Visualise a latex document git history

mosaic.sh

# Visualise a latex document git history

# loop through commits, create a PDF from your main file for each
# translate the pages of that PDF to a single image
# create GIF/mp4 from the folder of images created

# run within your local repository
# prerequisites: ImageMagick and FFmpeg

# create output folder
mkdir mosaic
# pull latest
git pull
echo "Processing commits..."
# move backwards through the commit history
# change branch name as necessary
for commit in $(git rev-list master)
do
  # hard reset files to that commit 
  git reset --hard $commit
  # assumes main file is 'main.tex' 
  # multiple passes for bib...
  # skip any compilation failures
  pdflatex -interaction=nonstopmode -halt-on-error main.tex
  bibtex main.aux
  pdflatex -interaction=nonstopmode -halt-on-error main.tex 
  pdflatex -interaction=nonstopmode -halt-on-error main.tex
  # lay document out on (constant) suitably sized grid
  # here, 4x3 for max 10 pages
  # output as timestamped pdf to mosaic folder
  montage -geometry 250x250+0+0 -tile 4x3 main.pdf mosaic/out-$(date +"%T").png
done
echo "Creating GIF..."
# create (reverse) GIF from mosaic folder (this can be time consuming; play with flags accordingly)
# modify delay as needed
convert -reverse -delay 3 -loop 0 -limit map 0 mosaic/*.png mosaic.gif
# output as video also, if needed
ffmpeg -i mosaic.gif -movflags faststart -pix_fmt yuv420p -vf "scale=trunc(iw/2)*2:trunc(ih/2)*2" mosaic.mp4

I get this error:
fatal: ambiguous argument 'amia': unknown revision or path not in the working tree.

(Running in git bash on Windows)

(Not an expert in these areas - quite likely that I'm experiencing a basic problem)

Left my default branch name in :) try now

To add, ImageMagick and FFmpeg are prerequisites. Not sure what support for them is like on Windows