tellopy 📸🎮🐍

Minimal python3 library for reading images from and sending commands to a DJI tello drone.

To build on Windows, install ffmpeg wich chocolatey:

1. install chocolatey
2. open cmd or terminal as administrator
3. choco install

Then install visual studio and build

1. install visual studio
2. open a developer command prompt
3. edit build.bat for your version of python
4. run build.bat to compile the telloc python bindings (libtellopy)

Lastly, pip install tellopy . inside of this repo.

Tellopy is based on on telloc (see below:)

telloc 📸🎮

Cross-platform C library for connecting to the DJI Tello with video support

This was created for the Roadrunner Dynamics Club.

What? 🕹️ 🪟 🍏 🐧

This library supports Windows, MacOS and Linux developers who might want to make cool apps to control their fancy flying robot.

Why? ⁉️

Mostly because existing tello libraries are overly complicated, abandoned, and/or do not work.

This library implements a clean, cross-platform interface for:

• Sending commands and receiving responses
• Receiving video data as RBG images
• Receiving state data as a string

How? 📖

Building the library 🚧👷

To build this library, you simply need to install ffmpeg libraries (avformat, avcodec, avutil, swscale).

Windows:

choco install ffmpeg-shared

MacOS:

brew install ffmpeg

Debian/Ubuntu:

sudo apt install libavformat-dev libavcodec-dev libavutil-dev libswscale-dev

Then you should be able to build telloc with CMake.

mkdir build
cd build
cmake ..
make

telloc also comes with a testing program for Windows / Unix-based systems that will attempt to connect to the drone and display information if successful. And Python3 bindings.

mkdir build
cd build
cmake .. -DBUILD_TESTING=True -DBUILD_PYTHON=True
make

Using the python library 🐍

1. Build The library with python bindings

mkdir build
cd build
cmake .. -DBUILD_PYTHON=True
make

2. Copy libtellopy.so into the tellopy folder

cd ..
cp build/libtellopy.so tellopy

3. Install the python library

cd ..
pip install -e tellopy

Using the library 🪨

telloc has a simple interface defined in telloc.h. You can read main.c for example usage.

telloc spawns three threads when you call telloc_connect(...):

• the state thread - reads state strings and saves them into a buffer.
• the video thread - reads and decodes video data into an RGB image buffer.
• the keepalive thread - sends a keepalive query to the drone once per second.

To attempt a connection and spawn threads, you can run

tello_connection *connection = telloc_connect();

When you want to send data to a successful connection, you do:

char *command="streamon";
char *response=malloc(TELLOC_STATE_SIZE);
int ret_command = telloc_send_command(connection, command, strlen(command), response, TELLOC_STATE_SIZE)
printf("Response was %s\n", response);

To read the most recent video frame, you can do the following:

unsigned char *image = malloc(TELLOC_VIDEO_SIZE);
unsigned int image_bytes;
unsigned int image_width;
unsigned int image_height;
int ret_video = telloc_read_image(connection, image, TELLOC_VIDEO_SIZE, &image_bytes, &image_width, &image_height);
if (ret_video==0)
    printf("Image: %d bytes; %d x %d\n", image_bytes, image_width, image_height);

To read the most recent state string, you can do the following:

char *state = malloc(TELLOC_STATE_SIZE);
int ret_state = telloc_read_state(connection, state, TELLOC_STATE_SIZE);
if (ret_state==0)
    printf("State: %s\n", state);

TODO ✔️

• Use static libraries for ffmepg, build static telloc
• Save binaries somewhere accessible

Release Notes 📝

• 2023-02-18: Improved interface by using opaque struct pointer instead of void*
• 2023-03-04: Added python bindings

License ©️ ❎

This is licenced under the 💥 ⚖️⚖️ Unlicence ⚖️ 🚀, so basically, do whatever you want but please don't sue me.

see LICENSE.