AMD engineers have contributed threading fixes to HandBrake that dramatically improve transcoding performance on high-core-count Threadripper systems. The improvements are included in HandBrake 1.11.0 and later.
During testing, AMD found that HandBrake was not scaling well beyond 64 logical processors. On systems with more cores available, performance could actually drop by as much as 60% under some workloads, particularly at lower resolutions where scheduling overhead makes up a larger share of processing time.
Two specific issues were identified. First, HandBrake lacked efficient support for systems with more than 64 logical processors, leaving available CPU resources underused. Second, some workloads were divided into jobs that were too small, generating unnecessary scheduling overhead instead of keeping cores busy with actual transcode work.
AMD proposed fixes addressing both issues, which the HandBrake project accepted and merged upstream. Users on Threadripper systems can get the improvements simply by updating to HandBrake 1.11.0 or newer, with no workflow changes required.
Performance results
AMD tested two systems, both paired with a Radeon RX 9070 XT GPU, comparing HandBrake CLI 1.11.1 against CLI 1.6.1 as the baseline. The older version was chosen to isolate the threading improvements from separate AMF preset changes introduced in later releases.
- On a Ryzen Threadripper PRO 9995WX 96-core system, transcoding performance improved by up to 181% depending on workload. The biggest gains came from H.264 720p (+181%), HEVC 10-bit 4K (+151%), and 8K HEVC content (+149%).
- On a Ryzen Threadripper 7980X 64-core system with 128 GB DDR5-5600 memory, gains reached as high as 215%. H.264 720p saw the largest improvement at +215%, followed by 8K HEVC 8-bit at +203% and 8K 60fps HEVC 10-bit at +105%.
- Across both platforms, improvements ranged from around 16% to 215% depending on codec, resolution, and bit depth.
Bradley Sepos, software engineer and HandBrake project co-lead, acknowledged AMD’s contribution: video encoding remains one of the most compute-intensive workloads, and the HandBrake project welcomes AMD’s continued investment in the open-source ecosystem.
HandBrake 1.11.0 and later are available from the official HandBrake releases page on GitHub.
