Scraping and downloading M4S Segmented Audio & Video Files

My school refers students to watch lectures on this short course platform. To access them, certain credentials have to be entered. Videos are embedded as GoolPlayer, with Flowplayer.js script used and they don't give the option to download the videos.

This is a link to the video (need to copy and paste it, clicking it won't work):
https://www.gool.co.il/%D7%94%D7%A0%D7%93%D7%A1%D7%90%D7%99%D7%9D-%D7%AA%D7%9C-%D7%90%D7%91%D7%99%D7%91/%D7%94%D7%A0%D7%93%D7%A1%D7%90%D7%99-%D7%90%D7%93%D7%A8%D7%99%D7%9B%D7%9C%D7%95%D7%AA-%D7%95%D7%A2%D7%99%D7%A6%D7%95%D7%91-%D7%A4%D7%A0%D7%99%D7%9D/%D7%A1%D7%98%D7%98%D7%99%D7%A7%D7%94-~~%D7%A1%D7%95%D7%92%D7%A8%D7%99%D7%99%D7%9D2~~%D7%9E%D7%9B%D7%A0%D7%99%D7%A7%D7%94-%D7%94%D7%A0%D7%93%D7%A1%D7%99%D7%AA~~%D7%A1%D7%95%D7%92%D7%A8%D7%99%D7%99%D7%9D1~~/%D7%9E%D7%91%D7%95%D7%90-%D7%9C%D7%A1%D7%98%D7%98%D7%99%D7%A7%D7%94-(%D7%9E%D7%9B%D7%A0%D7%99%D7%A7%D7%94-%D7%94%D7%A0%D7%93%D7%A1%D7%99%D7%AA)#77794

Observing the network in Chrome, you can find chunks of the video and audio split into segnments, with request url as such:

https://5a153f939af4b.streamlock.net/academy/77794/chunk_ctvideo_ridp0va0br68335_cinit_w270836820_pd60000_qdElEPTQzMjY4OSZ2aWRlb1ZpZXc9MSZhY2Nlc3NUb2tlbj0wOTc1ZWRkOTU4NDc0MzAyYmQ0MjAxN2JhODFhZTY0Ng==_mpd.m4s

I have tried quite a few chrome and firefox extensions to try and download the videos without any luck. Also tried a few M4S scripts on github.

The best thing I found that did do that trick was InviDownloader, an opensource program, BUT, can't seem to grab all segments because of the files name, it changes in a random order, so the program can only grab the first and last one.

Any thoughts or ideas on how can the video be downloaded?

1. To download videos from gool you want to get the mpd file that is transferred to you when you first load the video. That file is responsible for generating the links to the m4s files that you see while loading more of the video.

2. After obtaining the file, you'll want to manually edit it and add the base url that was used to get the mpd file to each of the links inside the mpd file.

for example this link

chunk_ctvideo_rid$RepresentationID$_cs$Time$_w113767869_pd60000_qdElEPTU4NTcmdmlkZW9WaWV3PTEmYWNjZXNzVG9rZW49N2VhMzg5ZjRhNzJmNGFiMWE2NWU2NTI3Y2RjNTdhZTE=_mpd.m4s

will become

https://5a153f939af4b.streamlock.net/bagrut/36808/chunk_ctvideo_rid$RepresentationID$_cs$Time$_w113767869_pd60000_qdElEPTU4NTcmdmlkZW9WaWV3PTEmYWNjZXNzVG9rZW49N2VhMzg5ZjRhNzJmNGFiMWE2NWU2NTI3Y2RjNTdhZTE=_mpd.m4s

3. Now you have a valid mpd file.

To play it you can use vlc.
For example: vlc manifest.mpd

To encode the mpd file to a video file, you can use either cvlc or ffmpeg (note, ffmpeg needs to compiled with some features that might not be enabled in prebuilts. [ffmpeg-full from nixpkgs works for me])

examples:

• cvlc manifest.mpd --sout '#transcode{vcodec=h264,acodec=mp3}:std{access=file,mux=mp4,dst=output.mp4}' --play-and-exit
• ffmpeg -i manifest.mpd -c copy output.mp4

you can detect mpd link by Stream Detector https://addons.mozilla.org/en-US/firefox/addon/hls-stream-detector/ and then download video with youtube-dl Read more about it there https://forum.videohelp.com/threads/388942-How-do-I-download-m4s-segment-videos-and-combine-them-to-mp4-format