Module imgcodecs Copy item path Source Expand description § Image file reading and writing§ Flags used for image file reading and writing§ iOS glue§ MacOS(OSX) glueprelude Animation Represents an animation with multiple frames.
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).
It provides support for looping, background color settings, frame timing, and frame storage. ImageCollection To read multi-page images on demand ImageCollection_iterator ImreadModes Imread flags ImwriteEXRCompressionFlags ImwriteEXRTypeFlags ImwriteFlags Imwrite flags ImwriteGIFCompressionFlags Imwrite GIF specific values for IMWRITE_GIF_QUALITY parameter key, if larger than 3, then its related to the size of the color table. ImwriteHDRCompressionFlags Imwrite HDR specific values for IMWRITE_HDR_COMPRESSION parameter key ImwriteJPEGSamplingFactorParams ImwritePAMFlags Imwrite PAM specific tupletype flags used to define the ‘TUPLETYPE’ field of a PAM file. ImwritePNGFlags Imwrite PNG specific flags used to tune the compression algorithm.
These flags will be modify the way of PNG image compression and will be passed to the underlying zlib processing stage. ImwriteTiffCompressionFlags ImwriteTiffPredictorFlags IMREAD_ANYCOLOR If set, the image is read in any possible color format. IMREAD_ANYDEPTH If set, return 16-bit/32-bit image when the input has the corresponding depth, otherwise convert it to 8-bit. IMREAD_COLOR Same as IMREAD_COLOR_BGR. IMREAD_COLOR_BGR If set, always convert image to the 3 channel BGR color image. IMREAD_COLOR_RGB If set, always convert image to the 3 channel RGB color image. IMREAD_GRAYSCALE If set, always convert image to the single channel grayscale image (codec internal conversion). IMREAD_IGNORE_ORIENTATION If set, do not rotate the image according to EXIF’s orientation flag. IMREAD_LOAD_GDAL If set, use the gdal driver for loading the image. IMREAD_REDUCED_COLOR_2 If set, always convert image to the 3 channel BGR color image and the image size reduced 1/2. IMREAD_REDUCED_COLOR_4 If set, always convert image to the 3 channel BGR color image and the image size reduced 1/4. IMREAD_REDUCED_COLOR_8 If set, always convert image to the 3 channel BGR color image and the image size reduced 1/8. IMREAD_REDUCED_GRAYSCALE_2 If set, always convert image to the single channel grayscale image and the image size reduced 1/2. IMREAD_REDUCED_GRAYSCALE_4 If set, always convert image to the single channel grayscale image and the image size reduced 1/4. IMREAD_REDUCED_GRAYSCALE_8 If set, always convert image to the single channel grayscale image and the image size reduced 1/8. IMREAD_UNCHANGED If set, return the loaded image as is (with alpha channel, otherwise it gets cropped). Ignore EXIF orientation. IMWRITE_AVIF_DEPTH For AVIF, it can be 8, 10 or 12. If >8, it is stored/read as CV_32F. Default is 8. IMWRITE_AVIF_QUALITY For AVIF, it can be a quality between 0 and 100 (the higher the better). Default is 95. IMWRITE_AVIF_SPEED For AVIF, it is between 0 (slowest) and (fastest). Default is 9. IMWRITE_EXR_COMPRESSION override EXR compression type (ZIP_COMPRESSION = 3 is default) IMWRITE_EXR_COMPRESSION_B44 lossy 4-by-4 pixel