I don't know what you need for your urls with image linksproblem, but Preview that comes on a Mac does Batch resizing. To do batch operations just drag the image files or a complete folder to the dock and drop on Preview and it will open with all the images open in the sidebar. Select them all (command A) or just the files you want using command. Next go to Previews Tools menu and select Adjust Size and a dialog box will open to let you adjust to the size you need.
Preview does most of what IrfanView does and things IrfanView doesn't do.
Some IrfanView features:
▪ Many supported file formats
▪ Multi language support Preview does
▪ Thumbnail/preview option Preview does
▪ Paint option - to draw lines, circles, arrows, straighten image etc. Preview Annotates with arrows, boxes, circles and text
▪ Toolbar skins option No
▪ Slideshow (save slideshow as EXE/SCR or burn it to CD) Preview does slide shows, but to save or burn use iPhoto or iMovie
▪ Show EXIF/IPTC/Comment text in Slideshow, Preview No, iPhoto yes
▪ Support for Adobe Photoshop Filters No
▪ Fast directory view (moving through directory) Preview does
▪ Batch conversion (with image processing) Preview does somethings like resize or rotate
▪ Multipage TIF editing Don't know
▪ File search Preview does
▪ Email option Preview does
▪ Multimedia player Preview No, Quicklook yes
▪ Print option Preview does
▪ Support for embedded color profiles in JPG/TIF Preview does
▪ Change color depth Don't kmow
▪ Scan (batch scan) support Preview does
▪ Cut/crop Preview does
▪ IPTC editing Preview does
▪ Effects (Sharpen, Blur, Adobe 8BF, Filter Factory, Filters Unlimited, etc.) Preview does Sharpen and Color Correction but no Adobe filters
▪ Screen Capturing Preview does
▪ Extract icons from EXE/DLL/ICLs No EXE, DLL's or ICL's on a Mac
▪ Lossless JPG rotation Preview does
▪ Unicode support Preview ?
▪ Many hotkeys Preview does
▪ Many command line options No
▪ Many PlugIns No
▪ Only one EXE-type file, no DLLs, no Shareware messages like "I Agree" or "Evaluation expired" Preview is only one file, there are no DLLs on a Mac and of course no Nag screens in Preview
▪ No registry changes without user action/permission! No registry on a Mac
▪ and much much more Preview does PDF's as well as images