Platform requirements

  • Requires zlib or a zlib-compatible library
  • Fixed width integer types up to (u)int32_t
  • Integers must be two’s complement.
  • CHAR_BIT must equal 8.
  • size_t must be unsigned and at least 32-bit, 16-bit platforms are not supported.

Build with CMake

mkdir cbuild
cd cbuild
cmake ..
make install

Build with Meson

meson build
cd build
ninja install


Architecture-specific optimizations are enabled by default, this can be disabled with the SPNG_DISABLE_OPT compiler option.

The Meson project has an enable_opt option, it is enabled by default, the CMake equivalent is ENABLE_OPT.

Optimizations on x86 require SSE2 by default, to enable SSSE3 optimizations add -DSPNG_SSE=3 as a compiler option, this improves performance by up to 7%.

Compiler-specific macros are used to omit the need for the -msse2 and -mssse3 compiler flags, if the code does not compile without these flags you should file a bug report.

Profile-guided optimization

Profile-guided optimization (PGO) improves performance by up to 10%.

# Run in root directory
git clone
cd build
meson configure -Dbuildtype=release --default-library both -Db_pgo=generate
./example ../benchmark_images/medium_rgb8.png
./example ../benchmark_images/medium_rgba8.png
./example ../benchmark_images/large_palette.png
meson configure -Db_pgo=use
ninja install