Function cvCreateData

deps/opencv/modules/core/src/array.cpp:794–884

Allocates underlying array data

// Allocates underlying array data
CV_IMPL void
cvCreateData( CvArr* arr )
{
    if( CV_IS_MAT_HDR_Z( arr ))
    {
        size_t step, total_size;
        CvMat* mat = (CvMat*)arr;
        step = mat->step;

        if( mat->rows == 0 || mat->cols == 0 )
            return;

        if( mat->data.ptr != 0 )
            CV_Error( CV_StsError, "Data is already allocated" );

        if( step == 0 )
            step = CV_ELEM_SIZE(mat->type)*mat->cols;

        int64 _total_size = (int64)step*mat->rows + sizeof(int) + CV_MALLOC_ALIGN;
        total_size = (size_t)_total_size;
        if(_total_size != (int64)total_size)
            CV_Error(CV_StsNoMem, "Too big buffer is allocated" );
        mat->refcount = (int*)cvAlloc( (size_t)total_size );
        mat->data.ptr = (uchar*)cvAlignPtr( mat->refcount + 1, CV_MALLOC_ALIGN );
        *mat->refcount = 1;
    }
    else if( CV_IS_IMAGE_HDR(arr))
    {
        IplImage* img = (IplImage*)arr;

        if( img->imageData != 0 )
            CV_Error( CV_StsError, "Data is already allocated" );

        if( !CvIPL.allocateData )
        {
            img->imageData = img->imageDataOrigin =
                        (char*)cvAlloc( (size_t)img->imageSize );
        }
        else
        {
            int depth = img->depth;
            int width = img->width;

            if( img->depth == IPL_DEPTH_32F || img->depth == IPL_DEPTH_64F )
            {
                img->width *= img->depth == IPL_DEPTH_32F ? sizeof(float) : sizeof(double);
                img->depth = IPL_DEPTH_8U;
            }

            CvIPL.allocateData( img, 0, 0 );

            img->width = width;
            img->depth = depth;
        }
    }
    else if( CV_IS_MATND_HDR( arr ))
    {
        CvMatND* mat = (CvMatND*)arr;