Cut a video file from frame.io comments.

cut_segments.sh

#!/bin/bash

# Run with:
# bash <(curl -sL "https://gist.githubusercontent.com/krasi-georgiev/1f167a2136bbce5824c6516d2777ef79/raw/cut_segments.sh")

shopt -s nullglob

### Step 1: Select CSV file
csv_files=( *.csv )
if [ ${#csv_files[@]} -eq 0 ]; then
  echo "❌ No CSV files found."
  exit 1
fi

if [ -t 0 ]; then
  echo "Available CSV files:"
  select csv_file in "${csv_files[@]}"; do
    [[ -n "$csv_file" ]] && break
    echo "❌ Invalid selection. Try again."
  done
else
  csv_file="${csv_files[0]}"
  echo "ℹ️  Auto-selected CSV: $csv_file"
fi

### Step 2: Select MP4 file
mp4_files=( *.mp4 )
if [ ${#mp4_files[@]} -eq 0 ]; then
  echo "❌ No MP4 files found."
  exit 1
fi

IFS=$'\n' mp4_files=( $(ls -S *.mp4) )

if [ -t 0 ]; then
  echo "Available MP4 files (sorted by size):"
  select video_file in "${mp4_files[@]}"; do
    [[ -n "$video_file" ]] && break
    echo "❌ Invalid selection. Try again."
  done
else
  video_file="${mp4_files[0]}"
  echo "ℹ️  Auto-selected MP4: $video_file"
fi

### Step 3: Detect FPS
fps_raw=$(ffprobe -v error -select_streams v:0 -show_entries stream=avg_frame_rate \
  -of default=noprint_wrappers=1:nokey=1 "$video_file")

if [[ "$fps_raw" == */* ]]; then
  FPS=$(awk -F'/' '{ if ($2==0) print "0"; else printf "%.6f", $1/$2 }' <<< "$fps_raw")
else
  FPS=$(printf "%.6f" "$fps_raw")
fi

if [[ -z "$FPS" || "$FPS" == "0" || "$FPS" == "nan" || "$FPS" == "-nan" ]]; then
  echo "❌ Could not detect FPS properly from video."
  exit 1
fi

echo "🎞 Detected FPS: $FPS"

# Source framerate for comments
source_fps=30

# Print adjustment warning if needed
if (( $(bc <<< "$FPS != $source_fps") )); then
  echo "⚠️ WARNING: INPUT TIMECODES ARE BASED ON 30FPS. ADJUSTING FRAMES TO TARGET ${FPS} FPS..." >&2
fi

### Step 4: Parse Timecodes (column 16)
echo "📋 Parsing Timecode (column 16)..."
mapfile -t timecodes < <(
  tail -n +2 "$csv_file" | awk -F',' '
    {
      gsub(/^"|"$/, "", $16)
      if ($16 != "") print $16
    }
  '
)

if (( ${#timecodes[@]} < 2 )); then
  echo "❌ Not enough timecode entries found."
  exit 1
fi

echo "🎬 Preparing $(( ${#timecodes[@]} / 2 )) cuts from ${#timecodes[@]} timecodes..."

### Create cuts folder
cuts_folder="cuts"
mkdir -p "$cuts_folder"

### Helper: Convert Timecode to seconds with frame adjustment
function timecode_to_seconds() {
  local tc="$1"
  local fps="$2"
  local source_fps=30

  IFS=':' read -r hh mm ss ff <<< "$tc"

  if (( $(bc <<< "$fps != $source_fps") )); then
    adjusted_ff=$(bc <<< "scale=6; $ff * ($fps / $source_fps)")
    overflow_sec=$(bc <<< "scale=6; $adjusted_ff / $fps")
    ff=$(printf "%.0f" $(bc <<< "$adjusted_ff % $fps"))
    ss=$(bc <<< "$ss + $overflow_sec")
  fi

  total=$(bc <<< "$hh*3600 + $mm*60 + $ss + $ff/$fps")
  echo "$total"
}

### Helper: Format Timecode to hms for filenames
function format_timecode_for_filename() {
  local tc="$1"
  IFS=':' read -r hh mm ss ff <<< "$tc"
  printf "%02dh%02dm%02ds" "$((10#$hh))" "$((10#$mm))" "$((10#$ss))"
}

### Step 5: Cut segments
for (( i=0; i<${#timecodes[@]}-1; i+=2 )); do
  start_tc="${timecodes[$i]}"
  end_tc="${timecodes[$((i+1))]}"

  start_sec=$(timecode_to_seconds "$start_tc" "$FPS")
  end_sec=$(timecode_to_seconds "$end_tc" "$FPS")

  [[ "$start_sec" == .* ]] && start_sec="0$start_sec"
  [[ "$end_sec" == .* ]] && end_sec="0$end_sec"

  duration=$(bc <<< "scale=6; $end_sec - $start_sec")
  [[ "$duration" == .* ]] && duration="0$duration"

  # Format filename using Hours-Minutes-Seconds
  safe_start_tc=$(format_timecode_for_filename "$start_tc")
  safe_end_tc=$(format_timecode_for_filename "$end_tc")

  output_file="${cuts_folder}/segment_${safe_start_tc}_to_${safe_end_tc}.mp4"

  echo "⏱ Cutting: $start_tc ($start_sec s) → $end_tc ($end_sec s) duration: $duration s"

  ffmpeg -hide_banner -loglevel error -y \
    -ss "$start_sec" -i "$video_file" -t "$duration" \
    -c copy -avoid_negative_ts 1 "$output_file"

  if [ $? -eq 0 ]; then
    echo "✅ Created: $output_file"
  else
    echo "❌ Failed: $output_file"
  fi
done

echo "🏁 All cuts completed! Files saved inside /cuts folder."