fenix/PDF4QT
1
0
Fork 0
mirror of https://github.com/JakubMelka/PDF4QT.git synced 2025-06-05 21:59:17 +02:00
Code Issues Packages Projects Releases Wiki Activity

Optimization (multithreading)

Browse Source
This commit is contained in:
Jakub Melka
2021-02-13 17:09:57 +01:00
parent 14cd4c3dd0
commit f020098435
5 changed files with 211 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
Pdf4QtLib/sources/pdfcms.cpp
View File

@ -16,6 +16,7 @@
// along with Pdf4Qt. If not, see <https://www.gnu.org/licenses/>.
#include "pdfcms.h"
#include "pdfexecutionpolicy.h"
#include <QApplication>
#include <QReadWriteLock>
@ -329,7 +330,52 @@ bool PDFLittleCMS::transformColorSpace(const PDFCMS::ColorSpaceTransformParams&
inputPixelCount == outputPixelCount)
{
PDFColorBuffer outputBuffer = params.output;
cmsDoTransform(transform, inputColors, outputBuffer.begin(), inputPixelCount);
if (inputPixelCount > params.multithreadingThreshold)
{
struct TransformInfo
{
inline TransformInfo(const float* source, float* target, cmsUInt32Number pixelCount) :
source(source),
target(target),
pixelCount(pixelCount)
{
}
const float* source = nullptr;
float* target = nullptr;
cmsUInt32Number pixelCount = 0;
};
const cmsUInt32Number blockSize = 4096;
std::vector<TransformInfo> infos;
infos.reserve(inputPixelCount / blockSize + 1);
const float* sourcePointer = inputColors;
float* targetPointer = outputBuffer.begin();
cmsUInt32Number remainingPixelCount = inputPixelCount;
while (remainingPixelCount > 0)
{
const cmsUInt32Number currentPixelCount = qMin(blockSize, remainingPixelCount);
infos.emplace_back(sourcePointer, targetPointer, currentPixelCount);
sourcePointer += currentPixelCount * inputChannels;
targetPointer += currentPixelCount * outputChannels;
remainingPixelCount -= currentPixelCount;
}
auto processEntry = [transform](const TransformInfo& info)
{
cmsDoTransform(transform, info.source, info.target, info.pixelCount);
};
PDFExecutionPolicy::execute(PDFExecutionPolicy::Scope::Content, infos.begin(), infos.end(), processEntry);
}
else
{
// Single-threaded transform
cmsDoTransform(transform, inputColors, outputBuffer.begin(), inputPixelCount);
}
if (isOutputCMYK)
{