prsyahmi/wic_heic

How prsyahmi/wic_heic works

This is a Windows Imaging Component (WIC) codec that lets Windows imaging clients open HEIC files, with encoder support also implemented. The main workflow is WIC class activation, decoder initialization from an IStream, frame selection, then pixel and metadata access; encoding follows the corresponding WIC encoder and frame interfaces. The graph includes COM registration and the libheif boundary. Unsampled encoder internals are shown as components, but their specific call relationships are left unverified.

Main entry points: HeicBitmapDecoder.cpp WIC Decoder · ComFactory.cpp COM Class Factory · HeicBitmapEncoder.cpp WIC Encoder · dllmain.cpp Codec DLL

Components 15

COM Activation

Codec DLL wic_heic/dllmain.cpp
COM Class Factory wic_heic/ComFactory.cpp
COM Lifetime Counter wic_heic/ComCounter.cpp
Codec Registration wic_heic/UtlReg.cpp

HEIC Decoding

WIC Decoder wic_heic/HeicBitmapDecoder.cpp
HEIF Stream Reader wic_heic/HeifStreamReader.cpp
libheif Context
Decoded Frame wic_heic/HeicBitmapFrameDecode.cpp
Metadata Reader wic_heic/HeicMetadataBlockReader.cpp

HEIC Encoding

WIC Encoder wic_heic/HeicBitmapEncoder.cpp
Encode Frame wic_heic/HeicBitmapFrameEncode.cpp
HEIF Stream Writer wic_heic/HeifStreamWriter.cpp

Codec Support

Codec Exceptions wic_heic/HeicException.cpp

Other components

WIC Client
Windows Registry

Connections 16

WIC Client → Codec DLL: activates codec README.md
Codec DLL → COM Class Factory: requests class factory wic_heic/dllmain.cpp
Codec DLL → Codec Registration: registers codec wic_heic/dllmain.cpp
Codec Registration → Windows Registry: writes registrations
COM Class Factory → WIC Decoder: creates decoder wic_heic/ComFactory.cpp
COM Class Factory → WIC Encoder: creates encoder wic_heic/ComFactory.cpp
COM Class Factory → COM Lifetime Counter: tracks lifetime wic_heic/ComFactory.cpp
WIC Client → WIC Decoder: opens HEIC README.md
WIC Decoder → HEIF Stream Reader: reads stream wic_heic/HeicBitmapDecoder.cpp
WIC Decoder → libheif Context: loads context
WIC Decoder → Decoded Frame: creates frame wic_heic/HeicBitmapDecoder.cpp
Decoded Frame → libheif Context: decodes pixels wic_heic/HeicBitmapFrameDecode.cpp
Decoded Frame → Metadata Reader: creates query reader wic_heic/HeicBitmapFrameDecode.cpp
WIC Client → WIC Encoder: requests encoding
WIC Encoder → Encode Frame: creates frame
WIC Encoder → HEIF Stream Writer: writes output

Drawn by GitDiagram on November 9, 2026 from the repository's file tree, README and source files. Read as Markdown ·