DOKK / manpages / debian 12 / libimage-png-libpng-perl / Image::PNG::Const.3pm.en
Image::PNG::Const(3pm) User Contributed Perl Documentation Image::PNG::Const(3pm)

Image::PNG::Const - Constants for libpng

    # Get just the constants you need:
    use Image::PNG::Const qw/PNG_TRANSFORM_INVERT_ALPHA
                             PNG_COLOR_MASK_ALPHA/;
    # Get everything:
    use Image::PNG::Const ':all';

This module is a helper for Image::PNG::Libpng. It contains no functions, only constants.

This file contains the following constants, from the header file of the PNG library, "png.h":

PNG_AFTER_IDAT has value 0x08.
PNG_ALL_FILTERS has value ((0x08 | 0x10 | 0x20) | 0x40 | 0x80).
PNG_ALL_MNG_FEATURES has value 0x05.
PNG_ALPHA_ASSOCIATED has value 1.
PNG_ALPHA_BROKEN has value 3.
PNG_ALPHA_OPTIMIZED has value 2.
PNG_ALPHA_PNG has value 0.
PNG_ALPHA_PREMULTIPLIED has value 1.
PNG_ALPHA_STANDARD has value 1.
PNG_ARM_NEON has value 0.
PNG_BACKGROUND_GAMMA_FILE has value 2.
PNG_BACKGROUND_GAMMA_SCREEN has value 1.
PNG_BACKGROUND_GAMMA_UNIQUE has value 3.
PNG_BACKGROUND_GAMMA_UNKNOWN has value 0.
PNG_BLEND_OP_OVER has value 0x01.
PNG_BLEND_OP_SOURCE has value 0x00.
PNG_COLOR_MASK_ALPHA has value 4.
PNG_COLOR_MASK_COLOR has value 2.
PNG_COLOR_MASK_PALETTE has value 1.
PNG_COLOR_TYPE_GA has value (4).
PNG_COLOR_TYPE_GRAY has value 0.
PNG_COLOR_TYPE_GRAY_ALPHA has value (4).
PNG_COLOR_TYPE_PALETTE has value (2 | 1).
PNG_COLOR_TYPE_RGB has value (2).
PNG_COLOR_TYPE_RGBA has value (2 | 4).
PNG_COLOR_TYPE_RGB_ALPHA has value (2 | 4).
PNG_COMPRESSION_TYPE_BASE has value 0.
PNG_COMPRESSION_TYPE_DEFAULT has value 0.
PNG_CRC_DEFAULT has value 0.
PNG_CRC_ERROR_QUIT has value 1.
PNG_CRC_NO_CHANGE has value 5.
PNG_CRC_QUIET_USE has value 4.
PNG_CRC_WARN_DISCARD has value 2.
PNG_CRC_WARN_USE has value 3.
PNG_DEFAULT_sRGB has value -1.
PNG_DISPOSE_OP_BACKGROUND has value 0x01.
PNG_DISPOSE_OP_NONE has value 0x00.
PNG_DISPOSE_OP_PREVIOUS has value 0x02.
PNG_EQUATION_ARBITRARY has value 2.
PNG_EQUATION_BASE_E has value 1.
PNG_EQUATION_HYPERBOLIC has value 3.
PNG_EQUATION_LINEAR has value 0.
PNG_ERROR_ACTION_ERROR has value 3.
PNG_ERROR_ACTION_NONE has value 1.
PNG_ERROR_ACTION_WARN has value 2.
PNG_FAST_FILTERS has value (0x08 | 0x10 | 0x20).
PNG_FILLER_AFTER has value 1.
PNG_FILLER_BEFORE has value 0.
PNG_FILTER_AVG has value 0x40.
PNG_FILTER_HEURISTIC_DEFAULT has value 0.
PNG_FILTER_HEURISTIC_UNWEIGHTED has value 1.
PNG_FILTER_HEURISTIC_WEIGHTED has value 2.
PNG_FILTER_NONE has value 0x08.
PNG_FILTER_PAETH has value 0x80.
PNG_FILTER_SUB has value 0x10.
PNG_FILTER_TYPE_BASE has value 0.
PNG_FILTER_TYPE_DEFAULT has value 0.
PNG_FILTER_UP has value 0x20.
PNG_FILTER_VALUE_AVG has value 3.
PNG_FILTER_VALUE_NONE has value 0.
PNG_FILTER_VALUE_PAETH has value 4.
PNG_FILTER_VALUE_SUB has value 1.
PNG_FILTER_VALUE_UP has value 2.
PNG_FLAG_MNG_EMPTY_PLTE has value 0x01.
