AdvancedCompressionOptions (com.ironsoftware:ironpdf 2026.7.3 API)

java.lang.Object
- com.ironsoftware.ironpdf.compression.AdvancedCompressionOptions

public class AdvancedCompressionOptions
extends Object

Configuration for the advanced compression pipeline.

Recommended starting points:


 // Web/email — strongest size reduction
 AdvancedCompressionOptions web = new AdvancedCompressionOptions();
 web.setJpegQuality(70);
 web.setTargetImageDpi(150);
 web.setRemoveStructureTree(true);

 // Print quality
 AdvancedCompressionOptions print = new AdvancedCompressionOptions();
 print.setJpegQuality(90);
 print.setTargetImageDpi(300);

Mirrors the .NET AdvancedCompressionOptions class shipped in IronPdf 2026.6.

Constructor Summary

Constructors
Constructor and Description

AdvancedCompressionOptions()

Constructors
Constructor and Description
`AdvancedCompressionOptions()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`getCompressionLevel()` zlib compression level (0-9).
`Integer`	`getJpegQuality()` JPEG quality used when re-encoding images during optimization (1-100).
`ObjectStreamMode`	`getObjectStreams()` Object stream mode used when writing the output PDF.
`int`	`getOptimizeImagesMinArea()` Minimum image area (width × height pixels) for image optimization to apply.
`int`	`getOptimizeImagesMinHeight()` Minimum image height (in pixels) for image optimization to apply.
`int`	`getOptimizeImagesMinWidth()` Minimum image width (in pixels) for image optimization to apply.
`Integer`	`getTargetImageDpi()` Target DPI for image downsampling during advanced compression.
`boolean`	`isCoalesceContents()` Merge a page's separate content streams so they Flate-compress together.
`boolean`	`isCompressStreams()` Compress content streams using zlib/Flate.
`boolean`	`isDecodeGeneralizedStreams()` Decode generalized filters (FlateDecode, LZW, ASCII85, ASCIIHex) before re-encoding.
`boolean`	`isHighQualityImageSubsampling()` 4:4:4 chroma subsampling when true (better color), 4:1:1 when false (smaller).
`boolean`	`isRecompressFlate()` Re-compress already Flate-encoded streams using `getCompressionLevel()`.
`boolean`	`isRemoveStructureTree()` Remove the document structure tree before compression.
`boolean`	`isRemoveUnreferencedResources()` Drop indirect objects that are not referenced from the document catalog.
`boolean`	`pdfiumWillReEncode()` Returns true if pdfium-side image re-encoding is engaged (because a positive `targetImageDpi` was set).
`AdvancedCompressionOptions`	`setCoalesceContents(boolean v)`
`AdvancedCompressionOptions`	`setCompressionLevel(int v)`
`AdvancedCompressionOptions`	`setCompressStreams(boolean v)`
`AdvancedCompressionOptions`	`setDecodeGeneralizedStreams(boolean v)`
`AdvancedCompressionOptions`	`setHighQualityImageSubsampling(boolean v)`
`AdvancedCompressionOptions`	`setJpegQuality(Integer jpegQuality)`
`AdvancedCompressionOptions`	`setObjectStreams(ObjectStreamMode v)`
`AdvancedCompressionOptions`	`setOptimizeImagesMinArea(int v)`
`AdvancedCompressionOptions`	`setOptimizeImagesMinHeight(int v)`
`AdvancedCompressionOptions`	`setOptimizeImagesMinWidth(int v)`
`AdvancedCompressionOptions`	`setRecompressFlate(boolean v)`
`AdvancedCompressionOptions`	`setRemoveStructureTree(boolean v)`
`AdvancedCompressionOptions`	`setRemoveUnreferencedResources(boolean v)`
`AdvancedCompressionOptions`	`setTargetImageDpi(Integer targetImageDpi)`

