---
title: "startAnalysis(of:)"
framework: vision
role: symbol
role_heading: Instance Method
path: "vision/videoprocessor/startanalysis(of:)"
---

# startAnalysis(of:)

Begins analyzing video frames.

## Declaration

```swift
final func startAnalysis(of timeRange: CMTimeRange? = nil)
```

## Parameters

- `timeRange`: The range of video timestamps to process.

## Discussion

Discussion By default the framework processes the entire video.