packPNG v1.9

Lossless PNG / APNG / JNG / MNG recompressor. Byte-exact, reversible to the original file (verified via SHA-256).

Highlights

• New default backend (tovyCIP): preflate undoes the deflate byte-exact, then WebP-lossless stores the image → ≈ −54% on real PNGs with fast decode (~40–90 ms/file).
• -fast keeps the old kanzi+zstd backend for max speed; -preflate-max adds kanzi-TPAQX for extreme ratio.
• MNG support (Level A): whole-file preflate container with a store-raw fallback so output never bloats. The Network Graphics family is now complete: PNG / APNG / JNG / MNG.
• Self-contained build: all deps vendored; make builds the 100%-autonomous Linux static + Windows full binaries.

v2 magic naming

Every output magic spells out its backend (this drops pre-2.0 backward compat for the solid backends; 2.0 will freeze the format):

Magic	Expansion	Mode
TCIP	Tovy Compresor de Imágenes PNG	default (preflate + WebP-lossless)
TVCP	Tovy Veloz Compresor PNG	-fast (kanzi + zstd)
TMCP	Tovy Máximo Compresor PNG	-preflate-max (kanzi-TPAQX)
TCIJ	Tovy Compresor de Imágenes JNG	JNG inputs
TCIM	Tovy Compresor de Imágenes MNG	MNG inputs

Note the swap: TCIP now means the preflate default (it was the kanzi backend in v1.x, now TVCP).

Downloads

• Linux x86-64 (static, dependency-free): packPNG-linux-x86_64-static-v1.9
• Windows x86-64 (mingw, OS DLLs only): packPNG-windows-x86_64-full-v1.9.exe

SHA-256

6418f485943297a1397040a8d11563e4f2a69a14654b9e353c11db11bd789567  packPNG-linux-x86_64-static-v1.9
d1f2f8b94b082391cf915f1ba398b419bf4c564a9b207cefb8533939d962daf7  packPNG-windows-x86_64-full-v1.9.exe

The Windows .exe is unsigned; some AVs may flag it as a generic heuristic (false positive). Verify the SHA-256 or build from source.