OpenCV C++ imgdecode 在 OSX 上生成异常

OpenCV C++ imgdecode generating an exception on OSX

我有一个应用程序可以从相机拍摄照片、对其进行编码、执行一些操作然后对其进行解码。它适用于 Ubuntu,但在 OSX imgdecode 上生成以下异常:

libc++abi.dylib: terminating with uncaught exception of type cv::Exception: OpenCV(4.2.0) /tmp/opencv-20200404-3398-7w1b75/opencv-4.2.0/modules/imgcodecs/src/loadsave.cpp:732: error: (-215:Assertion failed) buf.checkVector(1, CV_8U) > 0 in function 'imdecode_'

Abort trap: 6

我尝试在同一个脚本中对图像进行编码和解码,以获得最小的可验证示例。脚本如下:

#include "opencv2/opencv.hpp"
#include<unistd.h>
using namespace std;
using namespace cv;

int main(int argc, char *argv[])
{
    Mat frame;
    VideoCapture cam(0);
    std::vector<uchar> buf_in;
    u_char *buf ;
    while(1)
    {
        cam>>frame;
        imencode(".png",frame, buf_in);
        //encode image and put data into the vector buf
        frame  = cv::imdecode(cv::Mat(3, buf_in.size(), CV_8UC3, buf_in.data()), 1);
        imshow("window", frame);
        waitKey(2);
    }
    return 0;

}

并且它仍在 OSX 上生成异常。这是为什么?为什么会产生异常?为什么只在 OSX 上?

POST 剧本

如果需要编译代码,可以使用下面的Makefile:

CXX = g++

CXXFLAGS = -std=c++11 -pg
INC_PATH = `pkg-config --cflags opencv4`

LIBS = `pkg-config --libs opencv4`

SOURCEDIR := ./
SOURCES := $(wildcard $(SOURCEDIR)/*.cpp)
OBJDIR=$(SOURCEDIR)/obj

OBJECTS := $(patsubst $(SOURCEDIR)/%.cpp,$(OBJDIR)/%.o, $(SOURCES))
DEPENDS := $(patsubst $(SOURCEDIR)/%.cpp,$(OBJDIR)/%.d,$(SOURCES))
WARNING := -Wall -Wextra

.PHONY: all clean

all: openCV

clean:
    $(RM) $(OBJECTS) $(DEPENDS) openCV

openCV: $(OBJECTS)
    $(CXX) $(WARNING) $(CXXFLAGS) $(INC_PATH) $^ -o $@ $(LIBS)

-include $(DEPENDS)

$(OBJDIR):
    mkdir -p $(OBJDIR)

$(OBJDIR)/%.o: $(SOURCEDIR)/%.cpp Makefile | $(OBJDIR)
    $(CXX) $(WARNING) $(CXXFLAGS) $(INC_PATH) -MMD -MP -c $< -o $@

我解决了将 imdecode 的参数更改为包含原始数据的 vector<u_char>,而不是初始化新的 Mat 结构。

#include "opencv2/opencv.hpp"
#include<unistd.h>
using namespace std;
using namespace cv;

int main(int argc, char *argv[])
{
    Mat frame;
    VideoCapture cam(0);
    std::vector<uchar> buf_in;
    u_char *buf ;
    while(1)
    {
        cam>>frame;
        imencode(".png",frame, buf_in);
        //encode image and put data into the vector buf
        buf_out.assign(buf_in.data, buf_in.data+buf_in.size());
        frame  = cv::imdecode(buf_out, 1);
        imshow("window", frame);
        waitKey(2);
    }
    return 0;

}