Optimize-PptImages

A cross-platform PowerShell script that intelligently optimizes PowerPoint presentations by resizing oversized images, applying physical crops, converting inefficient formats, and reducing file sizes--often by 50-95% without visible quality loss.

Quick Start

# Analysis only (default - no changes, generates report)
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx"

# Optimize slides (most common)
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -OptimizeSlides

# Optimize with cropping
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -OptimizeSlides -CropSlides

# Full optimization (all slides, masters, layouts, with cropping)
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -All

# Batch process all PPTX files
Get-ChildItem *.pptx | .\Optimize-PptImages.ps1 -OptimizeSlides -CropSlides

Features

Core Optimization

Image resizing -- Reduces oversized images to match display size with configurable headroom (default 2x)
Physical cropping -- Materializes PowerPoint's soft crops into actual image files, removing hidden data
Format conversion -- Converts PNG->JPEG when transparency isn't needed; converts BMP, TIFF, GIF->JPEG/PNG
Unreferenced media cleanup -- Removes orphaned files from ppt/media/

Intelligent Processing

Transparency analysis -- Detects actual transparent pixels (not just alpha channel presence)
JPEG quality preservation -- Avoids recompression when source quality is already optimal
Color profile safety -- Images tagged with a non-sRGB ICC profile (such as AdobeRGB or ProPhoto) or in the CMYK colorspace are converted to sRGB before metadata is stripped, so colors render correctly in PowerPoint after optimization. Plain sRGB and untagged images are not affected.
Morph transition protection -- Preserves linked images across Morph slide pairs
Shared image awareness -- Uses maximum display size across all usages
Minimum savings threshold -- Skip optimizations below configurable savings percentage

Batch & Automation

Pipeline input -- Process multiple files via Get-ChildItem | .\Optimize-PptImages.ps1
Batch summary -- Aggregated statistics when processing multiple files
PassThru output -- Return result objects for programmatic use
Selective processing -- Include or exclude specific slides
WhatIf/Confirm support -- Preview changes before applying
Unused layout cleanup -- Removes slide layouts not referenced by any slide, plus masters that become completely unreferenced (opt-in via -CleanUnusedLayouts). Orphaned add-in parts (think-cell marker tags and OLE objects under ppt/tags/ppt/embeddings) that were referenced only by the removed layouts are automatically removed on every run once nothing references them.

Output & Reporting

Detailed console output -- Tag-based status indicators with progress
CSV report -- Per-image statistics for auditing and analysis; includes think-cell discovery so you can see which images are think-cell content and which slides depend on their layouts
think-cell summary -- When think-cell content is detected, a [THINK-CELL] console block shows total think-cell size, which layouts carry it, which slides use those layouts, and orphaned add-in parts
Output validation -- Optional post-repack validation via -ValidateOutput; reports Open XML SDK errors as warnings without aborting the run
Verbose mode -- Detailed logging with -Verbose

Requirements

Core Requirements

PowerShell: 7.0 or later (PowerShell Core). Windows PowerShell 5.1 is no longer supported.
ImageMagick: Version 7.x or later

Optional Requirements

DocumentFormat.OpenXml -- required only when using -ValidateOutput. Install via NuGet. Not needed for any other feature.

Platform Support

Platform	PowerShell Version	Status
Windows	PowerShell 7.0+	Supported
macOS	PowerShell 7.0+	Supported
Linux	PowerShell 7.0+	Supported

Installation

1. Install ImageMagick

Windows:

# Via Chocolatey
choco install imagemagick

# Or download from https://imagemagick.org/script/download.php#windows

macOS:

brew install imagemagick

Linux (Ubuntu/Debian):

sudo apt update && sudo apt install imagemagick

2. Clone the Repository

The tool is a PowerShell module spread across multiple files, so cloning the repository is required.

git clone https://github.com/Rouzax/Optimize-PptImages.git
cd Optimize-PptImages

Running the tool:

Option A -- run the entry-point script directly (same invocation as always):

.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -All

Option B -- import the module and call the exported function directly (useful for scripting and automation):

Import-Module ./Optimize-PptImages.psd1
Invoke-PptImageOptimization -InputPath "presentation.pptx" -All

Both options accept the same parameters and support pipeline input.

