Clicking on wikimedia commons picture shows wrong picture (instead empty screen) for several seconds before displaying correct one

[mnalis]

What steps will reproduce the problem?

1. open some map area
2. click on File / Load images from wikimedia commons
3. click on one loaded image. Screen is grey until picture loads (which may take few seconds), and only then is new picture displayed - which is fine and expected
4. close the screen with images
5. click on another loaded image.

What is the expected result?

the picture screen should remain empty (grey) in step 5. until the new image is retrieved and displayed (just like it does in step 3.)

What happens instead?

the old picture is displayed immediately, and only after some time (when new picture is retrieved, which may take few seconds) is it replaced by new picture. That is extremely confusing, and unless one is very alert easily results in taking actions based on wrong picture.

Please provide any additional information below. Attach a screenshot if possible.

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2023-12-07 13:35:12 +0100 (Thu, 07 Dec 2023)
Revision:18907
Build-Date:2023-12-07 16:38:49
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (18907 en) Linux Debian GNU/Linux 12 (bookworm)
Memory Usage: 1050 MB / 3936 MB (526 MB allocated, but free)
Java version: 17.0.9+9-Debian-1deb12u1, Debian, OpenJDK 64-Bit Server VM
Look and Feel: javax.swing.plaf.metal.MetalLookAndFeel
Screen: :0.0 1920×1080 (scaling 1.00×1.00)
Maximum Screen Size: 1920×1080
Best cursor sizes: 16×16→16×16, 32×32→32×32
Environment variable LANG: C.UTF-8
System property file.encoding: UTF-8
System property sun.jnu.encoding: UTF-8
Locale info: en
Numbers with default locale: 1234567890 -> 1234567890
Desktop environment: ICEWM
VM arguments: [--patch-module=java.desktop=/usr/share/icedtea-web/javaws.jar:, --add-reads=java.base=ALL-UNNAMED,java.desktop, --add-reads=java.desktop=ALL-UNNAMED,java.naming, --add-reads=java.naming=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/sun.awt=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/javax.jnlp=ALL-UNNAMED,java.desktop, --add-exports=java.base/com.sun.net.ssl.internal.ssl=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.net.www.protocol.jar=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.security.action=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.security.provider=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.security.util=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.security.validator=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.security.x509=ALL-UNNAMED,java.desktop, --add-exports=java.base/jdk.internal.util.jar=ALL-UNNAMED,java.desktop, --add-exports=java.base/sun.net.www.protocol.http=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/sun.awt.X11=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/sun.applet=ALL-UNNAMED,java.desktop, --add-exports=java.desktop/sun.applet=ALL-UNNAMED,jdk.jsobject, --add-exports=java.naming/com.sun.jndi.toolkit.url=ALL-UNNAMED,java.desktop, -Dicedtea-web.bin.name=javaws, -Dicedtea-web.bin.location=/usr/share/icedtea-web/bin/javaws.sh, -Djava.security.manager, -Djava.security.policy=/etc/icedtea-web/javaws.policy]
Dataset consistency test: No problems found

Plugins:
+ DirectUpload (36178)
+ FixAddresses (36126)
+ ImageWayPoint (36126)
+ PicLayer (1.0.3)
+ Review.Changes (1.1.1)
+ apache-commons (36176)
+ apache-http (36176)
+ areaselector (2.6.2)
+ austriaaddresshelper (88)
+ buildings_tools (36178)
+ conflation (0.6.11)
+ ejml (36176)
+ imagery_offset_db (36126)
+ jna (36176)
+ jts (36004)
+ log4j (36176)
+ osmwiki-dataitem (0.0.8)
+ pt_assistant (632)
+ reverter (36126)
+ turnrestrictions (36178)
+ undelete (36126)
+ utilsplugin2 (36178)
+ wikipedia (605)

Tagging presets:
+ https://<user.name>.com/prezentacije/OpenStreetMap/josm-preset.xml
+ https://raw.githubusercontent.com/OpenNauticalChart/josm/master/INT-1-preset.xml
+ https://josm.openstreetmap.de/josmfile?page=Presets/Healthcare&zip=1

Map paint styles:
- https://josm.openstreetmap.de/josmfile?page=Styles/PublicTransport&zip=1
+ http://bezdomni.net/Styles_HighlightedCapesBays-style.mapcss
+ https://josm.openstreetmap.de/josmfile?page=Styles/ColorWays&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Coloured_Streets&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Fixme&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Modified&zip=1

Validator rules:
+ https://josm.openstreetmap.de/josmfile?page=Rules/KeepRight&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/QAToolInspiredValidations&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/OSMLint&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/MissingWeekdays&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/SourceObjectTag&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/IndoorRules&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/Pictures&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/MissingOpeningHours&zip=1
+ https://josm.openstreetmap.de/josmfile?page=Rules/CheckDate&zip=1

Last errors/warnings:
- 00370.342 W: java.net.SocketTimeoutException: Connect timed out
- 00370.342 W: java.net.SocketTimeoutException: Connect timed out
- 07325.122 W: Unable to load https://upload.wikimedia.org/wikipedia/commons/f/f9/Chloromyia_formosa_?_(ID_to_be_confirmed),_Maksimir_Park,_Zagreb,_Croatia_(48189047451).jpg

[mnalis]

after clicking on new image at 00:13, wrong picture is displayed for few moments (on slower connections, that takes even longer)

[taylor.smock]

In 18924/josm:

Fix #23359: Don't keep images in memory when the ImageViewerDialog is closed

[skyper]

#23362 looks like a regression.

[GerdP]

#23415 looks like a regression

[GerdP]

Maybe the simple patch for #22819 is the better solution? It also helps when the dialog is not closed before another image is selected.

[GerdP]

I think this change should be reverted now, I believe r18945 is the better solution as it doesn't force a reload when you just press 'y' to hide the dialog and 'y' to show it again (that's my typical work flow with images: Look at the image, hide it with 'y' and change some OSM data, then press 'y' again to check if the changed data matches the image.)

[taylor.smock]

I'm open to that.

[taylor.smock]

Something changed recently which forces a clear between showing the images; this is non-ideal when going through images quickly. As an example: if I drive from Colorado to Maine and take an image every second, I'm going to go through some image sections rather quickly (think interstate -- I typically don't care until I see a speed limit sign).

Think epilepsy (I don't have that, but the bright flash between images does give me a headache after awhile).

[GerdP]

In 18946/josm:

see #23359: revert changes from r18924 as they are now obsolete

[GerdP]

Ah, sorry, didn't see comment:9 before my commit. You probably refer to the change in r18945 ?
Do you see a good way to reduce the flicker? I can only think of some kind of timer which would allow to show the old image for a fraction of a second and then either show the new one or a text that shows that the new image is still loading or couldn't be loaded.

[taylor.smock]

No worries. I suspect r18945, but I'm not 100% on that -- I'll have to back it out (locally; not via a commit) and check.
Rather unfortunately for me, I'm currently profiling some actions on large datasets. So it might be awhile before I get around to checking that.