Viewing Inference Results in a Terminal
Image from the libsixel website.
Motivation
When connecting to a remote machine, normally visualizing image results is not possible or requires moving data to a local device with a GUI. The VSCode integrated terminal allows for directly rendering images. This is a short demonstration on how to use this in conjunction with ultralytics
with prediction results.
Warning
Only compatible with Linux and MacOS. Check the VSCode repository, check Issue status, or documentation for updates about Windows support to view images in terminal with sixel
.
The VSCode compatible protocols for viewing images using the integrated terminal are sixel
and iTerm
. This guide will demonstrate use of the sixel
protocol.
Process
-
First, you must enable settings
terminal.integrated.enableImages
andterminal.integrated.gpuAcceleration
in VSCode."terminal.integrated.gpuAcceleration": "auto" # "auto" is default, can also use "on" "terminal.integrated.enableImages": false
-
Install the
python-sixel
library in your virtual environment. This is a fork of thePySixel
library, which is no longer maintained. -
Load a model and execute inference, then plot the results and store in a variable. See more about inference arguments and working with results on the predict mode page.
from ultralytics import YOLO # Load a model model = YOLO("yolo11n.pt") # Run inference on an image results = model.predict(source="ultralytics/assets/bus.jpg") # Plot inference results plot = results[0].plot() # (1)!
- See plot method parameters to see possible arguments to use.
-
Now, use OpenCV to convert the
numpy.ndarray
tobytes
data. Then useio.BytesIO
to make a "file-like" object.import io import cv2 # Results image as bytes im_bytes = cv2.imencode( ".png", # (1)! plot, )[1].tobytes() # (2)! # Image bytes as a file-like object mem_file = io.BytesIO(im_bytes)
- It's possible to use other image extensions as well.
- Only the object at index
1
that is returned is needed.
-
Create a
SixelWriter
instance, and then use the.draw()
method to draw the image in the terminal.
Example Inference Results
Danger
Using this example with videos or animated GIF frames has not been tested. Attempt at your own risk.
Full Code Example
import io
import cv2
from sixel import SixelWriter
from ultralytics import YOLO
# Load a model
model = YOLO("yolo11n.pt")
# Run inference on an image
results = model.predict(source="ultralytics/assets/bus.jpg")
# Plot inference results
plot = results[0].plot() # (3)!
# Results image as bytes
im_bytes = cv2.imencode(
".png", # (1)!
plot,
)[1].tobytes() # (2)!
mem_file = io.BytesIO(im_bytes)
w = SixelWriter()
w.draw(mem_file)
- It's possible to use other image extensions as well.
- Only the object at index
1
that is returned is needed. - See plot method parameters to see possible arguments to use.
Tip
You may need to use clear
to "erase" the view of the image in the terminal.
FAQ
How can I view YOLO inference results in a VSCode terminal on macOS or Linux?
To view YOLO inference results in a VSCode terminal on macOS or Linux, follow these steps:
-
Enable the necessary VSCode settings:
-
Install the sixel library:
-
Load your YOLO model and run inference:
-
Convert the inference result image to bytes and display it in the terminal:
For further details, visit the predict mode page.
Why does the sixel protocol only work on Linux and macOS?
The sixel protocol is currently only supported on Linux and macOS because these platforms have native terminal capabilities compatible with sixel graphics. Windows support for terminal graphics using sixel is still under development. For updates on Windows compatibility, check the VSCode Issue status and documentation.
What if I encounter issues with displaying images in the VSCode terminal?
If you encounter issues displaying images in the VSCode terminal using sixel:
-
Ensure the necessary settings in VSCode are enabled:
-
Verify the sixel library installation:
-
Check your image data conversion and plotting code for errors. For example:
If problems persist, consult the VSCode repository, and visit the plot method parameters section for additional guidance.
Can YOLO display video inference results in the terminal using sixel?
Displaying video inference results or animated GIF frames using sixel in the terminal is currently untested and may not be supported. We recommend starting with static images and verifying compatibility. Attempt video results at your own risk, keeping in mind performance constraints. For more information on plotting inference results, visit the predict mode page.
How can I troubleshoot issues with the python-sixel
library?
To troubleshoot issues with the python-sixel
library:
-
Ensure the library is correctly installed in your virtual environment:
-
Verify that you have the necessary Python and system dependencies.
-
Refer to the python-sixel GitHub repository for additional documentation and community support.
-
Double-check your code for potential errors, specifically the usage of
SixelWriter
and image data conversion steps.
For further assistance on working with YOLO models and sixel integration, see the export and predict mode documentation pages.