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/*M///////////////////////////////////////////////////////////////////////////////////////
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//
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//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
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//
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//  By downloading, copying, installing or using the software you agree to this license.
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//  If you do not agree to this license, do not download, install,
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//  copy or use the software.
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//
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//
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//                          License Agreement
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//                For Open Source Computer Vision Library
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//
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// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
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// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
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// Third party copyrights are property of their respective owners.
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//
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// Redistribution and use in source and binary forms, with or without modification,
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// are permitted provided that the following conditions are met:
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//
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//   * Redistribution's of source code must retain the above copyright notice,
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//     this list of conditions and the following disclaimer.
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//
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//   * Redistribution's in binary form must reproduce the above copyright notice,
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//     this list of conditions and the following disclaimer in the documentation
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//     and/or other materials provided with the distribution.
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//   * The name of the copyright holders may not be used to endorse or promote products
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// This software is provided by the copyright holders and contributors "as is" and
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// loss of use, data, or profits; or business interruption) however caused
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// or tort (including negligence or otherwise) arising in any way out of
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// the use of this software, even if advised of the possibility of such damage.
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//
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//M*/
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#ifndef OPENCV_IMGCODECS_HPP
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#define OPENCV_IMGCODECS_HPP
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#include "opencv2/core.hpp"
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/**
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  @defgroup imgcodecs Image file reading and writing
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  @{
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    @defgroup imgcodecs_flags Flags used for image file reading and writing
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    @defgroup imgcodecs_ios iOS glue
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    @defgroup imgcodecs_macosx MacOS(OSX) glue
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  @}
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*/
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//////////////////////////////// image codec ////////////////////////////////
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namespace cv
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{
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//! @addtogroup imgcodecs
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//! @{
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//! @addtogroup imgcodecs_flags
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//! @{
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//! Imread flags
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//! @note IMREAD_COLOR_BGR (IMREAD_COLOR) and IMREAD_COLOR_RGB can not be set at the same time.
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enum ImreadModes {
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       IMREAD_UNCHANGED            = -1, //!< If set, return the loaded image as is (with alpha channel, otherwise it gets cropped). Ignore EXIF orientation.
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       IMREAD_GRAYSCALE            = 0,  //!< If set, always convert image to the single channel grayscale image (codec internal conversion).
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       IMREAD_COLOR_BGR            = 1,  //!< If set, always convert image to the 3 channel BGR color image.
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       IMREAD_COLOR                = 1,  //!< Same as IMREAD_COLOR_BGR.
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       IMREAD_ANYDEPTH             = 2,  //!< If set, return 16-bit/32-bit image when the input has the corresponding depth, otherwise convert it to 8-bit.
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       IMREAD_ANYCOLOR             = 4,  //!< If set, the image is read in any possible color format.
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       IMREAD_LOAD_GDAL            = 8,  //!< If set, use the gdal driver for loading the image.
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       IMREAD_REDUCED_GRAYSCALE_2  = 16, //!< If set, always convert image to the single channel grayscale image and the image size reduced 1/2.
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       IMREAD_REDUCED_COLOR_2      = 17, //!< If set, always convert image to the 3 channel BGR color image and the image size reduced 1/2.
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       IMREAD_REDUCED_GRAYSCALE_4  = 32, //!< If set, always convert image to the single channel grayscale image and the image size reduced 1/4.
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       IMREAD_REDUCED_COLOR_4      = 33, //!< If set, always convert image to the 3 channel BGR color image and the image size reduced 1/4.
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       IMREAD_REDUCED_GRAYSCALE_8  = 64, //!< If set, always convert image to the single channel grayscale image and the image size reduced 1/8.
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       IMREAD_REDUCED_COLOR_8      = 65, //!< If set, always convert image to the 3 channel BGR color image and the image size reduced 1/8.
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       IMREAD_IGNORE_ORIENTATION   = 128, //!< If set, do not rotate the image according to EXIF's orientation flag.
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       IMREAD_COLOR_RGB            = 256, //!< If set, always convert image to the 3 channel RGB color image.
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     };
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//! Imwrite flags
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enum ImwriteFlags {
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       IMWRITE_JPEG_QUALITY        = 1,  //!< For JPEG, it can be a quality from 0 to 100 (the higher is the better). Default value is 95.
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       IMWRITE_JPEG_PROGRESSIVE    = 2,  //!< Enable JPEG features, 0 or 1, default is False.
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       IMWRITE_JPEG_OPTIMIZE       = 3,  //!< Enable JPEG features, 0 or 1, default is False.
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       IMWRITE_JPEG_RST_INTERVAL   = 4,  //!< JPEG restart interval, 0 - 65535, default is 0 - no restart.
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       IMWRITE_JPEG_LUMA_QUALITY   = 5,  //!< Separate luma quality level, 0 - 100, default is -1 - don't use. If JPEG_LIB_VERSION < 70, Not supported.
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       IMWRITE_JPEG_CHROMA_QUALITY = 6,  //!< Separate chroma quality level, 0 - 100, default is -1 - don't use. If JPEG_LIB_VERSION < 70, Not supported.
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       IMWRITE_JPEG_SAMPLING_FACTOR = 7, //!< For JPEG, set sampling factor. See cv::ImwriteJPEGSamplingFactorParams.
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       IMWRITE_PNG_COMPRESSION     = 16, //!< For PNG, it can be the compression level from 0 to 9. A higher value means a smaller size and longer compression time. If specified, strategy is changed to IMWRITE_PNG_STRATEGY_DEFAULT (Z_DEFAULT_STRATEGY). Default value is 1 (best speed setting).
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       IMWRITE_PNG_STRATEGY        = 17, //!< For PNG, One of cv::ImwritePNGFlags, default is IMWRITE_PNG_STRATEGY_RLE.
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       IMWRITE_PNG_BILEVEL         = 18, //!< For PNG, Binary level PNG, 0 or 1, default is 0. For APNG, it is not supported.
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       IMWRITE_PNG_FILTER          = 19, //!< For PNG, One of cv::ImwritePNGFilterFlags, default is IMWRITE_PNG_FILTER_SUB. For APNG, it is not supported.
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       IMWRITE_PNG_ZLIBBUFFER_SIZE = 20, //!< For PNG with libpng, sets the size of the internal zlib compression buffer in bytes, from 6 to 1048576(1024 KiB). Default is 8192(8 KiB). For normal use, 131072(128 KiB) or 262144(256 KiB) may be sufficient. If WITH_SPNG=ON, it is not supported. For APNG, it is not supported.
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       IMWRITE_PXM_BINARY          = 32, //!< For PPM, PGM, or PBM, it can be a binary format flag, 0 or 1. Default value is 1.
