File indexing completed on 2024-04-28 03:54:46 

0001 /*
0002     SPDX-FileCopyrightText: 2023 Mirco Miranda <mircomir@outlook.com>
0003 
0004     SPDX-License-Identifier: LGPL-2.0-or-later
0005 */
0006 
0007 #ifndef SCANLINECONVERTER_P_H
0008 #define SCANLINECONVERTER_P_H
0009 
0010 #include <QColorSpace>
0011 #include <QImage>
0012 
0013 /*!
0014  * \brief The scanlineFormatConversion class
0015  * A class to convert an image scan line. It introduces some overhead on small images
0016  * but performs better on large images. :)
0017  */
0018 class ScanLineConverter
0019 {
0020 public:
0021     ScanLineConverter(const QImage::Format &targetFormat);
0022     ScanLineConverter(const ScanLineConverter &other);
0023     ScanLineConverter &operator=(const ScanLineConverter &other);
0024 
0025     /*!
0026      * \brief targetFormat
0027      * \return The target format set in the constructor.
0028      */
0029     QImage::Format targetFormat() const;
0030 
0031     /*!
0032      * \brief setTargetColorSpace
0033      * Set the colorspace conversion.
0034      *
0035      * In addition to format conversion, it is also possible to convert the color
0036      * space if the source image has a different one set.
0037      * The conversion is done on the source format if and only if the image
0038      * has a color depth greater than 24 bit and the color profile set is different
0039      * from that of the image itself.
0040      * \param colorSpace
0041      */
0042     void setTargetColorSpace(const QColorSpace &colorSpace);
0043     QColorSpace targetColorSpace() const;
0044 
0045     /*!
0046      * \brief setDefaultSourceColorSpace
0047      * Set the source color space to use when the image does not have a color space.
0048      * \param colorSpace
0049      */
0050     void setDefaultSourceColorSpace(const QColorSpace &colorSpace);
0051     QColorSpace defaultSourceColorSpace() const;
0052 
0053     /*!
0054      * \brief convertedScanLine
0055      * Convert the scanline \a y.
0056      * \note If the image format (and color space) is the same of converted format, it returns the image scan line.
0057      * \return The scan line converted.
0058      */
0059     const uchar *convertedScanLine(const QImage &image, qint32 y);
0060 
0061     /*!
0062      * \brief bytesPerLine
0063      * \return The size of the last converted scanline.
0064      */
0065     qsizetype bytesPerLine() const;
0066 
0067     /*!
0068      * \brief isColorSpaceConversionNeeded
0069      * Calculates if a color space conversion is needed.
0070      * \note Only 24 bit or grater images.
0071      * \param image The source image.
0072      * \param targetColorSpace The target color space.
0073      * \param defaultColorSpace The default color space to use it image does not contains one.
0074      * \return True if the conversion should be done otherwise false.
0075      */
0076     static bool isColorSpaceConversionNeeded(const QImage &image, const QColorSpace &targetColorSpace, const QColorSpace &defaultColorSpace = QColorSpace());
0077 
0078     /*!
0079      * \brief isColorSpaceConversionNeeded
0080      */
0081     inline bool isColorSpaceConversionNeeded(const QImage &image) const
0082     {
0083         return isColorSpaceConversionNeeded(image, _colorSpace, _defaultColorSpace);
0084     }
0085 
0086 private:
0087     // data
0088     QImage::Format _targetFormat;
0089     QColorSpace _colorSpace;
0090     QColorSpace _defaultColorSpace;
0091 
0092     // internal buffers
0093     QImage _tmpBuffer;
0094     QImage _convBuffer;
0095 };
0096 
0097 #endif // SCANLINECONVERTER_P_H