3. Verify Installation

magick --version
pwsh --version

Repository Layout

Path	Purpose
`Optimize-PptImages.ps1`	Thin entry-point script; imports the module and forwards all parameters
`Optimize-PptImages.psm1`	Module root; dot-sources the `src/` files
`Optimize-PptImages.psd1`	Module manifest
`src/`	Focused source files (Config, Classes, Common, ImageMagick, Xml, Relationships, Initialization, Structure, Scanning, Morph, Cropping, Optimization, LayoutCleanup, Cleanup, Validation, Reporting, Pipeline)
`src/Public/Invoke-PptImageOptimization.ps1`	The exported public function
`tests/`	Pester 5 test suite

Usage

Basic Examples

# Analysis only (default - generates report, no image changes)
.\Optimize-PptImages.ps1 -InputPath "MyPresentation.pptx"

# Optimize slides (resize and convert formats)
.\Optimize-PptImages.ps1 -InputPath "MyPresentation.pptx" -OptimizeSlides

# Optimize slides with cropping
.\Optimize-PptImages.ps1 -InputPath "MyPresentation.pptx" -OptimizeSlides -CropSlides

# Full optimization (everything enabled)
.\Optimize-PptImages.ps1 -InputPath "MyPresentation.pptx" -All

# Custom output location
.\Optimize-PptImages.ps1 -InputPath "input.pptx" -OutputPath "output.pptx" -OptimizeSlides

# With verbose logging
.\Optimize-PptImages.ps1 -InputPath "MyPresentation.pptx" -OptimizeSlides -CropSlides -Verbose

# Process only specific slides
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -IncludeSlides 1,5,10 -OptimizeSlides -CropSlides

# Exclude certain slides
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -ExcludeSlides 3,7 -OptimizeSlides

# Custom quality settings
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -OptimizeSlides -HeadroomFactor 1.5 -JpegQuality 90

# Require minimum 10% savings to apply changes
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -OptimizeSlides -MinSavingsPercent 10

# Remove unused layouts and masters
.\Optimize-PptImages.ps1 -InputPath "presentation.pptx" -OptimizeSlides -CropSlides -CleanUnusedLayouts

Batch Processing

# Process all PPTX files in current directory
Get-ChildItem *.pptx | .\Optimize-PptImages.ps1 -OptimizeSlides -CropSlides

# Process files matching pattern
Get-ChildItem -Path "C:\Presentations" -Filter "Report*.pptx" | .\Optimize-PptImages.ps1 -OptimizeSlides

# Get results for programmatic use
$results = Get-ChildItem *.pptx | .\Optimize-PptImages.ps1 -OptimizeSlides -PassThru
$results | Where-Object { $_.SavingsPercent -gt 50 } | Select-Object InputPath, SavingsPercent

# Preview what would be processed (WhatIf)
Get-ChildItem *.pptx | .\Optimize-PptImages.ps1 -OptimizeSlides -WhatIf

Batch Output Example:

============================================================
[STATS] BATCH SUMMARY
============================================================
Files processed: 5
  Successful: 5

Total savings:
  Original: 245.32 MB
  Optimized: 48.76 MB
  Saved: 196.56 MB (80.1%)

Interactive mode

-Interactive launches a guided wizard for a single file. Use it when you want to inspect what the script would do before committing to a run, or when you want to tune options without constructing a command line by hand.

.\Optimize-PptImages.ps1 -InputPath "deck.pptx" -Interactive

-Interactive cannot be combined with pipeline input or a batch input list. Attempting that combination raises an error.

