Imgcodecs (JavaCPP Presets for OpenCV 4.9.0-1.5.10 API)

java.lang.Object
- org.opencv.imgcodecs.Imgcodecs

```
public class Imgcodecs
extends Object
```

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`IMREAD_ANYCOLOR`
`static int`	`IMREAD_ANYDEPTH`
`static int`	`IMREAD_COLOR`
`static int`	`IMREAD_GRAYSCALE`
`static int`	`IMREAD_IGNORE_ORIENTATION`
`static int`	`IMREAD_LOAD_GDAL`
`static int`	`IMREAD_REDUCED_COLOR_2`
`static int`	`IMREAD_REDUCED_COLOR_4`
`static int`	`IMREAD_REDUCED_COLOR_8`
`static int`	`IMREAD_REDUCED_GRAYSCALE_2`
`static int`	`IMREAD_REDUCED_GRAYSCALE_4`
`static int`	`IMREAD_REDUCED_GRAYSCALE_8`
`static int`	`IMREAD_UNCHANGED`
`static int`	`IMWRITE_AVIF_DEPTH`
`static int`	`IMWRITE_AVIF_QUALITY`
`static int`	`IMWRITE_AVIF_SPEED`
`static int`	`IMWRITE_EXR_COMPRESSION`
`static int`	`IMWRITE_EXR_COMPRESSION_B44`
`static int`	`IMWRITE_EXR_COMPRESSION_B44A`
`static int`	`IMWRITE_EXR_COMPRESSION_DWAA`
`static int`	`IMWRITE_EXR_COMPRESSION_DWAB`
`static int`	`IMWRITE_EXR_COMPRESSION_NO`
`static int`	`IMWRITE_EXR_COMPRESSION_PIZ`
`static int`	`IMWRITE_EXR_COMPRESSION_PXR24`
`static int`	`IMWRITE_EXR_COMPRESSION_RLE`
`static int`	`IMWRITE_EXR_COMPRESSION_ZIP`
`static int`	`IMWRITE_EXR_COMPRESSION_ZIPS`
`static int`	`IMWRITE_EXR_DWA_COMPRESSION_LEVEL`
`static int`	`IMWRITE_EXR_TYPE`
`static int`	`IMWRITE_EXR_TYPE_FLOAT`
`static int`	`IMWRITE_EXR_TYPE_HALF`
`static int`	`IMWRITE_HDR_COMPRESSION`
`static int`	`IMWRITE_HDR_COMPRESSION_NONE`
`static int`	`IMWRITE_HDR_COMPRESSION_RLE`
`static int`	`IMWRITE_JPEG_CHROMA_QUALITY`
`static int`	`IMWRITE_JPEG_LUMA_QUALITY`
`static int`	`IMWRITE_JPEG_OPTIMIZE`
`static int`	`IMWRITE_JPEG_PROGRESSIVE`
`static int`	`IMWRITE_JPEG_QUALITY`
`static int`	`IMWRITE_JPEG_RST_INTERVAL`
`static int`	`IMWRITE_JPEG_SAMPLING_FACTOR`
`static int`	`IMWRITE_JPEG_SAMPLING_FACTOR_411`
`static int`	`IMWRITE_JPEG_SAMPLING_FACTOR_420`
`static int`	`IMWRITE_JPEG_SAMPLING_FACTOR_422`
`static int`	`IMWRITE_JPEG_SAMPLING_FACTOR_440`
`static int`	`IMWRITE_JPEG_SAMPLING_FACTOR_444`
`static int`	`IMWRITE_JPEG2000_COMPRESSION_X1000`
`static int`	`IMWRITE_PAM_FORMAT_BLACKANDWHITE`
`static int`	`IMWRITE_PAM_FORMAT_GRAYSCALE`
`static int`	`IMWRITE_PAM_FORMAT_GRAYSCALE_ALPHA`
`static int`	`IMWRITE_PAM_FORMAT_NULL`
`static int`	`IMWRITE_PAM_FORMAT_RGB`
`static int`	`IMWRITE_PAM_FORMAT_RGB_ALPHA`
`static int`	`IMWRITE_PAM_TUPLETYPE`
`static int`	`IMWRITE_PNG_BILEVEL`
`static int`	`IMWRITE_PNG_COMPRESSION`
`static int`	`IMWRITE_PNG_STRATEGY`
`static int`	`IMWRITE_PNG_STRATEGY_DEFAULT`
`static int`	`IMWRITE_PNG_STRATEGY_FILTERED`
`static int`	`IMWRITE_PNG_STRATEGY_FIXED`
`static int`	`IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY`
`static int`	`IMWRITE_PNG_STRATEGY_RLE`
`static int`	`IMWRITE_PXM_BINARY`
`static int`	`IMWRITE_TIFF_COMPRESSION`
`static int`	`IMWRITE_TIFF_RESUNIT`
`static int`	`IMWRITE_TIFF_XDPI`
`static int`	`IMWRITE_TIFF_YDPI`
`static int`	`IMWRITE_WEBP_QUALITY`

