read.dfa 2.0 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859
  1. # read.dfa
  2. # Build time configuration of libpng
  3. #
  4. # Author: John Bowler
  5. # Copyright: (c) John Bowler, 2013
  6. # Usage rights:
  7. # To the extent possible under law, the author has waived all copyright and
  8. # related or neighboring rights to this work. This work is published from:
  9. # United States.
  10. #
  11. # Build libpng with basic read support. This enables the lowest level libpng
  12. # read API - the one where the calling code has to use a loop to read each row.
  13. # At present this is the API used by most programs.
  14. #
  15. # Support is enabled only for those chunks and transformations that are
  16. # typically required - others can be added easily.
  17. #
  18. everything = off
  19. # The sequential read code is enabled here; the progressive code can be used
  20. # instead but there is no point enabling both.
  21. option SEQUENTIAL_READ on
  22. # Likewise it is pointless enabling both fixed and floating point APIs. Choose
  23. # one or the other for both the API and the internal math.
  24. #Fixed point:
  25. #option FIXED_POINT on
  26. #option FLOATING_ARITHMETIC off
  27. #Floating point:
  28. option FLOATING_POINT on
  29. option FLOATING_ARITHMETIC on
  30. # Basic error handling, IO and user memory support. The latter allows the
  31. # application program to provide its own implementations of 'malloc' and 'free'.
  32. option SETJMP on
  33. option STDIO on
  34. option USER_MEM on
  35. # To read the full set of PNG images correctly interlace, transparency and
  36. # 16-bit support is required. The application can implement interlace itself,
  37. # but very few do and it's no longer possible to disable it when READ is
  38. # enabled.
  39. option READ_tRNS on
  40. option READ_16BIT on
  41. # Everything else is application dependent. This file assumes the app handles
  42. # all the native PNG bit layouts, so it doesn't need any of layout change
  43. # transforms, but needs libpng to perform gamma correction. It doesn't do any
  44. # colorspace stuff and ignores the 'significant bit' information.
  45. #
  46. # If your app always expands the image to a limited set of bit layouts you
  47. # probably want to consider using the simplified API instead of the low level
  48. # one - see png.h and s_read.dfa.
  49. option READ_GAMMA on