libyuv is an open source project that includes YUV scaling and conversion
functionality.

- Prepare content for compression, with point, bilinear or box filter.
- Convert to YUV from webcam formats.
- Convert from YUV to formats for rendering/effects.
- Rotate by 90/180/270 degrees to adjust for mobile devices in portrait mode.
- Optimized versions for SSE2/SSSE3/AVX2 on x86/x64,
  Neon on Arm, DSP R2 Mips are possible.

WWW: https://chromium.googlesource.com/libyuv/libyuv/