Constructor Summary

Constructors
Constructor and Description

Imgcodecs()

Constructors
Constructor and Description
`Imgcodecs()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static boolean`	`haveImageReader(String filename)` Returns true if the specified image can be decoded by OpenCV
`static boolean`	`haveImageWriter(String filename)` Returns true if an image with the specified filename can be encoded by OpenCV
`static long`	`imcount(String filename)` Returns the number of images inside the give file The function imcount will return the number of pages in a multi-page image, or 1 for single-page images
`static long`	`imcount(String filename, int flags)` Returns the number of images inside the give file The function imcount will return the number of pages in a multi-page image, or 1 for single-page images
`static Mat`	`imdecode(Mat buf, int flags)` Reads an image from a buffer in memory.
`static boolean`	`imdecodemulti(Mat buf, int flags, List<Mat> mats)` Reads a multi-page image from a buffer in memory.
`static boolean`	`imdecodemulti(Mat buf, int flags, List<Mat> mats, Range range)` Reads a multi-page image from a buffer in memory.
`static boolean`	`imencode(String ext, Mat img, MatOfByte buf)` Encodes an image into a memory buffer.
`static boolean`	`imencode(String ext, Mat img, MatOfByte buf, MatOfInt params)` Encodes an image into a memory buffer.
`static Mat`	`imread(String filename)` Loads an image from a file.
`static Mat`	`imread(String filename, int flags)` Loads an image from a file.
`static boolean`	`imreadmulti(String filename, List<Mat> mats)` Loads a multi-page image from a file.
`static boolean`	`imreadmulti(String filename, List<Mat> mats, int flags)` Loads a multi-page image from a file.
`static boolean`	`imreadmulti(String filename, List<Mat> mats, int start, int count)` Loads a of images of a multi-page image from a file.
`static boolean`	`imreadmulti(String filename, List<Mat> mats, int start, int count, int flags)` Loads a of images of a multi-page image from a file.
`static boolean`	`imwrite(String filename, Mat img)` Saves an image to a specified file.
`static boolean`	`imwrite(String filename, Mat img, MatOfInt params)` Saves an image to a specified file.
`static boolean`	`imwritemulti(String filename, List<Mat> img)`
`static boolean`	`imwritemulti(String filename, List<Mat> img, MatOfInt params)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - IMREAD_UNCHANGED
```
public static final int IMREAD_UNCHANGED
```
    See Also:
    
    Constant Field Values
  - IMREAD_GRAYSCALE
```
public static final int IMREAD_GRAYSCALE
```
    See Also:
    
    Constant Field Values
  - IMREAD_COLOR
```
public static final int IMREAD_COLOR
```
    See Also:
    
    Constant Field Values
  - IMREAD_ANYDEPTH
```
public static final int IMREAD_ANYDEPTH
```
    See Also:
    
    Constant Field Values
  - IMREAD_ANYCOLOR
```
public static final int IMREAD_ANYCOLOR
```
    See Also:
    
    Constant Field Values
  - IMREAD_LOAD_GDAL
```
public static final int IMREAD_LOAD_GDAL
```
    See Also:
    
    Constant Field Values
  - IMREAD_REDUCED_GRAYSCALE_2
```
public static final int IMREAD_REDUCED_GRAYSCALE_2
```
    See Also:
    
    Constant Field Values
  - IMREAD_REDUCED_COLOR_2
```
public static final int IMREAD_REDUCED_COLOR_2
```
    See Also:
    
    Constant Field Values
  - IMREAD_REDUCED_GRAYSCALE_4
```
public static final int IMREAD_REDUCED_GRAYSCALE_4
```
    See Also:
    
    Constant Field Values
  - IMREAD_REDUCED_COLOR_4
```
public static final int IMREAD_REDUCED_COLOR_4
```
    See Also:
    
    Constant Field Values
  - IMREAD_REDUCED_GRAYSCALE_8
```
public static final int IMREAD_REDUCED_GRAYSCALE_8
```
    See Also:
    
    Constant Field Values
  - IMREAD_REDUCED_COLOR_8
```
public static final int IMREAD_REDUCED_COLOR_8
```
    See Also:
    
