The stop action movie recorder and player are two command line python scripts for creating stop action movies. As the name implies, stop_action_recorder.py is used to record the movie and stop_action_player.py is used to play the movie.
stop_action_recorder.py uses the specified webcam to record the movie. Upon start up, the program will capture an frame and display a live view of what is visible on the webcam. When the SPACE key is pressed, the frame will be saved. That image will be shown as a faint image behind the live image for reference as the next frame is being prepared.
These keys have the following functions:
Space Saves a frame
G or g Toggles the display of the grid from on to off or visa versa
ESC Exits the program.
The frames are stored as .png files with names in the form of filename.nnn.png where filename is the name provided to the command and nnn is the number of the frame. For example: testmovie.002.png.
An additional file named filename.count containing the number of frames in the movie is also created. For example: testmovie.count. This file is used by stop_action_player.py to play the movie.
The frame and .count files are stored in the current directory.
stop_action_player.py uses the files created by stop_action_recorder.py to play back the movie. The movie will be played until the ESC key is pressed. The time between frames can be specified on the command line; the default is 0.1 seconds.
When the movie is played, the frame numbers and frames per second (fps) are displayed in the upper left corner of the screen. The display of the frame numbers and fps can be suppressed using the -s or --suspressframetext options on the command line. The frame numbers and fps can be toggled on and off by pressing the f key while the movie is playing.
make_mpeg.py uses the files created by stop_action_recorder.py to create a .mp4 video.
delete_frame_set.py will delete all the files associated with a movie created by stop_action_recorder.py.
repeat_first_frame.py will add extra first frames to the beginning of the movie. This makes the first frame display longer when playing the movie with stop_action_player.py or when making a mp4 with make_mpeg.py.
repeat_last_frame.py will add extra last frames to the end of the movie. This makes the last frame display longer when playing the movie with stop_action_player.py or when making a mp4 with make_mpeg.py.
The stop action movie recorder, player, and the mpeg maker are written for python 2.7.x.
$ stop_action_recorder.py -h
usage: stop_action_recorder.py [-h] [-d] [-g] [-s GRIDSPACING]
[-w WEBCAMNUMBER] [-r] [-a ALPHAVALUE]
movie_name
Stop action movie recorder
positional arguments:
movie_name file name of the stop action movie
optional arguments:
-h, --help show this help message and exit
-d, --debug display debugging messages
-g, --gridlines display grid lines
-s GRIDSPACING, --spacing GRIDSPACING
grid spacing (pixels)
-w WEBCAMNUMBER, --webcam WEBCAMNUMBER
number of the webcam to use
-r, --reverseimages reverses the foreground and background images
-a ALPHAVALUE, --alpha ALPHAVALUE
alpha value for the background image
valid values are 0.0 to 1.0
default is 0.65
Record a movie using webcam 0 and store the frames in files with the name testmovie.
$ python stop_action_recorder.py testmovie
Record a movie using webcam 1 and store the frames in files with the name testmovie.
$ python stop_action_recorder.py testmovie -w 1
Record a movie using webcam 0, display grid lines and space them 25 pixels apart. Note: display of grid lines can be turned on or off from the keyboard by pressing the g key.
$ python stop_action_recorder.py testmovie -g -s 25
Record a movie using webcam 0 and store the frames in files with the name testmovie. When displaying the images make the live frames fainter than and the previous frame.
$ python stop_action_recorder.py testmovie -r
Record a movie using webcam 0 and store the frames in files with the name testmovie using an alpha value of 0.50 for the background image.
$ python stop_action_recorder.py testmovie -a 0.50
Record a movie using webcam 0 and store the frames in files with the name testmovie. When displaying the images make the live frames fainter than and the previous frame and an alpha value of 0.50
$ python stop_action_recorder.py testmovie -r -a 0.50
If stop_action_recorder.py is unable to open the webcam, it will display the message:
cannot open webcam
If stop_action_recorder.py is unable to capture the initial frame, it will display the following message and exit.
unable to read initial webcam image
If stop_action_recorder.py is unable to capture a subsequent frame, it will display the following message and exit.
unable to read webcam image in loop
$ python stop_action_player.py -h
usage: stop_action_player.py [-h] [-f FRAMESPERSECOND] [-s] [-d] [-b]
[-a FIRSTFRAMEREPEAT] [-z LASTFRAMEREPEAT]
movie_name
Stop action movie player
positional arguments:
movie_name file name of the stop action movie
optional arguments:
-h, --help show this help message and exit
-f FRAMESPERSECOND, --FPS FRAMESPERSECOND
frames per second
-s, --suppressframenumbers
suppress display of frame numbers
-d, --debug display debugging messages
-b, --playbackwards play the movie backwards
-a FIRSTFRAMEREPEAT, --firstframerepeat FIRSTFRAMEREPEAT
number of times to repeat the first frame on playback
-z LASTFRAMEREPEAT, --lastframerepeat LASTFRAMEREPEAT
number of times to repeat the last frame on playback
Play a movie named testmovie using the default of tens frames per second.
