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# holoscan::data_loggers::SimpleTextSerializer

```cpp showLineNumbers={false}
#include <holoscan/data_loggers/simple_text_serializer.hpp>
```

**Inherits from:** `holoscan::Resource` (public)

---

## Constructors

### SimpleTextSerializer \[#simpletextserializer]

```cpp showLineNumbers={false}
holoscan::data_loggers::SimpleTextSerializer::SimpleTextSerializer() = default
```

### Destructor \[#destructor]

### \~SimpleTextSerializer

```cpp showLineNumbers={false}
holoscan::data_loggers::SimpleTextSerializer::~SimpleTextSerializer() override = default
```

---

## Methods

### setup \[#setup]

```cpp showLineNumbers={false}
void holoscan::data_loggers::SimpleTextSerializer::setup(
    ComponentSpec &spec
) override
```

Define the resource specification.

**Parameters**

**`spec`** `ComponentSpec &`

The reference to the component specification.

---

### can\_handle\_message \[#canhandlemessage]

```cpp showLineNumbers={false}
bool holoscan::data_loggers::SimpleTextSerializer::can_handle_message(
    const std::type_info &message_type
) const
```

### serialize\_to\_string \[#serializetostring]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::serialize_to_string(
    const std::any &data
)
```

Serialize data to a simple text string.

### serialize\_tensor\_to\_string \[#serializetensortostring]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::serialize_tensor_to_string(
    const std::shared_ptr<Tensor> &tensor,
    bool log_data_content = false,
    std::optional<cudaStream_t> stream = std::nullopt
)
```

Serialize tensor data to a simple text string.

### serialize\_tensormap\_to\_string \[#serializetensormaptostring]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::serialize_tensormap_to_string(
    const TensorMap &tensor_map,
    bool log_data_content = false,
    std::optional<cudaStream_t> stream = std::nullopt
)
```

Serialize tensor map data to a simple text string.

### serialize\_metadata\_to\_string \[#serializemetadatatostring]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::serialize_metadata_to_string(
    const std::shared_ptr<MetadataDictionary> &metadata
)
```

Serialize metadata to a simple text string.

### serialize\_video\_buffer\_to\_string \[#serializevideobuffertostring]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::serialize_video_buffer_to_string(
    const nvidia::gxf::Handle<nvidia::gxf::VideoBuffer> &video_buffer,
    std::optional<cudaStream_t> stream = std::nullopt
)
```

Serialize video buffer data to a simple text string.

### register\_encoder \[#registerencoder]

```cpp showLineNumbers={false}
template <typename T>
void holoscan::data_loggers::SimpleTextSerializer::register_encoder(
    std::function<std::string(const std::any &)> encoder
)
```

Register a custom encoder for a specific type.

**Template parameters**

**`T`** `typename`

The type to register an encoder for

---

**Parameters**

**`encoder`** `std::function<std::string(const std::any &)>`

Function that takes const std::any& and returns std::string

---

### resource\_type \[#resourcetype]

```cpp showLineNumbers={false}
ResourceType holoscan::data_loggers::SimpleTextSerializer::resource_type() const
```

Get the resource type.

**Returns:** The resource type.

### name \[#name]

#### Set the name of the resource (1)

```cpp showLineNumbers={false}
Resource & holoscan::data_loggers::SimpleTextSerializer::name(
    const std::string &name
) &
```

Set the name of the resource.

**Returns:** The reference to the resource.

**Parameters**

**`name`** `const std::string &`

The name of the resource.

---

#### Set the name of the resource (2)

```cpp showLineNumbers={false}
Resource && holoscan::data_loggers::SimpleTextSerializer::name(
    const std::string &name
) &&
```

Set the name of the resource.

**Returns:** The reference to the resource.

**Parameters**

**`name`** `const std::string &`

The name of the resource.

---

#### Const

const

```cpp showLineNumbers={false}
const std::string & holoscan::ComponentBase::name() const
```

Get the name of the component.

**Returns:** The name of the component.

### fragment \[#fragment]

#### Set the fragment of the resource

```cpp showLineNumbers={false}
Resource & holoscan::data_loggers::SimpleTextSerializer::fragment(
    Fragment *fragment
)
```

Set the fragment of the resource.

**Returns:** The reference to the resource.

**Parameters**

**`fragment`** `Fragment *`

The pointer to the fragment of the resource.

---

#### Overload 2

