.

python3 -m eval.eval_cli \
   --gin_config eval/config/<eval_dataset>.gin \
   --model_path <pretrained_models>/film_net/L1/saved_model

The above command will produce the PSNR and SSIM scores presented in the paper.

Citation

If you find this implementation useful in your works, please acknowledge it appropriately by citing:

@inproceedings{reda2022film,
 title = {FILM: Frame Interpolation for Large Motion},
 author = {Fitsum Reda and Janne Kontkanen and Eric Tabellion and Deqing Sun and Caroline Pantofaru and Brian Curless},
 booktitle = {European Conference on Computer Vision (ECCV)},
 year = {2022}
}

@misc{film-tf,
  title = {Tensorflow 2 Implementation of "FILM: Frame Interpolation for Large Motion"},
  author = {Fitsum Reda and Janne Kontkanen and Eric Tabellion and Deqing Sun and Caroline Pantofaru and Brian Curless},
  year = {2022},
  publisher = {GitHub},
  journal = {GitHub repository},
  howpublished = {\url{https://github.com/google-research/frame-interpolation}}
}

Acknowledgments

We would like to thank Richard Tucker, Jason Lai and David Minnen. We would also like to thank Jamie Aspinall for the imagery included in this repository.

Coding style

• 2 spaces for indentation
• 80 character line length
• PEP8 formatting

Disclaimer

This is not an officially supported Google product.