$ python stop_action_player.py testmovie
Play a movie named testmovie using the default of tens frames per second and play it backwards (frames played in the opposite order that it was recorded).
$ python stop_action_player.py testmovie -b
Play a movie named testmovie using the default of ten frames per second and play frame 001 ten times (this allows the first frame to be visible longer which is good for the beginning or end of the movie if -b is also specified.
$ python stop_action_player.py testmovie -a 10
Play a movie named testmovie using the default of ten frames per second and play the last frame twenty times (this allows the first frame to be visible longer which is good for the beginning or end of the movie if -b is also specified.
$ python stop_action_player.py testmovie -z 20
Play a movie named testmovie at 20 frames per second.
$ python stop_action_player.py testmovie -f 20
Play a movie named testmovie and suppress the display of the frame numbers. Note: the display of frame numbers can be toggled on and off by pressing the f key while the movie is playing.
$ python stop_action_player.py testmovie -s
If stop_action_player.py is unable to open the frame count file, it will display a message like the one below and exit:
can not open frame count file testmovie.count
If stop_action_player.py is unable to open one of the frame files, it will display a message like the one below and exit:
frame file testmovie.001.png does not exist
If frames per second are specified as a negative number or zero, the following message will be displayed and the program will exit:
frames per second must be one or higher
If the movie has too few frames, the following message will be displayed and the program will exit:
movie must contain at least two frames
$ python make_mpeg.py -h
usage: make_mpeg.py [-h] [-f FPS] [-s] [-b] input_file output_file
Stop action mpeg movie maker
positional arguments:
input_file input file name
output_file output file name
optional arguments:
-h, --help show this help message and exit
-f FPS, --fps FPS frames per second, default is 2 fps
-s, --silent if specified, do not display messages
-b, --playbackwards create the movie to play backwards
Make a .mp4 movie from the testmovie frames created by stop_action_recorder.py, default two frames per second, and save the resulting movie as finalmovie.mp4:
$ python make_mpeg.py testmovie finalmovie
Make a .mp4 movie from the testmovie frames created by stop_action_recorder.py, default two frames per second, make it play backwards (frames in the opposite order that they were recorded), and save the resulting movie as finalmovie.mp4:
$ python make_mpeg.py testmovie finalmovie -b
Make a .mp4 movie from the testmovie frames created by stop_action_recorder.py, one frame per second, and save the resulting movie as finalmovie.mp4:
$ python make_mpeg.py testmovie finalmovie -f 1
If the number frames per second specified is negative or zero, make_mpeg.py will display a message like the one below and exit:
frames per second must be greater than zero
If make_mpeg.py is unable to open the first frame file, it will display a message like the one below and exit:
input file testmovie.001.png does not exist
$ python delete_frame_set.py -h
usage: delete_frame_set.py [-h] [-x] [-d] target_movie_name
Delete frame set
positional arguments:
target_movie_name name of the stop action movie frame set to delete
optional arguments:
-h, --help show this help message and exit
-x, --deletewithoutconfirmation
delete without asking for confirmation
-d, --debug display debugging messages
Delete all of the files associated with a stop action movie created by stop_action_recorder.py for a movie called testmovie. Note delete_frame_set.py will not delete any files created by make_mpeg. delete_frame_set.py will ask for confirmation to delete the files.
$ python delete_frame_set.py testmovie
Delete all of the files associated with a stop action movie created by stop_action_recorder.py for a movie called testmovie. A command argument is used with delete_frame_set.py to not ask for confirmation to delete the files. Use the '-x' or '--deletewithoutconfirmation' arguments with caution.
