Introduction

Moonfire NVR is an open-source security camera network video recorder, started by Scott Lamb <slamb@slamb.org>. It saves H.264-over-RTSP streams from IP cameras to disk into a hybrid format: video frames in a directory on spinning disk, other data in a SQLite3 database on flash. It can construct .mp4 files for arbitrary time ranges on-the-fly. It does not decode, analyze, or re-encode video frames, so it requires little CPU. It handles six 1080p/30fps streams on a Raspberry Pi 2, using less than 10% of the machine's total CPU.

So far, the web interface is basic: just a table with links to one-hour segments of video. Although the backend supports generating .mp4 files for arbitrary time ranges, you have to construct URLs by hand. There's also no support for motion detection, no authentication, and no config UI.

This is version 0.1, the initial release. Until version 1.0, there will be no compatibility guarantees: configuration and storage formats may change from version to version. There is an upgrade procedure but it is not for the faint of heart.

I hope to add features such as salient motion detection. It's way too early to make promises, but it seems possible to build a full-featured hobbyist-oriented multi-camera NVR that requires nothing but a cheap machine with a big hard drive. I welcome help; see Getting help and getting involved below. There are many exciting techniques we could use to make this possible:

• avoiding CPU-intensive H.264 encoding in favor of simply continuing to use the camera's already-encoded video streams. Cheap IP cameras these days provide pre-encoded H.264 streams in both "main" (full-sized) and "sub" (lower resolution, compression quality, and/or frame rate) varieties. The "sub" stream is more suitable for fast computer vision work as well as remote/mobile streaming. Disk space these days is quite cheap (with 3 TB drives costing about $100), so we can afford to keep many camera-months of both streams on disk.
• decoding and analyzing only select "key" video frames (see wikipedia.
• off-loading expensive work to a GPU. Even the Raspberry Pi has a surprisingly powerful GPU.
• using HTTP Live Streaming rather than requiring custom browser plug-ins.
• taking advantage of cameras' built-in motion detection. This is the most obvious way to reduce motion detection CPU. It's a last resort because these cheap cameras' proprietary algorithms are awful compared to those described on changedetection.net. Cameras have high false-positive and false-negative rates, are hard to experiment with (as opposed to rerunning against saved video files), and don't provide any information beyond if motion exceeded the threshold or not.

Downloading

See the github page (in case you're not reading this text there already). You can download the bleeding edge version from the command line via git:

$ git clone https://github.com/scottlamb/moonfire-nvr.git

Building from source

There are no binary packages of Moonfire NVR available yet, so it must be built from source.

Moonfire NVR is written in the Rust Programming Language. In the long term, I expect this will result in a more secure, full-featured, easy-to-install software. In the short term, there will be growing pains. Rust is a new programming language. Moonfire NVR's primary author is new to Rust. And Moonfire NVR is a young project.

You will need the following C libraries installed:

• ffmpeg version 2.x, including libavutil, libavcodec (to inspect H.264 frames), and libavformat (to connect to RTSP servers and write .mp4 files).

  Note ffmpeg 3.x isn't supported yet by the Rust ffmpeg crate; see rust-ffmpeg/issues/64.

  Additionally, ffmpeg library versions older than 55.1.101, along with 55.1.101, along with all versions of the competing project libav, don't not support socket timeouts for RTSP. For reliable reconnections on error, it's strongly recommended to use ffmpeg library versions >= 55.1.101.

• SQLite3.

• ncursesw, the UTF-8 version of the ncurses library.

On Ubuntu 16.04.1 LTS or Raspbian Jessie, the following command will install all non-Rust dependencies:

$ sudo apt-get install \
               build-essential \
               libavcodec-dev \
               libavformat-dev \
               libavutil-dev \
               libncurses5-dev \
               libncursesw5-dev \
               libsqlite3-dev

Next, you need Rust 1.15+ and Cargo. The easiest way to install them is by following the instructions at rustup.rs.

You can continue to follow the build/install instructions below for a manual build and install, or alternatively you can run the prep script called prep.sh.

$ cd moonfire-nvr
$ ./prep.sh

The script will take the following command line options, should you need them:

• -S: Skip updating and installing dependencies through apt-get. This too can be useful on repeated builds.

You can edit variables at the start of the script to influence names and directories, but defaults should suffice in most cases. For details refer to the script itself. We will mention just one option, needed when you follow the suggestion to separate database and samples between flash storage and a hard disk. If you have the hard disk mounted on, lets say /media/nvr, and you want to store the video samples inside a directory named samples there, you would set:

SAMPLES_DIR=/media/nvr/samples

The script will perform all necessary steps to leave you with a fully built, installed moonfire-nvr binary. The only thing you'll have to do manually is add your camera configuration(s) to the database. Alternatively, before running the script, you can create a file named cameras.sql in the same directory as the prep.sh script and it will be automatically included for you. For instructions, you can skip to "Camera configuration and hard disk mounting".

