Resampling（重采样）

Zivid 的一个关键优势是固有的 2D 到 3D 映射。点云以有序数组形式返回，并且 RGB 值与其各自的点一一对应。

但是，3D 数据所需的分辨率并不总是与 2D 数据所需的分辨率相同。例如，人们通常需要比 3D 分辨率更高的 2D 分辨率。当您捕获单独的 2D 图像和 3D 点云时，2D 图像的分辨率可能高于 3D 点云。这可以通过 Sampling::Pixel 设置来实现，请参阅 Pixel 和 Pixel（像素）。

为了保持 2D 和 3D 数据之间的一一对应关系，可以对 3D 数据进行重新采样，以匹配 2D 数据的分辨率。这可以通过 Settings::Processing::Resampling 来完成。

重采样可以是上采样或降采样。以下两节将分别讨论这两者。

上采样 

通常用于匹配 2D 分辨率，当 3D 分辨率低于 2D 分辨率时使用。

例子

以下示例展示了如何捕获具有不同分辨率的 2D 和 3D 数据，同时保持 2D 和 3D 数据之间的一一对应关系。

2x2 子采样 3D 和全分辨率 2D

以下图片是使用全分辨率 2D 设置和子采样 3D 设置捕获的。3D 数据进一步进行上采样以匹配 2D 图像的分辨率。

C++

auto settings2D = Zivid::Settings2D{
    Zivid::Settings2D::Acquisitions{ Zivid::Settings2D::Acquisition{} },
    Zivid::Settings2D::Sampling::Pixel::all,
};
auto settings = Zivid::Settings{
    Zivid::Settings::Engine::phase,
    Zivid::Settings::Acquisitions{ Zivid::Settings::Acquisition{} },
    Zivid::Settings::Sampling::Pixel::blueSubsample2x2,
    Zivid::Settings::Sampling::Color::disabled,
    Zivid::Settings::Processing::Resampling::Mode::upsample2x2,
};

Python

settings_2d = zivid.Settings2D()
settings_2d.acquisitions.append(zivid.Settings2D.Acquisition())
settings_2d.sampling.pixel = zivid.Settings2D.Sampling.Pixel.all
settings = zivid.Settings()
settings.engine = "phase"
settings.acquisitions.append(zivid.Settings.Acquisition())
settings.sampling.pixel = zivid.Settings.Sampling.Pixel.blueSubsample2x2
settings.sampling.color = zivid.Settings.Sampling.Color.disabled
settings.processing.resampling.mode = zivid.Settings.Processing.Resampling.Mode.upsample2x2

全分辨率 2D

3D 深度图像

3D 点云

（旋转视角）

小心

注意箱子底部和棋盘格之间的点串。这是由于将3D数据进行上采样以匹配2D数据分辨率而产生的伪影。

4x4 子采样 3D 和 2x2 子采样 2D

以下图片是使用 2x2 子采样 2D 设置捕获的。3D 设置是 4x4 子采样，然后进行 2x2 上采样以匹配 2D 图像的分辨率。

C++

auto settings = Zivid::Settings{ Zivid::Settings::Acquisitions{ Zivid::Settings::Acquisition{} },
                                 Zivid::Settings::Color{ Zivid::Settings2D{
                                     Zivid::Settings2D::Acquisitions{ Zivid::Settings2D::Acquisition{} } } } };

auto model = camera.info().model();
switch(model.value())
{
    case Zivid::CameraInfo::Model::ValueType::zividTwo:
    case Zivid::CameraInfo::Model::ValueType::zividTwoL100:
    {
        settings.set(Zivid::Settings::Sampling::Pixel::blueSubsample2x2);
        settings.set(Zivid::Settings::Processing::Resampling::Mode::upsample2x2);
        settings.color().value().set(Zivid::Settings2D::Sampling::Pixel::all);
        break;
    }
    case Zivid::CameraInfo::Model::ValueType::zivid2PlusM130:
    case Zivid::CameraInfo::Model::ValueType::zivid2PlusM60:
    case Zivid::CameraInfo::Model::ValueType::zivid2PlusL110:
    {
        settings.set(Zivid::Settings::Sampling::Pixel::blueSubsample4x4);
        settings.set(Zivid::Settings::Processing::Resampling::Mode::upsample2x2);
        settings.color().value().set(Zivid::Settings2D::Sampling::Pixel::blueSubsample2x2);
        break;
    }
    case Zivid::CameraInfo::Model::ValueType::zivid2PlusMR130:
    case Zivid::CameraInfo::Model::ValueType::zivid2PlusMR60:
    case Zivid::CameraInfo::Model::ValueType::zivid2PlusLR110:
    {
        settings.set(Zivid::Settings::Sampling::Pixel::by4x4);
        settings.set(Zivid::Settings::Processing::Resampling::Mode::upsample2x2);
        settings.color().value().set(Zivid::Settings2D::Sampling::Pixel::by2x2);
        break;
    }
    case Zivid::CameraInfo::Model::ValueType::zividOnePlusSmall:
    case Zivid::CameraInfo::Model::ValueType::zividOnePlusMedium:
    case Zivid::CameraInfo::Model::ValueType::zividOnePlusLarge:
    {
        throw std::runtime_error("Unsupported camera model '" + model.toString() + "'");
    }
    default: throw std::runtime_error("Unhandled enum value '" + model.toString() + "'");
}

Python

settings = zivid.Settings(
    acquisitions=[zivid.Settings.Acquisition()],
    color=zivid.Settings2D(acquisitions=[zivid.Settings2D.Acquisition()]),
)

model = camera.info.model
if model in [zivid.CameraInfo.Model.zividTwo, zivid.CameraInfo.Model.zividTwoL100]:
    settings.sampling.pixel = zivid.Settings.Sampling.Pixel.blueSubsample2x2
    settings.processing.resampling.mode = zivid.Settings.Processing.Resampling.Mode.upsample2x2
    settings.color.sampling.pixel = zivid.Settings2D.Sampling.Pixel.all
elif model in [
    zivid.CameraInfo.Model.zivid2PlusM130,
    zivid.CameraInfo.Model.zivid2PlusM60,
    zivid.CameraInfo.Model.zivid2PlusL110,
]:
    settings.sampling.pixel = zivid.Settings.Sampling.Pixel.blueSubsample4x4
    settings.processing.resampling.mode = zivid.Settings.Processing.Resampling.Mode.upsample2x2
    settings.color.sampling.pixel = zivid.Settings2D.Sampling.Pixel.blueSubsample2x2
elif model in [
    zivid.CameraInfo.Model.zivid2PlusMR130,
    zivid.CameraInfo.Model.zivid2PlusMR60,
    zivid.CameraInfo.Model.zivid2PlusLR110,
]:
    settings.sampling.pixel = zivid.Settings.Sampling.Pixel.by4x4
    settings.processing.resampling.mode = zivid.Settings.Processing.Resampling.Mode.upsample2x2
    settings.color.sampling.pixel = zivid.Settings2D.Sampling.Pixel.by2x2
else:
    raise ValueError(f"Unsupported camera model '{model}'")