$ python delete_frame_set.py testmovie -x
delete_frame_set.py will ask for confirmation to delete the files associated with the movie using a message that looks like this:
delete frame files for testmovie? Type YES to confirm:
If any response other than YES is typed, the files will not be deleted and the message below will be displayed:
files will not be deleted
If YES was typed or the -x or --deletewithoutconfirmation command line arguments were specified, a message like the one below will be displayed after the files have been deleted:
frame set testmovie deleted
If the frame count file for the movie is not found, delete_frame_set.py will display a message like the one below and exit:
can not open target frame count file testmovie
If a frame file associated with the stop action movie can not be found, a message like the one below will be displayed and the execution will be stopped.
testmovie.026.png does not exist
$ python repeat_first_frame.py -h
usage: repeat_first_frame.py [-h] [-r FIRSTFRAMEREPEAT] [-d]
input_movie_name output_movie_name
Create frame set with repeated first frame
positional arguments:
input_movie_name file name of the input stop action movie
output_movie_name file name of the output stop action movie
optional arguments:
-h, --help show this help message and exit
-r FIRSTFRAMEREPEAT, --firstframerepeat FIRSTFRAMEREPEAT
number of times to repeat the first frame on playback
-d, --debug display debugging messages
Create a new version of the stop action testmovie movie called newmovie with the first frame repeated 40 times (at 10 frames per second this would be 4 seconds, at 20 frames per second this we be 2 seconds).
$ python repeat_first_frame.py testmovie newmovie -r 40
If a frame file associated with the stop action movie can not be found, a message like the one below will be displayed and the execution will be stopped.
input frame file testmovie does not exist: processing stopping
If the frame count file for the movie is not found, repeat_first_frame.py will display a message like the one below and exit:
can not open input frame count file testmovie
If the number of times to repeat the first frame is negative or zero, repeat_first_frame.py will display the following message and exit:
first frame repeat must be greater than zero
Each time a frame is copied, a message like the one below will be displayed:
copying testmovie.012.png to newmovie.032.png
After all the new movie is created, a message like the following will be displayed:
new frame set newmovie with first frame repeated 20 times successfully created
$ python repeat_last_frame.py -h
usage: repeat_last_frame.py [-h] [-r LAST_FRAME_REPEAT] [-d]
input_movie_name output_movie_name
Create frame set with the last frame repeated
positional arguments:
input_movie_name file name of the input stop action movie
output_movie_name file name of the output stop action movie
optional arguments:
-h, --help show this help message and exit
-r LAST_FRAME_REPEAT, --lastframerepeat LAST_FRAME_REPEAT
number of times to repeat the last frame
-d, --debug display debugging messages
Create a new version of the stop action testmovie movie called newmovie with the last frame repeated 40 times (at 10 frames per second this would be 4 seconds, at 20 frames per second this we be 2 seconds).
$ python repeat_last_frame.py testmovie newmovie -r 40
If a frame file associated with the stop action movie can not be found, a message like the one below will be displayed and the execution will be stopped.
input frame file testmovie does not exist: processing stopping
If the frame count file for the movie is not found, repeat_last_frame.py will display a message like the one below and exit:
can not open input frame count file testmovie
If the number of times to repeat the first frame is negative or zero, repeat_last_frame.py will display the following message and exit:
last frame repeat must be greater than zero
Each time a frame is copied, a message like the one below will be displayed:
copying testmovie.012.png to newmovie.032.png
After all the new movie is created, a message like the following will be displayed:
new frame set newmovie with last frame repeated 20 times successfully created
Create a 20 frame per second stop action movie called testmovie with the first frame repeated for one second and the last frame repeated for 5 seconds:
Record the movie:
$ python stop-action-recorder.py testmovie
Preview the movie:
$ python stop_action_player.py testmovie -t XXX -a 20 -z 100
Create a new temporary movie with the first frame repeated 20 times:
$ python repeat_first_frame.py testmovie tempmovie1 -r 20
Create a new temporary movie with the last frame repeated 100 times:
$ python repeat_last_frame.py tempmovie1 tempmovie2 -r 100
Create a MP4 file with the movie:
$ python make_mpeg.py tempmovie2 testmovie -f 20
Delete the files associated with the two temporary files:
$ python delete_frame_set.py tempmovie1
$ python delete_frame_set.py tempmovie2
The make_mpeg python program uses FFmpeg to create the mp4 file. Instructions for installing FFmpeg can be found here.
The stop-action-movie-maker python programs requires the the OpenCV for Python library for Python 2 to be installed. Installing OpenCV on MacOS can be tricky, good instructions can be found here.
After installing CV2 for your operating system, change to the directory where you want the stop-action-movie-maker files to be installed.
Install the stop-action-movie-maker files by cloning this repository with this command:
$ git clone https://github.com/makeralchemy/stop-action-movie-maker
Make your first stop action movie with the command:
$ python stop_action_recorder.py testmovie
This project is licensed under the MIT license.