block compression, fixed compression rate IMWRITE_EXR_COMPRESSION_B44A lossy 4-by-4 pixel block compression, flat fields are compressed more IMWRITE_EXR_COMPRESSION_DWAA lossy DCT based compression, in blocks of 32 scanlines. More efficient for partial buffer access. Supported since OpenEXR 2.2.0. IMWRITE_EXR_COMPRESSION_DWAB 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. IMWRITE_EXR_COMPRESSION_NO no compression IMWRITE_EXR_COMPRESSION_PIZ piz-based wavelet compression IMWRITE_EXR_COMPRESSION_PXR24 lossy 24-bit float compression IMWRITE_EXR_COMPRESSION_RLE run length encoding IMWRITE_EXR_COMPRESSION_ZIP zlib compression, in blocks of 16 scan lines IMWRITE_EXR_COMPRESSION_ZIPS zlib compression, one scan line at a time IMWRITE_EXR_DWA_COMPRESSION_LEVEL override EXR DWA compression level (45 is default) IMWRITE_EXR_TYPE override EXR storage type (FLOAT (FP32) is default) IMWRITE_EXR_TYPE_FLOAT store as FP32 (default) IMWRITE_EXR_TYPE_HALF store as HALF (FP16) IMWRITE_GIF_COLORTABLE For GIF, 0 means global color table is used, 1 means local color table is used. Default is 0. IMWRITE_GIF_COLORTABLE_SIZE_8 IMWRITE_GIF_COLORTABLE_SIZE_16 IMWRITE_GIF_COLORTABLE_SIZE_32 IMWRITE_GIF_COLORTABLE_SIZE_64 IMWRITE_GIF_COLORTABLE_SIZE_128 IMWRITE_GIF_COLORTABLE_SIZE_256 IMWRITE_GIF_DITHER For GIF, it can be a quality from -1(most dither) to 3(no dither). Default is 0. IMWRITE_GIF_FAST_FLOYD_DITHER IMWRITE_GIF_FAST_NO_DITHER IMWRITE_GIF_LOOP For GIF, it can be a loop flag from 0 to 65535. Default is 0 - loop forever. IMWRITE_GIF_QUALITY For GIF, it can be a quality from 1 to 8. Default is 2. See cv::ImwriteGifCompressionFlags. IMWRITE_GIF_SPEED For GIF, it is between 1 (slowest) and 100 (fastest). Default is 96. IMWRITE_GIF_TRANSPARENCY For GIF, the alpha channel lower than this will be set to transparent. Default is 1. IMWRITE_HDR_COMPRESSION specify HDR compression IMWRITE_HDR_COMPRESSION_NONE IMWRITE_HDR_COMPRESSION_RLE IMWRITE_JPEG2000_COMPRESSION_X1000 For JPEG2000, use to specify the target compression rate (multiplied by 1000). The value can be from 0 to 1000. Default is 1000. IMWRITE_JPEGXL_DECODING_SPEED 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. IMWRITE_JPEGXL_DISTANCE For JPEG XL, distance level for lossy compression: target max butteraugli distance, lower = higher quality, 0 = lossless; range: 0 .. 25. Default is 1. IMWRITE_JPEGXL_EFFORT For JPEG XL, encoder effort/speed level without affecting decoding speed; it is between 1 (fastest) and 10 (slowest). Default is 7. IMWRITE_JPEGXL_QUALITY 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. IMWRITE_JPEG_CHROMA_QUALITY Separate chroma quality level, 0 - 100, default is -1 - don’t use. If JPEG_LIB_VERSION < 70, Not supported. IMWRITE_JPEG_LUMA_QUALITY Separate luma quality level, 0 - 100, default is -1 - don’t use. If JPEG_LIB_VERSION < 70, Not supported. IMWRITE_JPEG_OPTIMIZE Enable JPEG features, 0 or 1, default is False. IMWRITE_JPEG_PROGRESSIVE Enable JPEG features, 0 or 1, default is False. IMWRITE_JPEG_QUALITY For JPEG, it can be a quality from 0 to 100 (the higher is the better). Default value is 95. IMWRITE_JPEG_RST_INTERVAL JPEG