What happens:

The script scans the file (read-only, no output written) and prints a findings summary split into two blocks: "Slides" and "Masters & layouts". Each block shows the usage and unique media counts, total media size, format breakdown, resize candidate count, PNG-to-JPEG conversion candidate count, and the top 5 oversized images by oversizing ratio. If more than 5 resize candidates exist, a "+N more" line follows the top-5 list. Source dimensions and opacity are resolved in parallel.
You answer a short sequence of questions:
- Operations: yes/no for each of: optimize slides (default ON), optimize masters/layouts, apply crops on slides, apply crops on masters/layouts, remove unused layouts/masters (all default OFF).
- Headroom factor: choose a labeled preset (Smallest file 1.5, Balanced 2.0, Print/HiDPI safe 3.0) or enter a custom value. Default is 2.0.
- JPEG quality: choose a labeled preset (Smaller 80, Balanced 90, High fidelity 95) or enter a custom value. Default is 95.
- Output path: press Enter to accept the derived default, or type a custom path.
- Advanced options (opt-in): if you answer yes, you can set transparency threshold, minimum savings percent, and slide include/exclude lists.
Any flags you pass alongside -Interactive pre-fill the matching defaults. For example, passing -CropSlides makes "Apply crops on slides?" default to YES.
The wizard displays the equivalent command line and offers four actions:
- [R]un now -- executes the operation immediately, reusing the scan already performed (no second extraction or scan).
- [C]opy & exit -- prints the equivalent command line and exits without writing any files.
- [E]dit an answer -- returns to a section menu (Operations, Headroom/Quality, Output path, Advanced) so you can revise a choice.
- [Q]uit -- exits without writing any files.

Parameters Reference

Parameter	Type	Default	Description
`InputPath`	String	Required	Path to input PPTX/POTX file. Accepts pipeline input.
`OutputPath`	String	`<n>.optimized.<ext>`	Path for optimized output file
`MagickPath`	String	Auto-detect	Path to ImageMagick `magick` executable
`OptimizeSlides`	Switch	`$false`	Resize and convert images in slides
`OptimizeMastersAndLayouts`	Switch	`$false`	Resize and convert images in master slides and layouts
`CropSlides`	Switch	`$false`	Apply physical crops to images in slides
`CropMastersAndLayouts`	Switch	`$false`	Apply physical crops to images in master slides and layouts
`CleanUnusedLayouts`	Switch	`$false`	Remove slide layouts not used by any slide and masters that become unreferenced. Not included in `-All`.
`ValidateOutput`	Switch	`$false`	Validate the repacked file with the Open XML SDK and report any errors. Non-fatal. Requires the optional DocumentFormat.OpenXml package. Not included in `-All`.
`All`	Switch	`$false`	Enable all optimization and cropping operations
`HeadroomFactor`	Decimal	`2.0`	Target resolution multiplier (0.5-4.0). 2.0 = 2x display size
`JpegQuality`	Int	`95`	JPEG quality for compression (1-100)
`TransparencyThresholdPercent`	Decimal	`0.1`	Minimum transparency % to keep PNG format (0.0-100.0)
`MinSavingsPercent`	Decimal	`0.0`	Minimum savings % required to apply optimization (0.0-50.0)
`IncludeSlides`	Int[]	None	Only process these slide numbers
`ExcludeSlides`	Int[]	None	Skip these slide numbers
`CsvReportPath`	String	`<o>.opt-report.csv`	Path for CSV report file
`PassThru`	Switch	`$false`	Return result object(s) to pipeline
`Interactive`	Switch	`$false`	Launch an interactive wizard to review findings and configure a run for a single file. Cannot be combined with pipeline or batch input.

Note: When using -IncludeSlides or -ExcludeSlides, all slides are still analyzed for correct shared image sizing and Morph detection--only the modification is filtered.