    Constant Field Values
  - IMREAD_IGNORE_ORIENTATION
```
public static final int IMREAD_IGNORE_ORIENTATION
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_NO
```
public static final int IMWRITE_EXR_COMPRESSION_NO
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_RLE
```
public static final int IMWRITE_EXR_COMPRESSION_RLE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_ZIPS
```
public static final int IMWRITE_EXR_COMPRESSION_ZIPS
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_ZIP
```
public static final int IMWRITE_EXR_COMPRESSION_ZIP
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_PIZ
```
public static final int IMWRITE_EXR_COMPRESSION_PIZ
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_PXR24
```
public static final int IMWRITE_EXR_COMPRESSION_PXR24
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_B44
```
public static final int IMWRITE_EXR_COMPRESSION_B44
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_B44A
```
public static final int IMWRITE_EXR_COMPRESSION_B44A
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_DWAA
```
public static final int IMWRITE_EXR_COMPRESSION_DWAA
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION_DWAB
```
public static final int IMWRITE_EXR_COMPRESSION_DWAB
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_TYPE_HALF
```
public static final int IMWRITE_EXR_TYPE_HALF
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_TYPE_FLOAT
```
public static final int IMWRITE_EXR_TYPE_FLOAT
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_QUALITY
```
public static final int IMWRITE_JPEG_QUALITY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_PROGRESSIVE
```
public static final int IMWRITE_JPEG_PROGRESSIVE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_OPTIMIZE
```
public static final int IMWRITE_JPEG_OPTIMIZE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_RST_INTERVAL
```
public static final int IMWRITE_JPEG_RST_INTERVAL
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_LUMA_QUALITY
```
public static final int IMWRITE_JPEG_LUMA_QUALITY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_CHROMA_QUALITY
```
public static final int IMWRITE_JPEG_CHROMA_QUALITY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_SAMPLING_FACTOR
```
public static final int IMWRITE_JPEG_SAMPLING_FACTOR
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_COMPRESSION
```
public static final int IMWRITE_PNG_COMPRESSION
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_STRATEGY
```
public static final int IMWRITE_PNG_STRATEGY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_BILEVEL
```
public static final int IMWRITE_PNG_BILEVEL
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PXM_BINARY
```
public static final int IMWRITE_PXM_BINARY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_TYPE
```
public static final int IMWRITE_EXR_TYPE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_COMPRESSION
```
public static final int IMWRITE_EXR_COMPRESSION
```
    See Also:
    
    Constant Field Values
  - IMWRITE_EXR_DWA_COMPRESSION_LEVEL
```
public static final int IMWRITE_EXR_DWA_COMPRESSION_LEVEL
```
    See Also:
    
    Constant Field Values
  - IMWRITE_WEBP_QUALITY
```
public static final int IMWRITE_WEBP_QUALITY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_HDR_COMPRESSION
```
public static final int IMWRITE_HDR_COMPRESSION
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PAM_TUPLETYPE
```
public static final int IMWRITE_PAM_TUPLETYPE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_TIFF_RESUNIT
```
public static final int IMWRITE_TIFF_RESUNIT
```
    See Also:
    
    Constant Field Values
  - IMWRITE_TIFF_XDPI
```
public static final int IMWRITE_TIFF_XDPI
```
    See Also:
    
    Constant Field Values
  - IMWRITE_TIFF_YDPI
```
public static final int IMWRITE_TIFF_YDPI
```
    See Also:
    
    Constant Field Values
  - IMWRITE_TIFF_COMPRESSION
```
public static final int IMWRITE_TIFF_COMPRESSION
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG2000_COMPRESSION_X1000
```
public static final int IMWRITE_JPEG2000_COMPRESSION_X1000
```
    See Also:
    
    Constant Field Values
  - IMWRITE_AVIF_QUALITY
```
public static final int IMWRITE_AVIF_QUALITY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_AVIF_DEPTH
```
public static final int IMWRITE_AVIF_DEPTH
```
    See Also:
    
    Constant Field Values
  - IMWRITE_AVIF_SPEED
```
public static final int IMWRITE_AVIF_SPEED
```
    See Also:
    
