Supported Formats

ImageChunker supports a wide variety of image formats for both input and output.

Input Formats

ImageChunker can read the following formats:

Format	Extensions	Notes
JPEG	`.jpg`, `.jpeg`	Most common photo format
PNG	`.png`	Lossless with transparency
HEIC	`.heic`, `.heif`	Apple’s efficient format
TIFF	`.tiff`, `.tif`	Professional publishing
BMP	`.bmp`	Windows bitmap
GIF	`.gif`	First frame only
WebP	`.webp`	Modern web format
PDF	`.pdf`	First page only
SVG	`.svg`	Rasterized on import
RAW	Various	Via macOS RAW support

RAW Camera Formats

ImageChunker supports RAW files through macOS’s built-in camera support:

Manufacturer	Formats
Canon	`.cr2`, `.cr3`
Nikon	`.nef`, `.nrw`
Sony	`.arw`, `.sr2`
Fujifilm	`.raf`
Panasonic	`.rw2`
Olympus	`.orf`
Pentax	`.pef`
Adobe	`.dng`

Output Formats

ImageChunker can export to:

Format	Extension	Best For
PNG	`.png`	Screenshots, graphics, text
JPEG	`.jpg`	Photos, social media
HEIC	`.heic`	Apple devices, smaller files
PDF	`.pdf`	Contact sheets, printing

Format Comparison

Feature	PNG	JPEG	HEIC
Compression	Lossless	Lossy	Lossy
Transparency	Yes	No	Yes
File size	Large	Small	Smallest
Quality	Perfect	Configurable	Configurable
Compatibility	Universal	Universal	Apple/Modern

Format Details

PNG

Pros:

Lossless compression (no quality loss)
Supports transparency (alpha channel)
Best for text and sharp edges
Universal compatibility

Cons:

Larger file sizes
Slower to encode/decode
No progressive loading

When to use:

Screenshots with text
Graphics with solid colors
Images requiring transparency
Archival quality

JPEG

Pros:

Small file sizes
Configurable quality
Universal compatibility
Progressive loading support

Cons:

Lossy compression
No transparency
Artifacts at low quality
Poor for text/graphics

Quality Settings:

Quality	Use Case
60-70%	Web thumbnails
75-85%	Social media
85-90%	General use
90-95%	High quality
95-100%	Near-lossless

When to use:

Photos and continuous-tone images
Social media posts
Web content
When file size matters

HEIC

Pros:

Excellent compression (smaller than JPEG at same quality)
Supports transparency
Supports 16-bit color
HDR and wide color support

Cons:

Limited compatibility (mainly Apple)
Slower encoding
Some apps can’t open

When to use:

Apple-only workflows
Photos on iPhone/iPad
When storage is limited
Modern applications

PDF (Contact Sheets)

Create a PDF containing all chunks:

Options:

Grid layout: Chunks arranged in grid
Stacked layout: One chunk per page
With margins: Space around each chunk
Include metadata: Chunk numbers, dimensions

When to use:

Printing all chunks
Client review
Documentation
Archival purposes

Color Profiles

Supported Profiles

Profile	Purpose
sRGB	Web, general use
Display P3	Apple displays, HDR content
Adobe RGB	Print publishing
ProPhoto RGB	Professional photography

Profile Handling

Option	Behavior
Preserve	Keep original profile
Convert to sRGB	Best web compatibility
Remove	No embedded profile

Recommendations

Web/Social: Convert to sRGB
Print: Preserve or Adobe RGB
Apple devices: Display P3 or sRGB

Bit Depth

ImageChunker preserves bit depth when possible:

Source	PNG Output	JPEG Output	HEIC Output
8-bit	8-bit	8-bit	8-bit
16-bit	16-bit	8-bit	10-bit
32-bit (HDR)	16-bit	8-bit	10-bit

Transparency

Alpha Channel Support

Format	Input	Output
PNG	✓	✓
HEIC	✓	✓
JPEG	✗	✗

Background Fill

When exporting transparency to JPEG:

Default: White background
Configurable: Any solid color
Option: Checkerboard preview

Metadata

Supported Metadata Types

Type	PNG	JPEG	HEIC
EXIF	Partial	Full	Full
IPTC	No	Yes	Yes
XMP	Yes	Yes	Yes
GPS	Yes	Yes	Yes
ICC Profile	Yes	Yes	Yes

Metadata Options

Setting	Behavior
Preserve All	Keep all original metadata
Strip GPS	Remove location data only
Strip All	Remove all metadata

Resolution

DPI/PPI Settings

Setting	Use Case
72 DPI	Screen display
150 DPI	General print
300 DPI	High-quality print
600 DPI	Professional print

Resolution Handling

Preserve: Keep original DPI
Set custom: Override DPI value
Auto: 72 DPI for web sizes, 300 for print

Maximum Dimensions

ImageChunker handles very large images:

Metric	Limit
Maximum width	65,535 px
Maximum height	65,535 px
Maximum pixels	268 million
Maximum file size	2 GB

For extremely large images:

Enable streaming mode in Settings
Use sequential batch processing
Consider reducing input resolution first

Troubleshooting

”Unsupported format” Error

Check file extension is correct
Try renaming with proper extension
Open in Preview to verify format
Re-export from original software

Color Looks Wrong

Check color profile in original
Try “Convert to sRGB” option
View in color-managed application
Export with embedded profile

Transparency Lost

Ensure output format supports alpha
Use PNG or HEIC, not JPEG
Check “Preserve transparency” is enabled

File Too Large

Use JPEG or HEIC instead of PNG
Reduce quality setting
Scale down output dimensions
Remove metadata