Terminalcast

Command line tool to cast local video files to your chromecast.

Inspired by https://github.com/keredson/gnomecast

Supported media types

Checkout https://developers.google.com/cast/docs/media for your Chromecast model.

Use ffmpeg to convert unsupported files to a supported format:

ffmpeg -i '{input_file}' -metadata title="{title}" -map 0 -c:v {video_codec} -c:a {audio_codec} -c:s copy '{output_file}'

Supported Chromecast versions

In principle this should work with any Chromecast which is supported by https://github.com/home-assistant-libs/pychromecast.

In practice, I discovered that a Chromecast with Google TV enables you to control the player via the remote control, which is very nice.

Installation

pip install terminalcast

Usage

Basic Usage

terminalcast my_video.mp4

Port Configuration

By default, a random free port is chosen. You can specify a fixed port if needed (e.g. for firewall rules):

terminalcast my_video.mp4 --port 8080

Alternatively, set the environment variable TERMINALCAST_PORT:

export TERMINALCAST_PORT=8080
terminalcast my_video.mp4

Reverse Proxy / Custom URL

If you are running terminalcast behind a reverse proxy (e.g. Nginx, Traefik) and want to expose the video via a specific full URL:

terminalcast my_video.mp4 --video-url https://my-server.com/cast/video

Alternatively, set the environment variable TERMINALCAST_VIDEO_URL:

export TERMINALCAST_VIDEO_URL="https://my-server.com/cast/video"
terminalcast my_video.mp4

Note: You must ensure that your proxy forwards requests from this URL to the local terminalcast server (default path is /video).

Known Hosts

If network discovery fails (e.g. due to network restrictions), you can specify known Chromecast IPs:

terminalcast my_video.mp4 --known-hosts 192.168.1.50,192.168.1.51

Alternatively, set the environment variable TERMINALCAST_KNOWN_HOSTS:

export TERMINALCAST_KNOWN_HOSTS="192.168.1.50,192.168.1.51"
terminalcast my_video.mp4

Temporary File Location

When selecting a different audio track, a temporary file is created. To speed this up, you can specify a directory for these files, ideally a RAM disk. A progress bar will be shown during this process.

The default priority is:

1. TERMINALCAST_TMP_DIR environment variable
2. /dev/shm (RAM disk on Linux)
3. /var/tmp
4. System default

Example:

export TERMINALCAST_TMP_DIR="/my/fast/disk"
terminalcast my_video.mp4 --audio-title "English"

Using as a Library

You can also use terminalcast as a library in your own projects. Environment variables like TERMINALCAST_PORT or TERMINALCAST_KNOWN_HOSTS are automatically respected.

from terminalcast import FileMetadata, TerminalCast, create_tmp_video_file

# 1. Get file metadata
filepath = "my_video.mp4"
media_file = FileMetadata(filepath=filepath)
print(media_file.details())

# 2. Select an audio stream (e.g., the first one)
audio_stream = media_file.audio_streams[0]

# 3. (Optional) Create a temporary file if a different audio track is needed
# This shows a progress bar and can take a callback for progress updates
def my_progress_callback(progress: float):
    print(f"Conversion progress: {progress:.2f}%")

tmp_filepath = create_tmp_video_file(
    filepath=filepath,
    audio_index=audio_stream.index[-1:],
    duration=media_file.duration,
    progress_callback=my_progress_callback
)

# 4. Initialize TerminalCast
# You can pass known_hosts as a list of IPs and a specific port,
# or rely on environment variables.
tcast = TerminalCast(
    filepath=tmp_filepath or filepath,
    select_ip=False,  # or True for interactive selection, or a specific IP string
    # known_hosts=["192.168.1.50"],  # Optional: overrides env var
    # port=8080,                     # Optional: overrides env var
    # video_url="..."                # Optional: overrides env var
)

# 5. Start the server and play
print(f"Casting to: {tcast.cast.cast_info.friendly_name}")
tcast.start_server()
tcast.play_video()

# The video is now playing. The script will block here until playback is active.
# You might want to add logic to handle server shutdown, etc.

Contributing

Contributions are welcome! To set up your development environment:

1. Clone the repository
2. Install dependencies: This will install the project in editable mode with all development tools.

   make install
   

3. Install the pre-commit hook: This will run quick checks before each commit.

   pre-commit install
   

4. Run all checks: You can run all linters, type checks, and tests manually at any time.

   make check
   

How is it working?

Terminalcast creates a little HTTP Server at your current machine and serves your media file there. Then it tells the Chromecast the play the stream served at your IP with the corresponding path. That's it! (The devil is in the details.)

Terminalcast uses Bottle to create a small app providing the media file. This app is served by Waitress.

On the other hand Terminalcast detects and plays the media via PyChromecast.

For file information and conversion ffmpeg-python is used.