NHK Video-On-Demand Downloader

Downloads videos from NHK's Video On Demand Service.

Download a built version for Windows: Releases

Requirements

Google Chrome (this code uses chromedp to obtain the "hidden" video ID due to NHK's fancy schmancy Javascript shenanigans. I didn't want to bother reading their 15k+ lines of JS code just to be able to reproduce the request to get the ID.)
FFmpeg (only if you want to convert your video to mkv afterwards) - not yet implemented

Command line arguments

-u "url" - This is how you let the program know which video you want downloaded. Required.
-p "path" - If you don't want this program to save the video next to the executable, use this argument and specify your desired output path. Optional. (not yet implemented)
-c - Use this if you want to convert the downloaded and merged video to MKV. Why MKV? Because I like it best and I don't really think anyone else will use the code anyway. Note: this only copies the video information into a different kind of media container, no actual encoding is done here. Optional. (not yet implemented)
-dm - Use this if you don't want to merge the small TS files into a single big file. No clue why anyone would want this, but hey, it's here. Optional.
-h - Use this to start Chrome in headless mode if you're reeealy bothered by the Chrome window opening for a few seconds at the start. Highly not really very recommended due to the fact that you will have to restart your computer or manually kill the chrome.exe processes if you want to use the program more than once in a row. Don't blame me - this happens because chromedp is broken. Just don't use -h unless you know what you're doing or you're fine with killing Chrome manually after each use. Check the Troubleshooting section if you got in trouble because of this. Optional, obviuosly.
-? - Lists all possible arguments. Optional.

Troubleshooting

If the Chrome window doesn't close, you probably didn't specify a valid video URL. If the video didn't load on the page for some reason, just try refreshing the page in the Chrome window.
If the only output is timeout waiting for initial target after a few seconds of running, run taskkill -f -im chrome.exe in your command prompt and try again (Windows only, I didn't try it on Linux). This probably happened because you used -h as a command line argument.
If converting fails, you probably didn't add FFmpeg to PATH. Do that first.

Disclaimer

I didn't check, so I'm not sure if using this code is allowed by NHK's TOS. Use only if you've checked and you're sure downloading from their website is not disallowed.

I don't guarantee that this code works. On the contrary - I can guarantee that you'll be able to break it with relative ease. This is not meant to be a robust and future-proof solution for downloading from NHK, it's just something I put together some boring Saturday afternoon.

TODO: