# Reworking OpenCV's Mat with memory-mapped files: solving the problem of large images that don't fit in memory

- Source: Guyuehome
- Published: 2026-10-12T04:59:00.000Z
- RoboHot: https://robohot.news/en/items/bc1plz947a0pty0wuvx38544t
- Original: https://www.guyuehome.com/detail?id=2077987193780989953

## Summary

Reworking OpenCV's Mat through memory-mapped files lets large images that don't fit in memory still be accessed through the Mat interface, with data still pointing to a contiguous uchar* in memory. Below the threshold, native heap allocation is still used and performance is unaffected; only genuinely large images switch paths, transparently to upper-layer callers.