pngconf.h

一个国人自己实现图像库的程序（有参考价值）

#  define PNG_FIXED_POINT_SUPPORTED
#endif

#ifndef PNG_NO_FREE_ME
#  define PNG_FREE_ME_SUPPORTED
#endif

#if defined(PNG_READ_SUPPORTED)

#if !defined(PNG_READ_TRANSFORMS_NOT_SUPPORTED) && \
      !defined(PNG_NO_READ_TRANSFORMS)
#  define PNG_READ_TRANSFORMS_SUPPORTED
#endif

#ifdef PNG_READ_TRANSFORMS_SUPPORTED
#  ifndef PNG_NO_READ_EXPAND
#    define PNG_READ_EXPAND_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_SHIFT
#    define PNG_READ_SHIFT_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_PACK
#    define PNG_READ_PACK_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_BGR
#    define PNG_READ_BGR_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_SWAP
#    define PNG_READ_SWAP_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_PACKSWAP
#    define PNG_READ_PACKSWAP_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_INVERT
#    define PNG_READ_INVERT_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_DITHER
#    define PNG_READ_DITHER_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_BACKGROUND
#    define PNG_READ_BACKGROUND_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_16_TO_8
#    define PNG_READ_16_TO_8_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_FILLER
#    define PNG_READ_FILLER_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_GAMMA
#    define PNG_READ_GAMMA_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_GRAY_TO_RGB
#    define PNG_READ_GRAY_TO_RGB_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_SWAP_ALPHA
#    define PNG_READ_SWAP_ALPHA_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_INVERT_ALPHA
#    define PNG_READ_INVERT_ALPHA_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_STRIP_ALPHA
#    define PNG_READ_STRIP_ALPHA_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_USER_TRANSFORM
#    define PNG_READ_USER_TRANSFORM_SUPPORTED
#  endif
#  ifndef PNG_NO_READ_RGB_TO_GRAY
#    define PNG_READ_RGB_TO_GRAY_SUPPORTED
#  endif
#endif /* PNG_READ_TRANSFORMS_SUPPORTED */

#if !defined(PNG_NO_PROGRESSIVE_READ) && \
 !defined(PNG_PROGRESSIVE_READ_NOT_SUPPORTED)  /* if you don't do progressive */
#  define PNG_PROGRESSIVE_READ_SUPPORTED     /* reading.  This is not talking */
#endif                               /* about interlacing capability!  You'll */
              /* still have interlacing unless you change the following line: */

#define PNG_READ_INTERLACING_SUPPORTED /* required for PNG-compliant decoders */

#ifndef PNG_NO_READ_COMPOSITE_NODIV
#  ifndef PNG_NO_READ_COMPOSITED_NODIV  /* libpng-1.0.x misspelling */
#    define PNG_READ_COMPOSITE_NODIV_SUPPORTED   /* well tested on Intel, SGI */
#  endif
#endif

/* Deprecated, will be removed from version 2.0.0.
   Use PNG_MNG_FEATURES_SUPPORTED instead. */
#ifndef PNG_NO_READ_EMPTY_PLTE
#  define PNG_READ_EMPTY_PLTE_SUPPORTED
#endif

#endif /* PNG_READ_SUPPORTED */

#if defined(PNG_WRITE_SUPPORTED)

# if !defined(PNG_WRITE_TRANSFORMS_NOT_SUPPORTED) && \
    !defined(PNG_NO_WRITE_TRANSFORMS)
#  define PNG_WRITE_TRANSFORMS_SUPPORTED
#endif

