## Use ffmpeg to stream video from a dahua 4300s to a file or files
You can use ffmpeg to directly pull frames off of a dahua 4300s at full resolution. May be a good
alternative to pricey dvrs which likely cannot record at full resolution, may not work with
the camera, or are prohibitevly expensive

### Simple Stream to file
Simple stream to file. Full resolution

    ffmpeg -loglevel debug -rtsp_transport tcp -i "rtsp://admin:admin@198.175.207.61:554/live" \
    -c copy -map 0 foo.mp4

### Break streamed file into  time segments
ffmpeg can save file in arbitrary segments at fixed intervals. In this example, we save a new file at
10 second intervals, but the value for `segment_time` can be any positive integer

    ffmpeg  -rtsp_transport tcp -i "rtsp://admin:admin@198.175.207.61:554/live"  \
    -f segment -segment_time 10 -segment_format mp4 -reset_timestamps 1 \
    -c copy -map 0 test%d.mp4

### Timestamped output
Output files can be timestamped as well.

    ffmpeg  -rtsp_transport tcp -i "rtsp://admin:admin@198.175.207.135:554/live" \
    -f segment -segment_time 10 -segment_format mp4  -reset_timestamps 1 \
    -strftime 1 -c copy -map 0 -strftime 1 "output-%Y%m%d-%H%M%S.mp4"

### Select stream to read from.
A different url is used to select the substream. Set `subtype` to 0 for main hi-res stream, or
1 for low res substream. Channel looks to always be set to 1

    ffmpeg  -rtsp_transport tcp -i "rtsp://admin:admin@198.175.207.135:554/cam/realmonitor?channel=1&subtype=1" \
    -f segment -segment_time 10 -segment_format mp4  -reset_timestamps 1 \
    -strftime 1 -c copy -map 0 test-%Y%m%d-%H%M%S.mp4