Video Cutting with ffmpeg

ffmpeg_snipplets.txt

# Output every single frame from the video into an image file:
ffmpeg -i "input.mp4" frames/out_%03d.png

ffmpeg -i input.mp4 output.webm


# Trim off fist 2 seconds:
ffmpeg -i input.mkv -ss 2 -vcodec copy -acodec copy output.flv


# Extract fist 10 seconds:
ffmpeg  -i input.mkv -ss 0 -t 10 out.mkv 

# Extract last 10 seconds
ffmpeg -sseof -10 -i input.mp4 output.mp4

# Convert to gif:
ffmpeg -i input.mp4 -r 12 -s 320x180 output.gif


#counting frames:
ffmpeg -i input.mp4 -map 0:v:0 -c copy -f null -y /dev/null 2>&1 | grep -Eo 'frame= *[0-9]+ *' | grep -Eo '[0-9]+' | tail -1
#OR:
ffprobe -v error -select_streams v:0 -show_entries stream=nb_frames -of default=nokey=1:noprint_wrappers=1 input.mp4


#extract frame number 20:
ffmpeg -i input.mp4  -vf "select=gte(n\,20)" -vframes 1 out_img.png

#compress an mp4 file more or less lossless:
ffmpeg -i input.mp4 -vcodec h264 -acodec aac output.mp4

with python script:
```python
from pathlib import Path
import os
suffix = ".mp4"
input_path= Path.home() / "Desktop/foo"
file_paths= [subp for subp in input_path.rglob('*') if  suffix == subp.suffix]
file_paths.sort()

output_path =  Path.home() / "Desktop/foo/final"
output_path.mkdir(parents=True, exist_ok=True)


for file_p in file_paths:
	input = str(file_p)
	output = str(  output_path / file_p.name  ) 
	command = f"ffmpeg -i {input} -vcodec libx265 -crf 28 -acodec aac {output}"
	print(command)
	os.system(command)
```