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       IMWRITE_EXR_TYPE            = (3 << 4) + 0 /* 48 */, //!< override EXR storage type (FLOAT (FP32) is default)
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       IMWRITE_EXR_COMPRESSION     = (3 << 4) + 1 /* 49 */, //!< override EXR compression type (ZIP_COMPRESSION = 3 is default)
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       IMWRITE_EXR_DWA_COMPRESSION_LEVEL = (3 << 4) + 2 /* 50 */, //!< override EXR DWA compression level (45 is default)
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       IMWRITE_WEBP_QUALITY        = 64, //!< For WEBP, it can be a quality from 1 to 100 (the higher is the better). By default (without any parameter) and for quality above 100 the lossless compression is used.
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       IMWRITE_HDR_COMPRESSION     = (5 << 4) + 0 /* 80 */, //!< specify HDR compression
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       IMWRITE_PAM_TUPLETYPE       = 128,//!< For PAM, sets the TUPLETYPE field to the corresponding string value that is defined for the format
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       IMWRITE_TIFF_RESUNIT        = 256,//!< For TIFF, use to specify which DPI resolution unit to set. See ImwriteTiffResolutionUnitFlags. Default is IMWRITE_TIFF_RESOLUTION_UNIT_INCH.
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       IMWRITE_TIFF_XDPI           = 257,//!< For TIFF, use to specify the X direction DPI
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       IMWRITE_TIFF_YDPI           = 258,//!< For TIFF, use to specify the Y direction DPI
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       IMWRITE_TIFF_COMPRESSION    = 259,//!< For TIFF, use to specify the image compression scheme. See cv::ImwriteTiffCompressionFlags. Note, for images whose depth is CV_32F, only libtiff's SGILOG compression scheme is used. For other supported depths, the compression scheme can be specified by this flag; LZW compression is the default.
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       IMWRITE_TIFF_ROWSPERSTRIP   = 278,//!< For TIFF, use to specify the number of rows per strip.
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       IMWRITE_TIFF_PREDICTOR      = 317,//!< For TIFF, use to specify predictor. See cv::ImwriteTiffPredictorFlags. Default is IMWRITE_TIFF_PREDICTOR_HORIZONTAL .
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       IMWRITE_JPEG2000_COMPRESSION_X1000 = 272,//!< For JPEG2000, use to specify the target compression rate (multiplied by 1000). The value can be from 0 to 1000. Default is 1000.
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       IMWRITE_AVIF_QUALITY        = 512,//!< For AVIF, it can be a quality between 0 and 100 (the higher the better). Default is 95.
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       IMWRITE_AVIF_DEPTH          = 513,//!< For AVIF, it can be 8, 10 or 12. If >8, it is stored/read as CV_32F. Default is 8.
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       IMWRITE_AVIF_SPEED          = 514,//!< For AVIF, it is between 0 (slowest) and 10(fastest). Default is 9.
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       IMWRITE_JPEGXL_QUALITY      = 640,//!< For JPEG XL, it can be a quality from 0 to 100 (the higher is the better). Default value is 95. If set, distance parameter is re-calicurated from quality level automatically. This parameter request libjxl v0.10 or later.
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       IMWRITE_JPEGXL_EFFORT       = 641,//!< For JPEG XL, encoder effort/speed level without affecting decoding speed; it is between 1 (fastest) and 10 (slowest). Default is 7.
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       IMWRITE_JPEGXL_DISTANCE     = 642,//!< For JPEG XL, distance level for lossy compression: target max butteraugli distance, lower = higher quality, 0 = lossless; range: 0 .. 25. Default is 1.
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       IMWRITE_JPEGXL_DECODING_SPEED = 643,//!< For JPEG XL, decoding speed tier for the provided options; minimum is 0 (slowest to decode, best quality/density), and maximum is 4 (fastest to decode, at the cost of some quality/density). Default is 0.
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       IMWRITE_BMP_COMPRESSION     = 768,  //!< For BMP, use to specify compress parameter for 32bpp image. Default is IMWRITE_BMP_COMPRESSION_BITFIELDS. See cv::ImwriteBMPCompressionFlags.
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       IMWRITE_GIF_LOOP            = 1024, //!< Not functional since 4.12.0. Replaced by cv::Animation::loop_count.
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       IMWRITE_GIF_SPEED           = 1025, //!< Not functional since 4.12.0. Replaced by cv::Animation::durations.
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       IMWRITE_GIF_QUALITY         = 1026, //!< For GIF, it can be a quality from 1 to 8. Default is 2. See cv::ImwriteGifCompressionFlags.
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       IMWRITE_GIF_DITHER          = 1027, //!< For GIF, it can be a quality from -1(most dither) to 3(no dither). Default is 0.
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       IMWRITE_GIF_TRANSPARENCY    = 1028, //!< For GIF, the alpha channel lower than this will be set to transparent. Default is 1.
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       IMWRITE_GIF_COLORTABLE      = 1029  //!< For GIF, 0 means global color table is used, 1 means local color table is used. Default is 0.