PNG_FLAG_MNG_FILTER_64 has value 0x04.
PNG_FORMAT_ABGR has value (((0x02|0x10)|0x01)|0x20).
PNG_FORMAT_ABGR_COLORMAP has value ((((0x02|0x10)|0x01)|0x20)|0x08).
PNG_FORMAT_AG has value (0x01|0x20).
PNG_FORMAT_ARGB has value ((0x02|0x01)|0x20).
PNG_FORMAT_ARGB_COLORMAP has value (((0x02|0x01)|0x20)|0x08).
PNG_FORMAT_BGR has value (0x02|0x10).
PNG_FORMAT_BGRA has value ((0x02|0x10)|0x01).
PNG_FORMAT_BGRA_COLORMAP has value (((0x02|0x10)|0x01)|0x08).
PNG_FORMAT_BGR_COLORMAP has value ((0x02|0x10)|0x08).
PNG_FORMAT_FLAG_AFIRST has value 0x20.
PNG_FORMAT_FLAG_ALPHA has value 0x01.
PNG_FORMAT_FLAG_ASSOCIATED_ALPHA has value 0x40.
PNG_FORMAT_FLAG_BGR has value 0x10.
PNG_FORMAT_FLAG_COLOR has value 0x02.
PNG_FORMAT_FLAG_COLORMAP has value 0x08.
PNG_FORMAT_FLAG_LINEAR has value 0x04.
PNG_FORMAT_GA has value 0x01.
PNG_FORMAT_GRAY has value 0.
PNG_FORMAT_LINEAR_RGB has value (0x04|0x02).
PNG_FORMAT_LINEAR_Y has value 0x04.
PNG_FORMAT_LINEAR_Y_ALPHA has value (0x04|0x01).
PNG_FORMAT_RGB has value 0x02.
PNG_FORMAT_RGBA has value (0x02|0x01).
PNG_FORMAT_RGBA_COLORMAP has value ((0x02|0x01)|0x08).
PNG_FORMAT_RGB_COLORMAP has value (0x02|0x08).
PNG_FP_1 has value 100000.
PNG_FP_HALF has value 50000.
PNG_FP_MIN has value (-PNG_FP_MAX).
PNG_FREE_ALL has value 0xffff.
PNG_FREE_EXIF has value 0x8000.
PNG_FREE_HIST has value 0x0008.
PNG_FREE_ICCP has value 0x0010.
PNG_FREE_MUL has value 0x4220.
PNG_FREE_PCAL has value 0x0080.
PNG_FREE_PLTE has value 0x1000.
PNG_FREE_ROWS has value 0x0040.
PNG_FREE_SCAL has value 0x0100.
PNG_FREE_SPLT has value 0x0020.
PNG_FREE_TEXT has value 0x4000.
PNG_FREE_TRNS has value 0x2000.
PNG_FREE_UNKN has value 0x0200.
PNG_GAMMA_LINEAR has value 100000.
PNG_GAMMA_MAC_18 has value -2.
PNG_GAMMA_THRESHOLD has value (PNG_GAMMA_THRESHOLD_FIXED*.00001).
PNG_GAMMA_sRGB has value 220000.
PNG_HANDLE_CHUNK_ALWAYS has value 3.
PNG_HANDLE_CHUNK_AS_DEFAULT has value 0.
PNG_HANDLE_CHUNK_IF_SAFE has value 2.
PNG_HANDLE_CHUNK_NEVER has value 1.
PNG_HAVE_IHDR has value 0x01.
PNG_HAVE_PLTE has value 0x02.
PNG_IGNORE_ADLER32 has value 8.
PNG_IMAGE_ERROR has value 2.
PNG_IMAGE_FLAG_16BIT_sRGB has value 0x04.
PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB has value 0x01.
PNG_IMAGE_FLAG_FAST has value 0x02.
PNG_IMAGE_VERSION has value 1.
PNG_IMAGE_WARNING has value 1.
PNG_INFO_IDAT has value 0x8000.
PNG_INFO_PLTE has value 0x0008.
PNG_INFO_acTL has value 0x20000.
PNG_INFO_bKGD has value 0x0020.
PNG_INFO_cHRM has value 0x0004.
PNG_INFO_eXIf has value 0x10000.
PNG_INFO_fcTL has value 0x40000.
PNG_INFO_gAMA has value 0x0001.
PNG_INFO_hIST has value 0x0040.
PNG_INFO_iCCP has value 0x1000.
PNG_INFO_oFFs has value 0x0100.
PNG_INFO_pCAL has value 0x0400.
PNG_INFO_pHYs has value 0x0080.
PNG_INFO_sBIT has value 0x0002.
PNG_INFO_sCAL has value 0x4000.
PNG_INFO_sPLT has value 0x2000.
PNG_INFO_sRGB has value 0x0800.
PNG_INFO_tIME has value 0x0200.
