True Drive CLI

True Drive stores files as noise videos, so that any platform that hosts video can double as file storage. This is its command-line tool: it encodes files to video and decodes them back, using the True Drive Core library.

Warning

Videos are not encrypted. Anyone with the video and this tool can recover the file, so encrypt anything sensitive before encoding it.

Requirements

• gcc, CMake 3.21 or newer, and git to build (MSYS2 is one way to get them on Windows)
• FFmpeg 5.1 or newer on your PATH at run time

Build

The core library is a git submodule in modules/core/, so fetch it first:

git submodule update --init
cmake -B build
cmake --build build

This builds the library and produces build/truedrive, or build/truedrive.exe on Windows. To build against a different checkout of the library, add -DTRUEDRIVE_CORE_DIR=<path> to the first cmake command.

Using a container

This opens a shell in an Alpine container that has the compiler, CMake, and FFmpeg installed, with the repository mounted at /app:

docker build -f .devcontainer/Containerfile.dev -t truedrive-cli-dev .devcontainer
docker run -it --rm -v "$PWD":/app truedrive-cli-dev

If you use Podman, replace docker with podman. In Git Bash on Windows, put MSYS_NO_PATHCONV=1 before docker run.

Using VS Code

The repository includes a dev container with the same tools, plus gdb, git, and the C/C++ extension.

1. Install the Dev Containers extension.
2. If you use Podman, set dev.containers.dockerPath to podman in your VS Code user settings.
3. Run Dev Containers: Reopen in Container from the Command Palette.

Then use the VS Code terminal to run the build commands above and the commands below.

Usage

truedrive <encode|decode> -i <input file> -o <output path>

The examples below use the Linux binary. On Windows, run .\build\truedrive.exe instead.

Encode a file

mkdir out
./build/truedrive encode -i input.txt -o out/video

This creates out/video.mkv. Leave the extension off the -o path, since it is added for you. An existing video is never replaced, so encoding fails if out/video.mkv already exists.

Decode a video

./build/truedrive decode -i out/video.mkv -o out/restored.txt

The video only stores the file's contents, not its name, so give -o the full file name you want, including the extension. An existing file with that name is replaced.

Intermediate files

Each run creates a true_drive_encode_<timestamp> or true_drive_decode_<timestamp> folder next to the output, containing the video's frames. These folders are kept after the run and can be deleted by hand. Encoding a 2 MiB file leaves about 2.6 MB behind.

Exit status

The command exits with 0 on success and 1 on failure, with the reason printed to standard error.

Tests

ctest --test-dir build --output-on-failure

The tests need FFmpeg and a POSIX shell. To also check for memory errors, use a toolchain that includes the address and undefined-behavior sanitizers:

cmake -B build/sanitize -DTRUEDRIVE_SANITIZE=ON
cmake --build build/sanitize
ctest --test-dir build/sanitize --output-on-failure

Known limitations

• The folder that -o points into must already exist.
• Input files must be smaller than 64 MiB.
• Only .mkv videos can be decoded.
• On Windows, paths can't contain " or %.
• There is no error correction, so decoding needs every pixel to be intact. Platforms such as YouTube re-compress uploads, which makes decoding fail.
• Videos are stored as PNG images inside Matroska, which many media players and upload sites don't support.
• Videos made by earlier versions, which ended in red pixels, can't be decoded.

License

Apache License 2.0