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};
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enum ImwriteJPEGSamplingFactorParams {
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       IMWRITE_JPEG_SAMPLING_FACTOR_411 = 0x411111, //!< 4x1,1x1,1x1
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       IMWRITE_JPEG_SAMPLING_FACTOR_420 = 0x221111, //!< 2x2,1x1,1x1(Default)
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       IMWRITE_JPEG_SAMPLING_FACTOR_422 = 0x211111, //!< 2x1,1x1,1x1
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       IMWRITE_JPEG_SAMPLING_FACTOR_440 = 0x121111, //!< 1x2,1x1,1x1
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       IMWRITE_JPEG_SAMPLING_FACTOR_444 = 0x111111  //!< 1x1,1x1,1x1(No subsampling)
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     };
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enum ImwriteTiffCompressionFlags {
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        IMWRITE_TIFF_COMPRESSION_NONE = 1,            //!< dump mode
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        IMWRITE_TIFF_COMPRESSION_CCITTRLE = 2,        //!< CCITT modified Huffman RLE
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        IMWRITE_TIFF_COMPRESSION_CCITTFAX3 = 3,       //!< CCITT Group 3 fax encoding
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        IMWRITE_TIFF_COMPRESSION_CCITT_T4 = 3,        //!< CCITT T.4 (TIFF 6 name)
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        IMWRITE_TIFF_COMPRESSION_CCITTFAX4 = 4,       //!< CCITT Group 4 fax encoding
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        IMWRITE_TIFF_COMPRESSION_CCITT_T6 = 4,        //!< CCITT T.6 (TIFF 6 name)
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        IMWRITE_TIFF_COMPRESSION_LZW = 5,             //!< Lempel-Ziv  & Welch
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        IMWRITE_TIFF_COMPRESSION_OJPEG = 6,           //!< !6.0 JPEG
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        IMWRITE_TIFF_COMPRESSION_JPEG = 7,            //!< %JPEG DCT compression
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        IMWRITE_TIFF_COMPRESSION_T85 = 9,             //!< !TIFF/FX T.85 JBIG compression
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        IMWRITE_TIFF_COMPRESSION_T43 = 10,            //!< !TIFF/FX T.43 colour by layered JBIG compression
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        IMWRITE_TIFF_COMPRESSION_NEXT = 32766,        //!< NeXT 2-bit RLE
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        IMWRITE_TIFF_COMPRESSION_CCITTRLEW = 32771,   //!< #1 w/ word alignment
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        IMWRITE_TIFF_COMPRESSION_PACKBITS = 32773,    //!< Macintosh RLE
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        IMWRITE_TIFF_COMPRESSION_THUNDERSCAN = 32809, //!< ThunderScan RLE
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        IMWRITE_TIFF_COMPRESSION_IT8CTPAD = 32895,    //!< IT8 CT w/padding
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        IMWRITE_TIFF_COMPRESSION_IT8LW = 32896,       //!< IT8 Linework RLE
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        IMWRITE_TIFF_COMPRESSION_IT8MP = 32897,       //!< IT8 Monochrome picture
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        IMWRITE_TIFF_COMPRESSION_IT8BL = 32898,       //!< IT8 Binary line art
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        IMWRITE_TIFF_COMPRESSION_PIXARFILM = 32908,   //!< Pixar companded 10bit LZW
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        IMWRITE_TIFF_COMPRESSION_PIXARLOG = 32909,    //!< Pixar companded 11bit ZIP
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        IMWRITE_TIFF_COMPRESSION_DEFLATE = 32946,     //!< Deflate compression, legacy tag
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        IMWRITE_TIFF_COMPRESSION_ADOBE_DEFLATE = 8,   //!< Deflate compression, as recognized by Adobe
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        IMWRITE_TIFF_COMPRESSION_DCS = 32947,         //!< Kodak DCS encoding
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        IMWRITE_TIFF_COMPRESSION_JBIG = 34661,        //!< ISO JBIG
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        IMWRITE_TIFF_COMPRESSION_SGILOG = 34676,      //!< SGI Log Luminance RLE
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        IMWRITE_TIFF_COMPRESSION_SGILOG24 = 34677,    //!< SGI Log 24-bit packed
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        IMWRITE_TIFF_COMPRESSION_JP2000 = 34712,      //!< Leadtools JPEG2000
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        IMWRITE_TIFF_COMPRESSION_LERC = 34887,        //!< ESRI Lerc codec: https://github.com/Esri/lerc
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        IMWRITE_TIFF_COMPRESSION_LZMA = 34925,        //!< LZMA2
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        IMWRITE_TIFF_COMPRESSION_ZSTD = 50000,        //!< ZSTD: WARNING not registered in Adobe-maintained registry
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        IMWRITE_TIFF_COMPRESSION_WEBP = 50001,        //!< WEBP: WARNING not registered in Adobe-maintained registry
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        IMWRITE_TIFF_COMPRESSION_JXL = 50002          //!< JPEGXL: WARNING not registered in Adobe-maintained registry
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};
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enum ImwriteTiffPredictorFlags {
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        IMWRITE_TIFF_PREDICTOR_NONE = 1,              //!< no prediction scheme used
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        IMWRITE_TIFF_PREDICTOR_HORIZONTAL = 2,        //!< horizontal differencing
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        IMWRITE_TIFF_PREDICTOR_FLOATINGPOINT = 3      //!< floating point predictor
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};
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enum ImwriteTiffResolutionUnitFlags {
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        IMWRITE_TIFF_RESOLUTION_UNIT_NONE = 1,        //!< no absolute unit of measurement.
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        IMWRITE_TIFF_RESOLUTION_UNIT_INCH = 2,        //!< inch
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        IMWRITE_TIFF_RESOLUTION_UNIT_CENTIMETER = 3,  //!< centimeter
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};
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enum ImwriteEXRTypeFlags {
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       // IMWRITE_EXR_TYPE_UNIT = 0, // not supported
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       IMWRITE_EXR_TYPE_HALF   = 1, //!< store as HALF (FP16)
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       IMWRITE_EXR_TYPE_FLOAT  = 2  //!< store as FP32 (default)
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     };
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enum ImwriteEXRCompressionFlags {
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       IMWRITE_EXR_COMPRESSION_NO    = 0, //!< no compression
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       IMWRITE_EXR_COMPRESSION_RLE   = 1, //!< run length encoding
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       IMWRITE_EXR_COMPRESSION_ZIPS  = 2, //!< zlib compression, one scan line at a time
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       IMWRITE_EXR_COMPRESSION_ZIP   = 3, //!< zlib compression, in blocks of 16 scan lines
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       IMWRITE_EXR_COMPRESSION_PIZ   = 4, //!< piz-based wavelet compression
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       IMWRITE_EXR_COMPRESSION_PXR24 = 5, //!< lossy 24-bit float compression
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       IMWRITE_EXR_COMPRESSION_B44   = 6, //!< lossy 4-by-4 pixel block compression, fixed compression rate
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       IMWRITE_EXR_COMPRESSION_B44A  = 7, //!< lossy 4-by-4 pixel block compression, flat fields are compressed more
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       IMWRITE_EXR_COMPRESSION_DWAA  = 8, //!< lossy DCT based compression, in blocks of 32 scanlines. More efficient for partial buffer access. Supported since OpenEXR 2.2.0.
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       IMWRITE_EXR_COMPRESSION_DWAB  = 9, //!< lossy DCT based compression, in blocks of 256 scanlines. More efficient space wise and faster to decode full frames than DWAA_COMPRESSION. Supported since OpenEXR 2.2.0.
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     };
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//! Imwrite PNG specific flags used to tune the compression algorithm.
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/** These flags will be modify the way of PNG image compression and will be passed to the underlying zlib processing stage.
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-   The effect of IMWRITE_PNG_STRATEGY_FILTERED is to force more Huffman coding and less string matching; it is somewhat intermediate between IMWRITE_PNG_STRATEGY_DEFAULT and IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY.
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-   IMWRITE_PNG_STRATEGY_RLE is designed to be almost as fast as IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY, but give better compression for PNG image data.
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-   The strategy parameter only affects the compression ratio but not the correctness of the compressed output even if it is not set appropriately.