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - AdvancedCompressionOptions
```
public AdvancedCompressionOptions()
```
- Method Detail
  - getJpegQuality
```
public Integer getJpegQuality()
```
    JPEG quality used when re-encoding images during optimization (1-100). When set, automatically enables image optimization.
    Recommended settings:
    - null — No image re-encoding (default)
    - 95 — Archival, minimal artifacts
    - 85 — High quality
    - 70 — Balanced, good for general use
    - 50 — Web/email; visible artifacts, smaller files
    Where the re-encoding happens depends on getTargetImageDpi():
    - targetImageDpi set (default 150): each image is downsampled and re-encoded at this quality. optimizeImages is skipped to avoid double JPEG encoding.
    - targetImageDpi = null: optimizeImages re-encodes images at this quality without changing pixel dimensions.
  - setJpegQuality
```
public AdvancedCompressionOptions setJpegQuality(Integer jpegQuality)
```
  - getTargetImageDpi
```
public Integer getTargetImageDpi()
```
    Target DPI for image downsampling during advanced compression. Images whose effective rendered DPI exceeds this value are box-filter downsampled to targetImageDpi before re-encoding.
    Recommended values:
    - 300 — Print quality, lossless to the eye at normal viewing distance
    - 200 — Crisp on high-DPI / retina screens
    - 150 — Default; best size/quality balance for screen + email
    - 96 — Aggressive; soft text but still readable
    - null — Disabled; preserve original resolution (largest file)
    Lossy. Once an image is downsampled it cannot be restored to its original resolution.
  - setTargetImageDpi
```
public AdvancedCompressionOptions setTargetImageDpi(Integer targetImageDpi)
```
  - isHighQualityImageSubsampling
```
public boolean isHighQualityImageSubsampling()
```
    4:4:4 chroma subsampling when true (better color), 4:1:1 when false (smaller).
  - setHighQualityImageSubsampling
```
public AdvancedCompressionOptions setHighQualityImageSubsampling(boolean v)
```
  - isRemoveStructureTree
```
public boolean isRemoveStructureTree()
```
    Remove the document structure tree before compression.
  - setRemoveStructureTree
```
public AdvancedCompressionOptions setRemoveStructureTree(boolean v)
```
  - isCompressStreams
```
public boolean isCompressStreams()
```
    Compress content streams using zlib/Flate.
  - setCompressStreams
```
public AdvancedCompressionOptions setCompressStreams(boolean v)
```
  - isRecompressFlate
```
public boolean isRecompressFlate()
```
    Re-compress already Flate-encoded streams using getCompressionLevel().
  - setRecompressFlate
```
public AdvancedCompressionOptions setRecompressFlate(boolean v)
```
  - getCompressionLevel
```
public int getCompressionLevel()
```
    zlib compression level (0-9). Default 9.
  - setCompressionLevel
```
public AdvancedCompressionOptions setCompressionLevel(int v)
```
  - getObjectStreams
```
public ObjectStreamMode getObjectStreams()
```
    Object stream mode used when writing the output PDF.
  - setObjectStreams
```
public AdvancedCompressionOptions setObjectStreams(ObjectStreamMode v)
```
  - isRemoveUnreferencedResources
```
public boolean isRemoveUnreferencedResources()
```
    Drop indirect objects that are not referenced from the document catalog.
  - setRemoveUnreferencedResources
```
public AdvancedCompressionOptions setRemoveUnreferencedResources(boolean v)
```
  - isCoalesceContents
```
public boolean isCoalesceContents()
```
    Merge a page's separate content streams so they Flate-compress together.
  - setCoalesceContents
```
public AdvancedCompressionOptions setCoalesceContents(boolean v)
```
  - isDecodeGeneralizedStreams
```
public boolean isDecodeGeneralizedStreams()
```
    Decode generalized filters (FlateDecode, LZW, ASCII85, ASCIIHex) before re-encoding.
  - setDecodeGeneralizedStreams
```
public AdvancedCompressionOptions setDecodeGeneralizedStreams(boolean v)
```
  - getOptimizeImagesMinWidth
```
public int getOptimizeImagesMinWidth()
```
    Minimum image width (in pixels) for image optimization to apply.
  - setOptimizeImagesMinWidth
```
public AdvancedCompressionOptions setOptimizeImagesMinWidth(int v)
```
  - getOptimizeImagesMinHeight
```
public int getOptimizeImagesMinHeight()
```
    Minimum image height (in pixels) for image optimization to apply.
  - setOptimizeImagesMinHeight
```
public AdvancedCompressionOptions setOptimizeImagesMinHeight(int v)
```
  - getOptimizeImagesMinArea
```
public int getOptimizeImagesMinArea()
```
    Minimum image area (width × height pixels) for image optimization to apply.
  - setOptimizeImagesMinArea
```
public AdvancedCompressionOptions setOptimizeImagesMinArea(int v)
```
  - pdfiumWillReEncode
```
public boolean pdfiumWillReEncode()
```
    Returns true if pdfium-side image re-encoding is engaged (because a positive targetImageDpi was set). The qpdf optimizeImages step is skipped in that case to avoid double JPEG encoding.

Class AdvancedCompressionOptions

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

AdvancedCompressionOptions

Method Detail

getJpegQuality

setJpegQuality

getTargetImageDpi

setTargetImageDpi

isHighQualityImageSubsampling

setHighQualityImageSubsampling

isRemoveStructureTree

setRemoveStructureTree

isCompressStreams

setCompressStreams

isRecompressFlate

setRecompressFlate

getCompressionLevel

setCompressionLevel

getObjectStreams

setObjectStreams

isRemoveUnreferencedResources

setRemoveUnreferencedResources

isCoalesceContents

setCoalesceContents

isDecodeGeneralizedStreams

setDecodeGeneralizedStreams

getOptimizeImagesMinWidth

setOptimizeImagesMinWidth

getOptimizeImagesMinHeight

setOptimizeImagesMinHeight

getOptimizeImagesMinArea

setOptimizeImagesMinArea

pdfiumWillReEncode