NymphCast – an audio/video casting system with support for custom apps

NymphCast

NymphCast is a software solution which turns your choice of Linux-capable hardware into an audio and video source for a television or powered speakers. It enables the streaming of audio and video over the network from a wide range of client devices, as well as the streaming of internet media to a NymphCast server, controlled by a client device.

In addition, it supports powerful apps (NymphCast apps) written in AngelScript to extend the functionality of NymphCast with a variety of online services.

Goals

• Server (receiver) works on mainstream Linux-capable Single-Board Computers (SBCs), tested on Raspberry Pi 2 (v1.1).

• Streaming of local media to a NymphCast server.

• Sending of URLs, for streaming by the server without client interaction.

• Sending of commands, to control volume, open and control NymphCast apps.

Project layout

The layout of relevant folders in the project is as follows:

/
|- player 	(the NymphCast demonstration client)
|- src/
|	|- client 		(basic NymphCast client, for testing)
|	|- client_lib 	(NymphCast SDK files)
|	|- server		(the NymphCast server and NymphCast app files)
|- tools	(shell scripts for creating releases, in progress)

Player

The NymphCast Player is provided as a demonstration of the NymphCast SDK (see details on the SDK later in the document), allowing one to make use of the basic NymphCast functionality. It is designed to run on any mainstream desktop OS, as well as Android-based smartphones and tablets.

An APK has been made available for installation on Android in the 'releases' section. A desktop release for Windows (x64) is available as well.

Quick Start

This quick start guide assumes building the receiver ( server ) project on a system (like a Raspberry Pi) running a current version of Debian (Buster) or equivalent. The player application can be built on Linux/BSD/MacOS with a current GCC toolchain, or MSYS2 on Windows with MinGW toolchain.

Server

Here two options are possible:

setup.sh
install_linux.sh

Or:

1. Follow the instructions in the 'Building' section.

Player

For Windows (x64):

1. Download and extract the binary release.

Or (Windows & other platforms):

1. Build the libnymphcast library in the src/client_lib folder using the Makefile in that folder: make lib .
2. Install the newly created library under lib/ into /usr/local/lib or equivalent.
3. Copy the nymphcast_client.h header to /usr/local/include or equivalent.
4. Ensure the Qt5 dependency is installed.
5. Create player/NymphCastPlayer/build folder and change into it.
6. Execute qmake .. followed by make .
7. Binary is created either in the same build folder or in a debug/ sub-folder.
8. Execute the binary to open the player.
9. Connect to the server instance using its IP address.
10. Cast a media file or URL.

Platforms

The server targets SBCs, but like the client (and SDK) should work on any platform that supports a C++17 toolchain and is supported by the LibPoco dependency:

• Windows XP+
• MacOS
• Linux (desktop & embedded)
• Solaris
• *BSD
• HP-UX
• AIX
• QNX
• VxWorks
• Android
• iOS
• Windows Embedded

The server relies on the FFmpeg library, which is supported on a wide variety of platforms, with Linux, MacOS and Windows being the primary platforms.

Releases

NymphCast is currently in Alpha stage, with experimental releases being made available on Github (see the ' releases ' section).

Building

To build NymphCast, one needs the following dependencies in addition to a C++ toolchain with C++17 support.

Run the Makefile in the client and server folders, which should output a binary into the newly created bin/ folder.

Server:

Dependencies:

• NymphRPC
• LibAV (v4+)
• LibSDL2
• LibPOCO (1.5+)

On Debian & derivatives:

1. Install the needed dependencies: sudo apt -y install libsdl2-image-dev libsdl2-dev libpoco-dev and sudo apt -y install libswscale-dev libavcodec-dev libavdevice-dev libavformat-dev libavutil-dev libpostproc-dev libswresample-dev
2. Check-out NymphRPC elsewhere and build the library with make lib .
3. Copy the NymphRPC library from NymphRPC/lib/ to /usr/local/lib .
4. Create /usr/local/include/nymph folder. Perform sudo cp src/*.h /usr/local/include/nymph .
5. Change to NymphCast/src/server and execute make command.
6. The server binary is found under bin/ . Copy the *.jpg images into the bin folder for the screensaver feature.
7. Copy the nymphcast_config.ini file into bin/ as well.
8. Copy the apps/ folder into the bin/ ' folder.
9. Simply execute the binary to have it start listening on port 4004: ./nymphcast_server -c nymphcast_config.ini .

Client dependencies

• NymphRPC
• LibPOCO (1.5+)

Running

The server binary can be started as-is, and will listen on all network interfaces for incoming connections.

The client binary has to be provided with the filename of a media file that should be sent to the remote server, with an optional IP address of the remote server:

$ nymphcast_client <filename>
$ nymphcast_client <IP> <filename>

Limitations

• The server is assumed to have 100 MB heap space free for caching.
• Remote seeking support is not enabled yet, meaning MP4 files <100 MB with the header at the end do not work yet.

SDK

An SDK has been made available in the src/client_lib/ folder. The player project under player/ uses the SDK as part of a Qt5 project to implement a NymphCast client which exposes all of the NymphCast features to the user.

To use the SDK, the Makefile in the SDK folder can be executed with a simple make command, after which a library file can be found in the src/client_lib/lib folder.

Note:to compile the SDK, both NymphRPC and LibPOCO (1.5+) must be installed.

After this the only files needed by a client project are this library file and the nymphcast_client.h header file.