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-   IMWRITE_PNG_STRATEGY_FIXED prevents the use of dynamic Huffman codes, allowing for a simpler decoder for special applications.
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*/
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enum ImwritePNGFlags {
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       IMWRITE_PNG_STRATEGY_DEFAULT      = 0, //!< Use this value for normal data.
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       IMWRITE_PNG_STRATEGY_FILTERED     = 1, //!< Use this value for data produced by a filter (or predictor).Filtered data consists mostly of small values with a somewhat random distribution. In this case, the compression algorithm is tuned to compress them better.
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       IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY = 2, //!< Use this value to force Huffman encoding only (no string match).
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       IMWRITE_PNG_STRATEGY_RLE          = 3, //!< Use this value to limit match distances to one (run-length encoding).
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       IMWRITE_PNG_STRATEGY_FIXED        = 4  //!< Using this value prevents the use of dynamic Huffman codes, allowing for a simpler decoder for special applications.
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     };
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//! Imwrite PNG specific values for IMWRITE_PNG_FILTER parameter key
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enum ImwritePNGFilterFlags {
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       IMWRITE_PNG_FILTER_NONE           = 8,   //!< Applies no filter to the PNG image (useful when you want to save the raw pixel data without any compression filter).
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       IMWRITE_PNG_FILTER_SUB            = 16,  //!< Applies the "sub" filter, which calculates the difference between the current byte and the previous byte in the row.
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       IMWRITE_PNG_FILTER_UP             = 32,  //!< applies the "up" filter, which calculates the difference between the current byte and the corresponding byte directly above it.
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       IMWRITE_PNG_FILTER_AVG            = 64,  //!< applies the "average" filter, which calculates the average of the byte to the left and the byte above.
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       IMWRITE_PNG_FILTER_PAETH          = 128, //!< applies the "Paeth" filter, a more complex filter that predicts the next pixel value based on neighboring pixels.
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       IMWRITE_PNG_FAST_FILTERS          = (IMWRITE_PNG_FILTER_NONE | IMWRITE_PNG_FILTER_SUB | IMWRITE_PNG_FILTER_UP), //!< This is a combination of IMWRITE_PNG_FILTER_NONE, IMWRITE_PNG_FILTER_SUB, and IMWRITE_PNG_FILTER_UP, typically used for faster compression.
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       IMWRITE_PNG_ALL_FILTERS           = (IMWRITE_PNG_FAST_FILTERS | IMWRITE_PNG_FILTER_AVG | IMWRITE_PNG_FILTER_PAETH) //!< This combines all available filters (NONE, SUB, UP, AVG, and PAETH), which will attempt to apply all of them for the best possible compression.
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     };
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//! Imwrite PAM specific tupletype flags used to define the 'TUPLETYPE' field of a PAM file.
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enum ImwritePAMFlags {
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       IMWRITE_PAM_FORMAT_NULL            = 0,
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       IMWRITE_PAM_FORMAT_BLACKANDWHITE   = 1,
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       IMWRITE_PAM_FORMAT_GRAYSCALE       = 2,
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       IMWRITE_PAM_FORMAT_GRAYSCALE_ALPHA = 3,
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       IMWRITE_PAM_FORMAT_RGB             = 4,
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       IMWRITE_PAM_FORMAT_RGB_ALPHA       = 5
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     };
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//! Imwrite HDR specific values for IMWRITE_HDR_COMPRESSION parameter key
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enum ImwriteHDRCompressionFlags {
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    IMWRITE_HDR_COMPRESSION_NONE = 0,
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    IMWRITE_HDR_COMPRESSION_RLE = 1
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};
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//! Imwrite BMP specific values for IMWRITE_BMP_COMPRESSION parameter key.
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enum ImwriteBMPCompressionFlags {
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    IMWRITE_BMP_COMPRESSION_RGB = 0,       //!< Use BI_RGB. OpenCV v4.12.0 or before supports to encode with this compression only.
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    IMWRITE_BMP_COMPRESSION_BITFIELDS = 3, //!< Use BI_BITFIELDS. OpenCV v4.13.0 or later can support to encode with this compression. (only for 32 BPP images)
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};
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//! Imwrite GIF specific values for IMWRITE_GIF_QUALITY parameter key, if larger than 3, then its related to the size of the color table.
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enum ImwriteGIFCompressionFlags {
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    IMWRITE_GIF_FAST_NO_DITHER       = 1,
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    IMWRITE_GIF_FAST_FLOYD_DITHER    = 2,
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    IMWRITE_GIF_COLORTABLE_SIZE_8    = 3,
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    IMWRITE_GIF_COLORTABLE_SIZE_16   = 4,
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    IMWRITE_GIF_COLORTABLE_SIZE_32   = 5,
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    IMWRITE_GIF_COLORTABLE_SIZE_64   = 6,
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    IMWRITE_GIF_COLORTABLE_SIZE_128  = 7,
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    IMWRITE_GIF_COLORTABLE_SIZE_256  = 8
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};
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enum ImageMetadataType
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{
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    IMAGE_METADATA_UNKNOWN = -1, // Used when metadata type is unrecognized or not set
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    IMAGE_METADATA_EXIF = 0,     // EXIF metadata (e.g., camera info, GPS, orientation)
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    IMAGE_METADATA_XMP = 1,      // XMP metadata (eXtensible Metadata Platform - Adobe format)
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    IMAGE_METADATA_ICCP = 2,     // ICC Profile (color profile for color management)
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    IMAGE_METADATA_CICP = 3,     // cICP Profile (video signal type)
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    IMAGE_METADATA_MAX = 3       // Highest valid index (usually used for bounds checking)
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};
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//! @} imgcodecs_flags
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/** @brief Represents an animation with multiple frames.
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The `Animation` struct is designed to store and manage data for animated sequences such as those from animated formats (e.g., GIF, AVIF, APNG, WebP).
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It provides support for looping, background color settings, frame timing, and frame storage.
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*/
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struct CV_EXPORTS_W_SIMPLE Animation
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{
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    //! Number of times the animation should loop. 0 means infinite looping.
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    /*! @note At some file format, when N is set, whether it is displayed N or N+1 times depends on the implementation of the user application. This loop times behaviour has not been documented clearly.
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     *  - (GIF) See https://issues.chromium.org/issues/40459899
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     *    And animated GIF with loop is extended with the Netscape Application Block(NAB), which it not a part of GIF89a specification. See https://en.wikipedia.org/wiki/GIF#Animated_GIF .
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     *  - (WebP) See https://issues.chromium.org/issues/41276895
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     */
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    CV_PROP_RW int loop_count;
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    //! Background color of the animation in BGRA format.
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    CV_PROP_RW Scalar bgcolor;
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    //! Duration for each frame in milliseconds.