#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
#  ifndef PNG_NO_WRITE_SHIFT
#    define PNG_WRITE_SHIFT_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_PACK
#    define PNG_WRITE_PACK_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_BGR
#    define PNG_WRITE_BGR_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_SWAP
#    define PNG_WRITE_SWAP_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_PACKSWAP
#    define PNG_WRITE_PACKSWAP_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_INVERT
#    define PNG_WRITE_INVERT_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_FILLER
#    define PNG_WRITE_FILLER_SUPPORTED   /* same as WRITE_STRIP_ALPHA */
#  endif
#  ifndef PNG_NO_WRITE_SWAP_ALPHA
#    define PNG_WRITE_SWAP_ALPHA_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_INVERT_ALPHA
#    define PNG_WRITE_INVERT_ALPHA_SUPPORTED
#  endif
#  ifndef PNG_NO_WRITE_USER_TRANSFORM
#    define PNG_WRITE_USER_TRANSFORM_SUPPORTED
#  endif
#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */

#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
#  ifndef PNG_NO_USER_TRANSFORM_PTR
#    define PNG_USER_TRANSFORM_PTR_SUPPORTED
#  endif
#endif

#define PNG_WRITE_INTERLACING_SUPPORTED  /* not required for PNG-compliant
                                            encoders, but can cause trouble
                                            if left undefined */

#if !defined(PNG_NO_WRITE_WEIGHTED_FILTER) && \
     defined(PNG_FLOATING_POINT_SUPPORTED)
#  define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
#endif

#ifndef PNG_NO_ERROR_NUMBERS
#define PNG_ERROR_NUMBERS_SUPPORTED
#endif

#ifndef PNG_NO_WRITE_FLUSH
#  define PNG_WRITE_FLUSH_SUPPORTED
#endif

/* Deprecated, see PNG_MNG_FEATURES_SUPPORTED, above */
#ifndef PNG_NO_WRITE_EMPTY_PLTE
#  define PNG_WRITE_EMPTY_PLTE_SUPPORTED
#endif

#endif /* PNG_WRITE_SUPPORTED */

#ifndef PNG_NO_STDIO
#  define PNG_TIME_RFC1123_SUPPORTED
#endif

/* This adds extra functions in pngget.c for accessing data from the
 * info pointer (added in version 0.99)
 * png_get_image_width()
 * png_get_image_height()
 * png_get_bit_depth()
 * png_get_color_type()
 * png_get_compression_type()
 * png_get_filter_type()
 * png_get_interlace_type()
 * png_get_pixel_aspect_ratio()
 * png_get_pixels_per_meter()
 * png_get_x_offset_pixels()
 * png_get_y_offset_pixels()
 * png_get_x_offset_microns()
 * png_get_y_offset_microns()
 */
#if !defined(PNG_NO_EASY_ACCESS) && !defined(PNG_EASY_ACCESS_SUPPORTED)
#  define PNG_EASY_ACCESS_SUPPORTED
#endif

/* PNG_ASSEMBLER_CODE was enabled by default in version 1.2.0 
   even when PNG_USE_PNGVCRD or PNG_USE_PNGGCCRD is not defined */
#if defined(PNG_READ_SUPPORTED) && !defined(PNG_NO_ASSEMBLER_CODE)
#  ifndef PNG_ASSEMBLER_CODE_SUPPORTED
#    define PNG_ASSEMBLER_CODE_SUPPORTED
#  endif
#  if !defined(PNG_MMX_CODE_SUPPORTED) && !defined(PNG_NO_MMX_CODE)
#    define PNG_MMX_CODE_SUPPORTED
#  endif
#endif

/* If you are sure that you don't need thread safety and you are compiling
   with PNG_USE_PNGCCRD for an MMX application, you can define this for
   faster execution.  See pnggccrd.c.
#define PNG_THREAD_UNSAFE_OK
*/

#if !defined(PNG_NO_USER_MEM) && !defined(PNG_USER_MEM_SUPPORTED)
#  define PNG_USER_MEM_SUPPORTED
#endif

/* These are currently experimental features, define them if you want */

/* very little testing */
/*
#ifdef PNG_READ_SUPPORTED
#  ifndef PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
#    define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
#  endif
#endif
*/

/* This is only for PowerPC big-endian and 680x0 systems */
/* some testing */
/*
#ifdef PNG_READ_SUPPORTED
#  ifndef PNG_PNG_READ_BIG_ENDIAN_SUPPORTED
#    define PNG_READ_BIG_ENDIAN_SUPPORTED
#  endif
#endif
*/

