# Preparing Jester

## Introduction

<!-- [DATASET] -->

```BibTeX
@InProceedings{Materzynska_2019_ICCV,
  author = {Materzynska, Joanna and Berger, Guillaume and Bax, Ingo and Memisevic, Roland},
  title = {The Jester Dataset: A Large-Scale Video Dataset of Human Gestures},
  booktitle = {Proceedings of the IEEE/CVF International Conference on Computer Vision (ICCV) Workshops},
  month = {Oct},
  year = {2019}
}
```

For basic dataset information, you can refer to the dataset [website](https://developer.qualcomm.com/software/ai-datasets/jester).
Before we start, please make sure that the directory is located at `$MMACTION2/tools/data/jester/`.

## Step 1. Prepare Annotations

First of all, you have to sign in and download annotations to `$MMACTION2/data/jester/annotations` on the official [website](https://developer.qualcomm.com/software/ai-datasets/jester).

## Step 2. Prepare RGB Frames

Since the [jester website](https://developer.qualcomm.com/software/ai-datasets/jester) doesn't provide the original video data and only extracted RGB frames are available, you have to directly download RGB frames from [jester website](https://developer.qualcomm.com/software/ai-datasets/jester).

You can download all RGB frame parts on [jester website](https://developer.qualcomm.com/software/ai-datasets/jester) to `$MMACTION2/data/jester/` and use the following command to extract.

```shell
cd $MMACTION2/data/jester/
cat 20bn-jester-v1-?? | tar zx
cd $MMACTION2/tools/data/jester/
```

For users who only want to use RGB frames, you can skip to step 5 to generate file lists in the format of rawframes. Since the prefix of official JPGs is "%05d.jpg" (e.g., "00001.jpg"),
we add `"filename_tmpl='{:05}.jpg'"` to the dict of `data.train`, `data.val` and `data.test` in the config files related with jester like this:

```
data = dict(
    videos_per_gpu=16,
    workers_per_gpu=2,
    train=dict(
        type=dataset_type,
        ann_file=ann_file_train,
        data_prefix=data_root,
        filename_tmpl='{:05}.jpg',
        pipeline=train_pipeline),
    val=dict(
        type=dataset_type,
        ann_file=ann_file_val,
        data_prefix=data_root_val,
        filename_tmpl='{:05}.jpg',
        pipeline=val_pipeline),
    test=dict(
        type=dataset_type,
        ann_file=ann_file_test,
        data_prefix=data_root_val,
        filename_tmpl='{:05}.jpg',
        pipeline=test_pipeline))
```

## Step 3. Extract Flow

This part is **optional** if you only want to use RGB frames.

Before extracting, please refer to [install.md](/docs/en/get_started/installation.md) for installing [denseflow](https://github.com/open-mmlab/denseflow).

If you have plenty of SSD space, then we recommend extracting frames there for better I/O performance.

You can run the following script to soft link SSD.

```shell
# execute these two line (Assume the SSD is mounted at "/mnt/SSD/")
mkdir /mnt/SSD/jester_extracted/
ln -s /mnt/SSD/jester_extracted/ ../../../data/jester/rawframes
```

Then, you can run the following script to extract optical flow based on RGB frames.

```shell
cd $MMACTION2/tools/data/jester/
bash extract_flow.sh
```

## Step 4. Encode Videos

This part is **optional** if you only want to use RGB frames.

You can run the following script to encode videos.

```shell
cd $MMACTION2/tools/data/jester/
bash encode_videos.sh
```

## Step 5. Generate File List

You can run the follow script to generate file list in the format of rawframes and videos.

```shell
cd $MMACTION2/tools/data/jester/
bash generate_{rawframes, videos}_filelist.sh
```

## Step 5. Check Directory Structure

After the whole data process for Jester preparation,
you will get the rawframes (RGB + Flow), and annotation files for Jester.

In the context of the whole project (for Jester only), the folder structure will look like:

```
mmaction2
├── mmaction
├── tools
├── configs
├── data
│   ├── jester
│   │   ├── jester_{train,val}_list_rawframes.txt
│   │   ├── jester_{train,val}_list_videos.txt
│   │   ├── annotations
│   |   ├── videos
│   |   |   ├── 1.mp4
│   |   |   ├── 2.mp4
│   |   |   ├──...
│   |   ├── rawframes
│   |   |   ├── 1
│   |   |   |   ├── 00001.jpg
│   |   |   |   ├── 00002.jpg
│   |   |   |   ├── ...
│   |   |   |   ├── flow_x_00001.jpg
│   |   |   |   ├── flow_x_00002.jpg
│   |   |   |   ├── ...
│   |   |   |   ├── flow_y_00001.jpg
│   |   |   |   ├── flow_y_00002.jpg
│   |   |   |   ├── ...
│   |   |   ├── 2
│   |   |   ├── ...

```

For training and evaluating on Jester, please refer to [Training and Test Tutorial](/docs/en/user_guides/train_test.md).