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    /*! @note (GIF) Due to file format limitation
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     *  - Durations must be multiples of 10 milliseconds. Any provided value will be rounded down to the nearest 10ms (e.g., 88ms → 80ms).
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     *  - 0ms(or smaller than expected in user application) duration may cause undefined behavior, e.g. it is handled with default duration.
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     *  - Over 65535 * 10 milliseconds duration is not supported.
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     */
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    CV_PROP_RW std::vector<int> durations;
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    //! Vector of frames, where each Mat represents a single frame.
304
    CV_PROP_RW std::vector<Mat> frames;
305
    //! image that can be used for the format in addition to the animation or if animation is not supported in the reader (like in PNG).
306
    CV_PROP_RW Mat still_image;
307
308
    /** @brief Constructs an Animation object with optional loop count and background color.
309
310
    @param loopCount An integer representing the number of times the animation should loop:
311
    - `0` (default) indicates infinite looping, meaning the animation will replay continuously.
312
    - Positive values denote finite repeat counts, allowing the animation to play a limited number of times.
313
    - If a negative value or a value beyond the maximum of `0xffff` (65535) is provided, it is reset to `0`
314
    (infinite looping) to maintain valid bounds.
315
316
    @param bgColor A `Scalar` object representing the background color in BGR format:
317
    - Defaults to `Scalar()`, indicating an empty color (usually transparent if supported).
318
    - This background color provides a solid fill behind frames that have transparency, ensuring a consistent display appearance.
319
    */
320
    CV_WRAP Animation(int loopCount = 0, Scalar bgColor = Scalar());
321
};
322
323
/** @brief Loads an image from a file.
324
325
@anchor imread
326
327
The `imread` function loads an image from the specified file and returns OpenCV matrix. If the image cannot be
328
read (because of a missing file, improper permissions, or unsupported/invalid format), the function
329
returns an empty matrix.
330
331
Currently, the following file formats are supported:
332
333
-   Windows bitmaps - \*.bmp, \*.dib (always supported)
334
-   GIF files - \*.gif (always supported)
335
-   JPEG files - \*.jpeg, \*.jpg, \*.jpe (see the *Note* section)
336
-   JPEG 2000 files - \*.jp2 (see the *Note* section)
337
-   Portable Network Graphics - \*.png (see the *Note* section)
338
-   WebP - \*.webp (see the *Note* section)
339
-   AVIF - \*.avif (see the *Note* section)
340
-   Portable image format - \*.pbm, \*.pgm, \*.ppm, \*.pxm, \*.pnm (always supported)
341
-   PFM files - \*.pfm (see the *Note* section)
342
-   Sun rasters - \*.sr, \*.ras (always supported)
343
-   TIFF files - \*.tiff, \*.tif (see the *Note* section)
344
-   OpenEXR Image files - \*.exr (see the *Note* section)
345
-   Radiance HDR - \*.hdr, \*.pic (always supported)
346
-   Raster and Vector geospatial data supported by GDAL (see the *Note* section)
347
348
@note
349
-   The function determines the type of an image by its content, not by the file extension.
350
-   In the case of color images, the decoded images will have the channels stored in **B G R** order.
351
-   When using IMREAD_GRAYSCALE, the codec's internal grayscale conversion will be used, if available.
352
    Results may differ from the output of cvtColor().
353
-   On Microsoft Windows\* and Mac OS\*, the codecs shipped with OpenCV (libjpeg, libpng, libtiff,
354
    and libjasper) are used by default. So, OpenCV can always read JPEGs, PNGs, and TIFFs. On Mac OS,
355
    there is also an option to use native Mac OS image readers. However, beware that currently these
356
    native image loaders give images with different pixel values because of the color management embedded
357
    into Mac OS.
358
-   On Linux\*, BSD flavors, and other Unix-like open-source operating systems, OpenCV looks for
359
    codecs supplied with the OS. Ensure the relevant packages are installed (including development
360
    files, such as "libjpeg-dev" in Debian\* and Ubuntu\*) to get codec support, or turn
361
    on the OPENCV_BUILD_3RDPARTY_LIBS flag in CMake.
362
-   If the *WITH_GDAL* flag is set to true in CMake and @ref IMREAD_LOAD_GDAL is used to load the image,
363
    the [GDAL](http://www.gdal.org) driver will be used to decode the image, supporting
364
    [Raster](http://www.gdal.org/formats_list.html) and [Vector](http://www.gdal.org/ogr_formats.html) formats.
365
-   If EXIF information is embedded in the image file, the EXIF orientation will be taken into account,
366
    and thus the image will be rotated accordingly unless the flags @ref IMREAD_IGNORE_ORIENTATION
367
    or @ref IMREAD_UNCHANGED are passed.
368
-   Use the IMREAD_UNCHANGED flag to preserve the floating-point values from PFM images.
369
-   By default, the number of pixels must be less than 2^30. This limit can be changed by setting
370
    the environment variable `OPENCV_IO_MAX_IMAGE_PIXELS`. See @ref tutorial_env_reference.
371
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@param filename Name of the file to be loaded.
373
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_COLOR_BGR.
374
*/
375
CV_EXPORTS_W Mat imread( const String& filename, int flags = IMREAD_COLOR_BGR );
376
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/** @brief Loads an image from a file.
378
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This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts and the return value.
380
@param filename Name of file to be loaded.
381
@param dst object in which the image will be loaded.
382
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_COLOR_BGR.
383
@note
384
The image passing through the img parameter can be pre-allocated. The memory is reused if the shape and the type match with the load image.
385
 */
386
CV_EXPORTS_W void imread( const String& filename, OutputArray dst, int flags = IMREAD_COLOR_BGR );
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/** @brief Reads an image from a file along with associated metadata.
389
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This function behaves similarly to cv::imread(), loading an image from the specified file.
391
In addition to the image pixel data, it also attempts to extract any available metadata
392
embedded in the file (such as EXIF, XMP, etc.), depending on file format support.
393
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@note In the case of color images, the decoded images will have the channels stored in **B G R** order.
395
@param filename Name of the file to be loaded.
396
@param metadataTypes Output vector with types of metadata chunks returned in metadata, see ImageMetadataType.
397
@param metadata Output vector of vectors or vector of matrices to store the retrieved metadata.
398
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR.
399
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@return The loaded image as a cv::Mat object. If the image cannot be read, the function returns an empty matrix.
401
*/
402
CV_EXPORTS_W Mat imreadWithMetadata( const String& filename, CV_OUT std::vector<int>& metadataTypes,
403
                                     OutputArrayOfArrays metadata, int flags = IMREAD_ANYCOLOR);
404
405
/** @brief Loads a multi-page image from a file.
