# play a 1000 Hz test sound
ffplay -f lavfi -i "sine=frequency=1000"

# play Mandelbrot without creating the file
ffplay -f lavfi -i mandelbrot

# visualise each single bit of two seconds of Mandelbrot
# (this works on Linux and macOS, untested on Windows)
ffmpeg -f lavfi -i mandelbrot -t 2 -pix_fmt yuv420p -f h264 - | xxd -b -c 1 | grep -o '[01]\{8\}' | echo $(tr -d '\n')

# show histogram of Dufay
ffmpeg -f image2 -i DUFAY_TIFF/Dufay_%06d.tif -c:v rawvideo -pix_fmt uyvy422 -f nut - | ffplay - -vf "histogram=display_mode=overlay" -x 640 -y 480

# generate the SMPTE bars for HD
ffmpeg -f lavfi -i "smptehdbars=1920x1080" -f lavfi -i "sine=frequency=1000" -t 30 SMPTE_HD.mkv

# generate image and sound for test DCP
ffmpeg -f lavfi -i "smptehdbars=1920x1080" -filter:v "hue=H=0.2*t" -c:v rawvideo -t 30 playing_with_the_hue.mkv
ffmpeg -f lavfi -i "anoisesrc=colour=brown" -filter:a "tremolo=f=0.1:d=0.9" -c:a pcm_s24le -ar 96k -t 30 seashore.wav

# low-pass filter
ffplay -af "lowpass=f=3200" seashore_bad.wav

# high-pass filter
ffplay -af "highpass=f=3200" seashore_bad.wav

# sound noise reduction
ffmpeg -i seashore_bad.wav -filter:a "afftdn=nr=10:nf=-25:tn=1" -c:a pcm_s24le seashore_bad_denoised.wav

# adjust audio volume
ffplay -af "volume=volume=10dB" seashore_good.wav
ffmpeg -i seashore_good.wav -filter:a "volume=volume=10dB" seashore_good_louder.wav
ffplay -af "volume=volume=-10dB" seashore_good.wav
ffmpeg -i seashore_good.wav -filter:a "volume=volume=-10dB" seashore_good_quieter.wav

# lossless record in SD (macOS)
ffmpeg -video_size 640x480 -framerate 25 -f avfoundation -i "0:0" -c:v libx264rgb -crf 0 -preset ultrafast -color_range 2 -c:a pcm_s24le -ar 96k -ac 2 output_archive.mkv

# re-encode lossy with subtitles in SRT format
ffmpeg -i output_archive.mkv -c:v libx264 -crf 18 -preset veryslow -pix_fmt yuv420p -filter:v "subtitles=subtitles_file.srt" -c:a aac -ar 48k -movflags +faststart output_streaming.mp4