Oriented Bounding Boxes Object Detection
Oriented object detection goes a step further than object detection and introduce an extra angle to locate objects more accurate in an image.
The output of an oriented object detector is a set of rotated bounding boxes that exactly enclose the objects in the image, along with class labels and confidence scores for each box. Object detection is a good choice when you need to identify objects of interest in a scene, but don't need to know exactly where the object is or its exact shape.
Tip
YOLO11 OBB models use the -obb
suffix, i.e. yolo11n-obb.pt
and are pretrained on DOTAv1.
Watch: Object Detection using Ultralytics YOLO Oriented Bounding Boxes (YOLO-OBB)
Visual Samples
Ships Detection using OBB | Vehicle Detection using OBB |
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Models
YOLO11 pretrained OBB models are shown here, which are pretrained on the DOTAv1 dataset.
Models download automatically from the latest Ultralytics release on first use.
Model | size (pixels) | mAPtest 50 | Speed CPU ONNX (ms) | Speed T4 TensorRT10 (ms) | params (M) | FLOPs (B) |
---|---|---|---|---|---|---|
YOLO11n-obb | 1024 | 78.4 | 117.6 ± 0.8 | 4.4 ± 0.0 | 2.7 | 17.2 |
YOLO11s-obb | 1024 | 79.5 | 219.4 ± 4.0 | 5.1 ± 0.0 | 9.7 | 57.5 |
YOLO11m-obb | 1024 | 80.9 | 562.8 ± 2.9 | 10.1 ± 0.4 | 20.9 | 183.5 |
YOLO11l-obb | 1024 | 81.0 | 712.5 ± 5.0 | 13.5 ± 0.6 | 26.2 | 232.0 |
YOLO11x-obb | 1024 | 81.3 | 1408.6 ± 7.7 | 28.6 ± 1.0 | 58.8 | 520.2 |
- mAPtest values are for single-model multiscale on DOTAv1 dataset.
Reproduce byyolo val obb data=DOTAv1.yaml device=0 split=test
and submit merged results to DOTA evaluation. - Speed averaged over DOTAv1 val images using an Amazon EC2 P4d instance.
Reproduce byyolo val obb data=DOTAv1.yaml batch=1 device=0|cpu
Train
Train YOLO11n-obb on the DOTA8 dataset for 100 epochs at image size 640. For a full list of available arguments see the Configuration page.
Example
from ultralytics import YOLO
# Load a model
model = YOLO("yolo11n-obb.yaml") # build a new model from YAML
model = YOLO("yolo11n-obb.pt") # load a pretrained model (recommended for training)
model = YOLO("yolo11n-obb.yaml").load("yolo11n.pt") # build from YAML and transfer weights
# Train the model
results = model.train(data="dota8.yaml", epochs=100, imgsz=640)
# Build a new model from YAML and start training from scratch
yolo obb train data=dota8.yaml model=yolo11n-obb.yaml epochs=100 imgsz=640
# Start training from a pretrained *.pt model
yolo obb train data=dota8.yaml model=yolo11n-obb.pt epochs=100 imgsz=640
# Build a new model from YAML, transfer pretrained weights to it and start training
yolo obb train data=dota8.yaml model=yolo11n-obb.yaml pretrained=yolo11n-obb.pt epochs=100 imgsz=640
Watch: How to Train Ultralytics YOLO-OBB (Oriented Bounding Boxes) Models on DOTA Dataset using Ultralytics HUB
Dataset format
OBB dataset format can be found in detail in the Dataset Guide.
Val
Validate trained YOLO11n-obb model accuracy on the DOTA8 dataset. No arguments are needed as the model
retains its training data
and arguments as model attributes.
Example
from ultralytics import YOLO
# Load a model
model = YOLO("yolo11n-obb.pt") # load an official model
model = YOLO("path/to/best.pt") # load a custom model
# Validate the model
metrics = model.val(data="dota8.yaml") # no arguments needed, dataset and settings remembered
metrics.box.map # map50-95(B)
metrics.box.map50 # map50(B)
metrics.box.map75 # map75(B)
metrics.box.maps # a list contains map50-95(B) of each category
Predict
Use a trained YOLO11n-obb model to run predictions on images.
Example
Watch: How to Detect and Track Storage Tanks using Ultralytics YOLO-OBB | Oriented Bounding Boxes | DOTA
See full predict
mode details in the Predict page.
Export
Export a YOLO11n-obb model to a different format like ONNX, CoreML, etc.
Example
Available YOLO11-obb export formats are in the table below. You can export to any format using the format
argument, i.e. format='onnx'
or format='engine'
. You can predict or validate directly on exported models, i.e. yolo predict model=yolo11n-obb.onnx
. Usage examples are shown for your model after export completes.
Format | format Argument | Model | Metadata | Arguments |
---|---|---|---|---|
PyTorch | - | yolo11n-obb.pt | ✅ | - |
TorchScript | torchscript | yolo11n-obb.torchscript | ✅ | imgsz , optimize , batch |
ONNX | onnx | yolo11n-obb.onnx | ✅ | imgsz , half , dynamic , simplify , opset , batch |
OpenVINO | openvino | yolo11n-obb_openvino_model/ | ✅ | imgsz , half , int8 , batch |
TensorRT | engine | yolo11n-obb.engine | ✅ | imgsz , half , dynamic , simplify , workspace , int8 , batch |
CoreML | coreml | yolo11n-obb.mlpackage | ✅ | imgsz , half , int8 , nms , batch |
TF SavedModel | saved_model | yolo11n-obb_saved_model/ | ✅ | imgsz , keras , int8 , batch |
TF GraphDef | pb | yolo11n-obb.pb | ❌ | imgsz , batch |
TF Lite | tflite | yolo11n-obb.tflite | ✅ | imgsz , half , int8 , batch |
TF Edge TPU | edgetpu | yolo11n-obb_edgetpu.tflite | ✅ | imgsz |
TF.js | tfjs | yolo11n-obb_web_model/ | ✅ | imgsz , half , int8 , batch |
PaddlePaddle | paddle | yolo11n-obb_paddle_model/ | ✅ | imgsz , batch |
MNN | mnn | yolo11n-obb.mnn | ✅ | imgsz , batch , int8 , half |
NCNN | ncnn | yolo11n-obb_ncnn_model/ | ✅ | imgsz , half , batch |
IMX500 | imx | yolo11n-obb_imx_model/ | ✅ | imgsz , int8 |
See full export
details in the Export page.
FAQ
What are Oriented Bounding Boxes (OBB) and how do they differ from regular bounding boxes?
Oriented Bounding Boxes (OBB) include an additional angle to enhance object localization accuracy in images. Unlike regular bounding boxes, which are axis-aligned rectangles, OBBs can rotate to fit the orientation of the object better. This is particularly useful for applications requiring precise object placement, such as aerial or satellite imagery (Dataset Guide).
How do I train a YOLO11n-obb model using a custom dataset?
To train a YOLO11n-obb model with a custom dataset, follow the example below using Python or CLI:
Example
For more training arguments, check the Configuration section.
What datasets can I use for training YOLO11-OBB models?
YOLO11-OBB models are pretrained on datasets like DOTAv1 but you can use any dataset formatted for OBB. Detailed information on OBB dataset formats can be found in the Dataset Guide.
How can I export a YOLO11-OBB model to ONNX format?
Exporting a YOLO11-OBB model to ONNX format is straightforward using either Python or CLI:
Example
For more export formats and details, refer to the Export page.
How do I validate the accuracy of a YOLO11n-obb model?
To validate a YOLO11n-obb model, you can use Python or CLI commands as shown below:
Example
See full validation details in the Val section.