406
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The function imreadmulti loads a multi-page image from the specified file into a vector of Mat objects.
408
@param filename Name of file to be loaded.
409
@param mats A vector of Mat objects holding each page.
410
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR.
411
@sa cv::imread
412
*/
413
CV_EXPORTS_W bool imreadmulti(const String& filename, CV_OUT std::vector<Mat>& mats, int flags = IMREAD_ANYCOLOR);
414
415
/** @brief Loads images of a multi-page image from a file.
416
417
The function imreadmulti loads a specified range from a multi-page image from the specified file into a vector of Mat objects.
418
@param filename Name of file to be loaded.
419
@param mats A vector of Mat objects holding each page.
420
@param start Start index of the image to load
421
@param count Count number of images to load
422
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR.
423
@sa cv::imread
424
*/
425
CV_EXPORTS_W bool imreadmulti(const String& filename, CV_OUT std::vector<Mat>& mats, int start, int count, int flags = IMREAD_ANYCOLOR);
426
427
/** @example samples/cpp/tutorial_code/imgcodecs/animations.cpp
428
An example to show usage of cv::imreadanimation and cv::imwriteanimation functions.
429
Check @ref tutorial_animations "the corresponding tutorial" for more details
430
*/
431
432
/** @brief Loads frames from an animated image file into an Animation structure.
433
434
The function imreadanimation loads frames from an animated image file (e.g., GIF, AVIF, APNG, WEBP) into the provided Animation struct.
435
436
@param filename A string containing the path to the file.
437
@param animation A reference to an Animation structure where the loaded frames will be stored. It should be initialized before the function is called.
438
@param start The index of the first frame to load. This is optional and defaults to 0.
439
@param count The number of frames to load. This is optional and defaults to 32767.
440
441
@return Returns true if the file was successfully loaded and frames were extracted; returns false otherwise.
442
*/
443
CV_EXPORTS_W bool imreadanimation(const String& filename, CV_OUT Animation& animation, int start = 0, int count = INT16_MAX);
444
445
/** @brief Loads frames from an animated image buffer into an Animation structure.
446
447
The function imdecodeanimation loads frames from an animated image buffer (e.g., GIF, AVIF, APNG, WEBP) into the provided Animation struct.
448
449
@param buf A reference to an InputArray containing the image buffer.
450
@param animation A reference to an Animation structure where the loaded frames will be stored. It should be initialized before the function is called.
451
@param start The index of the first frame to load. This is optional and defaults to 0.
452
@param count The number of frames to load. This is optional and defaults to 32767.
453
454
@return Returns true if the buffer was successfully loaded and frames were extracted; returns false otherwise.
455
*/
456
CV_EXPORTS_W bool imdecodeanimation(InputArray buf, CV_OUT Animation& animation, int start = 0, int count = INT16_MAX);
457
458
/** @brief Saves an Animation to a specified file.
459
460
The function imwriteanimation saves the provided Animation data to the specified file in an animated format.
461
Supported formats depend on the implementation and may include formats like GIF, AVIF, APNG, or WEBP.
462
463
@param filename The name of the file where the animation will be saved. The file extension determines the format.
464
@param animation A constant reference to an Animation struct containing the frames and metadata to be saved.
465
@param params Optional format-specific parameters encoded as pairs (paramId_1, paramValue_1, paramId_2, paramValue_2, ...).
466
These parameters are used to specify additional options for the encoding process. Refer to `cv::ImwriteFlags` for details on possible parameters.
467
468
@return Returns true if the animation was successfully saved; returns false otherwise.
469
*/
470
CV_EXPORTS_W bool imwriteanimation(const String& filename, const Animation& animation, const std::vector<int>& params = std::vector<int>());
471
472
/** @brief Encodes an Animation to a memory buffer.
473
474
The function imencodeanimation encodes the provided Animation data into a memory
475
buffer in an animated format. Supported formats depend on the implementation and
476
may include formats like GIF, AVIF, APNG, or WEBP.
477
478
@param ext The file extension that determines the format of the encoded data.
479
@param animation A constant reference to an Animation struct containing the
480
frames and metadata to be encoded.
481
@param buf A reference to a vector of unsigned chars where the encoded data will
482
be stored.
483
@param params Optional format-specific parameters encoded as pairs (paramId_1,
484
paramValue_1, paramId_2, paramValue_2, ...). These parameters are used to
485
specify additional options for the encoding process. Refer to `cv::ImwriteFlags`
486
for details on possible parameters.
487
488
@return Returns true if the animation was successfully encoded; returns false otherwise.
489
*/
490
CV_EXPORTS_W bool imencodeanimation(const String& ext, const Animation& animation, CV_OUT std::vector<uchar>& buf, const std::vector<int>& params = std::vector<int>());
491
492
/** @brief Returns the number of images inside the given file
493
494
The function imcount returns the number of pages in a multi-page image (e.g. TIFF), the number of frames in an animation (e.g. AVIF), and 1 otherwise.
495
If the image cannot be decoded, 0 is returned.
496
@param filename Name of file to be loaded.
497
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR.
498
@todo when cv::IMREAD_LOAD_GDAL flag used the return value will be 0 or 1 because OpenCV's GDAL decoder doesn't support multi-page reading yet.
499
*/
500
CV_EXPORTS_W size_t imcount(const String& filename, int flags = IMREAD_ANYCOLOR);
501
502
/** @brief Saves an image to a specified file.
503
504
The function imwrite saves the image to the specified file. The image format is chosen based on the
505
filename extension (see cv::imread for the list of extensions). In general, only 8-bit unsigned (CV_8U)
506
single-channel or 3-channel (with 'BGR' channel order) images
507
can be saved using this function, with these exceptions:
508
509
- With BMP encoder, 8-bit unsigned (CV_8U) images can be saved.
510
  - BMP images with an alpha channel can be saved using this function.
511
    To achieve this, create an 8-bit 4-channel (CV_8UC4) BGRA image, ensuring the alpha channel is the last component.
512
    Fully transparent pixels should have an alpha value of 0, while fully opaque pixels should have an alpha value of 255.
513
    OpenCV v4.13.0 or later use BI_BITFIELDS compression as default. See IMWRITE_BMP_COMPRESSION.
514
- With OpenEXR encoder, only 32-bit float (CV_32F) images can be saved. More than 4 channels can be saved. (imread can load it then.)
515
  - 8-bit unsigned (CV_8U) images are not supported.
516
- With Radiance HDR encoder, non 64-bit float (CV_64F) images can be saved.
517
  - All images will be converted to 32-bit float (CV_32F).