How It Works

Display Size vs Physical Size

PowerPoint stores the full original image regardless of how you resize it on the slide:

Physical Size: Actual pixel dimensions (e.g., 3840x2160px photo at 2 MB)
Display Size: How large it appears on slide (e.g., scaled to 400x225px)

If you display a 3840x2160px image at 400x225px, you're storing ~95% unnecessary data.

How PowerPoint Measures Size:

PowerPoint uses EMUs (English Metric Units): 914,400 EMUs = 1 inch. At 96 DPI, 9,525 EMUs = 1 pixel.

Cropping in PowerPoint

When you crop in PowerPoint's UI:

The entire original image remains embedded
Crop percentages are stored as XML (srcRect attributes)
Only the visible portion renders, but all data is stored

With -CropSlides, this script physically removes the cropped portions.

When the same source image is cropped with identical geometry on multiple shapes, the crop is materialized once and the resulting file is shared across all those shapes. Duplicated crops no longer inflate the output file.

Format Conversion

The script intelligently converts formats when beneficial:

Source Format	Conversion	Condition
PNG	-> JPEG	Transparency < threshold (default 0.1%)
BMP	-> JPEG/PNG	Based on transparency analysis
TIFF	-> JPEG/PNG	Based on transparency analysis
GIF (static)	-> JPEG/PNG	Based on transparency analysis
GIF (animated)	Skipped	Would break animation

Transparency Analysis: The script counts actual transparent pixels, not just alpha channel presence. A PNG with an alpha channel but no actual transparency gets converted to JPEG.

Color Profile Handling

When the optimize phase strips image metadata (EXIF, comments, and embedded profiles), it first checks the color profile of every image it processes:

Non-sRGB or CMYK: If an image carries a non-sRGB ICC profile (for example AdobeRGB, ProPhoto, or any custom print profile) or is in the CMYK colorspace, the script converts it to sRGB before stripping. This is done by passing -profile <bundled sRGB.icc> to ImageMagick immediately before -strip, so the color values in the output file match what you see in PowerPoint.
Plain sRGB or untagged: No conversion happens. The strip removes the profile tag as before. Colors are already in the display colorspace, so nothing changes visually.
Crop phase: The crop phase does not use -strip, so ICC profiles are preserved intact during cropping regardless of colorspace.

Most slide content (screen captures, web-downloaded photos) is already sRGB, so this change has no visible effect on those images.

Shared Images

PowerPoint can share a single media file across multiple slides. When you copy-paste an image between slides, they reference the same file.

Optimization Implications:

The script tracks the largest display size across all usages
All instances benefit from a single optimized file
Cropped shared images are handled carefully

Best Practice: Copy-paste images between slides (don't re-insert from disk) to leverage sharing.

Masters and Layouts

PowerPoint's three-tier hierarchy:

Slide Masters -- Top-level templates
Slide Layouts -- Layout templates based on masters
Slides -- Actual content based on layouts

By default, the script skips master/layout images to avoid widespread changes. Enable with:

-OptimizeMastersAndLayouts -- Resize and convert formats
-CropMastersAndLayouts -- Apply physical crops

Corporate templates often accumulate dozens or hundreds of unused layouts from merged or inherited slide masters. The -CleanUnusedLayouts switch removes layouts not referenced by any slide, along with any masters that have no remaining layouts. This is opt-in and not included in -All, since it reduces the layout gallery available when creating new slides.

Morph Transition Protection

The script detects Morph transitions and:

Identifies linked image pairs across consecutive slides
Prevents conflicting crops that would break animations
Ensures synchronized optimization of paired images

Understanding the Output

Console Output

[FILE] Processing file 1: Test Deck.pptx
[SCAN] Analyzing presentation structure...
   File: D:\Temp\PowerPoint\Test Deck.pptx
[STATS] Found 28 image usages
[STATS] Across 19 unique images
[LINK] Morph detection: 2 transition(s), 2 image pair(s) linked
[NOTE] Corrected illegal crop values for 'Picture 3' on Slide 20 (r:-12038->0, b:-182512->0)

