opencv/cmake/OpenCVFindLibsGrfmt.cmake

# ----------------------------------------------------------------------------
#  Detect 3rd-party image IO libraries
# ----------------------------------------------------------------------------

# --- zlib (required) ---
if(BUILD_ZLIB)
  ocv_clear_vars(ZLIB_FOUND)
else()
  include(FindZLIB)
  if(ZLIB_FOUND AND ANDROID)
    if(ZLIB_LIBRARY STREQUAL "${ANDROID_SYSROOT}/usr/lib/libz.so")
      set(ZLIB_LIBRARY z)
      set(ZLIB_LIBRARIES z)
    endif()
  endif()
endif()

if(NOT ZLIB_FOUND)
  ocv_clear_vars(ZLIB_LIBRARY ZLIB_LIBRARIES ZLIB_INCLUDE_DIR)

  set(ZLIB_LIBRARY zlib)
  set(ZLIB_LIBRARIES ${ZLIB_LIBRARY})
  add_subdirectory("${OpenCV_SOURCE_DIR}/3rdparty/zlib")
  set(ZLIB_INCLUDE_DIR "${${ZLIB_LIBRARY}_SOURCE_DIR}" "${${ZLIB_LIBRARY}_BINARY_DIR}")

  ocv_parse_header2(ZLIB "${${ZLIB_LIBRARY}_SOURCE_DIR}/zlib.h" ZLIB_VERSION)
endif()

# --- libtiff (optional, should be searched after zlib) ---
if(WITH_TIFF)
  if(BUILD_TIFF)
    ocv_clear_vars(TIFF_FOUND)
  else()
    include(FindTIFF)
    if(TIFF_FOUND)
      ocv_parse_header("${TIFF_INCLUDE_DIR}/tiff.h" TIFF_VERSION_LINES TIFF_VERSION_CLASSIC TIFF_VERSION_BIG TIFF_VERSION TIFF_BIGTIFF_VERSION)
    endif()
  endif()

  if(NOT TIFF_FOUND)
    ocv_clear_vars(TIFF_LIBRARY TIFF_LIBRARIES TIFF_INCLUDE_DIR)

    set(TIFF_LIBRARY libtiff)
    set(TIFF_LIBRARIES ${TIFF_LIBRARY})
    add_subdirectory("${OpenCV_SOURCE_DIR}/3rdparty/libtiff")
    set(TIFF_INCLUDE_DIR "${${TIFF_LIBRARY}_SOURCE_DIR}" "${${TIFF_LIBRARY}_BINARY_DIR}")
    ocv_parse_header("${${TIFF_LIBRARY}_SOURCE_DIR}/tiff.h" TIFF_VERSION_LINES TIFF_VERSION_CLASSIC TIFF_VERSION_BIG TIFF_VERSION TIFF_BIGTIFF_VERSION)
  endif()

  if(TIFF_VERSION_CLASSIC AND NOT TIFF_VERSION)
    set(TIFF_VERSION ${TIFF_VERSION_CLASSIC})
  endif()

  if(TIFF_BIGTIFF_VERSION AND NOT TIFF_VERSION_BIG)
    set(TIFF_VERSION_BIG ${TIFF_BIGTIFF_VERSION})
  endif()

  if(NOT TIFF_VERSION_STRING AND TIFF_INCLUDE_DIR)
    list(GET TIFF_INCLUDE_DIR 0 _TIFF_INCLUDE_DIR)
    if(EXISTS "${_TIFF_INCLUDE_DIR}/tiffvers.h")
      file(STRINGS "${_TIFF_INCLUDE_DIR}/tiffvers.h" tiff_version_str REGEX "^#define[\t ]+TIFFLIB_VERSION_STR[\t ]+\"LIBTIFF, Version .*")
      string(REGEX REPLACE "^#define[\t ]+TIFFLIB_VERSION_STR[\t ]+\"LIBTIFF, Version +([^ \\n]*).*" "\\1" TIFF_VERSION_STRING "${tiff_version_str}")
      unset(tiff_version_str)
    endif()
    unset(_TIFF_INCLUDE_DIR)
  endif()

  set(HAVE_TIFF YES)
endif()

# --- libjpeg (optional) ---
if(WITH_JPEG)
  if(BUILD_JPEG)
    ocv_clear_vars(JPEG_FOUND)
  else()
    include(FindJPEG)
  endif()

  if(NOT JPEG_FOUND)
    ocv_clear_vars(JPEG_LIBRARY JPEG_LIBRARIES JPEG_INCLUDE_DIR)

    set(JPEG_LIBRARY libjpeg)
    set(JPEG_LIBRARIES ${JPEG_LIBRARY})
    add_subdirectory("${OpenCV_SOURCE_DIR}/3rdparty/libjpeg")
    set(JPEG_INCLUDE_DIR "${${JPEG_LIBRARY}_SOURCE_DIR}")
  endif()

  ocv_parse_header("${JPEG_INCLUDE_DIR}/jpeglib.h" JPEG_VERSION_LINES JPEG_LIB_VERSION)
  set(HAVE_JPEG YES)
endif()

