Merge pull request opencv#26152 from sturkmen72:m_buf_supported

Documentation update for imagecodecs opencv#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

Author: sturkmen72

modules/imgcodecs/include/opencv2/imgcodecs.hpp

@@ -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 );
 

modules/imgcodecs/src/bitstrm.cpp

@@ -1,44 +1,6 @@
-/*M///////////////////////////////////////////////////////////////////////////////////////
-//
-//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
-//
-//  By downloading, copying, installing or using the software you agree to this license.
-//  If you do not agree to this license, do not download, install,
-//  copy or use the software.
-//
-//
-//                           License Agreement
-//                For Open Source Computer Vision Library
-//
-// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
-// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
-// Third party copyrights are property of their respective owners.
-//
-// Redistribution and use in source and binary forms, with or without modification,
-// are permitted provided that the following conditions are met:
-//
-//   * Redistribution's of source code must retain the above copyright notice,
-//     this list of conditions and the following disclaimer.
-//
-//   * Redistribution's in binary form must reproduce the above copyright notice,
-//     this list of conditions and the following disclaimer in the documentation
-//     and/or other materials provided with the distribution.
-//
-//   * The name of the copyright holders may not be used to endorse or promote products
-//     derived from this software without specific prior written permission.
-//
-// This software is provided by the copyright holders and contributors "as is" and
-// any express or implied warranties, including, but not limited to, the implied
-// warranties of merchantability and fitness for a particular purpose are disclaimed.
-// In no event shall the Intel Corporation or contributors be liable for any direct,
-// indirect, incidental, special, exemplary, or consequential damages
-// (including, but not limited to, procurement of substitute goods or services;
-// loss of use, data, or profits; or business interruption) however caused
-// and on any theory of liability, whether in contract, strict liability,
-// or tort (including negligence or otherwise) arising in any way out of
-// the use of this software, even if advised of the possibility of such damage.
-//
-//M*/
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level
+// directory of this distribution and at http://opencv.org/license.html
 
 #include "precomp.hpp"
 #include "bitstrm.hpp"
@@ -49,11 +11,6 @@ namespace cv
 
 const int BS_DEF_BLOCK_SIZE = 1<<15;
 
-bool  bsIsBigEndian( void )
-{
-    return (((const int*)"\0\x1\x2\x3\x4\x5\x6\x7")[0] & 255) != 0;
-}
-
 /////////////////////////  RBaseStream ////////////////////////////
 
 bool  RBaseStream::isOpened()

modules/imgcodecs/src/bitstrm.hpp

@@ -1,44 +1,6 @@
-/*M///////////////////////////////////////////////////////////////////////////////////////
-//
-//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
-//
-//  By downloading, copying, installing or using the software you agree to this license.
-//  If you do not agree to this license, do not download, install,
-//  copy or use the software.
-//
-//
-//                           License Agreement
-//                For Open Source Computer Vision Library
-//
-// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
-// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
-// Third party copyrights are property of their respective owners.
-//
-// Redistribution and use in source and binary forms, with or without modification,
-// are permitted provided that the following conditions are met:
-//
-//   * Redistribution's of source code must retain the above copyright notice,
-//     this list of conditions and the following disclaimer.
-//
-//   * Redistribution's in binary form must reproduce the above copyright notice,
-//     this list of conditions and the following disclaimer in the documentation
-//     and/or other materials provided with the distribution.
-//
-//   * The name of the copyright holders may not be used to endorse or promote products
-//     derived from this software without specific prior written permission.
-//
-// This software is provided by the copyright holders and contributors "as is" and
-// any express or implied warranties, including, but not limited to, the implied
-// warranties of merchantability and fitness for a particular purpose are disclaimed.
-// In no event shall the Intel Corporation or contributors be liable for any direct,
-// indirect, incidental, special, exemplary, or consequential damages
-// (including, but not limited to, procurement of substitute goods or services;
-// loss of use, data, or profits; or business interruption) however caused
-// and on any theory of liability, whether in contract, strict liability,
-// or tort (including negligence or otherwise) arising in any way out of
-// the use of this software, even if advised of the possibility of such damage.
-//
-//M*/
+// This file is part of OpenCV project.
+// It is subject to the license terms in the LICENSE file found in the top-level
+// directory of this distribution and at http://opencv.org/license.html
 
 #ifndef _BITSTRM_H_
 #define _BITSTRM_H_
@@ -183,13 +145,6 @@ class WMByteStream : public WLByteStream
     bool putDWord( int val );
 };
 
-inline unsigned BSWAP(unsigned v)
-{
-    return (v<<24)|((v&0xff00)<<8)|((v>>8)&0xff00)|((unsigned)v>>24);
-}
-
-bool bsIsBigEndian( void );
-
 }
 
 #endif/*_BITSTRM_H_*/