Dashcam ffmpeg timelapse script

run.sh

#!/bin/bash

# Extracts frames every 3 seconds from dash cam videos and creates a timelapse
# Save this file, chmod +x ./run.sh, and then run with ./run.sh

# Configuration
INPUT_DIR="./raw_video"  # Change this to your video files directory
OUTPUT_DIR="./timelapse_frames"
FINAL_VIDEO="dashcam_timelapse.mp4"
FRAME_RATE=60
RESOLUTION="1280x720"

# Create output directory for frames
mkdir -p "$OUTPUT_DIR"

echo "Starting dash cam timelapse creation..."
echo "Input directory: $INPUT_DIR"
echo "Frame extraction rate: 1 frame every 3 seconds"
echo "Final video frame rate: ${FRAME_RATE}fps"

# Counter for sequential frame numbering
frame_counter=1

# Find and sort all MP4 files
echo "Finding MP4 files..."
mp4_files=($(find "$INPUT_DIR" -name "*.mp4" -type f | sort))

if [ ${#mp4_files[@]} -eq 0 ]; then
    echo "Error: No MP4 files found in $INPUT_DIR"
    exit 1
fi

echo "Found ${#mp4_files[@]} MP4 files"

# Extract frames from each video
for video_file in "${mp4_files[@]}"; do
    echo "Processing: $(basename "$video_file")"
    
    # Extract frames every 3 seconds
    # -vf fps=1/3 means 1 frame every 3 seconds
    # %08d ensures proper ordering with zero-padding
    ffmpeg -i "$video_file" \
           -vf "fps=1/3,scale=$RESOLUTION:flags=lanczos" \
           -pix_fmt rgb24 \
           -compression_level 9 \
           -q:v 8 \
           "$OUTPUT_DIR/frame_$(printf "%08d" $frame_counter)_%03d.png" \
           -y -loglevel warning
    
    # Count how many frames were extracted from this video
    extracted_frames=$(ls "$OUTPUT_DIR"/frame_$(printf "%08d" $frame_counter)_*.png 2>/dev/null | wc -l)
    
    if [ $extracted_frames -gt 0 ]; then
        echo "  Extracted $extracted_frames frames"
        # Update counter for next video (each 3-min video at 1 frame per 3 sec = ~60 frames)
        frame_counter=$((frame_counter + 100))  # Leave gap for proper sorting
    else
        echo "  Warning: No frames extracted from this video"
    fi
done

# Create final timelapse video
echo "Creating final timelapse video..."
ffmpeg -framerate $FRAME_RATE \
       -pattern_type glob \
       -i "$OUTPUT_DIR/*.png" \
       -c:v libx264 \
       -pix_fmt yuv420p \
       -crf 18 \
       -preset medium \
       "$FINAL_VIDEO" \
       -y

if [ $? -eq 0 ]; then
    echo "Success! Timelapse created: $FINAL_VIDEO"
    echo "Video stats:"
    echo "  - Duration: ${duration} seconds"
    echo "  - Frame rate: ${FRAME_RATE}fps"
    echo "  - Resolution: $RESOLUTION"
    
    # Ask if user wants to keep frame files
    echo ""
    read -p "Delete extracted frame files? (y/N): " -n 1 -r
    echo
    if [[ $REPLY =~ ^[Yy]$ ]]; then
        rm -rf "$OUTPUT_DIR"
        echo "Frame files deleted."
    else
        echo "Frame files kept in: $OUTPUT_DIR"
    fi
else
    echo "Error: Failed to create final video"
    exit 1
fi

echo "Done!"