Extract YouTube thumbnail images of standard and max resolutions

yt_grabber.sh

#!/bin/bash

#####################################
# File: yt_grabber.sh
# Description: Extract YouTube thumbnail images of multiple resolutions
# Created: Monday, 17th May 2021 
# Author: Anjum Rashid 
# -----
# Last Modified: Tuesday, 18th May 2021 
# -----
#####################################

protocol="https://"
api_endpoint="i.ytimg.com/vi"
default_url="https://youtu.be/FwRIMBMJj2s"

function YTthumbnailSearch(){

	echo "Press '1' for a demo, '2' to enter your own URL : "
	read choice

	if  [ "$choice" = '1' ] 
	then 

	  echo "Going with default URL"

	  declare ARR=($(echo $default_url | tr "/" "\n"))
	  echo "Captured Video ID : ${ARR[2]}"

	  video_id=${ARR[2]}
	  
	  # max resolution
	  thumbnail_maxres_url="https://${api_endpoint}/${video_id}/maxresdefault.jpg"
	  echo "Connecting to ${thumbnail_maxres_url}"

	  # standard resolution
	  thumbnail_standard_url="https://${api_endpoint}/${video_id}/sddefault.jpg"
	  echo "Connecting to ${thumbnail_standard_url}"
	  
	  # make lowercase
	  lower_video_id=$(echo "$video_id" | tr '[:upper:]' '[:lower:]')
	  directory_path="downloads/$lower_video_id"

	  # check if directory exists
	  if [ -d $directory_path ]
	  then
	  	echo "Directory "$lower_video_id" already exists." 
	  else
	  	echo "Downloading to "${lower_video_id}" directory"
	  	mkdir $directory_path
	  fi

	  maxres_status_code=$(curl -s -I "${thumbnail_maxres_url}" | head -1 | awk {'print $2'})
	  sdres_status_code=$(curl -s -I "${thumbnail_standard_url}" | head -1 | awk {'print $2'})
	  
	  	# if encounters with 40X serie error 
	  	if [ $maxres_status_code -ne '404' ]
		then
			echo "Downloading max resolution"
			curl -s $thumbnail_maxres_url > $directory_path/maxres.jpg
		else
			echo "Thumbnail max resolution not available!"
		fi
		if [ $sdres_status_code -ne '404' ]
		then
			echo "Downloading standard resolution"
		  	curl -s $thumbnail_standard_url > $directory_path/sd.jpg
		else
			echo "Thumbnail standard resolution not available!"
	  	fi

	  	echo "Download complete! Check "${directory_path}" folder for the images!"

	elif [ "$choice" = '2' ] 
    then

	  echo "Collect YouTube share link and paste here:"
	  read link
	  
	  declare ARR=($(echo $link | tr "/" "\n"))
	  echo "Captured Video ID : ${ARR[2]}"

	  video_id=${ARR[2]}
	  
	  thumbnail_maxres_url="https://${api_endpoint}/${video_id}/maxresdefault.jpg"
	  echo "Connecting to ${thumbnail_maxres_url}"

	  thumbnail_standard_url="https://${api_endpoint}/${video_id}/sddefault.jpg"
	  echo "Connecting to ${thumbnail_standard_url}"
	  
	  lower_video_id=$(echo "$video_id" | tr '[:upper:]' '[:lower:]')
	  directory_path="downloads/$lower_video_id"

	  if [ -d $directory_path ]
	  then
	  	echo "Directory "$lower_video_id" already exists." 
	  else
	  	echo "Downloading to "${lower_video_id}" directory"
	  	mkdir $directory_path
	  fi

	  maxres_status_code=$(curl -s -I "${thumbnail_maxres_url}" | head -1 | awk {'print $2'})
	  sdres_status_code=$(curl -s -I "${thumbnail_standard_url}" | head -1 | awk {'print $2'})
	  
	  	# if encounters with 40X serie error 
	  	if [ $maxres_status_code -ne '404' ]
		then
			echo "Downloading max resolution"
			curl -s $thumbnail_maxres_url > $directory_path/maxres.jpg
		else
			echo "Thumbnail max resolution not available!"
		fi
		if [ $sdres_status_code -ne '404' ]
		then
			echo "Downloading standard resolution"
		  	curl -s $thumbnail_standard_url > $directory_path/sd.jpg
		else
			echo "Thumbnail standard resolution not available!"
	  	fi

	  	echo "Download complete! Check "${directory_path}" folder for the images!"
	else 
	  echo "Wrong choice"
	fi 
}


YTthumbnailSearch