cv::Mat to Magick::Image => Q8 C++ API x64 Windows VS2017

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Frs
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Joined: 2019-01-16T11:47:47-07:00
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cv::Mat to Magick::Image => Q8 C++ API x64 Windows VS2017

Post by Frs » 2019-01-16T11:56:21-07:00

Helllo,
I asked yesterday on stackoverflow about an issue i face in converting an image from cv::Mat to Magick::Image.
The final aim is to save multiple page tiff file.
The original post is there : https://stackoverflow.com/questions/542 ... age-cv-uc3

Code: Select all

TiffWriter::TiffWriter(std::string filename) : filename(filename) {}

// for example for a 8 bit gray image buffer
void TiffWriter::writeGray(const unsigned char* buffer, int width, int height)
{
    Magick::Blob gray8Blob(buffer, width * height);
    Magick::Geometry size(width, height);
    Magick::Image gray8Image(gray8Blob, size, 8, "GRAY");
    imageList.push_back(gray8Image);
}
void TiffWriter::writeRGB(Mat& mat)
{
    auto depth = mat.depth();
    auto channels = mat.channels();
    auto type = mat.type();
    Magick::Image Mg_RGB(mat.cols,mat.rows,"BGR",Magick::CharPixel,(char *)mat.data);
    imageList.push_back(Mg_RGB);
}



TiffWriter::~TiffWriter()
{
    Magick::writeImages(imageList.begin(), imageList.end(), filename);
}


I have error on the Magick::Image line :
Error: Magick: unrecognized pixel map ``QSõ▒' @ error/pixel.c/ImportImagePixels/4243
I tried to changed the cv:mat image by a square 2x2 image and a random char value.
The problem persist, then it is not related to OpenCV.
When i watch the code of "pixel.c" line 4243, there is a switch case :

Code: Select all

switch (map[i])
    {
      case 'a':
      case 'A':
      {
        quantum_map[i]=AlphaQuantum;
        image->alpha_trait=BlendPixelTrait;
        break;
      }
      case 'B':
      case 'b':
      {
        quantum_map[i]=BlueQuantum;
        break;
}
...
default:
      {
        quantum_map=(QuantumType *) RelinquishMagickMemory(quantum_map);
        (void) ThrowMagickException(exception,GetMagickModule(),OptionError,
          "UnrecognizedPixelMap","`%s'",map);
        return(MagickFalse);
      }
}
Then it is as if i went in the "default" part of this "switch/case".

Do anybody have an idea about what can be the problem ?
Thanks !

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