Video Player

This app is a video player for NumWorks calculators. It allows you to play any videos that have been converted to a compatible format.

Download

Official releases are available on GitHub Releases.

If you prefer, you can use this direct link:

VideoPlayer 1.1.1

How to get videos

You can take sample video from samples folder on the github repository. Or convert your own videos following the instructions below.

To convert a video, you can use the ffmpeg command line tool. Here is an example command assuming that your video is called input.mp4 in the current directory:

Keep the resolution at 320×240. Adjust -q:v, fps= and -t for quality, fps and duration.

With cropping:

ffmpeg -i input.mp4 \
  -vf "scale=320:240:force_original_aspect_ratio=increase,crop=320:240,setsar=1:1,fps=15" \ # Cropping to 320x240
  -t 00:00:30 \ # Limit to 30 seconds
  -vcodec mjpeg \ # Use the MJPEG codec
  -q:v 24 -an \ # Quality and no audio
  output.mjpeg

Without cropping:

ffmpeg -i input.mp4 \
  -vf "scale=320:240:force_original_aspect_ratio=increase,setsar=1:1,fps=15" \ # Scaling to 320x240
  -t 00:00:30 \ # Limit to 30 seconds
  -vcodec mjpeg \ # Use the MJPEG codec
  -q:v 24 -an \ # Quality and no audio
  output.mjpeg

This command will convert your input.mp4 file into a output.mjpeg one.

A video at 320x240 15fps t30 q24 is around 1.2MB.

How to use the app

Key	Action
Back	Quit app
Shift	Change FPS
EXE	Debug mode

If you change fps, they are saved in the calculator storage for next time.

It runs around ~35 fps on n0120, and around ~15 fps on n0110 and n0115

Installation

To install the Video Player app, follow the instructions in the how to install guide to install it along with the mjpeg file.

Why not use Playa ?

Playa is not open source while VideoPlayer is.
Playa bin weigh 249KB while VideoPlayer weighs only 27KB.
VideoPlayer offers more features like changing target fps on the fly to match with the converted video, and a debug mode to check performance. Preferences are saved on the calculator storage.
The video conversion for VideoPlayer is more flexible since you can choose target fps on the calculator, so the video is not sped up to the calculator limit. And thus it leaves storage to change other parameters.

Source code

Source code for VideoPlayer is available here.