DOTM to HEIF Converter

HEIF (High Efficiency Image File Format) is a container format for images and image sequences standardized by the Moving Picture Experts Group as ISO/IEC 23008-12, first published in 2015. HEIF is built on the ISO Base Media File Format (ISOBMFF, the same container used for MP4 video), providing a flexible structure that can hold single images, image collections, image sequences (like animations or bursts), and derived images with non-destructive editing operations. The container is codec-agnostic — while the most common implementation pairs HEIF with HEVC/H.265 compression (branded as HEIC by Apple), the standard also accommodates AV1 compression (creating the AVIF variant), H.266/VVC, and other future codecs. HEIF supports features that JPEG lacks: 10-bit and 12-bit color depth, wide color gamuts (Display P3, BT.2020), lossless compression, alpha transparency, depth maps, thumbnail images, and Exif/XMP metadata — all within a single file. Auxiliary image items can store computational photography data like depth maps, HDR gain maps, and semantic segmentation masks. One advantage is the format's future-proof architecture: by separating the container from the codec, HEIF can adopt newer, more efficient compression technologies without changing the file structure, metadata handling, or application-level APIs. The substantial compression improvement over JPEG is another core strength — HEVC-based HEIF typically achieves 40-50% file size reduction compared to JPEG at the same visual quality, beneficial for storage and bandwidth. HEIF is supported by Apple's ecosystem (iOS, macOS), Windows 10/11, Android 10+, GIMP, ImageMagick, and Adobe products.