    Constant Field Values
  - IMWRITE_HDR_COMPRESSION_NONE
```
public static final int IMWRITE_HDR_COMPRESSION_NONE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_HDR_COMPRESSION_RLE
```
public static final int IMWRITE_HDR_COMPRESSION_RLE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_SAMPLING_FACTOR_411
```
public static final int IMWRITE_JPEG_SAMPLING_FACTOR_411
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_SAMPLING_FACTOR_420
```
public static final int IMWRITE_JPEG_SAMPLING_FACTOR_420
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_SAMPLING_FACTOR_422
```
public static final int IMWRITE_JPEG_SAMPLING_FACTOR_422
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_SAMPLING_FACTOR_440
```
public static final int IMWRITE_JPEG_SAMPLING_FACTOR_440
```
    See Also:
    
    Constant Field Values
  - IMWRITE_JPEG_SAMPLING_FACTOR_444
```
public static final int IMWRITE_JPEG_SAMPLING_FACTOR_444
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PAM_FORMAT_NULL
```
public static final int IMWRITE_PAM_FORMAT_NULL
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PAM_FORMAT_BLACKANDWHITE
```
public static final int IMWRITE_PAM_FORMAT_BLACKANDWHITE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PAM_FORMAT_GRAYSCALE
```
public static final int IMWRITE_PAM_FORMAT_GRAYSCALE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PAM_FORMAT_GRAYSCALE_ALPHA
```
public static final int IMWRITE_PAM_FORMAT_GRAYSCALE_ALPHA
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PAM_FORMAT_RGB
```
public static final int IMWRITE_PAM_FORMAT_RGB
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PAM_FORMAT_RGB_ALPHA
```
public static final int IMWRITE_PAM_FORMAT_RGB_ALPHA
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_STRATEGY_DEFAULT
```
public static final int IMWRITE_PNG_STRATEGY_DEFAULT
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_STRATEGY_FILTERED
```
public static final int IMWRITE_PNG_STRATEGY_FILTERED
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY
```
public static final int IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_STRATEGY_RLE
```
public static final int IMWRITE_PNG_STRATEGY_RLE
```
    See Also:
    
    Constant Field Values
  - IMWRITE_PNG_STRATEGY_FIXED
```
public static final int IMWRITE_PNG_STRATEGY_FIXED
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - Imgcodecs
```
public Imgcodecs()
```
- Method Detail
  - imread
```
public static Mat imread(String filename,
                         int flags)
```
    Loads an image from a file. imread The function imread loads an image from the specified file and returns it. If the image cannot be read (because of missing file, improper permissions, unsupported or invalid format), the function returns an empty matrix ( Mat::data==NULL ). Currently, the following file formats are supported:
    - Windows bitmaps - \*.bmp, \*.dib (always supported)
    - JPEG files - \*.jpeg, \*.jpg, \*.jpe (see the *Note* section)
    - JPEG 2000 files - \*.jp2 (see the *Note* section)
    - Portable Network Graphics - \*.png (see the *Note* section)
    - WebP - \*.webp (see the *Note* section)
    - AVIF - \*.avif (see the *Note* section)
    - Portable image format - \*.pbm, \*.pgm, \*.ppm \*.pxm, \*.pnm (always supported)
    - PFM files - \*.pfm (see the *Note* section)
    - Sun rasters - \*.sr, \*.ras (always supported)
    - TIFF files - \*.tiff, \*.tif (see the *Note* section)
    - OpenEXR Image files - \*.exr (see the *Note* section)
    - Radiance HDR - \*.hdr, \*.pic (always supported)
    - Raster and Vector geospatial data supported by GDAL (see the *Note* section)
    Note:
    - The function determines the type of an image by the content, not by the file extension.
    - In the case of color images, the decoded images will have the channels stored in B G R order.
    - When using IMREAD_GRAYSCALE, the codec's internal grayscale conversion will be used, if available. Results may differ to the output of cvtColor()
    - On Microsoft Windows\* OS and MacOSX\*, the codecs shipped with an OpenCV image (libjpeg, libpng, libtiff, and libjasper) are used by default. So, OpenCV can always read JPEGs, PNGs, and TIFFs. On MacOSX, there is also an option to use native MacOSX image readers. But beware that currently these native image loaders give images with different pixel values because of the color management embedded into MacOSX.
    - On Linux\*, BSD flavors and other Unix-like open-source operating systems, OpenCV looks for codecs supplied with an OS image. Install the relevant packages (do not forget the development files, for example, "libjpeg-dev", in Debian\* and Ubuntu\*) to get the codec support or turn on the OPENCV_BUILD_3RDPARTY_LIBS flag in CMake.
    - In the case you set *WITH_GDAL* flag to true in CMake and REF: IMREAD_LOAD_GDAL to load the image, then the [GDAL](http://www.gdal.org) driver will be used in order to decode the image, supporting the following formats: [Raster](http://www.gdal.org/formats_list.html), [Vector](http://www.gdal.org/ogr_formats.html).
    - If EXIF information is embedded in the image file, the EXIF orientation will be taken into account and thus the image will be rotated accordingly except if the flags REF: IMREAD_IGNORE_ORIENTATION or REF: IMREAD_UNCHANGED are passed.
    - Use the IMREAD_UNCHANGED flag to keep the floating point values from PFM image.
    - By default number of pixels must be less than 2^30. Limit can be set using system variable OPENCV_IO_MAX_IMAGE_PIXELS
    Parameters:
    
    filename - Name of file to be loaded.
    
