A width or height of zero would cause a malloc call with 0 bytes. Calling malloc with a size of 0 is implementation dependend and may return a non-null pointer which cannot be used but must be forwared to free.
Note: higher level runtime checks already prevent that encode_bmp_to_jpegls is called with these bad values.
The sample code would not read all bmp_dib_header fields. This has been corrected.
It is often the case that the horizontal and vertical resolution are not defined in a BMP file (set to zero).
Added also an extra check that the width and height info is correctly set in a BMP file, this to prevent that memory buffer of 0 bytes is allocated.
In the BMP file format every row is rounded up to a multiple of 4 bytes. The original sample code was unable to handle it. When using images with a special size (for example 403 * 100) this would cause incorrect converted images.
The C and C++ samples can convert a .bmp file to a .jls encoded file. These samples were missing essential steps to ensure the .jls images look the same as the original .bmp image. This has been corrected with:
- Pixels in a .bmp file are stored as Blue\Green\Red, JPEG-LS requires these to be in the format Red\Green\Blue
- The rows in a .bmp file are stored bottom up, JPEG-LS expects these files top down
- An additional command line parameter has been added to control which interleave mode to use
Enable clang-tidy for the MSBuild checked build configuration. The CharLSUnitTest project is excluded as clang-tidy is extreme slow for this project.
The warning clang-diagnostic-sign-conversion requires more planning before this warning can be global enabled.
Both the MSVC and the gcc\clang C++ compiler provide additional attributes that can be used to assist the static analyzer build into these compilers to detect problems at compile time.
The problem is that these extension attributes are not cross compiler compatible, which requires additional macros to ensure that all supported compiler can compile the code.
The main focus of adding these attributes is on the external C API as in that area the most errors can be made.
Address feedback from the SonarCloud static analyzer, replace strcpy with a safe implementation. As no cross platform solution is available, introduce a #ifdef/#else based solution.
Also get rid of _CRT_SECURE_NO_WARNINGS by removing a not used function and using std::ifstream instead of fopen\fclose.
"RAW" JPEG-LS headers miss crucial information like the color space and the resolution. Update the image to demonstrate how to encode this info in a JPEG-LS encoded image.
Apply the modern way of documenting the used license, by referencing a SPDX Unique License Identifier in the source code files.
Note: From the legal point of view, this commit is only a change to the textual representation of the license information, but in no way any change to the actual license terms. With this commit applied, all files will still be licensed under the same terms they were before.
The current C API prevents adding new features and the introduction of an object oriented C++ interface. Every change results directly in a ABI break. To prevent this a new C API is introduced that is easier to extend and to maintain. On top of this API are 2 C++ classes: jpeg_encoder and jpeg_decoder to encode and decode JPEG-LS files.
This commit comes also with the following changes:
- Updated .clang-format
- Switch to Visual Studio 2019 for the CI build pipeline
- Support for reading and writing SPIFF header
- Incomplete support for JFIF header has been removed
- Extended unit test coverage
Since C++11, it is possible to return rich error information. Replace the custom way of returning error values and strings with the C++ standard way.
The only limitation is that the strings need to fixed and cannot use parameters. This should be no limitation in practice.
Modern practice is to move the interface header files to a include/<lib-name> folder. This prevents that header filenames conflict with other libraries. And it also allows client code to use #include <package-name\header-filename.h> constructions.
