> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/core/layer-ocg/extract-layer.md).

# Extract layers from PDF on Server/Desktop

Learn how to extract PDF layers or OCG (optional content group) from a document with this comprehensive guide. Explore full sample code for creating, extracting, and rendering PDF layers efficiently.

To extract PDF layers or OCG (optional content group) from a document.

{% tabs %}
{% tab title="C#" %}
{% code lineNumbers="true" %}

```csharp
PDFDoc doc = new PDFDoc(filename);
Page page = doc.GetPage(1);

Config init_cfg = doc.GetOCGConfig();
Context ctx = new Context(init_cfg);

PDFDraw pdfdraw = new PDFDraw();
pdfdraw.SetImageSize(1000, 1000);
pdfdraw.SetOCGContext(ctx); // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.SetNonOCDrawing(false);

// Now render each layer in the input document to a separate image.
Obj ocgs = doc.GetOCGs(); // Get the array of all OCGs in the document.
int i, sz = ocgs.Size();
for (i=0; i<sz; ++i)
{
    Group ocg = new Group(ocgs.GetAt(i));
    ctx.ResetStates(false);
    ctx.SetState(ocg, true);
    string fname = "pdf_layers_" + ocg.GetName() + ".png";
    pdfdraw.Export(page, output_path + fname);
}

// Now draw content that is not part of any layer...
ctx.SetNonOCDrawing(true);
ctx.SetOCDrawMode(Context.OCDrawMode.e_NoOC);
pdfdraw.Export(page, output_path + "pdf_layers_non_oc.png");
```

{% endcode %}
{% endtab %}

{% tab title="C++" %}
{% code lineNumbers="true" %}

```cpp
PDFDoc doc(filename);
Page page = doc.GetPage(1);

OCG::Config init_cfg = doc.GetOCGConfig();
OCG::Context ctx(init_cfg);

PDFDraw pdfdraw;
pdfdraw.SetImageSize(1000, 1000);
pdfdraw.SetOCGContext(&ctx); // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.SetNonOCDrawing(false);

// Now render each layer in the input document to a separate image.
Obj ocgs = doc.GetOCGs(); // Get the array of all OCGs in the document.
int i, sz = int(ocgs.Size());
for (i=0; i<sz; ++i) {
    OCG::Group ocg(ocgs.GetAt(i));
    ctx.ResetStates(false);
    ctx.SetState(ocg, true);
    std::string fname("pdf_layers_");
    fname += ocg.GetName().ConvertToAscii();
    fname += ".png";
    pdfdraw.Export(page, (output_path + fname).c_str());
}

// Now draw content that is not part of any layer...
ctx.SetNonOCDrawing(true);
ctx.SetOCDrawMode(OCG::Context::e_NoOC);
pdfdraw.Export(page, (output_path + "pdf_layers_non_oc.png").c_str());
```

{% endcode %}
{% endtab %}

{% tab title="Go" %}
{% code lineNumbers="true" %}

```go
doc := NewPDFDoc(filename)
page = doc.GetPage(1)

init_cfg := doc.GetOCGConfig()
ctx := NewContext(init_cfg)

pdfdraw := NewPDFDraw()
pdfdraw.SetImageSize(1000, 1000)
pdfdraw.SetOCGContext(ctx)  // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.SetNonOCDrawing(false)

// Now render each layer in the input document to a separate image.
ocgs := doc.GetOCGs()    // Get the array of all OCGs in the document.
if ocgs != nil{
    sz := ocgs.Size()
    i := int64(0)
    for i < sz{
        ocg := NewGroup(ocgs.GetAt(i))
        ctx.ResetStates(false)
        ctx.SetState(ocg, true)
        fname := "pdf_layers_" + ocg.GetName() + ".png"
        fmt.Println(fname)
        pdfdraw.Export(page, outputPath + fname)
        i = i + 1
    }
}

// Now draw content that is not part of any layer...
ctx.SetNonOCDrawing(true)
ctx.SetOCDrawMode(ContextE_NoOC)
pdfdraw.Export(page, outputPath + "pdf_layers_non_oc.png")
```

