Library functions

• Edit statusSet() in v2 so that it updates previous line number and error code only if function changes.
• Make interpolation and integration functions that consider frames as step functions; it will keep frames independent on each other.
• Add support for NIfTI-2, see https://nifti.nimh.nih.gov/nifti-2/
• Add attribute((fallthrough)); to all switch fallthrough cases, after all compilers support that.
• Errors etc into common struct from all functions?
• Rename all functions, globals, and most structures with tpc*.
• Large File Support (LFS) for all input/output functions.
• Use Halton quasi-random sequence in population optimization and Monte Carlo simulations.
• All image processing functions should work with pixel values that are NaN or Inf, because SPM saves NIfTI with NaNs.

Applications

• Move necessary applications from the old TPC C libraries to v1 or v2.
• rescoll should have option to save data as CSV table(s).
• Replace upet2e7 with upet2nii.
• When CT image is saved as NIfTI, use 2-byte short ints to reduce file size.
• Add rFRTM by Mandeville et al (2016).

Tests

• Use CMakeLists.txt in v2/libtpctac and v1/ecat as templates for others; then updated test data and scripts will be automatically updated during build.
• Test interpolation functions using realistic PET TTAC functions, including gaps and overlaps.
• Test the quantitativity of BF-programs with very wide range of frames.

Bugs to fix

• Use fixed-width integer types with data formats that are dependent on those.
• Rewrite byte conversion functions to use fixed-width integer types.

C99, C23, and POSIX

• C23 mode is the default since GCC 15; it can be explicitly selected with the -std=gnu23 command-line flag to enable GNU extensions.
• Required: C99 and basic POSIX compatibility. That means also that Visual Studio is not supported (I guess).
• Structures can be copied directly with = but pointer addresses are copied too so pointer contents must be copied with for().
• Structure contents are automatically initiated to 0 and NULL; make sure that it works in Windows and Linux.
• Forget about own strncasecmp(), strdup(), etc.
• Structure tag and typedef can (and should) be the same: typedef struct TAC {int a; double b;} TAC;
• Make sure everything is thread safe in v2.

Security

• Replace all sprintf()'s with snprintf(), or (v)asprintf() (from _GNU_SOURCE).
• Replace strncpy() with strlcpy(); automatically NULL terminated.
• Replace strncat() with strlcat(); automatically NULL terminated.
• Replace all strtok() calls with something else because strtok() is not thread-safe (unless it becomes thread-safe with new compiler versions).