[CROP] Processing image crops...
   [BLOCK] Morph crop conflict for 'Picture 3' across Slide 18 <-> 17 (skipping crop & optimization)
[STATS] Cropping phase complete: 6 cropped, 3 skipped

[PROC] Optimizing images...
   [SKIP] 'Picture 5' on Slide 3: has a soft crop -- add -CropSlides to materialize it first
[STATS] Optimization phase complete: 12 optimized, 10 skipped

[CLEAN] Cleaning up unreferenced media...
[CLEAN] Media files removed: 4

[PACK] Repacking presentation...
[OK] Repacked: 6557.56 KB

[DONE] Optimization Complete
[STATS] Images cropped: 6
[STATS] Images optimized: 11

[SIZE] File size:
  Original: 62.17 MB
  Optimized: 6.40 MB
  Saved: 55.76 MB (89.7%)

[SAVE] Saving output files...
[OUT] Output: D:\Temp\PowerPoint\Test Deck.optimized.pptx
[OUT] Report: D:\Temp\PowerPoint\Test Deck.optimized.opt-report.csv

By default, routine per-image detail ([OK], [CONV], [INFO] lines showing savings percentages) and per-image crop detail ([CROP] success lines) are suppressed. To see them, add -Verbose.

Items that require your attention still appear at normal verbosity. [SKIP] lines with a suggested flag (for example, "add -CropSlides") are shown in gray so you can see which images were skipped and why.

Phase-level headers ([PROC] Optimizing images...) and summary statistics ([STATS] Optimization phase complete: ...) are always shown.

Full per-image detail is always recorded in the CSV report regardless of verbosity level.

Status Indicators

Tag	Meaning
`[FILE]`	Processing file (batch mode)
`[SCAN]`	Analysis phase
`[STATS]`	Statistics/counts
`[LINK]`	Morph transition detection
`[CROP]`	Cropping operation
`[PROC]`	Optimization phase
`[CONV]`	Format conversion (PNG->JPEG, BMP->JPEG, etc.)
`[NOTE]`	Corrections (illegal crop values, removed no-op crop)
`[SKIP]`	Skipped operation
`[INFO]`	Info/notes (transparency detection, kept original)
`[BLOCK]`	Blocked operation (Morph conflict, safety)
`[CLEAN]`	Cleanup operation
`[PACK]`	Repacking presentation
`[CSV]`	Generating CSV report
`[OK]`	Success
`[DONE]`	Completion
`[SIZE]`	File size information
`[SAVE]`	File save operation
`[OUT]`	Output file paths
`[WARN]`	Warning
`[ERROR]`	Error

CSV Report

Each run generates a detailed CSV report with these columns:

Column	Description
`Location`	Where the image appears (e.g., "Slide 5", "Layout (slideLayout1.xml)")
`ContextType`	Type: Slide, Layout, Master, Notes, or Handout
`SlideNumber`	Slide number (0 for masters/layouts)
`SlideModified`	Whether the slide XML was modified
`ShapeName`	PowerPoint shape name (e.g., "Picture 3")
`IsThinkCell`	`Yes` if the shape is think-cell content (by shape name), else `No`
`UsedOnSlides`	For Layout/Master rows, the slide numbers that use this layout/master (`(none)` if unused); blank for Slide rows
`MediaPart`	Path of the media file inside the package (e.g., `ppt/media/image16.emf`)
`SourceWidthPx` / `SourceHeightPx`	Original image dimensions
`DisplayWidthPx` / `DisplayHeightPx`	Display dimensions on slide
`TargetWidthPx` / `TargetHeightPx`	Target dimensions after headroom factor
`OriginalFile`	Original media filename
`OptimizedFile`	Filename after optimization (may change if format converted)
`BeforeSizeBytes` / `AfterSizeBytes`	File sizes
`Savings`	Human-readable savings (e.g., "443.4 KB (93.0%)")
`HasSrcRect`	Whether PowerPoint crop was present
`CropApplied`	Whether physical crop was applied
`CropNormalized`	Whether illegal crop values were corrected
`CropRemovedNoOp`	Whether a no-op crop (>=98% visible) was removed
`SvgFallback`	Whether this is an SVG fallback image
`OptimizationStatus`	Result status (see below)
`WhyNotOptimized`	Reason if skipped
`HeadroomFactor`	Headroom factor used
`JpegQuality`	JPEG quality setting used
`SourceJpegQuality`	Original JPEG quality (for JPEG sources)
`TransparencyThresholdPercent`	Transparency threshold used
`EffectiveTransparencyPercent`	Actual transparency detected
`MinSavingsPercent`	Minimum savings threshold used
`ManualActionRequired`	Whether manual intervention is recommended
`ManualActionHint`	Suggested action

