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Merge pull request #26152 from sturkmen72:m_buf_supported

Documentation update for imagecodecs #26152

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake
This commit is contained in:
Suleyman TURKMEN
2024-09-17 09:34:38 +03:00
committed by GitHub
parent e043d5d9d6
commit f503890c2b
7 changed files with 254 additions and 249 deletions
+24 -25
View File
@@ -222,9 +222,9 @@ enum ImwriteHDRCompressionFlags {
@anchor 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 ).
The `imread` function loads an image from the specified file and returns OpenCV matrix. If the image cannot be
read (because of a missing file, improper permissions, or unsupported/invalid format), the function
returns an empty matrix.
Currently, the following file formats are supported:
@@ -234,7 +234,7 @@ Currently, the following file formats are supported:
- 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)
- 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)
@@ -243,32 +243,31 @@ Currently, the following file formats are 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.
- The function determines the type of an image by its 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
Results may differ from the output of cvtColor().
- On Microsoft Windows\* and Mac OS\*, the codecs shipped with OpenCV (libjpeg, libpng, libtiff,
and libjasper) are used by default. So, OpenCV can always read JPEGs, PNGs, and TIFFs. On Mac OS,
there is also an option to use native Mac OS image readers. However, beware that currently these
native image loaders give images with different pixel values because of the color management embedded
into Mac OS.
- On Linux\*, BSD flavors, and other Unix-like open-source operating systems, OpenCV looks for
codecs supplied with the OS. Ensure the relevant packages are installed (including development
files, such as "libjpeg-dev" in Debian\* and Ubuntu\*) to get 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
- If the *WITH_GDAL* flag is set to true in CMake and @ref IMREAD_LOAD_GDAL is used to load the image,
the [GDAL](http://www.gdal.org) driver will be used to decode the image, supporting
[Raster](http://www.gdal.org/formats_list.html) and [Vector](http://www.gdal.org/ogr_formats.html) formats.
- 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 unless 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
- Use the IMREAD_UNCHANGED flag to preserve the floating-point values from PFM images.
- By default, the number of pixels must be less than 2^30. This limit can be changed by setting
the environment variable `OPENCV_IO_MAX_IMAGE_PIXELS`. See @ref tutorial_env_reference.
@param filename Name of file to be loaded.
@param flags Flag that can take values of cv::ImreadModes
@param filename Name of the file to be loaded.
@param flags Flag that can take values of `cv::ImreadModes`.
*/
CV_EXPORTS_W Mat imread( const String& filename, int flags = IMREAD_COLOR_BGR );