Real-Time Text Recognition (OCR) in Video Calls with ML Kit – WebRTC + ML Kit Android (Part 4)
🔤 In Part 4, we integrate ML Kit's Text Recognition (OCR) API into the live WebRTC video stream. Every camera frame is processed through the ML Kit OCR engine before being encoded and sent to the remote peer — letting you overlay recognized text directly on the live video feed in real time.
📂 Source Code
🔗 https://github.com/codewithkael/WebRT...
📺 Full Playlist
🔗 • WebRTC With AI Image Processing (ML KIT)
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0:00 Episode Overview & OCR Demo
0:40 Adding ML Kit Text Recognition Dependency
1:15 TextRecognitionEffect Class Setup
2:00 Converting VideoFrame to Bitmap for ML Kit
2:50 Running ML Kit Text Recognizer on Each Frame
3:30 Drawing Recognized Text Overlay on Bitmap
4:10 Converting Processed Bitmap Back to VideoFrame
4:50 Adding OCR Toggle to FilterStorage & FilterUIState
5:40 Wiring OCR into the WebRTC Frame Pipeline
6:30 Adding OCR Switch to Filters Dialog
7:10 Live Test: Real-Time OCR Overlay in Video Call
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🎯 What This Episode Covers
ML Kit Text Recognition API integration with WebRTC
VideoFrame → Bitmap → OCR → Overlay → VideoFrame pipeline
Drawing recognized text blocks on live video frames
Toggling OCR on/off at runtime from the filter menu
Performance considerations for per-frame OCR processing
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🧠 AI Frame Processing Pipeline
1. Camera → WebRTC VideoFrame (I420/YUV)
2. Convert to Bitmap (ARGB)
3. Run ML Kit Text Recognition
4. Draw text overlay on Bitmap
5. Convert back to VideoFrame → stream to remote peer
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🛠 Technologies Used
Kotlin & Jetpack Compose
WebRTC Android SDK
Firebase Realtime Database
Google ML Kit Text Recognition API
Kotlin Coroutines
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#WebRTC #AndroidDevelopment #MLKit #TextRecognition #OCR #Kotlin #JetpackCompose #AIVideoFilters #AndroidOCR #RealTimeOCR #VideoCallingApp #CodeWithKael