Update README.md

README.md

@@ -12,7 +12,7 @@ detection labels, and it generates a static HTML webpage with metrics and plots.
 
 #### Features
 
-- Supports all object detection label formats that can be read with [labelformat](https://github.com/lightly-ai/labelformat) package. That includes YOLO, COCO, KITTI, PascalVOC, Lightly and Labelbox.
+- Supports all object detection label formats that can be read with [Labelformat](https://github.com/lightly-ai/labelformat) package. That includes YOLO, COCO, KITTI, PascalVOC, Lightly and Labelbox.
 - Shows the image, object and class counts
 - Analyzes how many images have no labels, and provides their filenames.
 - Shows image samples
@@ -25,19 +25,71 @@ detection labels, and it generates a static HTML webpage with metrics and plots.
 
 See a [live example report](https://lightly-ai.github.io/lightly-insights-preview/) for a small dataset.
 
-## Screenshots
+#### Screenshots
 
 <p float="left">
 <img src="screenshot0.png" width="32%" alt="Lightly Insights Screenshot"/>
 <img src="screenshot1.png" width="32%" alt="Lightly Insights Screenshot"/>
 <img src="screenshot2.png" width="32%" alt="Lightly Insights Screenshot"/>
 </p>
 
+## Installation
+
+```
+pip install lightly-insights
+```
+
 ## Usage
 
-[TODO]
+Lightly Insights report is generated by a python script. This is necessary to support different label formats.
+
+The example below uses [PascalVOC 2007](http://host.robots.ox.ac.uk/pascal/VOC/voc2007/index.html) dataset.
+You can follow the example by downloading it (~450MB):
+
+```
+wget http://host.robots.ox.ac.uk/pascal/VOC/voc2007/VOCtrainval_06-Nov-2007.tar
+tar -xvf VOCtrainval_06-Nov-2007.tar
+```
+
+To run Lightly Insights, we need to provide:
+
+* Image folder. In our case that is `./VOCdevkit/VOC2007/JPEGImages`.
+* Object detection labels. They are ingested as [Labelformat](https://github.com/lightly-ai/labelformat)
+  ObjectDetectionInput class. For PascalVOC the constructor needs the folder with annotations
+  `./VOCdevkit/VOC2007/Annotations` and the list of classes. For other format classes, please
+  refer to [Labelformat formats](https://github.com/lightly-ai/labelformat/blob/main/src/labelformat/formats/__init__.py).
+
+```py
+from pathlib import Path
+from labelformat.formats import PascalVOCObjectDetectionInput
+from lightly_insights import analyze, present
+
+# Analyze an image folder.
+image_analysis = analyze.analyze_images(
+    image_folder=Path("./VOCdevkit/VOC2007/JPEGImages")
+)
+
+# Analyze object detections.
+label_input = PascalVOCObjectDetectionInput(
+    input_folder=Path("./VOCdevkit/VOC2007/Annotations"),
+    category_names=(
+        "person,bird,cat,cow,dog,horse,sheep,aeroplane,bicycle,boat,bus,car,"
+        + "motorbike,train,bottle,chair,diningtable,pottedplant,sofa,tvmonitor"
+    )
+)
+od_analysis = analyze.analyze_object_detections(label_input=label_input)
+
+# Create HTML report.
+present.create_html_report(
+    output_folder=Path("./html_report"),
+    image_analysis=image_analysis,
+    od_analysis=od_analysis,
+)
+```
+
+To view the report, open `./html_report/index.html`.
 
-### Development
+## Development
 
 The library targets python 3.7 and higher. We use poetry to manage the development environment.