John Cupitt 63d2da6a1d note JPEG-XL in README.md

2021-04-18 17:57:09 +01:00

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libvips : an image processing library

Introduction

libvips is a demand-driven, horizontally threaded image processing library. Compared to similar libraries, libvips runs quickly and uses little memory. libvips is licensed under the LGPL 2.1+.

It has around 300 operations covering arithmetic, histograms, convolution, morphological operations, frequency filtering, colour, resampling, statistics and others. It supports a large range of numeric types, 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, C++, and the command-line. Full bindings are available for Ruby, Python, PHP, C# / .NET, Go, and Lua. libvips is used as an image processing engine by sharp (on node.js), bimg, sharp for Go, Ruby on Rails, carrierwave-vips, mediawiki, PhotoFlow and others. The official libvips GUI is 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.

The libvips website has detailed install notes.

Building libvips from a source tarball

We keep pre-baked tarballs in releases.

Untar, then in the libvips directory you should just be able to do:

./configure

Check the summary at the end of configure carefully. libvips must have build-essential, pkg-config, libglib2.0-dev, libexpat1-dev.

You'll need the dev packages for the file format support you want. For basic jpeg and tiff support, you'll need libtiff5-dev, libjpeg-turbo8-dev, and libgsf-1-dev. See the Dependencies section below for a full list of the things that libvips can be configured to use.

Once configure is looking OK, compile and install with the usual:

make
sudo make install

By default this will install files to /usr/local.

Testing

Run the test suite with:

make check

Run a specific test with:

pytest test/test-suite/test_foreign.py -k test_tiff

Building libvips from git

Clone the latest sources with:

git clone git://github.com/libvips/libvips.git

Building from git needs more packages -- you'll need at least gtk-doc and gobject-introspection, see the dependencies section below. For example:

brew install gtk-doc

Then generate the build system with:

./autogen.sh --prefix=/home/john/vips

Debug build:

CFLAGS="-g -Wall" CXXFLAGS="-g -Wall" \
  ./configure --prefix=/home/john/vips --enable-debug
make
make install

Built-in loaders

libvips has a number of built-in loaders and savers. You can disable these if you wish, for example:

./configure --prefix=/Users/john/vips --without-nsgif --without-ppm

Dependencies

libvips has to have libglib2.0-dev and libexpat1-dev. Other dependencies are optional.

Optional dependencies

If suitable versions are found, libvips will add support for the following libraries automatically. See ./configure --help for a set of flags to control library detection. Packages are generally found with pkg-config, so make sure that is working.

Libraries like nifti do not use pkg-config so libvips will also look for them in the default path and in $prefix. If you have installed your own versions of these libraries in a different location, libvips will not see them. Use switches to libvips configure like:

./configure --prefix=/Users/john/vips \
  --with-nifti-includes=/opt/local/include \
  --with-nifti-libraries=/opt/local/lib

or perhaps:

CFLAGS="-g -Wall -I/opt/local/include -L/opt/local/lib" \
  CXXFLAGS="-g -Wall -I/opt/local/include -L/opt/local/lib" \
  ./configure --prefix=/Users/john/vips

libjpeg

The IJG JPEG library. Use the -turbo version if you can.

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.

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 PNG files using libspng. At the moment, libpng is still necessary for save.

libpng

If libspng is not present and libpng is, libvips will load PNG files with libpng. It will always save PNG files with libpng.

libimagequant

If present, libvips can write 8-bit palette-ised PNGs.

ImageMagick, or optionally GraphicsMagick

If available, libvips adds support for loading all libMagick-supported image file types. Use --with-magickpackage=GraphicsMagick to build against graphicsmagick instead.

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

Support this project with your organization. Your logo will show up here with a link to your website.

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