Image MIME Reference
PCO-B16
PCO B16 Image
image/vnd.pco.b16
VS
Apple PICT Image
image/x-pict
PICT
A complete technical comparison of PCO B16 Image and Apple PICT Image — covering compression, feature support, browser compatibility, magic bytes, and when to choose each format.
Equal browser support
Feature Support
| Feature | PCO-B16 | PICT |
|---|---|---|
| Transparency (Alpha) | ✕ No | Yes |
| Animation Support | ✕ No | ✕ No |
| Progressive Loading | ✕ No | ✕ No |
| HDR Support | ✕ No | ✕ No |
| EXIF Metadata | ✕ No | ✕ No |
| ICC Color Profile | ✕ No | ✕ No |
PCO B16 Image
image/vnd.pco.b16
Extension
.b16
Container
PCO B16 Binary Container
Compression
Uncompressed (Raw Sensor Data)
Algorithm
None
Color Depth
16-bit (Monochrome or Bayer Raw Color)
Developed by
PCO AG (Excelitas PCO GmbH)
Released
Early 2000s
Magic Bytes
50 43 4F 2D
Apple PICT Image
image/x-pict
Extension
.pict.pct.pic
Container
QuickDraw Metafile
Compression
Uncompressed / Run-Length Encoding (RLE) / QuickTime Compressors (JPEG, SMC)
Algorithm
Apple PackBits (RLE)QuickTime Image Compression Manager (ICM)
Color Depth
1-bit, 2-bit, 4-bit, 8-bit (Indexed), 16-bit (High Color), 24-bit (True Color), 32-bit (RGBA)
Developed by
Apple Computer, Inc.
Released
1984
Magic Bytes
None (Requires offset parsing, e.g., 00 11 02 FF at byte 522)
Browser Support Comparison
| Browser | PCO-B16 | PICT |
|---|---|---|
Chrome
|
✕ | ✕ |
Firefox
|
✕ | ✕ |
Safari
|
✕ | ✕ |
Edge
|
✕ | ✕ |
IE (Legacy)
|
✕ | ✕ |
PCO-B16
PCO-B16 Strengths
- Preserves exact, uncompressed 16-bit raw sensor data, which is critically important for accurate scientific measurements, fluorescence microscopy, and photometry
- The simple, linear struct header is highly predictable and easy to parse in custom Python, MATLAB, or C++ scripts for researchers building bespoke pipelines
Limitations
- Generates massive file sizes due to the complete lack of image compression [1.3.1]
- Completely unsupported by standard operating systems, web browsers, and consumer image editing suites
- Strictly tied to the hardware and software ecosystems of a single camera manufacturer
PICT
PICT Strengths
- Incredibly versatile for its time, allowing a single file to cleanly scale text and vector shapes while simultaneously housing raster photos
- Served as the flawless universal clipboard format for the classic Mac OS, enabling seamless copy/pasting between wildly different applications
Limitations
- Deeply tied to Apple's legacy QuickDraw graphics architecture, making it exceptionally difficult to write accurate third-party parsers on modern operating systems
- Lack of a standard magic header makes file detection unreliable without seeking 522 bytes deep into the file
- Completely unsupported in modern web environments and discontinued by Apple itself
When to choose which format
PCO-B16
Use PCO-B16 when…
- Microscopy and Life Sciences
- High-Speed Camera Recording
- Machine Vision and Industrial Inspection
- Scientific Photometry
PICT
Use PICT when…
- Classic Mac OS Clipboard Data
- Legacy Macintosh Desktop Publishing (Aldus PageMaker, QuarkXPress)
- 1980s/1990s Digital Clip Art