This program displays an image with libvips and gtk4. This is supposed to be a slightly useful image viewer. It can display huge (many, many GB) images quickly and without using much memory. It supports many scientific and technical image formats, including TIFF, WEBP, JP2K, JXL, AVIF, HEIC, PNG, JPEG, SVS, MRXS, OpenEXR, GIF, PDF, SVG, FITS, Matlab, NIfTI, Analyze, etc. It supports pixel types from 1 bit mono to 128-bit double precision complex.
All of the UI can make finding the details of image display in the sourcecode difficult. See vipsdisp-tiny for a minimal example --- that's a libvips image viewer in about 300 lines of very commented C.
It all works, though see the TODO list below.
This program is on flathub, see:
https://flathub.org/apps/org.libvips.vipsdisp
Just click "install", or enter:
flatpak install flathub org.libvips.vipsdisp
It supports many scientific and technical image formats, including TIFF, WEBP, JP2K, JXL, HEIC, AVIF, PNG, JPEG, SVS, MRXS, OpenEXR, GIF, PDF, SVG, FITS, Matlab, NIfTI, Analyze, etc. It supports many numeric pixel types, any number of image bands, many colour spaces.
It doesn't need to keep the whole image in memory. It will only read parts that it needs for display, and it understands most pyramidal image formats. This means you can open and view huge images quickly.
It has threaded, asynchronous display repaint, so pixels are computed in the background by a pool of workers. The interface stays live even under very heavy load.
It keeps a sparse pyramid of computed tiles as textures on the GPU. Each frame, it computes the set of visible tiles, and then the GPU scales, positions and composites just those tiles to the screen. CPU load should be low (except for the background workers heh). Hold down i (for "in") or + to do a smooth zoom on the cursor. If you press "d" it toggles a debug display mode which shows the tiles being computed.
Select Display control bar from the top-right menu and a useful set of visualization options appear. It supports four main display modes: Toilet roll (sorry), Multipage, Animated, and Pages as Bands.
In Toilet roll mode, a multi-page image is presented as a tall, thin strip
of images. In Multipage, you see a single page at a time, with a page-select
spinner (you can also use the crtl-<
and ctrl->
keys to flip pages). In
animated mode, pages flip automatically on a timeout. In pages-as-bands
mode, many-page single-band images (eg. OME-TIFF) are presented as a
single colour image.
You can select falsecolour and log-scale filters, useful for many scientific images. Scale and offset sliders let you adjust image brightness to see into darker areas (useful for HDR and many scientific images).
Select Save as to write an image. It can write most common formats, and lets you set file save options. It can write things like DeepZoom pyramids, PFM, OpenEXR, and so on.
Select Properties (alt-Enter) to see image metadata. It can display large amounts of metadata (useful for eg. DICOM) with filtering.
Use alt-Left and alt-Right to move between the set of images being displayed, handy for browsing a directory of images. If you drag or load a set of images, it'll flip between the images in the set. If you drag or load a single image, it'll flip between all the images in that directory.
It keeps the most recent three views live, so you can flip between them very quickly, and all view settings are preserved. This is handy for comparing details on two images.
Duplicate window
crtl-D makes a copy of the window, so you can compare two
images side by side.
It supports copy/paste and drag/drop of filenames, sets of filenames, and textures. You can paste from the screenshot tool, or drag-drop images from your file browser, for example.
It uses the gtk4 GUI toolkit, so the interface is fast, attractive and nicely animated. The image is rendered with the GPU, so display ought to be quick.
Additionally, you can drag and drop filenames, lists of filenames and textures.
cd vipsdisp
meson setup build --prefix=~/vips
cd build
ninja
ninja install
And to run:
export GSETTINGS_SCHEMA_DIR=/home/john/vips/share/glib-2.0/schemas
vipsdisp ~/pics/k2.jpg
Version needs updating in the following places:
CHANGELOG.md
meson.build
org.libvips.vipsdisp.metainfo.xml
and some release notes and a date as
well. Be exttremely careful with date formatting, and include leading zeros
on the day and month.
org.libvips.vipsdisp.json
needs the version number as a git tag.
