Free webp to jpg
EN
Image MIME Reference
PaintShop-Pro-PSP

PaintShop Pro Image

image/x-paintshoppro
VS

Portable Graymap

image/x-portable-graymap
PGM

A complete technical comparison of PaintShop Pro Image and Portable Graymap — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.

Equal browser support

Feature Support

Feature PaintShop-Pro-PSP PGM
Transparency (Alpha) Yes ✕ No
Animation Support ✕ No ✕ No
Progressive Loading ✕ No ✕ No
HDR Support Yes Yes
EXIF Metadata Yes ✕ No
ICC Color Profile Yes ✕ No
PaintShop Pro Image
image/x-paintshoppro
Extension
.psp.pspimage.tub.pat
Container PSP Chunk-based Format
Compression Uncompressed / RLE (Run-Length Encoding) / LZ77
Algorithm
RLELZ77
Color Depth 8-bit (Indexed), 16-bit (Grayscale), 24-bit (RGB), 32-bit (RGBA), 48-bit (High Color)
Developed by Jasc Software / Corel Corporation (Alludo)
Released 1990
Magic Bytes
7E 42 4B 00
Full PaintShop-Pro-PSP reference →
Portable Graymap
image/x-portable-graymap
Extension
.pgm
Container Netpbm
Compression Uncompressed
Algorithm
None
Color Depth 8-bit (Grayscale), 16-bit (Grayscale)
Developed by Jef Poskanzer (Netpbm Project)
Released 1988
Magic Bytes
50 32 (ASCII) or 50 35 (Binary)
Full PGM reference →

Browser Support Comparison

Browser PaintShop-Pro-PSP PGM
Chrome Chrome
✕ ✕
Firefox Firefox
✕ ✕
Safari Safari
✕ ✕
Edge Edge
✕ ✕
IE IE (Legacy)
✕ ✕
PaintShop-Pro-PSP

PaintShop-Pro-PSP Strengths

  • Provides robust, non-destructive editing capabilities with full support for vector layers, adjustment layers, and layer blend modes
  • Historically offered a highly capable and affordable alternative to Adobe Photoshop's PSD format for Windows users
  • Features proprietary support for 'Picture Tubes' (.tub), a unique brush technology that paints sequential or random raster objects along a path
Limitations
  • Deeply proprietary format tied exclusively to the Corel/Alludo ecosystem
  • Third-party software support (like GIMP or ImageMagick) is often limited to parsing older .psp files, frequently failing to render complex layers in modern .pspimage files
  • No support in modern web browsers; must be exported to a flattened web format (JPEG/PNG) for online viewing
PGM

PGM Strengths

  • Extremely simple format allows custom parsers to be written from scratch in minimal time
  • Supports 16-bit precision, making it highly valuable for scientific, medical, and height-map data where 8-bit precision is insufficient
  • ASCII encoding ('P2') allows manual editing and visual inspection of pixel values directly within a text editor
Limitations
  • Strictly limited to grayscale; cannot display color
  • Lack of compression results in massive file sizes, making it entirely impractical for web delivery or consumer storage
  • Does not support alpha transparency or modern metadata structures

When to choose which format

PaintShop-Pro-PSP
Use PaintShop-Pro-PSP when…
  • PaintShop Pro Multi-layer Project Archival
  • Digital Art and Photo Retouching
  • Picture Tubes (.tub) and Custom Patterns (.pat)
PGM
Use PGM when…
  • Computer Vision and Machine Learning Pre-processing
  • Scientific and Medical Image Processing
  • Unix/Linux Command-Line Image Pipelines

More comparisons

PaintShop-Pro-PSP vs ACES → PGM vs ACES → PaintShop-Pro-PSP vs APNG → PGM vs APNG → PaintShop-Pro-PSP vs AVCI → PGM vs AVCI → PaintShop-Pro-PSP vs AVCS → PGM vs AVCS → PaintShop-Pro-PSP vs AVIF → PGM vs AVIF → All comparisons →
Share this comparison