    flags - Flag that can take values of cv::ImreadModes
    
    Returns:
    
    automatically generated
  - imread
```
public static Mat imread(String filename)
```
    Loads an image from a file. imread The function imread loads an image from the specified file and returns it. If the image cannot be read (because of missing file, improper permissions, unsupported or invalid format), the function returns an empty matrix ( Mat::data==NULL ). Currently, the following file formats are supported:
    - Windows bitmaps - \*.bmp, \*.dib (always supported)
    - JPEG files - \*.jpeg, \*.jpg, \*.jpe (see the *Note* section)
    - JPEG 2000 files - \*.jp2 (see the *Note* section)
    - Portable Network Graphics - \*.png (see the *Note* section)
    - WebP - \*.webp (see the *Note* section)
    - AVIF - \*.avif (see the *Note* section)
    - Portable image format - \*.pbm, \*.pgm, \*.ppm \*.pxm, \*.pnm (always supported)
    - PFM files - \*.pfm (see the *Note* section)
    - Sun rasters - \*.sr, \*.ras (always supported)
    - TIFF files - \*.tiff, \*.tif (see the *Note* section)
    - OpenEXR Image files - \*.exr (see the *Note* section)
    - Radiance HDR - \*.hdr, \*.pic (always supported)
    - Raster and Vector geospatial data supported by GDAL (see the *Note* section)
    Note:
    - The function determines the type of an image by the content, not by the file extension.
    - In the case of color images, the decoded images will have the channels stored in B G R order.
    - When using IMREAD_GRAYSCALE, the codec's internal grayscale conversion will be used, if available. Results may differ to the output of cvtColor()
    - On Microsoft Windows\* OS and MacOSX\*, the codecs shipped with an OpenCV image (libjpeg, libpng, libtiff, and libjasper) are used by default. So, OpenCV can always read JPEGs, PNGs, and TIFFs. On MacOSX, there is also an option to use native MacOSX image readers. But beware that currently these native image loaders give images with different pixel values because of the color management embedded into MacOSX.
    - On Linux\*, BSD flavors and other Unix-like open-source operating systems, OpenCV looks for codecs supplied with an OS image. Install the relevant packages (do not forget the development files, for example, "libjpeg-dev", in Debian\* and Ubuntu\*) to get the codec support or turn on the OPENCV_BUILD_3RDPARTY_LIBS flag in CMake.
    - In the case you set *WITH_GDAL* flag to true in CMake and REF: IMREAD_LOAD_GDAL to load the image, then the [GDAL](http://www.gdal.org) driver will be used in order to decode the image, supporting the following formats: [Raster](http://www.gdal.org/formats_list.html), [Vector](http://www.gdal.org/ogr_formats.html).
    - If EXIF information is embedded in the image file, the EXIF orientation will be taken into account and thus the image will be rotated accordingly except if the flags REF: IMREAD_IGNORE_ORIENTATION or REF: IMREAD_UNCHANGED are passed.
    - Use the IMREAD_UNCHANGED flag to keep the floating point values from PFM image.
    - By default number of pixels must be less than 2^30. Limit can be set using system variable OPENCV_IO_MAX_IMAGE_PIXELS
    Parameters:
    
    filename - Name of file to be loaded.
    
    Returns:
    
    automatically generated
  - imreadmulti
```
public static boolean imreadmulti(String filename,
                                  List<Mat> mats,
                                  int flags)
```
    Loads a multi-page image from a file. The function imreadmulti loads a multi-page image from the specified file into a vector of Mat objects.
    
    Parameters:
    
    filename - Name of file to be loaded.
    
    mats - A vector of Mat objects holding each page.
    
    flags - Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR. SEE: cv::imread
    
    Returns:
    
    automatically generated
  - imreadmulti
```
public static boolean imreadmulti(String filename,
                                  List<Mat> mats)
```
    Loads a multi-page image from a file. The function imreadmulti loads a multi-page image from the specified file into a vector of Mat objects.
    
    Parameters:
    
    filename - Name of file to be loaded.
    
    mats - A vector of Mat objects holding each page. SEE: cv::imread
    
    Returns:
    
    automatically generated
  - imreadmulti
```
public static boolean imreadmulti(String filename,
                                  List<Mat> mats,
                                  int start,
                                  int count,
                                  int flags)
```
    Loads a of images of a multi-page image from a file. The function imreadmulti loads a specified range from a multi-page image from the specified file into a vector of Mat objects.
    