518
- With JPEG 2000 encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
519
- With JPEG XL encoder, 8-bit unsigned (CV_8U), 16-bit unsigned (CV_16U) and 32-bit float(CV_32F) images can be saved.
520
  - JPEG XL images with an alpha channel can be saved using this function.
521
    To achieve this, create an 8-bit 4-channel (CV_8UC4) / 16-bit 4-channel (CV_16UC4) / 32-bit float 4-channel (CV_32FC4) BGRA image, ensuring the alpha channel is the last component.
522
    Fully transparent pixels should have an alpha value of 0, while fully opaque pixels should have an alpha value of 255/65535/1.0.
523
- With PAM encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
524
- With PNG encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
525
  - PNG images with an alpha channel can be saved using this function.
526
    To achieve this, create an 8-bit 4-channel (CV_8UC4) / 16-bit 4-channel (CV_16UC4) BGRA image, ensuring the alpha channel is the last component.
527
    Fully transparent pixels should have an alpha value of 0, while fully opaque pixels should have an alpha value of 255/65535(see the code sample below).
528
- With PGM/PPM encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
529
- With TIFF encoder, 8-bit unsigned (CV_8U), 8-bit signed (CV_8S),
530
                     16-bit unsigned (CV_16U), 16-bit signed (CV_16S),
531
                     32-bit signed (CV_32S),
532
                     32-bit float (CV_32F) and 64-bit float (CV_64F) images can be saved.
533
  - Multiple images (vector of Mat) can be saved in TIFF format (see the code sample below).
534
  - 32-bit float 3-channel (CV_32FC3) TIFF images will be saved
535
    using the LogLuv high dynamic range encoding (4 bytes per pixel)
536
- With GIF encoder, 8-bit unsigned (CV_8U) images can be saved.
537
  - GIF images with an alpha channel can be saved using this function.
538
    To achieve this, create an 8-bit 4-channel (CV_8UC4) BGRA image, ensuring the alpha channel is the last component.
539
    Fully transparent pixels should have an alpha value of 0, while fully opaque pixels should have an alpha value of 255.
540
  - 8-bit single-channel images (CV_8UC1) are not supported due to GIF's limitation to indexed color formats.
541
542
If the image format is not supported, the image will be converted to 8-bit unsigned (CV_8U) and saved that way.
543
544
If the format, depth or channel order is different, use
545
Mat::convertTo and cv::cvtColor to convert it before saving. Or, use the universal FileStorage I/O
546
functions to save the image to XML or YAML format.
547
548
The sample below shows how to create a BGRA image, how to set custom compression parameters and save it to a PNG file.
549
It also demonstrates how to save multiple images in a TIFF file:
550
@include snippets/imgcodecs_imwrite.cpp
551
@param filename Name of the file.
552
@param img (Mat or vector of Mat) Image or Images to be saved.
553
@param params Format-specific parameters encoded as pairs (paramId_1, paramValue_1, paramId_2, paramValue_2, ... .) see cv::ImwriteFlags
554
*/
555
CV_EXPORTS_W bool imwrite( const String& filename, InputArray img,
556
              const std::vector<int>& params = std::vector<int>());
557
558
/** @brief Saves an image to a specified file with metadata
559
560
The function imwriteWithMetadata saves the image to the specified file. It does the same thing as imwrite, but additionally writes metadata if the corresponding format supports it.
561
@param filename Name of the file. As with imwrite, image format is determined by the file extension.
562
@param img (Mat or vector of Mat) Image or Images to be saved.
563
@param metadataTypes Vector with types of metadata chucks stored in metadata to write, see ImageMetadataType.
564
@param metadata Vector of vectors or vector of matrices with chunks of metadata to store into the file
565
@param params Format-specific parameters encoded as pairs (paramId_1, paramValue_1, paramId_2, paramValue_2, ... .) see cv::ImwriteFlags
566
*/
567
CV_EXPORTS_W bool imwriteWithMetadata( const String& filename, InputArray img,
568
                                       const std::vector<int>& metadataTypes,
569
                                       InputArrayOfArrays& metadata,
570
                                       const std::vector<int>& params = std::vector<int>());
571
572
//! @brief multi-image overload for bindings
573
CV_WRAP static inline
574
bool imwritemulti(const String& filename, InputArrayOfArrays img,
575
                  const std::vector<int>& params = std::vector<int>())
576
0
{
577
0
    return imwrite(filename, img, params);
578
0
}
Unexecuted instantiation: generateusergallerycollage_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
Unexecuted instantiation: imread_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
Unexecuted instantiation: imdecode_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
Unexecuted instantiation: filestorage_read_string_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
Unexecuted instantiation: filestorage_read_file_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
Unexecuted instantiation: core_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
Unexecuted instantiation: imencode_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
Unexecuted instantiation: filestorage_read_filename_fuzzer.cc:cv::imwritemulti(std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> > const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)
579
580
/** @brief Reads an image from a buffer in memory.
581
582
The function imdecode reads an image from the specified buffer in the memory. If the buffer is too short or
583
contains invalid data, the function returns an empty matrix ( Mat::data==NULL ).
584
585
See cv::imread for the list of supported formats and flags description.
586
587
@note In the case of color images, the decoded images will have the channels stored in **B G R** order.
588
@param buf Input array or vector of bytes.
589
@param flags Flag that can take values of cv::ImreadModes.
590
*/
591
CV_EXPORTS_W Mat imdecode( InputArray buf, int flags );
592
593
/** @brief Reads an image from a memory buffer and extracts associated metadata.
594
595
This function decodes an image from the specified memory buffer. If the buffer is too short or
596
contains invalid data, the function returns an empty matrix ( Mat::data==NULL ).
597
598
See cv::imread for the list of supported formats and flags description.
599
600
@note In the case of color images, the decoded images will have the channels stored in **B G R** order.
601
@param buf Input array or vector of bytes containing the encoded image data.
602
@param metadataTypes Output vector with types of metadata chucks returned in metadata, see cv::ImageMetadataType
603
@param metadata Output vector of vectors or vector of matrices to store the retrieved metadata
604
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR.
605
606
@return The decoded image as a cv::Mat object. If decoding fails, the function returns an empty matrix.
607
*/
608
CV_EXPORTS_W Mat imdecodeWithMetadata( InputArray buf, CV_OUT std::vector<int>& metadataTypes,
609
                                       OutputArrayOfArrays metadata, int flags = IMREAD_ANYCOLOR );
610
611
/** @overload
612
@param buf Input array or vector of bytes.
613
@param flags Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR.
614
@param dst The optional output placeholder for the decoded matrix. It can save the image
615
reallocations when the function is called repeatedly for images of the same size. In case of decoder
616
failure the function returns empty cv::Mat object, but does not release user-provided dst buffer.
