Devfest London- Unlocking Jetpack Media3: Beyond Playback

For many Android developers, Jetpack Media3 is synonymous with ExoPlayer and video playback. But Media3 has grown into a powerful, modular toolkit that can handle everything from real-time video previewing to advanced media transformations — and even custom video editing workflows. In this talk, we’ll go beyond playback and explore the hidden capabilities of Media3: - Frame extraction with the new ExperimentalFrameExtractor for high-quality thumbnails and timeline previews - Editing and effects with Transformer and Effect APIs — from speed changes to overlays - Real-time previewing with CompositionPlayer - Understanding when to use preview vs export workflows Whether you’re building a social media app, a sports highlight editor, or simply want to level up your media handling skills, you’ll leave with a toolkit of ideas (and code) to take Media3 far beyond just playback.

Transcript

1. London Kubra Harmankaya Android Developer Unlocking Jetpack Media3: Beyond Playback 2025
2. Media3 - Overview
3. Media3 - From Fragmentation to Media3
4. Media3 - Home for media libraries
5. Media3 - Minimum supported Android version
7. Media3 - Play Content
9. Media3 - MediaSession
10. Media3 - MediaSessionService Enables your media service to run in the foreground, handling: - Notification management - Playback resumption - Service lifecycle and foreground state management - Resource management
11. MediaSessionService
13. Your “I-can’t-live-without-this” editing action is…
15. Transformer - Editing
16. Media3 - Editing Journey
17. Composition EditedMediaItem MediaItem Effects EditedMediaItemSequence EditedMediaItem EditedMediaItem Video1 Video2 00:00 00:10 00:03
18. Composition EditedMediaItem MediaItem Effects EditedMediaItemSequence EditedMediaItem EditedMediaItem Composition EditedMediaItemSequence EditedMediaItem EditedMediaItem
19. Media3 - Editing Journey
20. Preview with CompositionPlayer
21. Media3 - Editing Journey
26. Media3 - Rotation
27. Media3 - Effects Scan to Read!
29. Media3 - Socialite Hero sample app showcasing our camera and media best practices.
30. Media3 - Socialite demo Scan to Read!
33. CodecDBLite & Performance — What’s the Relationship?
36. Media3 - AI Example
37. Media3 - Frame Extraction Scan to Read!
38. Media3 - AI RealTime Subtitles
39. Media3 - PastPort demo app AI-powered photo time machine, built with Google’s Nano Banana 🍌 Firebase API 🔥
40. Media3 - Vibe effect demo app - Goal: Let users describe a look. Gen AI produce a sequence of video effects to preview instantly. - Key principle: AI does not touch pixels. AI only returns a JSON description of effects. Rendering happens on-device with Media3 + OpenGL.
41. Media3 - Vibe effect demo app - AI layer: Firebase Vertex AI for Android (`GenerativeModel`) calling “gemini-2.5-pro” with a strict JSON schema. - Effect parser: “GenAIEffectParser” turns AI JSON into Media3 `Effect` objects and custom OpenGL effects. - Video engine: Media3 Transformer “CompositionPlayer” plays a “Composition” built from an “EditedMediaItem” + “Effects”. - GPU effects: Media3 “GlEffect”/”GlShaderProgram” for custom GLSL; built-in Media3 effects for common adjustments. Scan for repo!
42. Media3 - Take away
43. Media3 - Take away
44. Media3 - Take away
45. Media3 - Wrap-Up
46. References: Migration guide: https://developer.android.com/media/media3/exoplayer/migration-guide Release notes: https://developer.android.com/jetpack/androidx/releases/media3 goo.gle/media3-demos developer.android.com/media3
47. London Kubra Harmankaya Android Developer Thank you! 2025