```cpp showLineNumbers={false}
Fragment * holoscan::ComponentBase::fragment()
```

Get a pointer to [Fragment](../../../classes/fragment) object.

**Returns:** The Pointer to [Fragment](../../../classes/fragment) object.

#### Const

const

```cpp showLineNumbers={false}
const Fragment * holoscan::ComponentBase::fragment() const
```

Get a const pointer to [Fragment](../../../classes/fragment) object.

**Returns:** The const pointer to [Fragment](../../../classes/fragment) object.

### spec \[#spec]

#### Set the component specification to the resource

```cpp showLineNumbers={false}
Resource & holoscan::data_loggers::SimpleTextSerializer::spec(
    const std::shared_ptr<ComponentSpec> &spec
)
```

Set the component specification to the resource.

**Returns:** The reference to the resource.

**Parameters**

**`spec`** `const std::shared_ptr<ComponentSpec> &`

The component specification.

---

#### Get the component specification of the resource

```cpp showLineNumbers={false}
ComponentSpec * holoscan::data_loggers::SimpleTextSerializer::spec()
```

Get the component specification of the resource.

**Returns:** The pointer to the component specification.

### spec\_shared \[#specshared]

```cpp showLineNumbers={false}
std::shared_ptr<ComponentSpec> holoscan::data_loggers::SimpleTextSerializer::spec_shared()
```

Get the shared pointer to the component spec.

**Returns:** The shared pointer to the component spec.

### initialize \[#initialize]

```cpp showLineNumbers={false}
void holoscan::data_loggers::SimpleTextSerializer::initialize() override
```

Initialize the component.

This method is called only once when the component is created for the first time, and use of light-weight initialization.

### to\_yaml\_node \[#toyamlnode]

```cpp showLineNumbers={false}
YAML::Node holoscan::data_loggers::SimpleTextSerializer::to_yaml_node() const override
```

Get a `YAML` representation of the resource.

**Returns:** `YAML` node including spec of the resource in addition to the base component properties.

### set\_parameters \[#setparameters]

```cpp showLineNumbers={false}
void holoscan::data_loggers::SimpleTextSerializer::set_parameters() override
```

Set the parameters based on defaults (sets GXF parameters for GXF components).

### id \[#id]

```cpp showLineNumbers={false}
int64_t holoscan::ComponentBase::id() const
```

Get the identifier of the component.

By default, the identifier is set to -1. It is set to a valid value when the component is initialized.

With the default executor (GXFExecutor), the identifier is set to the GXF component ID.

**Returns:** The identifier of the component.

### add\_arg \[#addarg]

#### Add an argument to the component (1)

```cpp showLineNumbers={false}
void holoscan::ComponentBase::add_arg(
    const Arg &arg
)
```

Add an argument to the component.

**Parameters**

**`arg`** `const Arg &`

The argument to add.

---

#### Add an argument to the component (2)

```cpp showLineNumbers={false}
void holoscan::ComponentBase::add_arg(
    Arg &&arg
)
```

Add an argument to the component.

**Parameters**

**`arg`** `Arg &&`

The argument to add.

---

#### Add a list of arguments to the component (1)

```cpp showLineNumbers={false}
void holoscan::ComponentBase::add_arg(
    const ArgList &arg
)
```

Add a list of arguments to the component.

**Parameters**

**`arg`** `const ArgList &`

The list of arguments to add.

---

#### Add a list of arguments to the component (2)

```cpp showLineNumbers={false}
void holoscan::ComponentBase::add_arg(
    ArgList &&arg
)
```

Add a list of arguments to the component.

**Parameters**

**`arg`** `ArgList &&`

The list of arguments to add.

---

### args \[#args]

```cpp showLineNumbers={false}
std::vector<Arg> & holoscan::ComponentBase::args()
```

Get the list of arguments.

**Returns:** The vector of arguments.

### description \[#description]

```cpp showLineNumbers={false}
std::string holoscan::ComponentBase::description() const
```

Get a description of the component.

**Returns:** `YAML` string.

**See also:**
to\_yaml\_node()

### service \[#service]