{% endcode %}
{% endtab %}

{% tab title="Java" %}
{% code lineNumbers="true" %}

```java
PDFDoc doc = new PDFDoc(filename);
Page page = doc.getPage(1);

Config init_cfg = doc.getOCGConfig();
Context ctx = new Context(init_cfg);

PDFDraw pdfdraw = new PDFDraw();
pdfdraw.setImageSize(1000, 1000);
pdfdraw.setOCGContext(ctx); // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.setNonOCDrawing(false);

// Now render each layer in the input document to a separate image.
Obj ocgs = doc.getOCGs(); // Get the array of all OCGs in the document.
int i, sz = (int) ocgs.size();
for (i = 0; i < sz; ++i) {
    Group ocg = new Group(ocgs.getAt(i));
    ctx.resetStates(false);
    ctx.setState(ocg, true);
    String fname = "pdf_layers_" + ocg.getName() + ".png";
    pdfdraw.export(page, output_path + fname);
}

// Now draw content that is not part of any layer...
ctx.setNonOCDrawing(true);
ctx.setOCDrawMode(Context.e_NoOC);
pdfdraw.export(page, output_path + "pdf_layers_non_oc.png");
```

{% endcode %}
{% endtab %}

{% tab title="JavaScript" %}
{% code lineNumbers="true" %}

```js
async function main() {
    const doc = await PDFNet.PDFDoc.createFromURL(filename);
    const page = await doc.getPage(1);

    const initCfg = await doc.getOCGConfig();
    const ctx = await PDFNet.OCGContext.createFromConfig(initCfg);

    const pdfdraw = await PDFNet.PDFDraw.create();
    pdfdraw.setImageSize(1000, 1000);
    pdfdraw.setOCGContext(ctx);

    // Disable drawing of content that is not optional (i.e. is not part of any layer).
    ctx.setNonOCDrawing(false);

    // Now render each layer in the input document to a separate image.
    const ocgs = await doc.getOCGs(); // Get the array of all OCGs in the document.
    let i;
    const sz = await ocgs.size();
    for (i = 0; i < sz; ++i) {
        const ocg = await PDFNet.OCG.createFromObj(await ocgs.getAt(i));
        ctx.resetStates(false);
        ctx.setState(ocg, true);
        let fname = 'pdf_layers_';
        fname += await ocg.getName();
        fname += '.png';
        const pageBuffer = await pdfdraw.exportStream(page);
        const imageData = new Blob([pageBuffer], {type: 'image/png'}));
    }

    // Now draw content that is not part of any layer...
    ctx.setNonOCDrawing(true);
    ctx.setOCDrawMode(PDFNet.OCGContext.OCDrawMode.e_NoOC);
    const nonLayerBuffer = await pdfdraw.exportStream(page);
    const data = new Blob([nonLayerBuffer], {type: 'image/png'}));
}
PDFNet.runWithCleanup(main);
```

{% endcode %}
{% endtab %}

{% tab title="Kotlin" %}
{% code lineNumbers="true" %}

```kotlin
val doc = PDFDoc(filename)
val page = doc.getPage(1)

val init_cfg = doc.ocgConfig
val ctx = Context(init_cfg)

val pdfdraw = PDFDraw()
pdfdraw.setImageSize(1000, 1000)
pdfdraw.setOCGContext(ctx) // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.setNonOCDrawing(false)

// Now render each layer in the input document to a separate image.
val ocgs = doc.ocGs // Get the array of all OCGs in the document.
var i: Int
val sz = ocgs.size().toInt()
i = 0
while (i < sz) {
    val ocg = Group(ocgs.getAt(i))
    ctx.resetStates(false)
    ctx.setState(ocg, true)
    val fname = "pdf_layers_" + ocg.name + ".png"
    pdfdraw.export(page, output_path + fname)
    ++i
}

// Now draw content that is not part of any layer...
ctx.setNonOCDrawing(true)
ctx.setOCDrawMode(Context.e_NoOC)
pdfdraw.export(page, output_path + "pdf_layers_non_oc.png")
```

