# libvips : an image processing library [![CI](https://github.com/libvips/libvips/workflows/CI/badge.svg)](https://github.com/libvips/libvips/actions) [![Fuzzing Status](https://oss-fuzz-build-logs.storage.googleapis.com/badges/libvips.svg)](https://bugs.chromium.org/p/oss-fuzz/issues/list?sort=-opened&can=2&q=proj:libvips) [![Coverity Status](https://scan.coverity.com/projects/6503/badge.svg)](https://scan.coverity.com/projects/jcupitt-libvips) [![Gitter](https://badges.gitter.im/libvips/devchat.svg)](https://gitter.im/libvips/devchat?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge) # Introduction libvips is a [demand-driven, horizontally threaded](https://github.com/libvips/libvips/wiki/Why-is-libvips-quick) image processing library. Compared to similar libraries, [libvips runs quickly and uses little memory](https://github.com/libvips/libvips/wiki/Speed-and-memory-use). libvips is licensed under the [LGPL 2.1+](https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html). It has around [300 operations](https://libvips.github.io/libvips/API/current/func-list.html) covering arithmetic, histograms, convolution, morphological operations, frequency filtering, colour, resampling, statistics and others. It supports a large range of [numeric types](https://libvips.github.io/libvips/API/current/VipsImage.html#VipsBandFormat), from 8-bit int to 128-bit complex. Images can have any number of bands. It supports a good range of image formats, including JPEG, JPEG2000, JPEG-XL, TIFF, PNG, WebP, HEIC, AVIF, FITS, Matlab, OpenEXR, PDF, SVG, HDR, PPM / PGM / PFM, CSV, GIF, Analyze, NIfTI, DeepZoom, and OpenSlide. It can also load images via ImageMagick or GraphicsMagick, letting it work with formats like DICOM. It comes with bindings for [C](https://libvips.github.io/libvips/API/current/using-from-c.html), [C++](https://libvips.github.io/libvips/API/current/using-from-cpp.html), and the [command-line](https://libvips.github.io/libvips/API/current/using-cli.html). Full bindings are available for : | Language | Binding | |---|---| | Ruby | [ruby-vips](https://rubygems.org/gems/ruby-vips) | | Python | [pyvips](https://pypi.python.org/pypi/pyvips) | | PHP | [php-vips](https://github.com/libvips/php-vips) | | C# / .NET | [NetVips](https://www.nuget.org/packages/NetVips) | | Go | [govips](https://github.com/davidbyttow/govips) | | Lua | [lua-vips](https://github.com/libvips/lua-vips) | | Crystal | [crystal-vips](https://github.com/naqvis/crystal-vips) | | Elixir | [vix](https://github.com/akash-akya/vix) | libvips is used as an image processing engine by: | | |---| | [sharp (on node.js)](https://www.npmjs.org/package/sharp) | | [bimg](https://github.com/h2non/bimg) | | [sharp for Go](https://github.com/DAddYE/vips) | | [Ruby on Rails](https://edgeguides.rubyonrails.org/active_storage_overview.html) | | [carrierwave-vips](https://github.com/eltiare/carrierwave-vips) | | [mediawiki](https://www.mediawiki.org/wiki/Extension:VipsScaler) | | [PhotoFlow](https://github.com/aferrero2707/PhotoFlow) | and others. The official libvips GUI is [nip2](https://github.com/libvips/nip2), a strange combination of a spreadsheet and a photo editor. # Install There are packages for most Unix-like operating systems, including macOS. Check your package manager. There are binaries for Windows in [releases](https://github.com/libvips/libvips/releases). The [libvips website](https://libvips.github.io/libvips) has [detailed install notes](https://libvips.github.io/libvips/install.html). # Building from source libvips uses the [Meson build system](https://mesonbuild.com), version 0.56 or later. Meson can use [`ninja`](https://ninja-build.org), Visual Studio or XCode as a backend, so you'll also need one of them. libvips must have `build-essential`, `pkg-config`, `libglib2.0-dev`, `libexpat1-dev`. See the **Dependencies** section below for a full list of the libvips optional dependencies. libvips uses the GObject introspection mechanism by default, so you'll need packages like `libgirepository1.0-dev`. Use `-Dintrospection=false` to disable introspection support. There are basic bash completions in `completions/`, see the README in there. ## Cheatsheet ``` cd libvips-x.y.x meson setup build --prefix /my/install/prefix cd build meson compile meson test meson install ``` Check the output of `meson setup` carefully and make sure it found everything you wanted it to find. Add arguments to `meson setup` to change the build configuration. - Add flags like `-Dnsgif=false` to turn libvips options on and off, see `meson_options.txt` for a list of all the build options libvips supports. - Add flags like `-Dmagick=disabled` to turn libvips dependencies on and off, see `meson_options.txt` and the list below for a summary of all the libvips dependencies. - Meson will do a debug build by default. Add `--buildtype release` for a release (optimised) build. - You might need to add `--libdir lib` on Debian if you don't want the arch name in the library path. - Add `--default-library static` for a static build. - Use eg. `CC=clang CXX=clang++ meson setup ...