```cpp showLineNumbers={false}
template <typename ServiceT = DefaultFragmentService>
std::shared_ptr<ServiceT> holoscan::ComponentBase::service(
    std::string_view id = ""
) const
```

Retrieve a registered fragment service or resource.

Retrieves a previously registered fragment service or resource by its type and optional identifier. Returns nullptr if no service/resource is found with the specified type and identifier.

Note that any changes to the service retrieval logic in this method should be synchronized with the implementation in `Fragment::service()` method to maintain consistency.

**Returns:** The shared pointer to the service/resource, or nullptr if not found or if type casting fails.

**Template parameters**

**`ServiceT`** `typename`

The type of the service/resource to retrieve. Must inherit from either [Resource](../../../classes/resource) or [FragmentService](../../../classes/fragmentservice). Defaults to [DefaultFragmentService](../../../classes/defaultfragmentservice) if not specified.

---

**Parameters**

**`id`** `std::string_view` — default: ""

The identifier of the service/resource. If empty, retrieves by type only.

---

### get\_service\_by\_type\_info \[#getservicebytypeinfo]

```cpp showLineNumbers={false}
std::shared_ptr<FragmentService> holoscan::ComponentBase::get_service_by_type_info(
    const std::type_info &service_type,
    std::string_view id = ""
) const
```

Retrieve a registered fragment service or resource for Python bindings.

This is a helper method for Python bindings to retrieve a service by its C++ type info.

**Returns:** The shared pointer to the base service, or nullptr if not found.

**Parameters**

**`service_type`** `const std::type_info &`

The type info of the service/resource to retrieve.

---

**`id`** `std::string_view` — default: ""

The identifier of the service/resource. If empty, retrieves by type only.

---

### reset\_backend\_objects \[#resetbackendobjects]

```cpp showLineNumbers={false}
virtual void holoscan::ComponentBase::reset_backend_objects()
```

Reset any backend-specific objects (e.g. GXF GraphEntity).

### initialize\_default\_encoders \[#initializedefaultencoders]

```cpp showLineNumbers={false}
void holoscan::data_loggers::SimpleTextSerializer::initialize_default_encoders()
```

### format\_vector \[#formatvector]

```cpp showLineNumbers={false}
template <typename T>
std::string holoscan::data_loggers::SimpleTextSerializer::format_vector(
    const std::vector<T> &vec
) const
```

### format\_metadata\_dict \[#formatmetadatadict]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::format_metadata_dict(
    const MetadataDictionary &dict
) const
```

### to\_string \[#tostring]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::to_string(
    const std::any &data
) const
```

### get\_video\_format\_info \[#getvideoformatinfo]

```cpp showLineNumbers={false}
VideoFormatInfo holoscan::data_loggers::SimpleTextSerializer::get_video_format_info(
    nvidia::gxf::VideoFormat format
) const
```

Detect video format information from GXF VideoFormat.

**Returns:** VideoFormatInfo containing channels, element type, and support status

**Parameters**

**`format`** `nvidia::gxf::VideoFormat`

The GXF video format to analyze

---

### serialize\_pixel\_data \[#serializepixeldata]

```cpp showLineNumbers={false}
std::string holoscan::data_loggers::SimpleTextSerializer::serialize_pixel_data(
    const void *data_ptr,
    VideoElementType element_type,
    int channels,
    size_t pixels_to_show,
    size_t total_pixels
) const
```

Serialize pixel data to string representation.

**Returns:** String representation of the pixel data

**Parameters**

**`data_ptr`** `const void *`

Pointer to the pixel data

---

**`element_type`** `VideoElementType`

Type of elements in the data

---

**`channels`** `int`

Number of channels per pixel

---

**`pixels_to_show`** `size_t`

Number of pixels to serialize

---

**`total_pixels`** `size_t`

Total number of pixels (for truncation message)

---

### update\_params\_from\_args \[#updateparamsfromargs]

#### Update parameters based on the specified arguments

```cpp showLineNumbers={false}
void holoscan::data_loggers::SimpleTextSerializer::update_params_from_args()
```

Update parameters based on the specified arguments.

#### Update parameters based on the specified arguments (with params)

```cpp showLineNumbers={false}
void holoscan::ComponentBase::update_params_from_args(
    std::unordered_map<std::string, ParameterWrapper> &params
)
```

Update parameters based on the specified arguments.

### service\_provider \[#serviceprovider]

```cpp showLineNumbers={false}
void holoscan::ComponentBase::service_provider(
    FragmentServiceProvider *provider
)
```

Set the service provider that owns this component.

---

## Static methods

### register\_converter \[#registerconverter]