Sort Order: Rows are sorted by context type (Slides first, then Layouts, then Masters), then by slide number, then by layout/master number. This follows presentation order for easy reference.

Optimization Status Values:

Status	Description
`ConvertedPngToJpeg`	PNG converted to JPEG (no significant transparency)
`ConvertedToJpeg`	BMP/TIFF/GIF converted to JPEG
`ConvertedToPng`	TIFF/GIF converted to PNG (has transparency)
`OptimizedPngAlpha`	PNG optimized while preserving transparency
`OptimizedJpeg`	JPEG resized/recompressed
`NoChangeNeeded`	Already at target size
`Skipped_AlreadyOptimal`	Already at target size and quality
`Skipped_SlidesFlagMissing`	In slide; enable `-OptimizeSlides`
`Skipped_TemplatesFlagMissing`	In master/layout; enable `-OptimizeMastersAndLayouts`
`Skipped_CropNotMaterialized`	Has crop; enable `-CropSlides` or `-CropMastersAndLayouts`
`Skipped_MorphCropConflict`	Morph transition with conflicting crops
`Skipped_SvgFallback`	SVG fallback PNG; PowerPoint regenerates
`Skipped_UnsupportedFormat`	Unsupported format (EMF, WMF, SVG)
`Skipped_AnimatedGif`	Animated GIF; conversion would break animation
`Skipped_NoNetSavings`	No savings achieved or below threshold

Exit Codes

When running via Optimize-PptImages.ps1, the script reads the resolved exit code from the module and calls exit after the function returns, so the exit code propagates to the calling shell as normal.

When calling Invoke-PptImageOptimization directly after importing the module, the function does not call exit. The caller's process continues normally. The resolved exit code is stored in $script:LastFinalExitCode inside the module scope if you need to inspect it programmatically.

Code	Meaning
`0`	Success with changes applied
`1`	Error occurred
`2`	Success but no changes needed

Example Results

Analysis Only (Default)

.\Optimize-PptImages.ps1 -InputPath "Test Deck.pptx"

Metric	Value
Original	63.91 MB
Optimized	63.84 MB
Saved	75 KB (0.1%)
Images cropped	0
Images optimized	0

Savings from repack only. All images reported as skipped with hints for which flags to enable.

Optimize Slides (No Cropping)

.\Optimize-PptImages.ps1 -InputPath "Test Deck.pptx" -OptimizeSlides

Metric	Value
Original	63.91 MB
Optimized	56.59 MB
Saved	7.32 MB (11.5%)
Images cropped	0
Images optimized	5

Images with crops are skipped until -CropSlides is enabled.

