Announcing libpng version 1.6.49 + pre-announcing libpng version 2

[ctruta]

Motto: "hello, world!"
-- Brian Kernighan, BCPL programmer, circa 1972

So... hello, world!

In observance of today's date (Friday, 13th of June, 2025), and in defiance of paraskevidekatriaphobia, I am super-happy to announce the release of libpng-1.6.49 which happened yesterday, the merging of all changes into libpng-1.8 which happened today, and the renaming of libpng-1.8 to libpng-2 which will happen tomorrow.

libpng-1.6.49 is the latest, greatest and stable-est of all libpng releases. This is the first libpng version in which the delta-filtering implementation is SIMD-optimized for the RISC-V architecture -- specifically for the RV64GV variant of the RISC-V ISA. I would like to thank Manfred Schlägl, Dragoș Tiselice and Filip Wasil, not only for their exceptional work, but also for their exceptional patience: according to my records, Manfred submitted the first pull request back in September 2021(!!)

https://github.com/pnggroup/libpng/tree/v1.6.49/
https://sourceforge.net/projects/libpng/files/libpng16/1.6.49/
https://raw.githubusercontent.com/pnggroup/libpng/v1.6.49/ANNOUNCE

Next in line is libpng version 1.8, which is about to have an ever shorter development life than its predecessor version 1.7.

Tomorrow I will rename the v1.8 development branch to v2. And not only that, but also, I want to make certain C language and library features mandatory, from C99 onwards. And not only that, but also, I want to make certain zlib library features mandatory, from zlib-1.2.8 (or maybe from zlib-1.2.11) onwards. And not only that, but also, I would like to invite everyone interested to discuss and debate what to do and what not to do, either on our group's png-implement mailing list or on our group's discussion forum at https://github.com/pnggroup/libpng/discussions/

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In the good old tradition of file authentication, here are the SHA-2-256 checksums of the published files:

d173dada6181ef1638bcdb9526dd46a0f5eee08e3be9615e628ae54f888f17f9  libpng-1.6.49.tar.gz
43182aa48e39d64b1ab4ec6b71ab3e910b67eed3a0fff3777cf8cf40d6ef7024  libpng-1.6.49.tar.xz
74129e2c3fdcbcc6a7a0bca21e394597ae30593fe948235808790d4d9db120e2  lpng1649.7z
84d82e24e8436b05f2e1a5fba218cbd0a017c27f1f735151f257277409a0809c  lpng1649.zip

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Sincerely,
Cosmin