fsalehpour

# create hardsubs for a video from a SRT file using FFMPEG
# https://stackoverflow.com/a/21369850/1887369

ffmpeg -i video.mp4 -vf "subtitles=subs.srt:force_style='Fontname=Times New Roman,Fontsize=24,PrimaryColour=&H0000ff&'" output.mp4

## to take only a section of the video:
ffmpeg -ss 00:02:00 -copyts -i video.mkv -ss 00:02:00 -vf "subtitles=subs.srt:force_style='Fontsize=24,Fontname=Times New Roman'" -to 00:02:30 cut.mp4

# convert the pixel format using the format filter
# https://stackoverflow.com/a/54196619/1887369

fsalehpour

# Reduce the size of a PDF file
# https://askubuntu.com/a/256449/112818
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook -dNOPAUSE -dQUIET -dBATCH -sOutputFile=output_reduced.pdf input.pdf

# Convert a PDF to grayscale colour
# https://superuser.com/a/164857/989263
gs \
 -sOutputFile=output_gray.pdf \
 -sDEVICE=pdfwrite \
 -sColorConversionStrategy=Gray \