{% endcode %}
{% endtab %}

{% tab title="Obj-C" %}
{% code lineNumbers="true" %}

```objc
PTPDFDoc *doc = [[PTPDFDoc alloc] initWithFilepath: filename];
PTPage *page = [doc GetPage: 1];

PTConfig *init_cfg = [doc GetOCGConfig];
PTContext *ctx = [[PTContext alloc] initWithConfig: init_cfg];

PTPDFDraw *pdfdraw = [[PTPDFDraw alloc] initWithDpi: 92];
[pdfdraw SetImageSize: 1000 height: 1000 preserve_aspect_ratio: YES];
[pdfdraw SetOCGContext: ctx]; // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
[ctx SetNonOCDrawing: NO];

// Now render each layer in the input document to a separate image.
PTObj * ocgs = [doc GetOCGs]; // Get the array of all OCGs in the document.
unsigned long i, sz = [ocgs Size];
for (i=0; i<sz; ++i) {
    PTGroup *ocg = [[PTGroup alloc] initWithOcg: [ocgs GetAt: i]];
    [ctx ResetStates: NO];
    [ctx SetState: ocg state: YES];
    NSString* fname = [output_path stringByAppendingFormat: @"pdf_layers_%@.png", [ocg GetName]];
    [pdfdraw  page filename: fname format: @"PNG"];
}

// Now draw content that is not part of any layer...
[ctx SetNonOCDrawing: YES];
[ctx SetOCDrawMode: e_ptNoOC];
[pdfdraw  page filename: [output_path stringByAppendingString: @"pdf_layers_non_oc.png"] format: @"PNG" ];
```

{% endcode %}
{% endtab %}

{% tab title="Swift" %}
{% code lineNumbers="true" %}

```swift
let doc: PTPDFDoc = PTPDFDoc(filepath: filename)
let page: PTPage = doc.getPage(1)

let init_cfg: PTConfig = doc.getOCGConfig()
let ctx: PTContext = PTContext(config: init_cfg)

let pdfdraw: PTPDFDraw = PTPDFDraw(dpi: 92)
pdfdraw.setImageSize(1000, height: 1000, preserve_aspect_ratio: true)
pdfdraw.setOCGContext(ctx)    // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.setNonOCDrawing(false)

// Now render each layer in the input document to a separate image.
let ocgs: PTObj = doc.getOCGs() {    // Get the array of all OCGs in the document.
var _: UInt = 0
let sz: UInt = ocgs.size()
for i in 0..<sz {
    let ocg: PTGroup = PTGroup(ocg: ocgs.getAt(i))
    ctx.resetStates(false)
    ctx.setState(ocg, state: true)
    let fname: String = output_path + "pdf_layers_\(ocg.getName()).png")
    pdfdraw.export(page, filename: fname, format: "PNG")
}

// Now draw content that is not part of any layer...
ctx.setNonOCDrawing(true)
ctx.setOCDrawMode(e_ptNoOC)
pdfdraw.export(page, filename: output_path + "pdf_layers_non_oc.png", format: "PNG")
```

{% endcode %}
{% endtab %}

{% tab title="PHP" %}
{% code lineNumbers="true" %}

```php
$doc = new PDFDoc($filename);
$page = $doc->GetPage(1);

$init_cfg = $doc->GetOCGConfig();
$ctx = new Context($init_cfg);

$pdfdraw = new PDFDraw();
$pdfdraw->SetImageSize(1000, 1000);
$pdfdraw->SetOCGContext($ctx); // Render the page using the given OCG context.

// Disable drawing of content that is not optional (i.e. is not part of any layer).
$ctx->SetNonOCDrawing(false);

// Now render each layer in the input document to a separate image.
$ocgs = $doc->GetOCGs(); // Get the array of all OCGs in the document.
$sz = $ocgs->Size();
for ($i=0; $i<$sz; ++$i) {
    $ocg = new Group($ocgs->GetAt($i));
    $ctx->ResetStates(false);
    $ctx->SetState($ocg, true);
    $fname = "pdf_layers_".$ocg->GetName().".png";
    $pdfdraw->Export($page, $output_path.$fname);
}

// Now draw content that is not part of any layer...
$ctx->SetNonOCDrawing(true);
$ctx->SetOCDrawMode(Context::e_NoOC);
$pdfdraw->Export($page, $output_path."pdf_layers_non_oc.png");
```