restart interval, 0 - 65535, default is 0 - no restart. IMWRITE_JPEG_SAMPLING_FACTOR For JPEG, set sampling factor. See cv::ImwriteJPEGSamplingFactorParams. IMWRITE_JPEG_SAMPLING_FACTOR_411 4x1,1x1,1x1 IMWRITE_JPEG_SAMPLING_FACTOR_420 2x2,1x1,1x1(Default) IMWRITE_JPEG_SAMPLING_FACTOR_422 2x1,1x1,1x1 IMWRITE_JPEG_SAMPLING_FACTOR_440 1x2,1x1,1x1 IMWRITE_JPEG_SAMPLING_FACTOR_444 1x1,1x1,1x1(No subsampling) IMWRITE_PAM_FORMAT_BLACKANDWHITE IMWRITE_PAM_FORMAT_GRAYSCALE IMWRITE_PAM_FORMAT_GRAYSCALE_ALPHA IMWRITE_PAM_FORMAT_NULL IMWRITE_PAM_FORMAT_RGB IMWRITE_PAM_FORMAT_RGB_ALPHA IMWRITE_PAM_TUPLETYPE For PAM, sets the TUPLETYPE field to the corresponding string value that is defined for the format IMWRITE_PNG_BILEVEL Binary level PNG, 0 or 1, default is 0. IMWRITE_PNG_COMPRESSION 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). IMWRITE_PNG_STRATEGY One of cv::ImwritePNGFlags, default is IMWRITE_PNG_STRATEGY_RLE. IMWRITE_PNG_STRATEGY_DEFAULT Use this value for normal data. IMWRITE_PNG_STRATEGY_FILTERED 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. IMWRITE_PNG_STRATEGY_FIXED Using this value prevents the use of dynamic Huffman codes, allowing for a simpler decoder for special applications. IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY Use this value to force Huffman encoding only (no string match). IMWRITE_PNG_STRATEGY_RLE Use this value to limit match distances to one (run-length encoding). IMWRITE_PXM_BINARY For PPM, PGM, or PBM, it can be a binary format flag, 0 or 1. Default value is 1. IMWRITE_TIFF_COMPRESSION 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. IMWRITE_TIFF_COMPRESSION_ADOBE_DEFLATE Deflate compression, as recognized by Adobe IMWRITE_TIFF_COMPRESSION_CCITTFAX3 CCITT Group 3 fax encoding IMWRITE_TIFF_COMPRESSION_CCITTFAX4 CCITT Group 4 fax encoding IMWRITE_TIFF_COMPRESSION_CCITTRLE CCITT modified Huffman RLE IMWRITE_TIFF_COMPRESSION_CCITTRLEW [1] w/ word alignment IMWRITE_TIFF_COMPRESSION_CCITT_T4 CCITT T.4 (TIFF 6 name) IMWRITE_TIFF_COMPRESSION_CCITT_T6 CCITT T.6 (TIFF 6 name) IMWRITE_TIFF_COMPRESSION_DCS Kodak DCS encoding IMWRITE_TIFF_COMPRESSION_DEFLATE Deflate compression, legacy tag IMWRITE_TIFF_COMPRESSION_IT8BL IT8 Binary line art IMWRITE_TIFF_COMPRESSION_IT8CTPAD IT8 CT w/padding IMWRITE_TIFF_COMPRESSION_IT8LW IT8 Linework RLE IMWRITE_TIFF_COMPRESSION_IT8MP IT8 Monochrome picture IMWRITE_TIFF_COMPRESSION_JBIG ISO JBIG IMWRITE_TIFF_COMPRESSION_JP2000 Leadtools JPEG2000 IMWRITE_TIFF_COMPRESSION_JPEG %JPEG DCT compression IMWRITE_TIFF_COMPRESSION_JXL JPEGXL: WARNING not registered in Adobe-maintained registry IMWRITE_TIFF_COMPRESSION_LERC ESRI Lerc codec: https://github.com/Esri/lerc IMWRITE_TIFF_COMPRESSION_LZMA LZMA2 IMWRITE_TIFF_COMPRESSION_LZW Lempel-Ziv & Welch IMWRITE_TIFF_COMPRESSION_NEXT NeXT 2-bit RLE IMWRITE_TIFF_COMPRESSION_NONE dump mode IMWRITE_TIFF_COMPRESSION_OJPEG !6.0 JPEG IMWRITE_TIFF_COMPRESSION_PACKBITS Macintosh RLE IMWRITE_TIFF_COMPRESSION_PIXARFILM Pixar companded 10bit LZW IMWRITE_TIFF_COMPRESSION_PIXARLOG Pixar companded 11bit ZIP IMWRITE_TIFF_COMPRESSION_SGILOG SGI Log Luminance RLE IMWRITE_TIFF_COMPRESSION_SGILOG24 SGI Log 24-bit packed