617
*/
618
CV_EXPORTS Mat imdecode( InputArray buf, int flags, Mat* dst);
619
620
/** @brief Reads a multi-page image from a buffer in memory.
621
622
The function imdecodemulti reads a multi-page image from the specified buffer in the memory. If the buffer is too short or
623
contains invalid data, the function returns false.
624
625
See cv::imreadmulti for the list of supported formats and flags description.
626
627
@note In the case of color images, the decoded images will have the channels stored in **B G R** order.
628
@param buf Input array or vector of bytes.
629
@param flags Flag that can take values of cv::ImreadModes.
630
@param mats A vector of Mat objects holding each page, if more than one.
631
@param range A continuous selection of pages.
632
*/
633
CV_EXPORTS_W bool imdecodemulti(InputArray buf, int flags, CV_OUT std::vector<Mat>& mats, const cv::Range& range = Range::all());
634
635
/** @brief Encodes an image into a memory buffer.
636
637
The function imencode compresses the image and stores it in the memory buffer that is resized to fit the
638
result. See cv::imwrite for the list of supported formats and flags description.
639
640
@param ext File extension that defines the output format. Must include a leading period.
641
@param img Image to be compressed.
642
@param buf Output buffer resized to fit the compressed image.
643
@param params Format-specific parameters. See cv::imwrite and cv::ImwriteFlags.
644
*/
645
CV_EXPORTS_W bool imencode( const String& ext, InputArray img,
646
                            CV_OUT std::vector<uchar>& buf,
647
                            const std::vector<int>& params = std::vector<int>());
648
649
/** @brief Encodes an image into a memory buffer.
650
651
The function imencode compresses the image and stores it in the memory buffer that is resized to fit the
652
result. See cv::imwrite for the list of supported formats and flags description.
653
654
@param ext File extension that defines the output format. Must include a leading period.
655
@param img Image to be compressed.
656
@param metadataTypes Vector with types of metadata chucks stored in metadata to write, see ImageMetadataType.
657
@param metadata Vector of vectors or vector of matrices with chunks of metadata to store into the file
658
@param buf Output buffer resized to fit the compressed image.
659
@param params Format-specific parameters. See cv::imwrite and cv::ImwriteFlags.
660
*/
661
CV_EXPORTS_W bool imencodeWithMetadata( const String& ext, InputArray img,
662
                                        const std::vector<int>& metadataTypes,
663
                                        InputArrayOfArrays metadata,
664
                                        CV_OUT std::vector<uchar>& buf,
665
                                        const std::vector<int>& params = std::vector<int>());
666
667
/** @brief Encodes array of images into a memory buffer.
668
669
The function is analog to cv::imencode for in-memory multi-page image compression.
670
See cv::imwrite for the list of supported formats and flags description.
671
672
@param ext File extension that defines the output format. Must include a leading period.
673
@param imgs Vector of images to be written.
674
@param buf Output buffer resized to fit the compressed data.
675
@param params Format-specific parameters. See cv::imwrite and cv::ImwriteFlags.
676
*/
677
CV_EXPORTS_W bool imencodemulti( const String& ext, InputArrayOfArrays imgs,
678
                                 CV_OUT std::vector<uchar>& buf,
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                                 const std::vector<int>& params = std::vector<int>());
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/** @brief Checks if the specified image file can be decoded by OpenCV.
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The function haveImageReader checks if OpenCV is capable of reading the specified file.
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This can be useful for verifying support for a given image format before attempting to load an image.
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@param filename The name of the file to be checked.
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@return true if an image reader for the specified file is available and the file can be opened, false otherwise.
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@note The function checks the availability of image codecs that are either built into OpenCV or dynamically loaded.
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It does not load the image codec implementation and decode data, but uses signature check.
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If the file cannot be opened or the format is unsupported, the function will return false.
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@sa cv::haveImageWriter, cv::imread, cv::imdecode
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*/
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CV_EXPORTS_W bool haveImageReader( const String& filename );
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/** @brief Checks if the specified image file or specified file extension can be encoded by OpenCV.
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The function haveImageWriter checks if OpenCV is capable of writing images with the specified file extension.
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This can be useful for verifying support for a given image format before attempting to save an image.
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@param filename The name of the file or the file extension (e.g., ".jpg", ".png").
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It is recommended to provide the file extension rather than the full file name.
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@return true if an image writer for the specified extension is available, false otherwise.
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@note The function checks the availability of image codecs that are either built into OpenCV or dynamically loaded.
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It does not check for the actual existence of the file but rather the ability to write files of the given type.
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@sa cv::haveImageReader, cv::imwrite, cv::imencode
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*/
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CV_EXPORTS_W bool haveImageWriter( const String& filename );
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/** @brief To read multi-page images on demand
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The ImageCollection class provides iterator API to read multi-page images on demand. Create iterator
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to the collection of the images and iterate over the collection. Decode the necessary page with operator*.
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The performance of page decoding is O(1) if collection is increment sequentially. If the user wants to access random page,
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then the time Complexity is O(n) because the collection has to be reinitialized every time in order to go to the correct page.
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However, the intermediate pages are not decoded during the process, so typically it's quite fast.
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This is required because multi-page codecs does not support going backwards.
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After decoding the one page, it is stored inside the collection cache. Hence, trying to get Mat object from already decoded page is O(1).
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If you need memory, you can use .releaseCache() method to release cached index.
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The space complexity is O(n) if all pages are decoded into memory. The user is able to decode and release images on demand.
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*/
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class CV_EXPORTS ImageCollection {
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public:
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    struct CV_EXPORTS iterator {
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        iterator(ImageCollection* col);
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        iterator(ImageCollection* col, int end);
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        Mat& operator*();
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        Mat* operator->();
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        iterator& operator++();
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        iterator operator++(int);
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0
        friend bool operator== (const iterator& a, const iterator& b) { return a.m_curr == b.m_curr; }
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0
        friend bool operator!= (const iterator& a, const iterator& b) { return a.m_curr != b.m_curr; }
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    private:
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        ImageCollection* m_pCollection;
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        int m_curr;
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    };
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    ImageCollection();
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    ImageCollection(const String& filename, int flags);
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    void init(const String& img, int flags);
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    size_t size() const;
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    const Mat& at(int index);
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    const Mat& operator[](int index);
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    void releaseCache(int index);
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    iterator begin();
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    iterator end();
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    class Impl;
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    Ptr<Impl> getImpl();
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protected:
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    Ptr<Impl> pImpl;
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};
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//! @} imgcodecs
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} // cv
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#endif //OPENCV_IMGCODECS_HPP