chapter

# $Id. Create chapter in mp4 movie

# #Step 1.
# Copy metadata
# This command will copy movie metadata
# Good start, so we no need to make file from scratch

ffmpeg -i input_file -f ffmetadata ffmetadata_file

# #Step 2.
# Edit metadata 
# Following the format
# Note: TIMEBASE unit num/den = 1/1 means in second
#       TIMEBASE 1/1000 means in microsecond
# Example format
# $EXAMPLE BEGIN
#;FFMETADATA1
#title=bike\\shed
#;this is a comment
#artist=FFmpeg troll team
# Example compute length of video
# from datetime import timedelta                                          
# x = '01:32:59.20'                                                       
# h,m,s=map(float, x.split(':'))                                          
# res = timedelta(hours=h,minutes=m,seconds=s).total_seconds() * 1000     

#[CHAPTER]
#TIMEBASE=1/1000
#START=0
##chapter ends at 0:01:00
#END=60000
#title=chapter \#1
#[STREAM]
#title=multi\
#line
# $EXAMPLE END
#
# #Step 3.
# Reinserting edited metadata can be done as

ffmpeg -i input_file -i ffmetadata_file -map_metadata 1 -codec copy output_file