Image MIME Reference
AVCS
AVC Image Sequence (HEIF Container)
image/avcs
VS
PaintShop Pro Image
image/x-paintshoppro
PaintShop-Pro-PSP
A complete technical comparison of AVC Image Sequence (HEIF Container) and PaintShop Pro Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | AVCS | PaintShop-Pro-PSP |
|---|---|---|
| Transparency (Alpha) | Yes | Yes |
| Animation Support | Yes | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | Yes | Yes |
| EXIF Metadata | Yes | Yes |
| ICC Color Profile | Yes | Yes |
AVC Image Sequence (HEIF Container)
image/avcs
Extension
.avcs.heifs
Container
HEIF / ISOBMFF (ISO/IEC 14496-12)
Compression
Lossy / Lossless
Algorithm
AVC (Advanced Video Coding / H.264)
Color Depth
8-bit, 10-bit, 12-bit
Developed by
Moving Picture Experts Group (MPEG) / ISO/IEC JTC 1
Released
2015
Magic Bytes
XX XX XX XX 66 74 79 70 61 76 63 73
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
Browser Support Comparison
| Browser | AVCS | PaintShop-Pro-PSP |
|---|---|---|
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✕ | ✕ |
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✕ | ✕ |
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✕ | ✕ |
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✕ | ✕ |
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✕ | ✕ |
AVCS
AVCS Strengths
- Efficiently stores bursts of images or animations utilizing inter-frame compression
- Leverages the highly compatible and widely hardware-accelerated AVC (H.264) codec
- Robust HEIF container supports extensive metadata, alpha channels, and depth maps
Limitations
- Zero native support in web browsers
- Largely superseded in efficiency by newer sequence formats like HEICS (HEVC) or Animated AVIF (AV1)
- Complicated container structure requires specialized parsing libraries
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
When to choose which format
AVCS
Use AVCS when…
- Burst Photography
- Short Animations
- Camera Capture
- Archival Storage
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)