Once prerequisites are installed, Moonfire NVR can be built as follows:

$ cargo test
$ cargo build --release
$ sudo install -m 755 target/release/moonfire-nvr /usr/local/bin

Further configuration

Moonfire NVR should be run under a dedicated user. It keeps two kinds of state:

• a SQLite database, typically <1 GiB. It should be stored on flash if available.
• the "sample file directory", which holds the actual samples/frames of H.264 video. This should be quite large and typically is stored on a hard drive.

(See guide/schema.md for more information.)

Both kinds of state are intended to be accessed only by Moonfire NVR itself. However, the interface for adding new cameras is not yet written, so you will have to manually insert cameras with the sqlite3 command line tool prior to starting Moonfire NVR.

Manual commands would look something like this:

$ sudo addgroup --system moonfire-nvr
$ sudo adduser --system moonfire-nvr --home /var/lib/moonfire-nvr
$ sudo mkdir /var/lib/moonfire-nvr
$ sudo -u moonfire-nvr -H mkdir db sample
$ sudo -u moonfire-nvr moonfire-nvr init

Camera configuration and hard drive mounting

If a dedicated hard drive is available, set up the mount point:

$ sudo vim /etc/fstab
$ sudo mount /var/lib/moonfire-nvr/sample

Once setup is complete, it is time to add camera configurations to the database. If the daemon is running, you will need to stop it temporarily:

$ sudo systemctl stop moonfire-nvr

You can configure the system through a text-based user interface:

$ sudo -u moonfire-nvr moonfire-nvr config

In the user interface, add your cameras under the "Edit cameras" dialog. There's a "Test" button to verify your settings directly from the dialog.

After the cameras look correct, go to "Edit retention" to assign disk space to each camera. Leave a little slack (at least 100 MB per camera) between the total limit and the filesystem capacity, even if you store nothing else on the disk. There are several reasons this is needed:

• The limit currently controls fully-written files only. There will be up to two minutes of video per camera of additional video.
• The rotation happens after the limit is exceeded, not proactively.
• Moonfire NVR currently doesn't account for the unused space in the final filesystem block at the end of each file.
• Moonfire NVR doesn't account for the space used for directory listings.
• If a file is open when it is deleted (such as if a HTTP client is downloading it), it stays around until the file is closed. Moonfire NVR currently doesn't account for this.

When finished, start the daemon:

$ sudo systemctl start moonfire-nvr

System Service

Moonfire NVR can be run as a systemd service. If you used prep.sh this has been done for you. If not, Create /etc/systemd/system/moonfire-nvr.service:

[Unit]
Description=Moonfire NVR
After=network-online.target

[Service]
ExecStart=/usr/local/bin/moonfire-nvr run \
    --sample-file-dir=/var/lib/moonfire-nvr/sample \
    --db-dir=/var/lib/moonfire-nvr/db \
    --http-addr=0.0.0.0:8080
Environment=RUST_LOG=info
Type=simple
User=moonfire-nvr
Nice=-20
Restart=on-abnormal
CPUAccounting=true
MemoryAccounting=true
BlockIOAccounting=true

[Install]
WantedBy=multi-user.target

Note that the HTTP port currently has no authentication; it should not be directly exposed to the Internet.

Complete the installation through systemctl commands:

$ sudo systemctl daemon-reload
$ sudo systemctl start moonfire-nvr
$ sudo systemctl status moonfire-nvr
$ sudo systemctl enable moonfire-nvr

See the systemd documentation for more information. The manual pages for systemd.service and systemctl may be of particular interest.

Troubleshooting

While Moonfire NVR is running, logs will be written to stdout. The RUST_LOG environmental variable controls the log level; RUST_LOG=info is recommended. If running through systemd, try sudo journalctl --unit moonfire-nvr to view the logs.

If Moonfire NVR crashes with a SIGSEGV, the problem is likely an incompatible version of the C ffmpeg libraries; use the latest 2.x release instead. This is one of the Rust growing pains mentioned above. While most code written in Rust is "safe", the foreign function interface is not only unsafe but currently error-prone.

Getting help and getting involved

Please email the moonfire-nvr-users mailing list with questions, bug reports, feature requests, or just to say you love/hate the software and why.

I'd welcome help with testing, development (in Rust, JavaScript, and HTML), user interface/graphic design, and documentation. Please email the mailing list if interested. Patches are welcome, but I encourage you to discuss large changes on the mailing list first to save effort.

License

This file is part of Moonfire NVR, a security camera digital video recorder. Copyright (C) 2016 Scott Lamb slamb@slamb.org

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

In addition, as a special exception, the copyright holders give permission to link the code of portions of this program with the OpenSSL library under certain conditions as described in each individual source file, and distribute linked combinations including the two.

You must obey the GNU General Public License in all respects for all of the code used other than OpenSSL. If you modify file(s) with this exception, you may extend this exception to your version of the file(s), but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version. If you delete this exception statement from all source files in the program, then also delete it here.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program. If not, see http://www.gnu.org/licenses/.