` to change compiler. - You can have many `build-dir`, pick whatever names you like, for example one for release and one for debug. There's a more comprehensive test suite you can run once libvips has been installed. Use `pytest` in the libvips base directory. ## Optional dependencies If suitable versions are found, libvips will add support for the following libraries automatically. Packages are generally found with `pkg-config`, so make sure that is working. ### libjpeg Anything that is compatible with the IJG JPEG library. Use `mozjpeg` if you can. Another option is `libjpeg-turbo`. ### libexif If available, libvips adds support for EXIF metadata in JPEG files. ### librsvg The usual SVG loader. If this is not present, vips will try to load SVGs via imagemagick instead. ### PDFium If present, libvips will attempt to load PDFs with PDFium. Download the prebuilt pdfium binary from: https://github.com/bblanchon/pdfium-binaries Untar to the libvips install prefix, for example: cd ~/vips tar xf ~/pdfium-linux.tgz Create a `pdfium.pc` like this (update the version number): VIPSHOME=/home/john/vips cat > $VIPSHOME/lib/pkgconfig/pdfium.pc << EOF prefix=$VIPSHOME exec_prefix=\${prefix} libdir=\${exec_prefix}/lib includedir=\${prefix}/include Name: pdfium Description: pdfium Version: 4290 Requires: Libs: -L\${libdir} -lpdfium Cflags: -I\${includedir} EOF If PDFium is not detected, libvips will look for `poppler-glib` instead. ### poppler-glib The Poppler PDF renderer, with a glib API. If this is not present, vips will try to load PDFs via imagemagick. ### cgif If available, libvips will save GIFs with [cgif](https://github.com/dloebl/cgif). If this is not present, vips will try to save gifs via imagemagick instead. ### libgsf-1 If available, libvips adds support for creating image pyramids with `dzsave`. ### libtiff The TIFF library. It needs to be built with support for JPEG and ZIP compression. 3.4b037 and later are known to be OK. ### fftw3 If libvips finds this library, it uses it for fourier transforms. ### lcms2 If present, `vips_icc_import()`, `vips_icc_export()` and `vips_icc_transform()` can be used to manipulate images with ICC profiles. ### libspng If present, libvips will load and save PNG files using libspng. If not, it will look for the standard libpng package. ### libimagequant, quantizr If one of these quantisation packages is present, libvips can write 8-bit palette-ised PNGs and GIFs. ### ImageMagick, or optionally GraphicsMagick If available, libvips adds support for loading and saving all libMagick-supported image file types. You can enable and disable load and save separately. Imagemagick 6.9+ needs to have been built with `--with-modules`. Most packaged IMs are, I think. If you are going to be using libvips with untrusted images, perhaps in a web server, for example, you should consider the security implications of enabling a package with such a large attack surface. ### pangocairo If available, libvips adds support for text rendering. You need the package pangocairo in `pkg-config --list-all`. ### orc-0.4 If available, vips will accelerate some operations with this run-time compiler. ### matio If available, vips can load images from Matlab save files. ### cfitsio If available, vips can load FITS images. ### libwebp If available, vips can load and save WebP images. ### libniftiio If available, vips can load and save NIfTI images. ### OpenEXR If available, libvips will directly read (but not write, sadly) OpenEXR images. ### OpenJPEG If available, libvips will read and write JPEG2000 images. ### libjxl If available, libvips will read and write JPEG-XL images. ### OpenSlide If available, libvips can load OpenSlide-supported virtual slide files: Aperio, Hamamatsu, Leica, MIRAX, Sakura, Trestle, and Ventana. ### libheif If available, libvips can load and save HEIC and AVIF images. Your libheif (in turn) needs to be built with the correct decoders and encoders. You can check with eg.: ``` $ pkg-config libheif --print-variables builtin_avif_decoder builtin_avif_encoder builtin_h265_decoder builtin_h265_encoder exec_prefix includedir libdir pcfiledir prefix ``` # Contributors ### Code Contributors This project exists thanks to all the people who contribute. ### Organizations We've had generous financial support from our sponsors. Thank you very much!