SVT-AV1 vs rav1e: Encoding Speed and Memory Usage

This article compares the SVT-AV1 (libsvtav1) and rav1e AV1 video encoders, focusing specifically on their performance in terms of encoding speed and system memory usage. By analyzing how each encoder manages hardware resources, you will be able to determine which library is best suited for your video transcoding pipelines and hardware configurations.

Encoding Speed

When it comes to raw encoding speed, SVT-AV1 is the clear winner, especially on modern multi-core processors.

• Parallelization: SVT-AV1 (Scalable Video Technology for AV1) was designed from the ground up by Intel and the Alliance for Open Media to scale efficiently across multiple CPU cores and threads. It utilizes architectural features like AVX2 and AVX-512 instruction sets to accelerate processing.
• Preset Scaling: SVT-AV1 offers a wide range of speed presets (typically from 0 to 13). The higher presets (Preset 8 and above) deliver real-time or faster-than-real-time encoding speeds on consumer hardware while maintaining competitive visual quality.
• rav1e Performance: Developed in Rust by the Xiph.Org Foundation, rav1e focuses on safety and code correctness. While it has made significant speed improvements, it generally processes video much slower than SVT-AV1. Its multi-threading capabilities do not scale as efficiently across high-core-count CPUs, making it less ideal for time-sensitive, high-volume encoding tasks.

Memory Usage (RAM)

In terms of memory efficiency, rav1e holds a significant advantage over SVT-AV1.

• rav1e Footprint: Because rav1e is written in Rust, it benefits from strict memory management guarantees. It maintains a highly predictable, low memory footprint during the encoding process. This makes rav1e ideal for resource-constrained environments, such as low-power edge devices, older servers, or containerized environments with strict memory limits.
• SVT-AV1 Consumption: SVT-AV1 is notorious for its high memory consumption. Because it heavily parallelizes the encoding process by dividing frames into multiple segments processed simultaneously, RAM usage scales up rapidly with the resolution of the video (e.g., 4K vs. 1080p) and the number of CPU threads allocated. On high-core systems encoding 4K video, SVT-AV1 can easily consume several gigabytes of RAM.

Summary: Which Should You Choose?

• Choose SVT-AV1 (libsvtav1) if your priority is encoding speed, throughput, and you are running the software on modern multi-core server or desktop hardware where RAM is plentiful. It is currently the industry standard for practical, CPU-based AV1 encoding.
• Choose rav1e if you are deploying to memory-constrained environments, virtual machines with limited RAM allocations, or systems where stability and low resource overhead are more critical than raw encoding speed.