Video2frame is also an easy-to-use tool to extract frames from video.

Forwchen's vid2frame tool is great, but I am always confused by their parameters. At the same time, I also want to add something I need to the tool.

So I re-wrote the code. And now, it is a new wheel. It is hard to make a PR since I changed the code style.

1. Establish the environment

   We recommend using conda to establish the environment. Just using

   conda env create -f install/conda-environment.yml

   You can also do it manually. This project relays on the following packages:

   • Python
   • FFmpeg
   • Python packages (can be installed using pip install -r install/pip-requirements.txt)
     • h5py
     • lmdb
     • numpy
     • easydict
     • tqdm

2. Make the annotation json file

   The json file should like

   {
       "meta": {
           "class_num": 2,
           "class_name": [
               "class_1",
               "class_2"
           ]
       },
       "annotation": {
           "label1_abcdefg": {
               "path": "path/to/the/video/file_1.mp4",
               "class": 1
           },
           "label2_asdfghj": {
               "path": "path/to/the/video/file_2.mp4",
               "class": 2
           }
       }
   }

3. Extract frames using video2frame.py

   Examples

   • Using the default options:

     python video2frame.py dataset.json

   • Specify the output file name:

     python video2frame.py dataset.json --db_name my_dataset

   • Using lmdb rather than hdf5:

     python video2frame.py dataset.json --db_type LMDB

     or

     python video2frame.py dataset.json --db_name my_dataset.lmdb

   • Random clip 5 seconds:

     python video2frame.py dataset.json --duration 5.0

   • Get 3 video clips with a length of 5 seconds:

     python video2frame.py dataset.json --clips 3 --duration 5.0 

   • Resize the frames to 320x240:

     python video2frame.py dataset.json --resize_mode 1 --resize 320x240

   • Keep the aspect ration, and resize the shorter side to 320:

     python video2frame.py dataset.json --resize_mode 2 --resize S320

   • Keep the aspect ration, and resize the longer side to 240:

     python video2frame.py dataset.json --resize_mode 2 --resize L240

   • Extract 5 frames per second:

     python video2frame.py dataset.json --fps 5

   • Uniformly sample 16 frames per video:

     python video2frame.py dataset.json --sample_mode 1 --sample 16

   • Randomly sample 16 frames per video:

     python video2frame.py dataset.json --sample_mode 2 --sample 16

   • Use 16 threads to speed-up:

     python video2frame.py dataset.json --threads 16

   • Resize the frames to 320x240, extract one frame every two seconds, uniformly sample 32 frames per video, and using 20 threads:

     python video2frame.py dataset.json \
         --resize_mode 1 \ 
         --resize 320x240 \
         --fps 0.5 \
         --sample_mode 1 \
         --sample 32 \
         --threads 20

   All parameters

   usage: video2frame.py [-h] [--db_name DB_NAME]
                         [--db_type {LMDB,HDF5,FILE,PKL}] [--tmp_dir TMP_DIR]
                         [--clips CLIPS] [--duration DURATION]
                         [--resize_mode {0,1,2}] [--resize RESIZE] [--fps FPS]
                         [--sample_mode {0,1,2,3}] [--sample SAMPLE]
                         [--threads THREADS] [--keep]
                         annotation_file
   
   positional arguments:
     annotation_file       The annotation file, in json format
   
   optional arguments:
     -h, --help            show this help message and exit
     --db_name DB_NAME     The database to store extracted frames (default: None)
     --db_type {LMDB,HDF5,FILE,PKL}
                           Type of the database (default: HDF5)
     --tmp_dir TMP_DIR     Temporary folder (default: /tmp)
     --clips CLIPS         Num of clips per video (default: 1)
     --duration DURATION   Length of each clip (default: -1)
     --resize_mode {0,1,2}
                           Resize mode
                             0: Do not resize
                             1: 800x600: Resize to WxH
                             2: L600 or S600: keep the aspect ration and scale the longer/shorter side to s (default: 0)
     --resize RESIZE       Parameter of resize mode (default: None)
     --fps FPS             Sample the video at X fps (default: -1)
     --sample_mode {0,1,2,3}
                           Frame sampling options
                             0: Keep all frames
                             1: Uniformly sample n frames
                             2: Randomly sample n continuous frames
                             3: Randomly sample n frames
                             4: Sample 1 frame every n frames (default: 0)
     --sample SAMPLE       How many frames (default: None)
     --threads THREADS     Number of threads (default: 0)
     --keep                Do not delete temporary files at last (default: False)
   

1. video_folder_to_json.py

   A json generator where the videos are arranged in this way:

   root/swimming/xxx.mp4
   root/swimming/xxy.avi
   root/swimming/xxz.flv
   
   root/dancing/123.mkv
   root/dancing/nsdf3.webm
   root/dancing/asd932_.mov
   

2. something_to_json.py

   A json generator that converts the Something-Something dataset.

3. ucf101_to_json.py

   A json generator that converts the UCF101 dataset.

1. pytorch_skvideo_dataset.py

   Get frames using skvideo package, when training and evaluating. It is OKay when your batch size is small, and your CPUs are powerful enough.

2. pytorch_lmdb_video_dataset.py

   A PyTorch Dataset example to read LMDB dataset.

3. pytorch_hdf5_video_dataset.py

   A PyTorch Dataset example to read HDF5 dataset.

   ALWAYS ENSURE num_workers=0 OR num_workers=1 OF YOUR DATA LOADER.

4. pytorch_pkl_video_dataset.py

   A PyTorch Dataset example to read pickle dataset.

5. pytorch_file_video_dataset.py

   A PyTorch Dataset example to read image files dataset.