qt Qimage动态更改图片像素例子

#include "widget.h" #include "ui_widget.h" #include <QPainter> #include <QTimer> #include "QDebug" int i; Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget) { ui->setupUi(this); m_Image = QImage(200,200,QImage::Format_RGB32); QColor backColor = qRgb(255,255,0); //画布初始化背景色使用白色 m_Image.fill(backColor);//对画布进行填充 m_Image2.fill(QColor(255,255,255)); time = new QTimer(this); connect(time,SIGNAL(timeout()),this,SLOT(change())); for(int i = 0;i<=1301;++i) { m_vector.append(i); } } Widget::~Widget() { delete ui; } void Widget::on_pushButton_clicked() { time->start(500); } void Widget::change() { QRgb value; value = qRgb(255,0,0); for(int j =0;j<200;++j) { m_Image.setPixel(j,i,value); this->update(); } ++i; } //传入采样集合 acc 为取样精度 template <typename T> QVector<T> Widget::transf(QVector<T> &vector,const int acc) { QVector<T> newVec; newVec.reserve(vector.length()/acc); auto it = vector.begin(); for (it ; vector.end()-it >acc; it+=acc) { auto max = std::max_element(it, it+acc); newVec.push_back(*max); } return newVec; } void Widget::paintEvent(QPaintEvent *event) { QPainter painter(this); painter.drawImage(0,0,m_Image); painter.drawImage(250,0,m_Image2); } void Widget::on_pushButton_2_clicked() { time->stop(); qDebug()<<transf(m_vector,4); } void Widget::on_pushButton_3_clicked() { m_Image2 = m_Image; update(); for(int i =0;i<200;++i) { arr[i] = 0.523*i; qDebug()<<arr[i]; } qDebug()<<"转换了"; QVector<float> vec= charToVect(arr); qDebug()<<vec; } template <typename T> QVector<T> Widget::charToVect(T* arr) { for(int i; i<200; ++i) { m_vectorf.append(arr[i]); } qDebug()<<m_vectorf.length(); return m_vectorf; }