I think I have a credible list of remaining image file candidates that are corrupt in some way or unviewable. I used find/xargs and imagemagick 'identify' to find the files. I looked for XCF/JPG/JPEG/GIF/SVG/SVGZ/PNG files. (Did I miss any formats?)
Considering the thousands of image files, this is a very short list! :-)
I already fixed several images using upstream sources.
The first remedy was to find the original sources from upstream and hope the image files there were not corrupt. I have exhausted that search. I'll leave to the image experts regarding the best way to repair, if at all.
Darrell
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SVG/SVGZ:
identify: no decode delegate for this image format `./tdegraphics/ksvg/test/tiger.svg' @ error/svg.c/ReadSVGImage/2815.
applications/tdesvn/src/pics/hisc-action-tdesvnaddrecursive.svgz ('identify -verbose' stalls with this image; opens in gwenview without incident; opens in karbon but incompletely; definitely something awry)
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PNG:
(These images are no longer found upstream. Several days ago I emailed the developer --- no response yet.)
identify: improper image header `./libraries/pytdeextensions/app_templates/kcontrol_module/src/hi16-app-kcontrol_module.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./libraries/pytdeextensions/app_templates/kcontrol_module/src/hi32-app-kcontrol_module.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./libraries/pytdeextensions/app_templates/kdeapp/src/hi16-app-kdeapp.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./libraries/pytdeextensions/app_templates/kdeapp/src/hi32-app-kdeapp.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./libraries/pytdeextensions/app_templates/kdeutility/src/hi16-app-kdeutility.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./libraries/pytdeextensions/app_templates/kdeutility/src/hi32-app-kdeutility.png' @ error/png.c/ReadPNGImage/2957.
(This image from KDE 3.5.10 to 3.4.1 is corrupt too. The default English version: tdeedu/doc/kvoctrain.)
identify: Ignoring bad adaptive filter type `./tde-i18n/tde-i18n-de/docs/tdeedu/kvoctrain/verb-query-dlg.png' @ warning/png.c/PNGWarningHandler/1472.
identify: Extra compressed data `./tde-i18n/tde-i18n-de/docs/tdeedu/kvoctrain/verb-query-dlg.png' @ warning/png.c/PNGWarningHandler/1472.
identify: Extra compression data `./tde-i18n/tde-i18n-de/docs/tdeedu/kvoctrain/verb-query-dlg.png' @ warning/png.c/PNGWarningHandler/1472.
identify: IDAT: CRC error `./tde-i18n/tde-i18n-de/docs/tdeedu/kvoctrain/verb-query-dlg.png' @ error/png.c/PNGErrorHandler/1455.
identify: corrupt image `./tde-i18n/tde-i18n-de/docs/tdeedu/kvoctrain/verb-query-dlg.png' @ error/png.c/ReadPNGImage/2995.
(These images from KDE 3.5.10 to 3.1.5 are corrupt too.)
identify: improper image header `./tdesdk/kapptemplate/kapp/hi16-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kapp/hi32-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kapp/hi48-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kapp/lo16-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kapp/lo32-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kpartapp/hi16-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kpartapp/hi32-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kpartapp/hi48-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kpartapp/lo16-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kpartapp/lo32-app-app.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kpartplugin/hi16-action-plugin.png' @ error/png.c/ReadPNGImage/2957.
identify: improper image header `./tdesdk/kapptemplate/kpartplugin/hi22-action-plugin.png' @ error/png.c/ReadPNGImage/2957.
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