Thumbwright 0.1.3: HEIC without Microsoft's codecs

Thumbwright 0.1.3: HEIC photos without Microsoft's codecs

Download: Thumbwright-0.1.3-x64.msi below (signed). Or choco upgrade thumbwright.

What you'll notice

• iPhone and Android HEIC photos now show thumbnails out of the box. You no longer need Microsoft's HEIF and HEVC extensions from the Store. Thumbwright reads .heic, .heif, .hif, .heics and .heifs itself, using open-heic, a new open-source decoder written for this.
• Fast: a phone photo's thumbnail takes about a tenth of a second, because Thumbwright uses the small preview stored inside the file.
• Converting works too: right-click a HEIC, choose Convert, and get a JPEG or PNG without installing anything.
• Live Photos (.livp) use the same decoder.

Good to know

• Portrait-mode cutouts with transparency show on an opaque background for now.
• If a file uses a variant the built-in decoder can't read, Thumbwright falls back to Windows' own codecs when you have them installed.
• AVIF still needs Microsoft's free AV1 extension.

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Technical changes

Changed

• HEIC and HEIF thumbnails and conversions no longer need Microsoft's Store codecs.
  .heic, .heif, .hif, .heics and .heifs (iPhone, Android and camera photos: HEVC
  stills, tiled grids, embedded thumbnails, rotation and mirroring, 8/10-bit) are decoded by
  open-heic, a pure-Rust reader (MIT OR Apache-2.0,
  forbid(unsafe_code)) pinned by commit. It runs in the isolated worker, because its HEVC
  decoder is young and panics on corrupt streams; the shell asks for the file's embedded
  thumbnail first, which takes milliseconds. Windows' own codecs stay as the fallback for what
  open-heic cannot read (JPEG-coded HEIF items, overlays, 4:2:2/4:4:4 chroma), and a JPEG
  saved under a .heic name is decoded in-process. Live Photo (.livp) stills use the same
  path. Known limit: the separate transparency plane Apple writes for portrait-mode cutouts is
  not applied, so those images show opaque. AVIF and AVCI are unchanged (Windows codecs only).
• twctl doctor now says HEIC/HEIF thumbnails are built in and lists the Store HEIF and HEVC
  extensions as an optional fallback.
• The format table no longer lists an OS codec for the HEIC family.

SHA-256

ac47dfce064a16e62affff3f44ac1adfb52e777dffea6d0ef1d43e742a31ea67  Thumbwright-0.1.3-x64.msi
563c68ac969f3b81b17e538d3514a3bb68188eb85e8a214bd0a9f5e347e5486f  twctl.exe
96ea1fbb6127b973b2cf527258ce1601b4adc30881ece967f09ab120e64e234e  tw-worker.exe
d6ed584d0ee7f8106c0352927e47695cea75daa402c119f35b301dbb84e840f1  thumbwright_shell.dll
4ea51f4f7270e6f55e36e2dcec55ec94090bf192687306de9b3179c33235d144  thumbwright-settings.exe
f7a2514bc0f836f67ebf9a31e3b6ae3a89db0fc4d61b1cd99b91fe1847fb6dcd  Thumbwright.msix