    Parameters:
    
    filename - Name of file to be loaded.
    
    mats - A vector of Mat objects holding each page.
    
    start - Start index of the image to load
    
    count - Count number of images to load
    
    flags - Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR. SEE: cv::imread
    
    Returns:
    
    automatically generated
  - imreadmulti
```
public static boolean imreadmulti(String filename,
                                  List<Mat> mats,
                                  int start,
                                  int count)
```
    Loads a of images of a multi-page image from a file. The function imreadmulti loads a specified range from a multi-page image from the specified file into a vector of Mat objects.
    
    Parameters:
    
    filename - Name of file to be loaded.
    
    mats - A vector of Mat objects holding each page.
    
    start - Start index of the image to load
    
    count - Count number of images to load SEE: cv::imread
    
    Returns:
    
    automatically generated
  - imcount
```
public static long imcount(String filename,
                           int flags)
```
    Returns the number of images inside the give file The function imcount will return the number of pages in a multi-page image, or 1 for single-page images
    
    Parameters:
    
    filename - Name of file to be loaded.
    
    flags - Flag that can take values of cv::ImreadModes, default with cv::IMREAD_ANYCOLOR.
    
    Returns:
    
    automatically generated
  - imcount
```
public static long imcount(String filename)
```
    Returns the number of images inside the give file The function imcount will return the number of pages in a multi-page image, or 1 for single-page images
    
    Parameters:
    
    filename - Name of file to be loaded.
    
    Returns:
    
    automatically generated
  - imwrite
```
public static boolean imwrite(String filename,
                              Mat img,
                              MatOfInt params)
```
    Saves an image to a specified file. The function imwrite saves the image to the specified file. The image format is chosen based on the filename extension (see cv::imread for the list of extensions). In general, only 8-bit unsigned (CV_8U) single-channel or 3-channel (with 'BGR' channel order) images can be saved using this function, with these exceptions:
    - With OpenEXR encoder, only 32-bit float (CV_32F) images can be saved.
      
      8-bit unsigned (CV_8U) images are not supported.
    - With Radiance HDR encoder, non 64-bit float (CV_64F) images can be saved.
      
      All images will be converted to 32-bit float (CV_32F).
    - With JPEG 2000 encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
    - With PAM encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
    - With PNG encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
      
      PNG images with an alpha channel can be saved using this function. To do this, create 8-bit (or 16-bit) 4-channel image BGRA, where the alpha channel goes last. Fully transparent pixels should have alpha set to 0, fully opaque pixels should have alpha set to 255/65535 (see the code sample below).
    - With PGM/PPM encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
    - With TIFF encoder, 8-bit unsigned (CV_8U), 16-bit unsigned (CV_16U), 32-bit float (CV_32F) and 64-bit float (CV_64F) images can be saved.
      
      Multiple images (vector of Mat) can be saved in TIFF format (see the code sample below).
      
      32-bit float 3-channel (CV_32FC3) TIFF images will be saved using the LogLuv high dynamic range encoding (4 bytes per pixel)
      
      If the image format is not supported, the image will be converted to 8-bit unsigned (CV_8U) and saved that way.
    If the format, depth or channel order is different, use Mat::convertTo and cv::cvtColor to convert it before saving. Or, use the universal FileStorage I/O functions to save the image to XML or YAML format. The sample below shows how to create a BGRA image, how to set custom compression parameters and save it to a PNG file. It also demonstrates how to save multiple images in a TIFF file: INCLUDE: snippets/imgcodecs_imwrite.cpp
    Parameters:
    
    filename - Name of the file.
    
    img - (Mat or vector of Mat) Image or Images to be saved.
    
    params - Format-specific parameters encoded as pairs (paramId_1, paramValue_1, paramId_2, paramValue_2, ... .) see cv::ImwriteFlags
    
    Returns:
    
    automatically generated
  - imwrite
```
public static boolean imwrite(String filename,
                              Mat img)
```
    Saves an image to a specified file. The function imwrite saves the image to the specified file. The image format is chosen based on the filename extension (see cv::imread for the list of extensions). In general, only 8-bit unsigned (CV_8U) single-channel or 3-channel (with 'BGR' channel order) images can be saved using this function, with these exceptions:
    - With OpenEXR encoder, only 32-bit float (CV_32F) images can be saved.
      
      8-bit unsigned (CV_8U) images are not supported.
    - With Radiance HDR encoder, non 64-bit float (CV_64F) images can be saved.
      
