'Some folks' use youtube-dl on a regular basis, to pull raw video and create new content. Early in 2023 it appeared to stop working.
$ youtube-dl https://www.youtube.com/watch?v=8QWjCzULyNA [youtube] 8QWjCzULyNA: Downloading webpage ERROR: Unable to extract uploader id; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see https://yt-dl.org/update on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
Forums seemed to imply the issue was known and a fix was in play, so I put my feet up and figured I'd check back in a few weeks. A month, or two, goes by and reinstallation/retrying didn't seem to resolve. So I revisited the fix posts and found it referenced a different package/utility so I tried that out.
You may notice, a number of my posts make use of the youtube-dl utility. Specifically, I used this to download source videos to show FFMpeg video conversion.
I normally install youtube-dl via the Ubuntu package manager:
$ sudo apt-get install youtube-dl
But, this version is typically 'well seasoned', read that as old.
Alternatively, since the utility is authored in Python, you can install it via Python PIP:
$ sudo pip install youtube-dl
The PIP version is often a bit dated as well, so occasionally it doesn't work with YouTube.
An alternative means is to install the latest version, directly from http://yt-dl.org/update
I began with an overall objective of being able to:
1) get a list of the top 100 songs for a given year from the Billboard Charts
2) perform a search for each song on YouTube using the title and artist
3) download the song
4) overlay the title/artist on the video
5) finally, create a video collage consisting of a 30 sec video clip for each song
Let's walk through the steps. Let's focus on the year 1994 to pay tribute to the high school graduation year of my good friend Marshall, likely the only reader of this blog. That shows true dedication 'Old Fashioned', poor judgement in good use of your time, but true dedication.
I first took the path of parsing the HTML and extracting the music list into a series of strings but I later abandoned that effort by dusting off an old tool that I last used back in college, say 1996-1998'ish. Lynx is a text-based web browser with a sexy little secret, the ability to dump to a text file, making parsing the contents significantly easier.
This command will perform a Youtube search and prioritize videos of MP4 format. The output specifies a prefix, there is not guarantee as to the format. While there are pages of documentation on Youtube-dl we won't get into detail here, know however you can tailor your search to limit format, quality, resolution. frame-rate,.... Given we aren't constraining such video qualities we'll enforce some constraints post-processing the videos after we've downloaded them. We can ensure a H264 format within an MP4 container by examining what was downloaded and reencode it if necessary;
This is a good stage to generate a PNG image to overlay that consists of the List #, Artist and Title:
$ convert -background white -fill black -font FreeSerif-Italic -pointsize 46 label:"1 - Ace of Base - The Sign" 001.png
Step 4 -- Overlay the Title/Artist on the Video
Ensuring the videos share consist resolution and frame-rate will make our lives much easier. For instance, the the font size of overlay PNG is aimed at 720p videos. When we later concatenate the videos into a single video you'll find the input videos need to share a consistent frame-rate or the audio falls out of sync and video can stall out. Let's transcode the Youtube video, normalize it to 720p, 30fps and let's seek in 60 seconds and grab a 30 sec clip.
For the observant reader, you may notice the overlay position of (H-56), this places the PNG image at x,y location 0,720-56. For purposes of understanding, I provided the height dimension of the PNG image which places the overlay where we want it.
Step 5 -- Concatenate the Videos
The last step was the one that gave me the most trouble and made me miss my self-enforced blog deadline last week. Concatenating the videos occasionally resulted in stalled video or Kung Fu Theatre style audio out-of-sync issues. Despite many a Google search, I finally found through extensive debugging that the cause of the problem was supplying input videos that didn't have a consistent frame-rate so take care to enforce that before attempting this step like we did in the previous step.
Concating the videos is pretty straightforward: 1) provide a list of video files in a text file and 2) issue a concat filter via FFMpeg.
$ cat files.txt
file 'clip-001.mp4'
file 'clip-002.mp4'
file 'clip-003.mp4'
file 'clip-004.mp4'
The text file (e.g. files.txt) needs to be located in the same working directory where you issue the FFMpeg command.
