Ubuntu – Download videos from youtube playlist or user based on date

You can use the following switch:

 --playlist-items ITEM_SPEC       Playlist video items to download. Specify
                                     indices of the videos in the playlist
                                     separated by commas like: "--playlist-items
                                     1,2,5,8" if you want to download videos
                                     indexed 1, 2, 5, 8 in the playlist. You can
                                     specify range: "--playlist-items
                                     1-3,7,10-13", it will download the videos
                                     at index 1, 2, 3, 7, 10, 11, 12 and 13.

So it would be:

youtube-dl -f 22 --playlist-items 7-X https://www.youtube.com/playlist?list=PLO-hrPk0zuI18xlF_480s6UiaGD7hBqJa

where X is the number of videos in the playlist.

Playlist

youtube-dl -f FORMAT -ciw --output '%(title)s.%(ext)s' --playlist-start NUMBER-START --playlist-end NUMBER-END <url-of-playlist>  

...where <url-of-playlist> is replaced by the URL of the playlist, replace FORMAT with any available video format, for example 18, NUMBER-START is the number of the video in the playlist to start downloading first, and NUMBER-END is the number of the video in the playlist to download last.

Channel

If a channel has more than one playlist, click on the first playlist and download all the videos in the selected playlist using the above command. Then repeat for each playlist in the channel.

Explanation

-f, --format FORMAT
    video format code. The -F option (capital F) displays all available video  
    formats for a video link. Example: youtube-dl -F <url-of-video>

-c, --continue                   
    force resume of partially downloaded files

-i, --ignore-errors              
    continue on download errors, for example to skip unavailable videos  
    in a channel   

-w, --no-overwrites
    do not overwrite files 

Convert all the video titles to lowercase

youtube-dl -f FORMAT -ciw --output '%(title)s.%(ext)s' --playlist-start NUMBER-START --playlist-end NUMBER-END <url-of-playlist>     
find -type f -exec rename 'y/A-Z/a-z/' {} +

Explanation

--output '%(title)s.%(ext)s'  
    output file name(s) as the name of the video, followed by a dot character and the video's extension  

find -type f 
    Find all files.

y/source/destination/  
    Transliterate the characters in the pattern space which appear in source   
    to the corresponding character in destination.