Add the flathub
repo:
flatpak remote-add --if-not-exists \
flathub https://flathub.org/repo/flathub.flatpakrepo
Install the gtk4 SDK and runtime:
flatpak install org.gnome.Sdk//45
flatpak install org.gnome.Platform//45
Allow file. Recent security changes to git will cause submodule checkout
to fail inside flatpak. If you get errors like fatal: transport 'file' not allowed
, re-enable file transport with:
git config --global protocol.file.allow always
Build and try running it:
flatpak-builder --force-clean --user --install build-dir org.libvips.vipsdisp.json
flatpak run org.libvips.vipsdisp ~/pics/k2.jpg
Force a complete redownload and rebuild (should only rarely be necessary) with:
rm -rf .flatpak-builder
Check the files that are in the flatpak you built with:
ls build-dir/files
Uninstall with:
flatpak uninstall vipsdisp
niftiio is annoying to build, skip it.
x265 is annoying to build, skip it
we skip imagemagick as well, too huge
Install the appdata checker:
flatpak install flathub org.freedesktop.appstream-glib
flatpak run org.freedesktop.appstream-glib validate org.libvips.vipsdisp.metainfo.xml
Also:
desktop-file-validate org.libvips.vipsdisp.desktop
Make a PR on:
https://github.com/flathub/org.libvips.vipsdisp
then check the build status here:
https://flathub.org/builds/#/apps/org.libvips.vipsdisp
On success, merge to master.
skip unknown files on next / prev?
need to add the test to next-image, not glob, since we can't test the whole dir on startup
need to use next-image to pick the start image (not always the first)
need to not do this if only one file specified, eg. vipsdisp x.txt
PDF page change does not change image size if pages vary in size
^C during a slow load leaves a file in /tmp, can we improve this?
batch save?
pass revalidate down to new_from_file
on F5
have a look at the new 4.14 gtk_print_dialog_new()
works and is in branch add-print-dialog, but it needs 4.14, and the new print API is still unstable
allow eg. "vipsdisp x.svg[scale=10]", the load dialog should have a "load options" expander
can we move new_from_file
into a bg thread? the GUI will pause on huge
SVGs on zoom change right now
very difficult with the current structure -- we'd need to separate tilesource and tilecache completely, and perhaps link them with signals
tile read errors:
$ ./src/vipsdisp ~/pics/ome/LuCa-7color_Scan1.ome.tiff
- (vipsdisp:110067): VIPS-WARNING **: 18:05:16.244:
error in tile 0 x 256: tiff2vips:
out of order read -- at line 3328, but line 256 requested
page 0, subifd 2 and subifd 3 are untiled!!!
we need to decompress the whole layer before we view :(
need to separate page and zoom for ome-tiff, since we have many-page subifd pyramids
pages as bands
$ ./src/vipsdisp ~/pics/ome/LuCa-7color_Scan1.ome.tiff
flip to last page, zoom, lots of repaint errors
maybe join first N pages (while pages same size) in pages as bands
mode?
does not page flip to smaller pages correctly
reset zoom/scroll on pageflip if the page size changes?
same for audi r8 pdf page flip I guess?
info bar:
pages as bands ... info bar displays only one band
will not display complex numbers correctly ... need to unpack to bands, or does getpoint do this already?
zooming:
better pinch zoom support
we should take the coordinates of the pinch gesture into account
can test this now I have a multitouch trackpad
we could shrink tiles on zoom out (we only expand tiles now)
before we can do fancy PDF zooming, we'll need to split page and zoom in tile_source_open()
how should we handle images which include labels, macros, thumbnails?
load options? save options?
display images in properties? perhaps a thumbnail? set attach-associated?
appear as eg.:
openslide.associated.thumbnail 1024x732 uchar, 4 bands, srgb