libsvtav1 Shared Library Binary File Size

This article provides a detailed breakdown of the expected binary file size of the natively compiled libsvtav1 shared library. It explores the typical sizes for both the encoder and decoder libraries on standard platforms, while highlighting the primary factors—such as compiler optimization, assembly instruction sets, and debugging symbols—that influence the final footprint of the compiled binaries.

Expected Size of libsvtav1 Shared Libraries

When compiled natively on a modern 64-bit operating system (such as Linux x86_64) using default production settings, the SVT-AV1 codebase produces two main shared libraries: the encoder (libSvtAv1Enc) and the decoder (libSvtAv1Dec).

Under standard Release build configurations, the expected sizes for stripped binaries are:

• libSvtAv1Enc.so (Encoder): 5 MB to 9 MB The encoder is the larger of the two libraries due to extensive mathematical analysis algorithms, look-ahead logic, and highly optimized vectorization code paths.
• libSvtAv1Dec.so (Decoder): 1 MB to 2 MB The decoder library has a significantly smaller footprint because its function is strictly limited to parsing and reconstructing the compressed bitstream.

Key Factors Influencing Binary Size

The actual size of your compiled libsvtav1 shared library will vary based on several build parameters:

1. Build Type and Debug Symbols

• Release Build: Compiling with -DCMAKE_BUILD_TYPE=Release optimizes the code for execution speed and reduces file size.
• Debug Build: Compiling with -DCMAKE_BUILD_TYPE=Debug includes extensive symbol tables and disables optimization. This can cause the encoder library size to swell to 50 MB to 100 MB or more.
• Symbol Stripping: Running the strip command (e.g., strip --strip-unneeded libSvtAv1Enc.so) after a release build can shave off an additional 10% to 30% of the file size by removing non-essential debugging structures.

2. Assembly Optimizations

SVT-AV1 utilizes deep hardware acceleration via assembly code (using NASM) for x86_64 (AVX2, AVX-512) and ARM (NEON) architectures. * With Assembly (Default): Including these assembly optimizations increases the binary size because multiple optimized execution paths are bundled into the library. * Without Assembly: Disabling assembly optimizations via -DENABLE_AVX512=OFF or compiling purely in C (-DNEON=OFF on ARM) will result in a smaller binary size, though at a massive cost to encoding performance.

3. Compiler and Toolchain

• GCC vs. Clang: GCC typically produces slightly larger binaries with aggressive loop unrolling, while Clang often produces marginally tighter shared libraries depending on the exact optimization flags passed (e.g., -O3 versus -Os).
• Windows (MSVC) vs. Linux (GCC): On Windows, the compiled Dynamic Link Libraries (SvtAv1EncApp.dll) generally fall within a similar 6 MB to 10 MB range when compiled with Visual Studio in Release mode.