Camera Capture

Capture snapshots and clips from IP cameras (RTSP/ONVIF) and webcams.

Prerequisites

Install ffmpeg (required):

brew install ffmpeg

For ONVIF device discovery:

pip install onvif-zeep
# or: brew install gst-plugins-bad  (includes ONVIF support)

Camera stream URLs are typically in these formats:

• RTSP: rtsp://user:pass@192.168.1.x:554/stream
• HTTP MJPEG: http://192.168.1.x:8080/video
• Local webcam (macOS): /dev/video0 or device index 0

Commands

Snapshot — single frame to image

# From RTSP stream
ffmpeg -y -rtsp_transport tcp -i "rtsp://user:pass@IP:554/stream1" \
  -vframes 1 -q:v 2 snapshot.jpg 2>/dev/null

# From HTTP MJPEG
ffmpeg -y -i "http://IP:8080/video" -vframes 1 snapshot.jpg 2>/dev/null

# From local webcam (macOS AVFoundation)
ffmpeg -y -f avfoundation -i "0" -vframes 1 webcam.jpg 2>/dev/null

Clip — short video segment

# 10-second clip from RTSP
ffmpeg -y -rtsp_transport tcp -i "rtsp://user:pass@IP:554/stream1" \
  -t 10 -c copy clip.mp4 2>/dev/null

# 5-second clip from webcam
ffmpeg -y -f avfoundation -i "0" -t 5 webcam_clip.mp4 2>/dev/null

List Available Webcams (macOS)

ffmpeg -f avfoundation -list_devices true -i "" 2>&1 | grep -E "^\[AVFoundation"

Thumbnail from saved video

ffmpeg -y -i input.mp4 -ss 00:00:02 -vframes 1 thumbnail.jpg 2>/dev/null

Usage Examples

"Snapshot from front door camera at 192.168.1.10"

ffmpeg -y -rtsp_transport tcp -i "rtsp://admin:admin@192.168.1.10:554/stream1" \
  -vframes 1 -q:v 2 ~/Pictures/front_door_$(date +%Y%m%d_%H%M%S).jpg 2>/dev/null
echo "Saved to ~/Pictures/"

"Take a photo from my webcam"

ffmpeg -y -f avfoundation -i "0" -vframes 1 ~/Pictures/webcam_$(date +%Y%m%d_%H%M%S).jpg 2>/dev/null

"Record 15 seconds from backyard camera"

ffmpeg -y -rtsp_transport tcp -i "rtsp://user:pass@192.168.1.20:554/stream" \
  -t 15 -c copy ~/Movies/backyard_$(date +%Y%m%d_%H%M%S).mp4 2>/dev/null

Rules

• Check if ffmpeg is installed first: which ffmpeg
• If not installed, show brew install ffmpeg and stop
• Always use -y flag to overwrite without prompting
• Suppress verbose ffmpeg output with 2>/dev/null — only show the result path
• Default output directory: ~/Pictures/ for snapshots, ~/Movies/ for clips
• Auto-append timestamp to filenames to avoid collisions
• If RTSP connection times out, suggest using -rtsp_transport tcp (already included above)
• If user doesn't provide camera URL, ask for it or list available webcams
• Never log camera credentials in output or memory