Video Recorder Class

Notice: This class_template is now included in the AMMR.

Just add the following to the top of your model:

 #include "<ANYBODY_PATH_MODELUTILS>/Video/CameraClassTemplate.any"

This repository is still usefull as an example on how to use the class template.

This anyscript class_template will allow you to easily create videos from your models.

It can be added into any model to produce videos with a single click. It can also create animated Gif files.

The camera can be configured as a fixed camera or as a moving camera to follow the certain parts of the model.

Usage

Here is a quick example for the impatient:

// Include the Camera template class (Somewhere before Main)
#include "Path/to/Video_Camera/CameraClassTemplate.any"

Main = 
{

  VideoLookAtCamera  MyCam (UP_DIRECTION=y, CREATE_GIF=1) = 
  {
       // The point the camera focus on.
       CameraLookAtPoint = Main.MyModel.Femur.Knee.r;  
       
       // The vertical field of view in meters
       CameraFieldOfView  = 1;
       
       // The direction in which the camera is placed. In global 
       // coordinate with respect to the LookAtPoint. 
       // (Can also be a time varying vector)
       CameraDirection  = {1, 1, -1};
       
       // The background color used for the video
       BackgroundColor = {1, 1, 1};
       
       // Determines the speed of the video. Setting it to 
       // nStep/(tEnd-tStart) make the video run in real time. 
       VideoInputFrameRate  = 10;
       
       // The operations which should be included in the video.
       Analysis = {
           AnyOperation &ref = Main.MyStudy.Kinematics;
       };
  };

};

Previewing the camera

The class does not record what what is in the Model View. Instead the camara view is configured programatically. Class members like CameraLookAtPoint, CameraDirection, and CameraFieldOfView define what the camera records. This is usefull since it allows you get consistent videos.

To get a preview of what the camera records, select and run the Preview operation. It will collect a single frame and launch the Windows image viewer.

Once you are satisfied with the camera settings of the class you are ready create a full video.

Creating the video

To create a video simply select and run the Create_Video operation. That will run the model, collect the frames, convert them to a video and finally play the video.

The video will by default be saved together with the main file of the model. This can of course be customized as well.

More examples

Two examples are included here:

1. Fast toy model to play with the settings
2. A full human model with a camera that spins around the subject

Class description:

Syntax:

  VideoLookAtCamera <object name> (UP_DIRECTION = y, <arg>=<value>) = 
  {
    <member name> = <value>;
  }

Template arguments

Argument	Default	Description
UP_DIRECTION	y	The up direction of the camera. Can be x/y/z
CREATE_GIF	0	Set to 1 to always create animated Gif files from the vide.
_OVER_WRITE	1	If the camra is allow to overwrite existing videos. On by default.
_DEBUG	0	Set to 1 to allow debugging the class. This will show the output of ffmpeg.
_CLEAN_UP_IMAGES	1	If images shoud be deleted after the video is created. Set to 0 to keep the image frames.

Expected members:

Member name	Type	Description
CameraLookAtPoint	AnyVec3	The point the camera focus on. This can be fixed point or some moving point on the model.
CameraFieldOfView	AnyFloat	The vertical field of view in meters at the LookAtPoint.
CameraDirection	AnyVec3	The direction which the camera is placed (In global coordinate with respect to the LookAtPoint).

Optional members:

The following class members are optional. They are listed in order of usefulnes.

Member name	Default	Type	Description
BackgroundColor	{1,1,1}	AnyVec3	The background color ({red, green, blue}) used for the video. Defaults to white.
Counter	-	AnyInt	Counter for numbering the saved images. This defaults to the camera class builtin counter.
VideoName	"Cam1"	AnyString	File name of the video that will be created
VideoResolution	{1920, 1080}	AnyIntArray	Resolution of the output video in {Hight,Width}
VideoInputScale	1	AnyFloat	The ratio between video resolution and input images saved from anybody. Default is to save images in same resolution as the output video. It is an advantage to set this to 2 or 4 when making videos with a low resolution
VideoInputFrameRate	30	AnyInt	Determines the speed of the video. Setting it to nStep/(tEnd-tStart) make the video run in real time.
GifResolution	{600, 600}	AnyIntArray	Resolution of the animated Gif file. Note: Setting this will not alter the orginal aspect ratio.
VideoCodec	"libxvid"	AnyString	The video codec ffmepg will use to create the video. Choose "libxvid" for best for compatibility (eg. with PowerPoint) or "libx264" for best performance
VideoBitRate	8000	AnyInt	Video BitRate in KiloByte
VideoStartFrame	0	AnyInt	This is the start frame used when creating Videos. This can be used to for skipping some of the initial frames.
VideoPathFFMPEG	"ffmpeg.exe"	AnyString	The path to the ffmpeg binary. Defaults to the same directory as the template class.
VideoOutputPath	Dependent	AnyString	The directory to save the video in. This defaults to the directory of the current main file if not specified.
CameraDistance	10	AnyFloat	The distance from the camera to the scene. This does NOT determine the ize of scene, since Perspective is off by default. To zoom in/out, use CameraFeildOfView.
CameraUpDirection	Dependent	AnyVec3	The updirection of the camera as a vector. This is set by default by the UP_DIRECTION but can be overwritten.