SpaceX

Extraction and analysis of telemetry from SpaceX webcasts. Run this program using Python 3 (I tested it on Python 3.5.1 32bit version). You'll need OpenCV, NumPy, Livestreamer, Streamlink and FFMpeg

extract.py

extract.py is a Python module that allows anyone with a little knowledge of OpenCV to be able to analyse data from SpaceX webcast, Live, after launch or Offline.

Installing the required modules

All of these modules are can be installed using pip in the following manner:

pip install numpy
pip install opencv-python
pip install livestreamer
pip install streamlink

You will need FFMpeg to be installed and be in PATH

Currently, the extract module cannot be installed with any tool (To my very limited knowledge). To get the module, download extract.py and the Templates directory from this repo. In the future I plan to make it pip installable.

Importing the module

Put the extract.py and the Templates folder in the same directpory as your script. To import it to your script, add this line:

import extract.py

Documentation

The module contains quite a lot of functions, but only a few were made for the user. Here is details about the useful function for the user from help(extract).

calc_altitude(frame)
  Get the altitude in the frame.
  :param frame: Frame from the launch.
  :return: The altitude in the frame.

calc_time(frame)
  Get the time in the frame.
  param frame: Frame from the launch.
  return: The time in the frame.

calc_velocity(frame)
  Get the velocity in the frame.
  :param frame: Frame from the launch.
  :return: The velocity in the frame.
        
skip_to_launch(cap) 
  Move cap to the first frame at T+00:00:00
  :param cap: An OpenCV capture of the launch.
  :return: the index of first frame at T+00:00:00
  
skip_from_launch(cap, time)
  Move the capture to T+time (time can be negative) and returns the frame index.
  :param cap: OpenCV capture
  :param time: delta time from launch to skip to
  :return: index of requested frame
  
extract_telemetry(frame)
  Get time, velocity and alitutde values in frame
  :param frame: Frame from the launch.
  :return: tuple of time, velocity and alitutde (In this order)
  
#### WARNING For res='1080p' the function takes between 10 seconds to 5 minutes. In addition to that it might fail (Return a None)
or raise an exception, if it does, try to run it again ####
get_capture(youtube_url, res)
  Get an OpenCV capture of a YouTube video.
  :param youtube_url: A url of the video
  :param res: The resolution of the video.
  :return: An OpenCV capture of the video.

Example of use

This is a script that outputs the time, velocity and altitude values of the Inmarsat 5 F4 launch

import extract
import cv2

cap = extract.get_capture('https://www.youtube.com/watch?v=ynMYE64IEKs', '1080p')

if cap is None:
    exit(1)

extract.skip_to_launch(cap)

while cap.isOpened():
    _, frame = cap.read()

    time, velocity, altitude = extract.extract_telemetry(frame)

    if time is not None:
        print(time, velocity, altitude)

I Highly recommend using 1080p, 720p is supported but is pretty dull. From my tests, 1080p is correct 98% of the time while 720p is less than 60%
The final Python package might not be compadible with older versions of this module

Plans for the future

Make the module a Python package
Better names and documentation (New names for functions, variables, tables and more). I'm open for suggestions.
Better support for 720p video
Moving some settings to a configuration files instread of being hard coded
(Maybe?) Support for other space streams (for example Blue Origin's)

Feedback is very welcome

get_telemetry.py (Old)

-New version will be uploaded soon

Example of use:

python get_telemetry.py -c "JCSAT-14 Hosted Webcast.mp4" -d "JCSAT-14.json" -T 1250 -r false

skaersoe / SpaceX