mirror/yacreader
1
0
Fork 0
mirror of https://github.com/YACReader/yacreader synced 2025-06-04 01:28:55 -04:00
Code Issues Actions Packages Projects Releases Wiki Activity

Faster image processing

Browse Source
This commit is contained in:
Luis Ángel San Martín 2024-08-31 17:11:28 +02:00
parent b12e1212b5
commit 68bf76a8b2
1 changed files with 7 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
image_processing/resize_image.cpp
View File

@ -352,7 +352,6 @@ QVector<QRgb> processRow(int y, int targetWidth, int targetHeight, const QImage
#endif
// Main function to scale the image
QImage scaleImageLanczos(const QImage &sourceImage, int targetWidth, int targetHeight, int a = 3)
{
QImage targetImage(targetWidth, targetHeight, QImage::Format_ARGB32);
@ -362,24 +361,18 @@ QImage scaleImageLanczos(const QImage &sourceImage, int targetWidth, int targetH
rows[i] = i;
}
// Use a QVector to store the results of the processed rows
QVector<QVector<QRgb>> results(targetHeight);
uchar *imgBits = targetImage.bits();
int bytesPerLine = targetImage.bytesPerLine();
// Launch concurrent tasks using QtConcurrent::map, which modifies the container in place
QtConcurrent::blockingMap(rows, [&results, targetWidth, targetHeight, &sourceImage, a](int y) {
results[y] = processRow(y, targetWidth, targetHeight, sourceImage, a);
QtConcurrent::blockingMap(rows, [targetWidth, targetHeight, &sourceImage, a, imgBits, bytesPerLine](int y) {
QVector<QRgb> rowPixels = processRow(y, targetWidth, targetHeight, sourceImage, a);
uchar *rowPtr = imgBits + y * bytesPerLine;
std::memcpy(rowPtr, rowPixels.constData(), targetWidth * sizeof(QRgb));
});
// Set the pixels in the target image
for (int y = 0; y < targetHeight; ++y) {
const QVector<QRgb> &row = results[y];
for (int x = 0; x < targetWidth; ++x) {
targetImage.setPixel(x, y, row[x]);
}
}
return targetImage;
}
QPixmap scalePixmapLanczosQt(const QPixmap &pixmap, int targetWidth, int targetHeight, int a)
{
QImage sourceImage = pixmap.toImage();