Optimize and Crop Slides

.\Optimize-PptImages.ps1 -InputPath "Test Deck.pptx" -OptimizeSlides -CropSlides

Metric	Value
Original	63.91 MB
Optimized	34.90 MB
Saved	29.01 MB (45.4%)
Images cropped	5
Images optimized	9

Full Optimization (Including Masters/Layouts)

.\Optimize-PptImages.ps1 -InputPath "Test Deck.pptx" -All

Metric	Value
Original	63.91 MB
Optimized	6.56 MB
Saved	57.35 MB (89.7%)
Images cropped	6
Images optimized	12

Best Practices

Before Using This Script

Resize images before inserting -- Don't insert 4000x3000px photos for 400x300px display
Crop in image editor -- Don't rely on PowerPoint's soft crop
Choose right format -- Photos->JPEG, transparency->PNG, vectors->SVG
Copy-paste images -- Don't re-insert same image from disk (enables sharing)

When This Script Helps Most

Inheriting poorly-optimized presentations from others
Batch processing legacy presentations
Automated workflows where manual optimization isn't feasible
Recovering from "quick deadline" work
Applying accumulated soft crops

When NOT to Use

Print-quality presentations requiring high DPI (>220 PPI)
Intentional oversizing for zoom effects
Already well-optimized files
When you need original high-res images preserved

Limitations

What This Script Doesn't Handle

Item	Reason
Embedded videos	Only processes images
Embedded fonts	Not optimizable
SVG files	Vector format (no raster optimization)
EMF/WMF graphics	Vector formats (common in think-cell, Excel objects)
Audio files	Not processed
SmartArt	Rendered as vectors

Known Behaviors

SVG Fallbacks: PowerPoint auto-generates PNG fallbacks for SVGs. The script skips these as PowerPoint regenerates them.
Animated GIFs: Skipped to preserve animation.
Shared Image Sizing: Uses largest display size across all usages.
Illegal Crop Correction: Automatically corrects invalid (negative) crop values.
JPEG Quality Detection: Avoids recompression if source quality <= target.

Backup Recommendation

Always keep a backup. Optimization is lossy (especially JPEG compression). Original high-resolution images cannot be recovered.

Troubleshooting

"ImageMagick not found"

Install ImageMagick (see Installation)
Ensure magick is in your PATH
Restart terminal/PowerShell
Or use -MagickPath "C:\Path\To\magick.exe"

"File in use" / "Cannot open file"

Close PowerPoint before running
Ensure file isn't open elsewhere
Check file permissions

"Output file is in use"

The script checks file accessibility before processing. If locked:

Close the output file
Check console for temporary file locations

"Optimized file is corrupt"

Possible causes:

Unusual XML structure in original
Disk space issues
PowerPoint version incompatibility

Solutions:

Run with -Verbose for details
Check available disk space
Report issue with sample file

Unexpected File Size Increase

If optimized file is larger:

Original was already well-optimized
Images were at/below target sizes
Run with -Verbose to see what was skipped

Performance Notes

Processing Time

Deck Size	Typical Time
Small (10 slides, 5 images)	10-20 seconds
Medium (50 slides, 30 images)	1-2 minutes
Large (100 slides, 100 images)	3-5 minutes

Image probing (transparency analysis, JPEG quality detection), image cropping, and the ImageMagick resize/convert work all run in parallel across CPU cores. Decks with many images benefit the most from this; the improvement scales with core count.

Resource Usage

Peak memory: ~500MB-1GB depending on image sizes
Temp disk space: Up to 2x original file size
Cleanup: Automatic on completion or error

Reporting Issues

Include:

PowerShell version: $PSVersionTable
ImageMagick version: magick --version
Operating system
Sample PPTX (if possible)
Full console output with -Verbose

Acknowledgments

ImageMagick for high-quality image processing
PowerPoint Open XML format documentation

Remember: This script rescues bloated presentations and automates best practices--but the best optimization is careful design from the start. Size images appropriately, choose the right formats, crop before inserting, and reuse via copy-paste.

Name		Name	Last commit message	Last commit date
.github/workflows		.github/workflows
resources		resources
src		src
tests		tests
.gitignore		.gitignore
Optimize-PptImages.ps1		Optimize-PptImages.ps1
Optimize-PptImages.psd1		Optimize-PptImages.psd1
Optimize-PptImages.psm1		Optimize-PptImages.psm1
README.md		README.md

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