```cpp showLineNumbers={false}
template <typename typeT>
static void holoscan::ComponentBase::register_converter()
```

Register the argument setter for the given type.

If an operator or resource has an argument with a custom type, the argument setter must be registered using this method.

The argument setter is used to set the value of the argument from the `YAML` configuration.

This method can be called in the initialization phase of the operator/resource (e.g., `initialize()`). The example below shows how to register the argument setter for the custom type (`Vec3`):

It is assumed that `YAML::convert<T>::encode` and `YAML::convert<T>::decode` are implemented for the given type. You need to specialize the `YAML::convert<>` template class.

For example, suppose that you had a `Vec3` class with the following members:

You can define the `YAML::convert<Vec3>` as follows in a '.cpp' file:

Please refer to the [yaml-cpp documentation](https://github.com/jbeder/yaml-cpp/wiki/Tutorial#converting-tofrom-native-data-types) for more details.

**Template parameters**

**`typeT`** `typename`

The type of the argument to register.

---

**Example**

```cpp showLineNumbers={false}
void MyOp::initialize() {
  register_converter<Vec3>();
}
```

**Example**

```cpp showLineNumbers={false}
struct Vec3 {
  // make sure you have overloaded operator==() for the comparison
  double x, y, z;
};
```

**Example**

```cpp showLineNumbers={false}
namespace YAML {
template<>
struct convert<Vec3> {
  static Node encode(const Vec3& rhs) {
    Node node;
    node.push_back(rhs.x);
    node.push_back(rhs.y);
    node.push_back(rhs.z);
    return node;
  }

  static bool decode(const Node& node, Vec3& rhs) {
    if(!node.IsSequence() || node.size() != 3) {
      return false;
    }

    rhs.x = node[0].as<double>();
    rhs.y = node[1].as<double>();
    rhs.z = node[2].as<double>();
    return true;
  }
};
}
```

### register\_argument\_setter \[#registerargumentsetter]

```cpp showLineNumbers={false}
template <typename typeT>
void holoscan::ComponentBase::register_argument_setter()
```

Register the argument setter for the given type.

Please refer to the documentation of `register_converter()` for more details.

**Template parameters**

**`typeT`** `typename`

The type of the argument to register.

---

---

## Types

### VideoElementType

| Name       | Value | Description |
| ---------- | ----- | ----------- |
| `kUINT8`   |       |             |
| `kUINT16`  |       |             |
| `kUINT32`  |       |             |
| `kFLOAT32` |       |             |
| `kFLOAT64` |       |             |

### ResourceType

[Resource](../../../classes/resource) type used for the initialization of the resource.

| Name      | Value | Description      |
| --------- | ----- | ---------------- |
| `kNative` |       | Native resource. |
| `kGXF`    |       | GXF resource.    |

---

## Member variables

| Name                        | Type                                                                                   | Description                                       |
| --------------------------- | -------------------------------------------------------------------------------------- | ------------------------------------------------- |
| `max_elements_`             | `Parameter< int64_t >`                                                                 |                                                   |
| `max_metadata_items_`       | `Parameter< int64_t >`                                                                 |                                                   |
| `log_video_buffer_content_` | `Parameter< bool >`                                                                    |                                                   |
| `encoders_`                 | `std::unordered_map< std::type_index, std::function< std::string(const std::any &)> >` |                                                   |
| `resource_type_`            | `ResourceType`                                                                         | The type of the resource.                         |
| `is_initialized_`           | `bool`                                                                                 | Whether the resource is initialized.              |
| `spec_`                     | `std::shared_ptr< ComponentSpec >`                                                     | The component specification.                      |
| `id_`                       | `int64_t`                                                                              | The ID of the component.                          |
| `name_`                     | `std::string`                                                                          | Name of the component.                            |
| `fragment_`                 | `Fragment *`                                                                           | Pointer to the fragment that owns this component. |
| `args_`                     | `std::vector< Arg >`                                                                   | List of arguments.                                |
| `service_provider_`         | `FragmentServiceProvider *`                                                            | Pointer to the service provider.                  |

---

## Inner classes

### VideoFormatInfo

```cpp showLineNumbers={false}
struct holoscan::data_loggers::SimpleTextSerializer::VideoFormatInfo
```

| Name           | Type               | Description |
| -------------- | ------------------ | ----------- |
| `channels`     | `int`              |             |
| `element_type` | `VideoElementType` |             |
| `supported`    | `bool`             |             |