{% endcode %}
{% endtab %}

{% tab title="Python" %}
{% code lineNumbers="true" %}

```python
doc = PDFDoc(filename)
page = doc.GetPage(1)

init_cfg = doc.GetOCGConfig()
ctx = Context(init_cfg)

pdfdraw = PDFDraw()
pdfdraw.SetImageSize(1000, 1000)
pdfdraw.SetOCGContext(ctx)  # Render the page using the given OCG context.

# Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.SetNonOCDrawing(False)

# Now render each layer in the input document to a separate image.
ocgs = doc.GetOCGs()    # Get the array of all OCGs in the document.
sz = ocgs.Size()
i = 0
while i < sz:
    ocg = Group(ocgs.GetAt(i))
    ctx.ResetStates(False)
    ctx.SetState(ocg, True)
    fname = "pdf_layers_" + ocg.GetName() + ".png"
    pdfdraw.Export(page, output_path + fname)
    i = i + 1

# Now draw content that is not part of any layer...
ctx.SetNonOCDrawing(True)
ctx.SetOCDrawMode(Context.e_NoOC)
pdfdraw.Export(page, output_path + "pdf_layers_non_oc.png")
```

{% endcode %}
{% endtab %}

{% tab title="Ruby" %}
{% code lineNumbers="true" %}

```ruby
doc = PDFDoc.new($filename)
page = doc.GetPage(1)

init_cfg = doc.GetOCGConfig
ctx = Context.new(init_cfg)

pdfdraw = PDFDraw.new
pdfdraw.SetImageSize(1000, 1000)
pdfdraw.SetOCGContext(ctx)  # Render the page using the given OCG context.

# Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.SetNonOCDrawing(false)

# Now render each layer in the input document to a separate image.
ocgs = doc.GetOCGs	# Get the array of all OCGs in the document.
sz = ocgs.Size
i = 0
while i < sz do
    ocg = Group.new(ocgs.GetAt(i))
    ctx.ResetStates(false)
    ctx.SetState(ocg, true)
    fname = "pdf_layers_" + ocg.GetName + ".png"
    pdfdraw.Export(page, $output_path + fname)
    i = i + 1
end

# Now draw content that is not part of any layer...
ctx.SetNonOCDrawing(true)
ctx.SetOCDrawMode(Context::E_NoOC)
pdfdraw.Export(page, $output_path + "pdf_layers_non_oc.png")
```

{% endcode %}
{% endtab %}

{% tab title="VB" %}
{% code lineNumbers="true" %}

```vb
Dim doc As PDFDoc = New PDFDoc(filename)
Dim page As Page = doc.GetPage(1)

Dim init_cfg As Config = doc.GetOCGConfig()
Dim ctx As Context = New Context(init_cfg)

Dim pdfdraw As PDFDraw = New PDFDraw
pdfdraw.SetImageSize(1000, 1000)
pdfdraw.SetOCGContext(ctx)  ' Render the page using the given OCG context.

' Disable drawing of content that is not optional (i.e. is not part of any layer).
ctx.SetNonOCDrawing(False)

' Now render each layer in the input document to a separate image.
Dim ocgs As Obj = doc.GetOCGs()			 ' Get the array of all OCGs in the document.
Dim i As Integer = 0
Dim sz As Integer = ocgs.Size()
While (i < sz)
    Dim ocg As Group = New Group(ocgs.GetAt(i))
    ctx.ResetStates(False)
    ctx.SetState(ocg, True)
    Dim fname As String =  "pdf_layers_" + ocg.GetName() + ".png"
    pdfdraw.Export(page, output_path + fname)
    i = i + 1
End While

' Now draw content that is not part of any layer...
ctx.SetNonOCDrawing(True)
ctx.SetOCDrawMode(Context.OCDrawMode.e_NoOC)
pdfdraw.Export(page, output_path + "pdf_layers_non_oc.png")
```

{% endcode %}
{% endtab %}
{% endtabs %}

[PDF layers (OCG)](/core/get-started/samples/pdflayerstest.md) Full sample code which demonstrates how to create, extract, render PDF layers. Code sample is available in C++, C#, Java, Python, Go, PHP, Ruby & VB.


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