Library for manipulating PNG images

Current versions

libpng requires the following formula to be installed:
xz 5.2.3 General-purpose data compression with high compression ratio

Reverse dependencies

The following formulae require libpng to be installed:
fox 1.6.51 Toolkit for developing Graphical User Interfaces easily.
grace 5.1.25
atpdec 1.7
php55 5.5.38_12 PHP Version 5.5
php53 5.3.29_8 PHP Version 5.3
php54 5.4.45_7 PHP Version 5.4
sdl_image 1.2.12_7 Image file loading library
fig2dev 3.2.6a_1 Translates figures generated by xfig to other formats
libkate 0.4.1_1 Overlay codec for multiplexed audio/video in Ogg
libsvg-cairo 0.1.6_2 SVG rendering library using Cairo
ufraw 0.22_2 Unidentified Flying RAW: RAW image processing utility
mozjpeg 3.2 Improved JPEG encoder
libbpg 0.9.7_1 Image format meant to improve on JPEG quality and file size
librasterlite 1.1g_3 Library to store and retrieve huge raster coverages
grace 5.1.25_2 WYSIWYG 2D plotting tool for X11
guetzli 1.0.1 Perceptual JPEG encoder
scale2x 3.1 Real-time graphics effect
dvdauthor 0.7.2 DVD-authoring toolset
qrencode 4.0.0 QR Code generation
pngnq 1.1_1 Tool for optimizing PNG images
neopop-sdl 0.2 NeoGeo Pocket emulator
openslide 3.4.1_3 C library to read whole-slide images (a.k.a. virtual slides)
imageworsener 1.3.2_1 Utility and library for image scaling and processing
fs-uae 2.8.3 Amiga emulator
xu4 1.0beta4+r3088 Remake of Ultima IV
teem 1.11.0 Libraries for scientific raster data
openmsx 0.14.0 MSX emulator
dosbox-x 0.801_1 DOSBox with accurate emulation and wide testing
mupen64plus 2.5 Cross-platform plugin-based N64 emulator
ffmpegthumbnailer 2.2.0_1 Create thumbnails for your video files
webalizer 2.23-08_1 Web server log file analysis
blat 36 Genomic sequence search tool
visp 3.0.1_4 Visual Servoing Platform library
devil 1.8.0_1 Cross-platform image library
jbig2dec 0.14 JBIG2 decoder and library (for monochrome documents)
libagar 1.5.0_1 Cross-platform GUI toolkit
nazghul 0.7.1 Computer role-playing game engine
ploticus 2.42_1 Scriptable plotting and graphing utility
synfig 1.0.2_2 Command-line renderer
rlvm 0.14_3 RealLive interpreter for VisualArts games
apng2gif 1.8 Convert APNG animations into animated GIF format
gif2png 2.5.11 Convert GIFs to PNGs
zint 2.6.2 Barcode encoding library supporting over 50 symbologies
swfmill 0.3.6 xml2swf and swf2xml processor
simutrans 120.1.3 Transport simulator
webp 0.6.1 Image format providing lossless and lossy compression for web images
ucsc-genome-browser 338 Mirror of the UCSC Genome Browser
ome-files 0.5.0 Open Microscopy Environment (OME) File scientific image I/O library
fuse-emulator 1.5.0 Free Unix Spectrum Emulator
sile 0.9.5-alpha_3 Modern typesetting system inspired by TeX
mapcrafter 2.4_2 Minecraft map renderer
enblend-enfuse 4.2_3 Combines images that overlap
astrometry-net 0.73 Automatic identification of astronomical images
insighttoolkit 4.13.0 ITK is a toolkit for performing registration and segmentation
sumo 0.32.0 Simulation of Urban Mobility
fontforge 20170731_2 Command-line outline and bitmap font editor/converter
ttfautohint 1.8.1 Auto-hinter for TrueType fonts
visp 3.1.0 Visual Servoing Platform library
blastem 0.5.1 Fast and accurate Genesis emulator
php70 7.0.27_19 PHP Version 7.0
grib-api 1.25.0 Encode and decode grib messages (editions 1 and 2)
povray Persistence Of Vision RAYtracer (POVRAY)
php56 5.6.33_9 PHP Version 5.6
freetype 2.9 Software library to render fonts
lensfun 0.3.2_2 Remove defects from digital images
scummvm 2.0.0 Graphic adventure game interpreter
sdl2_image 2.0.2 Library for loading images as SDL surfaces and textures
mapnik 3.0.18 Toolkit for developing mapping applications
argyll-cms 2.0.0_1 ICC compatible color management system
rgbds 0.3.5 Rednex GameBoy Development System
fizmo 0.8.5_1 Z-Machine interpreter
mgba 0.6.1_2 Game Boy Advance emulator
php71 7.1.14_25 PHP Version 7.1
php72 7.2.2_13 PHP Version 7.2
icoutils 0.32.2 Create and extract MS Windows icons and cursors
libbitcoin 3.5.0 Bitcoin Cross-Platform C++ Development Toolkit
vips 8.6.2 Image processing library
fltk 1.3.4-2 Cross-platform C++ GUI toolkit
gegl 0.3.28 Graph based image processing framework
graphicsmagick 1.3.28_1 Image processing tools collection
mldonkey 3.1.6_2 OCaml/GTK client for the eDonkey P2P network
sane-backends 1.0.27_4 Backends for scanner access
io 2017.09.06 Small prototype-based programming language
qemu 2.11.1 x86 and PowerPC Emulator
leptonica 1.75.3 Image processing and image analysis library
netpbm 10.73.18 Image manipulation
chocolate-doom 3.0.0 Accurate source port of Doom
imagemagick@6 6.9.9-35 Tools and libraries to manipulate images in many formats
hatari 2.1.0 Atari ST/STE/TT/Falcon emulator
stella 5.1.1 Atari 2600 VCS emulator
flif 0.3 Free Loseless Image Format

Recent formula history

ilovezfs Use “squiggly” heredocs.
Viktor Szakats libpng: secure url(s)
ilovezfs libpng 1.6.34
ilovezfs libpng 1.6.32
ilovezfs libpng 1.6.31

Formula code at GitHub