strip_videos

This contains four scripts that may be used to automate cutting segments out of videos based on timestamps of keywords in transcripts.

Dependencies

For python, we use collections, os, sys, re, itertools, ffmpeg, and pathlib. We also require ffmpeg to be installed an in the PATH environment. After the latest update there is no need for any bash.

Usage

Bookmarking quiz times

The script looks for either 1) occurrences of all the words ["explanation", "slide" and "start(s/ed)"], and one of the words ["poll", "quiz", "question"]; or 2) "quiz start(s/ed)" in a line to mark the start of the expalnation. It also looks for "quiz stop(s/ed)" (subject to change) in the Zoom transcript but this is optional. These can be added in manually after the fact.

Running all scripts at once

Provided a zoom .vtt transcript file and a video,

python3 run.py <transcript.vtt> <video>

or in Bash (may be deprecated soon)

./run.sh <transcript.vtt> <video>

will extract quiz times. It will then run the second script to ask for adjustments. Finally it will cut the segments out and output them to the current directory.

Extract quiz start times from transcript

Provided a Zoom transcript file,

python3 find_quiz_times.py <transcript.vtt>

will output a file called <quiz_times_in_transcript.vtt> in the same directory as the transcript. The filw contains quiz start and end times and will flag any unbalanced start/end times which can be edited in the transcript manually.

Adjust times by a fixed time offset

Provided a file output by find_quiz_times.py with .vtt extension,

python3 offset_times.py <quiz_times_in_transcript.vtt>

will provide an interactive program in the terminal. It lists the start time of the first quiz and allows the user to confirm or specify the new start time in hh:mm:ss. It will prompt for user confirmation and output a file <quiz_times_in_transcriptfile> which contains the new times. It also produces a warning if start times are over 5 minutes long, and provides an option to reduce the maximum video length. It will replace the file.

Cut segments of video

Privided with the <quiz_times_in_transcript.vtt> file,

python3 cut_videos.py <quiz_times_in_transcript.vtt> <video>

or in bash (may be deprecated soon)

./cut_videos.sh <quiz_times_in_transcript.vtt> <video>

will cut the desired segments and output them as quiz_<number>_video. It will output video clips to the same directory that