IMWRITE_TIFF_COMPRESSION_T43 !TIFF/FX T.43 colour by layered JBIG compression IMWRITE_TIFF_COMPRESSION_T85 !TIFF/FX T.85 JBIG compression IMWRITE_TIFF_COMPRESSION_THUNDERSCAN ThunderScan RLE IMWRITE_TIFF_COMPRESSION_WEBP WEBP: WARNING not registered in Adobe-maintained registry IMWRITE_TIFF_COMPRESSION_ZSTD ZSTD: WARNING not registered in Adobe-maintained registry IMWRITE_TIFF_PREDICTOR For TIFF, use to specify predictor. See cv::ImwriteTiffPredictorFlags. IMWRITE_TIFF_PREDICTOR_FLOATINGPOINT floating point predictor IMWRITE_TIFF_PREDICTOR_HORIZONTAL horizontal differencing IMWRITE_TIFF_PREDICTOR_NONE no prediction scheme used IMWRITE_TIFF_RESUNIT For TIFF, use to specify which DPI resolution unit to set; see libtiff documentation for valid values IMWRITE_TIFF_ROWSPERSTRIP For TIFF, use to specify the number of rows per strip. IMWRITE_TIFF_XDPI For TIFF, use to specify the X direction DPI IMWRITE_TIFF_YDPI For TIFF, use to specify the Y direction DPI IMWRITE_WEBP_QUALITY 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. AnimationTrait Mutable methods for crate::imgcodecs::Animation AnimationTraitConst Constant methods for crate::imgcodecs::Animation ImageCollectionTrait Mutable methods for crate::imgcodecs::ImageCollection ImageCollectionTraitConst Constant methods for crate::imgcodecs::ImageCollection ImageCollection_iteratorTrait Mutable methods for crate::imgcodecs::ImageCollection_iterator ImageCollection_iteratorTraitConst Constant methods for crate::imgcodecs::ImageCollection_iterator have_image_reader Checks if the specified image file can be decoded by OpenCV. have_image_writer Checks if the specified image file or specified file extension can be encoded by OpenCV. imcount Returns the number of images inside the given file imcount_def Returns the number of images inside the given file imdecode Reads an image from a buffer in memory. imdecode_to Reads an image from a buffer in memory. imdecodemulti Reads a multi-page image from a buffer in memory. imdecodemulti_def Reads a multi-page image from a buffer in memory. imencode Encodes an image into a memory buffer. imencode_def Encodes an image into a memory buffer. imencodemulti Encodes array of images into a memory buffer. imencodemulti_def Encodes array of images into a memory buffer. imread Loads an image from a file. imread_1 Loads an image from a file. imread_1_def Loads an image from a file. imread_def Loads an image from a file. imreadanimation Loads frames from an animated image file into an Animation structure. imreadanimation_def Loads frames from an animated image file into an Animation structure. imreadmulti Loads a multi-page image from a file. imreadmulti_def Loads a multi-page image from a file. imreadmulti_range Loads images of a multi-page image from a file. imreadmulti_range_def Loads images of a multi-page image from a file. imwrite Saves an image to a specified file. imwrite_def Saves an image to a specified file. imwriteanimation Saves an Animation to a specified file. imwriteanimation_def Saves an Animation to a specified file. imwritemulti multi-image overload for bindings imwritemulti_def multi-image overload for bindings