      All images will be converted to 32-bit float (CV_32F).
    - With JPEG 2000 encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
    - With PAM encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
    - With PNG encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
      
      PNG images with an alpha channel can be saved using this function. To do this, create 8-bit (or 16-bit) 4-channel image BGRA, where the alpha channel goes last. Fully transparent pixels should have alpha set to 0, fully opaque pixels should have alpha set to 255/65535 (see the code sample below).
    - With PGM/PPM encoder, 8-bit unsigned (CV_8U) and 16-bit unsigned (CV_16U) images can be saved.
    - With TIFF encoder, 8-bit unsigned (CV_8U), 16-bit unsigned (CV_16U), 32-bit float (CV_32F) and 64-bit float (CV_64F) images can be saved.
      
      Multiple images (vector of Mat) can be saved in TIFF format (see the code sample below).
      
      32-bit float 3-channel (CV_32FC3) TIFF images will be saved using the LogLuv high dynamic range encoding (4 bytes per pixel)
      
      If the image format is not supported, the image will be converted to 8-bit unsigned (CV_8U) and saved that way.
    If the format, depth or channel order is different, use Mat::convertTo and cv::cvtColor to convert it before saving. Or, use the universal FileStorage I/O functions to save the image to XML or YAML format. The sample below shows how to create a BGRA image, how to set custom compression parameters and save it to a PNG file. It also demonstrates how to save multiple images in a TIFF file: INCLUDE: snippets/imgcodecs_imwrite.cpp
    Parameters:
    
    filename - Name of the file.
    
    img - (Mat or vector of Mat) Image or Images to be saved.
    
    Returns:
    
    automatically generated
  - imwritemulti
```
public static boolean imwritemulti(String filename,
                                   List<Mat> img,
                                   MatOfInt params)
```
  - imwritemulti
```
public static boolean imwritemulti(String filename,
                                   List<Mat> img)
```
  - imdecode
```
public static Mat imdecode(Mat buf,
                           int flags)
```
    Reads an image from a buffer in memory. The function imdecode reads an image from the specified buffer in the memory. If the buffer is too short or contains invalid data, the function returns an empty matrix ( Mat::data==NULL ). See cv::imread for the list of supported formats and flags description. Note: In the case of color images, the decoded images will have the channels stored in B G R order.
    
    Parameters:
    
    buf - Input array or vector of bytes.
    
    flags - The same flags as in cv::imread, see cv::ImreadModes.
    
    Returns:
    
    automatically generated
  - imdecodemulti
```
public static boolean imdecodemulti(Mat buf,
                                    int flags,
                                    List<Mat> mats,
                                    Range range)
```
    Reads a multi-page image from a buffer in memory. The function imdecodemulti reads a multi-page image from the specified buffer in the memory. If the buffer is too short or contains invalid data, the function returns false. See cv::imreadmulti for the list of supported formats and flags description. Note: In the case of color images, the decoded images will have the channels stored in B G R order.
    
    Parameters:
    
    buf - Input array or vector of bytes.
    
    flags - The same flags as in cv::imread, see cv::ImreadModes.
    
    mats - A vector of Mat objects holding each page, if more than one.
    
    range - A continuous selection of pages.
    
    Returns:
    
    automatically generated
  - imdecodemulti
```
public static boolean imdecodemulti(Mat buf,
                                    int flags,
                                    List<Mat> mats)
```
    Reads a multi-page image from a buffer in memory. The function imdecodemulti reads a multi-page image from the specified buffer in the memory. If the buffer is too short or contains invalid data, the function returns false. See cv::imreadmulti for the list of supported formats and flags description. Note: In the case of color images, the decoded images will have the channels stored in B G R order.
    
    Parameters:
    
    buf - Input array or vector of bytes.
    
    flags - The same flags as in cv::imread, see cv::ImreadModes.
    
    mats - A vector of Mat objects holding each page, if more than one.
    
    Returns:
    
    automatically generated
  - imencode
```
public static boolean imencode(String ext,
                               Mat img,
                               MatOfByte buf,
                               MatOfInt params)
```
    Encodes an image into a memory buffer. The function imencode compresses the image and stores it in the memory buffer that is resized to fit the result. See cv::imwrite for the list of supported formats and flags description.
    
    Parameters:
    
    ext - File extension that defines the output format. Must include a leading period.
    
    img - Image to be written.
    
    buf - Output buffer resized to fit the compressed image.
    
    params - Format-specific parameters. See cv::imwrite and cv::ImwriteFlags.
    
    Returns:
    
    automatically generated
  - imencode
```
public static boolean imencode(String ext,
                               Mat img,
                               MatOfByte buf)
```
    Encodes an image into a memory buffer. The function imencode compresses the image and stores it in the memory buffer that is resized to fit the result. See cv::imwrite for the list of supported formats and flags description.
    