/* Buggy compilers (e.g., gcc 2.7.2.2) need this */
/*
#define PNG_NO_POINTER_INDEXING
*/

/* These functions are turned off by default, as they will be phased out. */
/*
#define  PNG_USELESS_TESTS_SUPPORTED
#define  PNG_CORRECT_PALETTE_SUPPORTED
*/

/* Any chunks you are not interested in, you can undef here.  The
 * ones that allocate memory may be expecially important (hIST,
 * tEXt, zTXt, tRNS, pCAL).  Others will just save time and make png_info
 * a bit smaller.
 */

#if defined(PNG_READ_SUPPORTED) && \
    !defined(PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
    !defined(PNG_NO_READ_ANCILLARY_CHUNKS)
#  define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
#endif

#if defined(PNG_WRITE_SUPPORTED) && \
    !defined(PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
    !defined(PNG_NO_WRITE_ANCILLARY_CHUNKS)
#  define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
#endif

#ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED

#ifdef PNG_NO_READ_TEXT
#  define PNG_NO_READ_iTXt
#  define PNG_NO_READ_tEXt
#  define PNG_NO_READ_zTXt
#endif
#ifndef PNG_NO_READ_bKGD
#  define PNG_READ_bKGD_SUPPORTED
#  define PNG_bKGD_SUPPORTED
#endif
#ifndef PNG_NO_READ_cHRM
#  define PNG_READ_cHRM_SUPPORTED
#  define PNG_cHRM_SUPPORTED
#endif
#ifndef PNG_NO_READ_gAMA
#  define PNG_READ_gAMA_SUPPORTED
#  define PNG_gAMA_SUPPORTED
#endif
#ifndef PNG_NO_READ_hIST
#  define PNG_READ_hIST_SUPPORTED
#  define PNG_hIST_SUPPORTED
#endif
#ifndef PNG_NO_READ_iCCP
#  define PNG_READ_iCCP_SUPPORTED
#  define PNG_iCCP_SUPPORTED
#endif
#ifndef PNG_NO_READ_iTXt
#  ifndef PNG_READ_iTXt_SUPPORTED
#    define PNG_READ_iTXt_SUPPORTED
#  endif
#  ifndef PNG_iTXt_SUPPORTED
#    define PNG_iTXt_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_READ_oFFs
#  define PNG_READ_oFFs_SUPPORTED
#  define PNG_oFFs_SUPPORTED
#endif
#ifndef PNG_NO_READ_pCAL
#  define PNG_READ_pCAL_SUPPORTED
#  define PNG_pCAL_SUPPORTED
#endif
#ifndef PNG_NO_READ_sCAL
#  define PNG_READ_sCAL_SUPPORTED
#  define PNG_sCAL_SUPPORTED
#endif
#ifndef PNG_NO_READ_pHYs
#  define PNG_READ_pHYs_SUPPORTED
#  define PNG_pHYs_SUPPORTED
#endif
#ifndef PNG_NO_READ_sBIT
#  define PNG_READ_sBIT_SUPPORTED
#  define PNG_sBIT_SUPPORTED
#endif
#ifndef PNG_NO_READ_sPLT
#  define PNG_READ_sPLT_SUPPORTED
#  define PNG_sPLT_SUPPORTED
#endif
#ifndef PNG_NO_READ_sRGB
#  define PNG_READ_sRGB_SUPPORTED
#  define PNG_sRGB_SUPPORTED
#endif
#ifndef PNG_NO_READ_tEXt
#  define PNG_READ_tEXt_SUPPORTED
#  define PNG_tEXt_SUPPORTED
#endif
#ifndef PNG_NO_READ_tIME
#  define PNG_READ_tIME_SUPPORTED
#  define PNG_tIME_SUPPORTED
#endif
#ifndef PNG_NO_READ_tRNS
#  define PNG_READ_tRNS_SUPPORTED
#  define PNG_tRNS_SUPPORTED
#endif
#ifndef PNG_NO_READ_zTXt
#  define PNG_READ_zTXt_SUPPORTED
#  define PNG_zTXt_SUPPORTED
#endif
#ifndef PNG_NO_READ_UNKNOWN_CHUNKS
#  define PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
#  ifndef PNG_UNKNOWN_CHUNKS_SUPPORTED
#    define PNG_UNKNOWN_CHUNKS_SUPPORTED
#  endif
#  ifndef PNG_NO_HANDLE_AS_UNKNOWN
#    define PNG_HANDLE_AS_UNKNOWN_SUPPORTED
#  endif
#endif
#if !defined(PNG_NO_READ_USER_CHUNKS) && \
     defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)
#  define PNG_READ_USER_CHUNKS_SUPPORTED
#  define PNG_USER_CHUNKS_SUPPORTED
#  ifdef PNG_NO_READ_UNKNOWN_CHUNKS
#    undef PNG_NO_READ_UNKNOWN_CHUNKS
#  endif
#  ifdef PNG_NO_HANDLE_AS_UNKNOWN
#    undef PNG_NO_HANDLE_AS_UNKNOWN
#  endif
#endif
#ifndef PNG_NO_READ_OPT_PLTE
#  define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the */
#endif                      /* optional PLTE chunk in RGB and RGBA images */
#if defined(PNG_READ_iTXt_SUPPORTED) || defined(PNG_READ_tEXt_SUPPORTED) || \
    defined(PNG_READ_zTXt_SUPPORTED)
#  define PNG_READ_TEXT_SUPPORTED
#  define PNG_TEXT_SUPPORTED
#endif

#endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */

#ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED

#ifdef PNG_NO_WRITE_TEXT
#  define PNG_NO_WRITE_iTXt
#  define PNG_NO_WRITE_tEXt
#  define PNG_NO_WRITE_zTXt
#endif
#ifndef PNG_NO_WRITE_bKGD
#  define PNG_WRITE_bKGD_SUPPORTED
#  ifndef PNG_bKGD_SUPPORTED
#    define PNG_bKGD_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_cHRM
#  define PNG_WRITE_cHRM_SUPPORTED
#  ifndef PNG_cHRM_SUPPORTED
#    define PNG_cHRM_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_gAMA
#  define PNG_WRITE_gAMA_SUPPORTED
#  ifndef PNG_gAMA_SUPPORTED
#    define PNG_gAMA_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_hIST
#  define PNG_WRITE_hIST_SUPPORTED
#  ifndef PNG_hIST_SUPPORTED
#    define PNG_hIST_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_iCCP
#  define PNG_WRITE_iCCP_SUPPORTED
#  ifndef PNG_iCCP_SUPPORTED
#    define PNG_iCCP_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_iTXt
#  ifndef PNG_WRITE_iTXt_SUPPORTED
#    define PNG_WRITE_iTXt_SUPPORTED
#  endif
#  ifndef PNG_iTXt_SUPPORTED
#    define PNG_iTXt_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_oFFs
#  define PNG_WRITE_oFFs_SUPPORTED
#  ifndef PNG_oFFs_SUPPORTED
#    define PNG_oFFs_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_pCAL
#  define PNG_WRITE_pCAL_SUPPORTED
#  ifndef PNG_pCAL_SUPPORTED
#    define PNG_pCAL_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_sCAL
#  define PNG_WRITE_sCAL_SUPPORTED
#  ifndef PNG_sCAL_SUPPORTED
#    define PNG_sCAL_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_pHYs
#  define PNG_WRITE_pHYs_SUPPORTED
#  ifndef PNG_pHYs_SUPPORTED
#    define PNG_pHYs_SUPPORTED
#  endif
#endif
#ifndef PNG_NO_WRITE_sBIT
#  define PNG_WRITE_sBIT_SUPPORTED
#  ifndef PNG_sBIT_SUPPORTED
#    define PNG_sBIT_SUPPORTED
#  endif
#endif