Function FillNVCVImageBufferStrided

python/mod_cvcuda/nvcv/Image.cpp:359–441

}

void FillNVCVImageBufferStrided(NVCVImageData &imgData, const std::vector<DLPackTensor> &infos, nvcv::ImageFormat fmt)
{
    // If user passes an image format, we must check if the given buffers are consistent with it.
    // Otherwise, we need to infer the image format from the given buffers.

    // Here's the plan:
    // 1. Loop through all buffers and infer its dimensions, number of channels and data type.
    //    In case of ambiguity in inferring data type for a buffer,
    //    - If available, use given image format for disambiguation
    //    - Otherwise, if number of channels in last dimension is <= 4, treat it as packed, or else it's planar
    // 2. Validate the data collected to see if it represents a real image format
    // 3. If available, compare the given image format with the inferred one, they're data layout must be the same.

    // Let the games begin.

    NVCVImageBufferStrided &dataStrided = imgData.buffer.strided;

    dataStrided = {}; // start anew

    std::vector<BufferImageInfo> bufferInfoList = ExtractBufferImageInfo(infos, fmt);
    std::vector<nvcv::DataType>  planeDataTypes;

    int curPlane = 0;
    for (const BufferImageInfo &b : bufferInfoList)
    {
        for (int p = 0; p < b.numPlanes; ++p, ++curPlane)
        {
            NVCV_ASSERT(curPlane <= 4);

            dataStrided.planes[curPlane].width     = b.size.w;
            dataStrided.planes[curPlane].height    = b.size.h;
            dataStrided.planes[curPlane].rowStride = b.rowStride;
            dataStrided.planes[curPlane].basePtr   = reinterpret_cast<NVCVByte *>(b.data) + b.planeStride * p;

            planeDataTypes.push_back(MakePackedType(b.dtype, b.isChannelLast ? b.numChannels : 1));
        }
    }
    dataStrided.numPlanes = curPlane;

    if (dataStrided.numPlanes == 0)
    {
        throw std::invalid_argument("Number of planes must be >= 1");
    }

    nvcv::ImageFormat inferredFormat = InferImageFormat(planeDataTypes);

    nvcv::ImageFormat finalFormat;

    // User explicitely specifies the image format?
    if (fmt != nvcv::FMT_NONE)
    {
        if (!HasSameDataLayout(fmt, inferredFormat))
        {
            throw std::invalid_argument(
                util::FormatString("Format inferred from buffers %s isn't compatible with given image format %s",
                                   util::ToString(inferredFormat).c_str(), util::ToString(fmt).c_str()));
        }
        finalFormat = fmt;