Convert PDF into a GIF; https://github.com/insertish/dotfiles/blob/main/.config/fish/functions/convert-pdf-to-gif.fish

convert.fish

#!/bin/fish
# convert the PDF into a sequence of images
# pick input filename
set PDF_NAME abc.pdf
# you may need to experiment with density to find the correct resolution
set DENSITY 300

convert -density $DENSITY -quality 100 $PDF_NAME seq.png

# convert the sequence of images into a GIF
# rate is in hz (i.e. 0.5/s = 1 every 2s)
set RATE 0.5
# pick the start slide (minus 1)
set START_SLIDE 8
# number of slides to include
set NUM_SLIDES 13

ffmpeg -f image2 -start_number $START_SLIDE -r $RATE -lavfi palettegen=stats_mode=single[pal],[0:v][pal]paletteuse=new=1 -i seq-%d.png  -frames:v $NUM_SLIDES out.gif

convert.sh

#!/bin/bash
# convert the PDF into a sequence of images
# pick input filename
PDF_NAME=abc.pdf
# you may need to experiment with density to find the correct resolution
DENSITY=300

convert -density $DENSITY -quality 100 $PDF_NAME seq.png

# convert the sequence of images into a GIF
# rate is in hz (i.e. 0.5/s = 1 every 2s)
RATE=0.5
# pick the start slide (minus 1)
START_SLIDE=8
# number of slides to include
NUM_SLIDES=13

ffmpeg -f image2 -start_number $START_SLIDE -r $RATE -lavfi palettegen=stats_mode=single[pal],[0:v][pal]paletteuse=new=1 -i seq-%d.png  -frames:v $NUM_SLIDES out.gif