# --- libjasper (optional, should be searched after libjpeg) ---
if(WITH_JASPER)
  if(BUILD_JASPER)
    ocv_clear_vars(JASPER_FOUND)
  else()
    include(FindJasper)
  endif()

  if(NOT JASPER_FOUND)
    ocv_clear_vars(JASPER_LIBRARY JASPER_LIBRARIES JASPER_INCLUDE_DIR)

    set(JASPER_LIBRARY libjasper)
    set(JASPER_LIBRARIES ${JASPER_LIBRARY})
    add_subdirectory("${OpenCV_SOURCE_DIR}/3rdparty/libjasper")
    set(JASPER_INCLUDE_DIR "${${JASPER_LIBRARY}_SOURCE_DIR}")
  endif()

  set(HAVE_JASPER YES)

  if(NOT JASPER_VERSION_STRING)
    ocv_parse_header2(JASPER "${JASPER_INCLUDE_DIR}/jasper/jas_config.h" JAS_VERSION "")
  endif()
endif()

# --- libpng (optional, should be searched after zlib) ---
if(WITH_PNG)
  if(BUILD_PNG)
    ocv_clear_vars(PNG_FOUND)
  else()
    include(FindPNG)
    if(PNG_FOUND)
      include(CheckIncludeFile)
      check_include_file("${PNG_PNG_INCLUDE_DIR}/libpng/png.h" HAVE_LIBPNG_PNG_H)
      if(HAVE_LIBPNG_PNG_H)
        ocv_parse_header("${PNG_PNG_INCLUDE_DIR}/libpng/png.h" PNG_VERSION_LINES PNG_LIBPNG_VER_MAJOR PNG_LIBPNG_VER_MINOR PNG_LIBPNG_VER_RELEASE)
      else()
        ocv_parse_header("${PNG_PNG_INCLUDE_DIR}/png.h" PNG_VERSION_LINES PNG_LIBPNG_VER_MAJOR PNG_LIBPNG_VER_MINOR PNG_LIBPNG_VER_RELEASE)
      endif()
    endif()
  endif()

  if(NOT PNG_FOUND)
    ocv_clear_vars(PNG_LIBRARY PNG_LIBRARIES PNG_INCLUDE_DIR PNG_PNG_INCLUDE_DIR HAVE_LIBPNG_PNG_H PNG_DEFINITIONS)

    set(PNG_LIBRARY libpng)
    set(PNG_LIBRARIES ${PNG_LIBRARY})
    add_subdirectory("${OpenCV_SOURCE_DIR}/3rdparty/libpng")
    set(PNG_INCLUDE_DIR "${${PNG_LIBRARY}_SOURCE_DIR}")
    set(PNG_DEFINITIONS "")
    ocv_parse_header("${PNG_INCLUDE_DIR}/png.h" PNG_VERSION_LINES PNG_LIBPNG_VER_MAJOR PNG_LIBPNG_VER_MINOR PNG_LIBPNG_VER_RELEASE)
  endif()

  set(HAVE_PNG YES)
  set(PNG_VERSION "${PNG_LIBPNG_VER_MAJOR}.${PNG_LIBPNG_VER_MINOR}.${PNG_LIBPNG_VER_RELEASE}")
endif()

# --- OpenEXR (optional) ---
if(WITH_OPENEXR)
  if(BUILD_OPENEXR)
    ocv_clear_vars(OPENEXR_FOUND)
  else()
    include("${OpenCV_SOURCE_DIR}/cmake/OpenCVFindOpenEXR.cmake")
  endif()

  if(NOT OPENEXR_FOUND)
    ocv_clear_vars(OPENEXR_INCLUDE_PATHS OPENEXR_LIBRARIES OPENEXR_ILMIMF_LIBRARY OPENEXR_VERSION)

    set(OPENEXR_LIBRARIES IlmImf)
    set(OPENEXR_ILMIMF_LIBRARY IlmImf)
    add_subdirectory("${OpenCV_SOURCE_DIR}/3rdparty/openexr")
  endif()

  set(HAVE_OPENEXR YES)
endif()

#cmake 2.8.2 bug - it fails to determine zlib version
if(ZLIB_FOUND)
  ocv_parse_header2(ZLIB "${ZLIB_INCLUDE_DIR}/zlib.h" ZLIB_VERSION)
endif()

# --- Apple ImageIO ---
if(WITH_IMAGEIO)
  set(HAVE_IMAGEIO YES)
endif()