PNG_INFO_tRNS has value 0x0010.
PNG_INTERLACE_ADAM7 has value 1.
PNG_INTERLACE_ADAM7_PASSES has value 7.
PNG_INTERLACE_NONE has value 0.
PNG_INTRAPIXEL_DIFFERENCING has value 64.
PNG_IO_CHUNK_CRC has value 0x0080.
PNG_IO_CHUNK_DATA has value 0x0040.
PNG_IO_CHUNK_HDR has value 0x0020.
PNG_IO_MASK_LOC has value 0x00f0.
PNG_IO_MASK_OP has value 0x000f.
PNG_IO_NONE has value 0x0000.
PNG_IO_READING has value 0x0001.
PNG_IO_SIGNATURE has value 0x0010.
PNG_IO_WRITING has value 0x0002.
PNG_ITXT_COMPRESSION_NONE has value 1.
PNG_ITXT_COMPRESSION_zTXt has value 2.
PNG_KEYWORD_MAX_LENGTH has value 79.
PNG_MAXIMUM_INFLATE_WINDOW has value 2.
PNG_MAX_PALETTE_LENGTH has value 256.
PNG_MIPS_MSA has value 6.
PNG_NO_FILTERS has value 0x00.
PNG_OFFSET_MICROMETER has value 1.
PNG_OFFSET_PIXEL has value 0.
PNG_OPTION_INVALID has value 1.
PNG_OPTION_NEXT has value 12.
PNG_OPTION_OFF has value 2.
PNG_OPTION_ON has value 3.
PNG_OPTION_UNSET has value 0.
PNG_POWERPC_VSX has value 10.
PNG_RESOLUTION_METER has value 1.
PNG_RESOLUTION_UNKNOWN has value 0.
PNG_RGB_TO_GRAY_DEFAULT has value (-1).
PNG_SCALE_METER has value 1.
PNG_SCALE_RADIAN has value 2.
PNG_SCALE_UNKNOWN has value 0.
PNG_SKIP_sRGB_CHECK_PROFILE has value 4.
PNG_TEXT_COMPRESSION_NONE has value -1.
PNG_TEXT_COMPRESSION_NONE_WR has value -3.
PNG_TEXT_COMPRESSION_zTXt has value 0.
PNG_TEXT_COMPRESSION_zTXt_WR has value -2.
PNG_TRANSFORM_BGR has value 0x0080.
PNG_TRANSFORM_EXPAND has value 0x0010.
PNG_TRANSFORM_EXPAND_16 has value 0x4000.
PNG_TRANSFORM_GRAY_TO_RGB has value 0x2000.
PNG_TRANSFORM_IDENTITY has value 0x0000.
PNG_TRANSFORM_INVERT_ALPHA has value 0x0400.
PNG_TRANSFORM_INVERT_MONO has value 0x0020.
PNG_TRANSFORM_PACKING has value 0x0004.
PNG_TRANSFORM_PACKSWAP has value 0x0008.
PNG_TRANSFORM_SCALE_16 has value 0x8000.
PNG_TRANSFORM_SHIFT has value 0x0040.
PNG_TRANSFORM_STRIP_16 has value 0x0001.
PNG_TRANSFORM_STRIP_ALPHA has value 0x0002.
PNG_TRANSFORM_STRIP_FILLER has value 0x0800.
PNG_TRANSFORM_STRIP_FILLER_AFTER has value 0x1000.
PNG_TRANSFORM_STRIP_FILLER_BEFORE has value 0x0800.
PNG_TRANSFORM_SWAP_ALPHA has value 0x0100.
PNG_TRANSFORM_SWAP_ENDIAN has value 0x0200.
PNG_sRGB_INTENT_ABSOLUTE has value 3.
PNG_sRGB_INTENT_PERCEPTUAL has value 0.
PNG_sRGB_INTENT_RELATIVE has value 1.
PNG_sRGB_INTENT_SATURATION has value 2.

Nothing is exported by default, but all the symbols in this module can be exported on request. There is one export tag, 'all', which exports all the symbols in this module:

    use Image::PNG::Const ':all';

This Perl module was generated from the file png.h supplied with version 1.6.37 of libpng.

Ben Bullock, <bkb@cpan.org>

This package and associated files are copyright (C) 2011-2021 Ben Bullock.

You can use, copy, modify and redistribute this package and associated files under the Perl Artistic Licence or the GNU General Public Licence.

2022-10-19 perl v5.36.0