    Parameters:
    
    ext - File extension that defines the output format. Must include a leading period.
    
    img - Image to be written.
    
    buf - Output buffer resized to fit the compressed image.
    
    Returns:
    
    automatically generated
  - haveImageReader
```
public static boolean haveImageReader(String filename)
```
    Returns true if the specified image can be decoded by OpenCV
    
    Parameters:
    
    filename - File name of the image
    
    Returns:
    
    automatically generated
  - haveImageWriter
```
public static boolean haveImageWriter(String filename)
```
    Returns true if an image with the specified filename can be encoded by OpenCV
    
    Parameters:
    
    filename - File name of the image
    
    Returns:
    
    automatically generated

Class Imgcodecs

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

IMREAD_UNCHANGED

IMREAD_GRAYSCALE

IMREAD_COLOR

IMREAD_ANYDEPTH

IMREAD_ANYCOLOR

IMREAD_LOAD_GDAL

IMREAD_REDUCED_GRAYSCALE_2

IMREAD_REDUCED_COLOR_2

IMREAD_REDUCED_GRAYSCALE_4

IMREAD_REDUCED_COLOR_4

IMREAD_REDUCED_GRAYSCALE_8

IMREAD_REDUCED_COLOR_8

IMREAD_IGNORE_ORIENTATION

IMWRITE_EXR_COMPRESSION_NO

IMWRITE_EXR_COMPRESSION_RLE

IMWRITE_EXR_COMPRESSION_ZIPS

IMWRITE_EXR_COMPRESSION_ZIP

IMWRITE_EXR_COMPRESSION_PIZ

IMWRITE_EXR_COMPRESSION_PXR24

IMWRITE_EXR_COMPRESSION_B44

IMWRITE_EXR_COMPRESSION_B44A

IMWRITE_EXR_COMPRESSION_DWAA

IMWRITE_EXR_COMPRESSION_DWAB

IMWRITE_EXR_TYPE_HALF

IMWRITE_EXR_TYPE_FLOAT

IMWRITE_JPEG_QUALITY

IMWRITE_JPEG_PROGRESSIVE

IMWRITE_JPEG_OPTIMIZE

IMWRITE_JPEG_RST_INTERVAL

IMWRITE_JPEG_LUMA_QUALITY

IMWRITE_JPEG_CHROMA_QUALITY

IMWRITE_JPEG_SAMPLING_FACTOR

IMWRITE_PNG_COMPRESSION

IMWRITE_PNG_STRATEGY

IMWRITE_PNG_BILEVEL

IMWRITE_PXM_BINARY

IMWRITE_EXR_TYPE

IMWRITE_EXR_COMPRESSION

IMWRITE_EXR_DWA_COMPRESSION_LEVEL

IMWRITE_WEBP_QUALITY

IMWRITE_HDR_COMPRESSION

IMWRITE_PAM_TUPLETYPE

IMWRITE_TIFF_RESUNIT

IMWRITE_TIFF_XDPI

IMWRITE_TIFF_YDPI

IMWRITE_TIFF_COMPRESSION

IMWRITE_JPEG2000_COMPRESSION_X1000

IMWRITE_AVIF_QUALITY

IMWRITE_AVIF_DEPTH

IMWRITE_AVIF_SPEED

IMWRITE_HDR_COMPRESSION_NONE

IMWRITE_HDR_COMPRESSION_RLE

IMWRITE_JPEG_SAMPLING_FACTOR_411

IMWRITE_JPEG_SAMPLING_FACTOR_420

IMWRITE_JPEG_SAMPLING_FACTOR_422

IMWRITE_JPEG_SAMPLING_FACTOR_440

IMWRITE_JPEG_SAMPLING_FACTOR_444

IMWRITE_PAM_FORMAT_NULL

IMWRITE_PAM_FORMAT_BLACKANDWHITE

IMWRITE_PAM_FORMAT_GRAYSCALE

IMWRITE_PAM_FORMAT_GRAYSCALE_ALPHA

IMWRITE_PAM_FORMAT_RGB

IMWRITE_PAM_FORMAT_RGB_ALPHA

IMWRITE_PNG_STRATEGY_DEFAULT

IMWRITE_PNG_STRATEGY_FILTERED

IMWRITE_PNG_STRATEGY_HUFFMAN_ONLY

IMWRITE_PNG_STRATEGY_RLE

IMWRITE_PNG_STRATEGY_FIXED

Constructor Detail

Imgcodecs

Method Detail

imread

imread

imreadmulti