In an era when energy efficiency, portability, and AI acceleration are front and centre, Windows 11 AI PCs powered by Snapdragon devices are quickly gaining relevance. To make sure powerful tools like HandBrake stay effective in this evolving landscape, we embarked on a project to optimize HandBrake for Windows on Snapdragon.
HandBrake is a widely used open-source video transcoder, built on FFmpeg, that enables conversion across formats with support for modern codecs and hardware acceleration.
Using a device with a Snapdragon® X Elite processor as a reference platform, our team delivered performance enhancements, hardware acceleration, and upstream contributions spanning multiple open-source video components. HandBrake is powerful, but with Windows on Snapdragon, its performance lagged behind x64 platforms as well as Apple’s ARM64 platforms. This project changed that.
Windows on Snapdragon: The Bigger Picture
Windows on Snapdragon (WoS) is Microsoft’s collaboration with Qualcomm Technologies, Inc. to bring long battery life, always-on connectivity, and AI-powered compute to Windows PCs.
- Snapdragon X Series processors deliver flagship-level performance with integrated CPU, GPU, and NPU.
- Microsoft actively encourages developers to port apps natively for best performance and power efficiency.
With the ecosystem growing fast, optimizing HandBrake for Snapdragon was both a challenge and an opportunity.
Think we should do X Series because his would run across all of the family
Our Approach: Optimizing HandBrake for Snapdragon
Core Technical Contributions
- Hotspot Function Tuning – Rewrote CPU intensive filtering modules that includes comb detect, decomb, scaling, dithering, and colour conversion using NEON intrinsics and assembly for reduced timing overhead.
- Frame Rate Shaper Filter – Optimized the filter algorithm for faster and more efficient processing.
- Encoder Runtime Optimization – Enhanced SVT-AV1 and x265 encoders with runtime ASM detection for Snapdragon CPUs, along with threading and scheduling optimizations.
- 8-bit & 10-bit Pipelines – Tuned for higher throughput and reduced stalls.
- Direct3D 11 Acceleration – Enabled hardware decoding and texture interop to minimize CPU-GPU data transfers.
- Media Foundation Encoders – Activated GPU-assisted encoding for H.264, HEVC, and AV1.
- VideoProcessorBlt Scaling – Offloaded scaling to GPU to eliminate CPU-GPU data transfer bottlenecks.
Profiling & Memory Optimizations
- Used WPA, Profile Explorer, and Instruments (MacOS) for hotspot detection.
- Conducted wait chain analysis to identify thread contention.
- Reduced CPU ↔ GPU transfer overhead, critical for ARM platforms.
UI & Ecosystem Enhancements
- Improved C# / WPF UI responsiveness with Snapdragon-specific optimizations.
- Contributed upstream patches to HandBrake, FFmpeg, SVT-AV1, and x265 for long-term ecosystem impact.
Key Achievements
| Area | Outcome |
|---|---|
|
Performance |
Up to 60% faster transcoding on flagship Snapdragon X Series SoCs |
|
Hardware Acceleration |
GPU-powered encode/decode and scaling |
|
Bit-Depth Optimization |
Enhanced 8-bit & 10-bit video paths |
|
Multi-threading |
Improved AV1 (SVT-AV1) & HEVC (x265) scheduling |
|
Ecosystem Impact |
Contributions merged upstream |
Business Impact
Problem
- High CPU usage and thermal throttling on ARM64
- Lack of hardware acceleration in HandBrake
- Missing NEON-optimized paths for key functions
Solution Highlights
- NEON intrinsics and assembly-level optimizations
- Hardware-accelerated decoding and Media Foundation encoders
- D3D11 VideoProcessorBlt scaling and GPU texture interop
- Smarter threading for heterogeneous Qualcomm OryonTM CPU cores
Impact
- 60% higher transcode FPS on flagship Snapdragon X Series platform
- Up to 2.5x better performance than x64 competitors like Intel Core Ultra Series 2 (Lunar Lake)
- Lower CPU load → improved power efficiency and thermal performance
- Positioned HandBrake as a competitive transcoding tool on PCs with Snapdragon
Why This Matters for the Future
- Tools that are native to Snapdragon are essential as Windows on Snapdragon adoption grows.
- Upstream contributions strengthen the global open-source video ecosystem.
- Better UX & workflows remain future goals.
Conclusion
Optimizing HandBrake for Windows on Snapdragon was not just a technical project, it was a strategic step toward the future of computing.
By combining NEON optimizations, hardware acceleration, threading refinements, and upstream collaboration, we made HandBrake faster, more efficient, and ready for devices with Snapdragon. Now, HandBrake delivers desktop-class transcoding on energy-efficient devices with Snapdragon giving users the speed, quality, and portability they need.