libilmbase25 2.5.4-1 (riscv64 binary) in ubuntu impish

 IlmBase are a set of utility libraries released by ILM, and used in
 their OpenEXR implementation. Included in this package you can find:
 .
  * libHalf: a class (Half) for manipulating "half" values (16-bit
    floating point format) as if they were a built-in C++ data type.
 .
  * libIlmThread: a thread abstraction library on top of pthreads.
 .
  * libImath: a math library with support for matrices, 2d- and
    3d-transformations, solvers for linear/quadratic/cubic equations,
    and more.
 .
  * libIex: an exception handling library.