Preview feature for finder.



Can be opened in full screen and launched from the command line,  multi-page documents like PowerPoint slide shows can be navigate



⌘ Cmd-Y
space
⌥ Opt-space (open in full screen)
⌥ Opt hold to zoom an image to actual size (Quick Look must already be open)



qlmanage -- Quick Look Server debug and management tool

     qlmanage -r

     qlmanage -m [name ...]

     qlmanage -t [-d debugLevel] [-x] [-i] [-s size] [-f factor] [-c contentTypeUTI [-g generator]] [file ...]

     qlmanage -p [-d debugLevel] [-x] [-c contentTypeUTI [-g generator]] [file ...]

     qlmanage -h


     qlmanage allows you to test your Quick Look generators and manage Quick Look Server.


-r resets Quick Look Server and all Quick Look client's generator cache.

-m information server including the list of detected generators.

> qlmanage -m  |head -3
erver: living for 2875s (31 requests handled) - instant off: yes - arch: X86_64 - user id: 501
memory used: 0 MB (875664 bytes) - used descriptors: 24/256
last burst: during 0.002s - 3 requests - 0.001s idle

# use preview to  krop images, then write back to file

> qlmanage -m  |head -3
server: living for 2912s (32 requests handled) - instant off: yes - arch: X86_64 - user id: 501
memory used: 0 MB (934640 bytes) - used descriptors: 24/256
last burst: during 0.068s - 1 requests - 0.000s idle

server: living for 2476s (31 requests handled) - instant off: yes - arch: X86_64 - user id: 501
memory used: 0 MB (875008 bytes) - used descriptors: 24/256
last burst: during 0.002s - 3 requests - 0.001s idle
plugins:
  org.openxmlformats.presentationml.slideshow -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.adobe.pdf -> /System/Library/QuickLook/PDF.qlgenerator (696.7)
  com.apple.localized-pdf-bundle -> /System/Library/QuickLook/LocPDF.qlgenerator (696.7)
  public.3d-content -> /System/Library/QuickLook/SceneKit.qlgenerator (332.8)
  com.apple.iwork.keynote.key -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.ical.bookmark -> /System/Library/QuickLook/iCal.qlgenerator (696.7)
  com.apple.application -> /System/Library/QuickLook/StandardBundles.qlgenerator (696.7)
  com.microsoft.word.doc -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.microsoft.powerpoint.pot -> /System/Library/QuickLook/Office.qlgenerator (32)
  org.openxmlformats.wordprocessingml.template.macroenabled -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.iwork.keynote.sffkey -> /Library/QuickLook/iWork.qlgenerator (146)
  dyn.ah62d4qmuhk2x43dts71g255bqu -> /System/Library/QuickLook/Package.qlgenerator (696.7 - loaded)
  com.apple.ichat.ichat -> /System/Library/QuickLook/iChat.qlgenerator (5100)
  com.apple.notes.externalrecord -> /System/Library/QuickLook/Notes.qlgenerator (555.10.42)
  com.microsoft.word.dot -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.iwork.keynote.sffkth -> /Library/QuickLook/iWork.qlgenerator (146)
  org.openxmlformats.presentationml.template.macroenabled -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.keynote.key -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.mail.email -> /System/Library/QuickLook/Mail.qlgenerator (3124)
  com.apple.iwork.pages.sfftemplate -> /Library/QuickLook/iWork.qlgenerator (146)
  public.movie -> /System/Library/QuickLook/Movie.qlgenerator (696.7)
  com.apple.iwork.keynote.kth -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.iwork.numbers.sffnumbers -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.package -> /System/Library/QuickLook/Package.qlgenerator (696.7 - loaded)
  org.openxmlformats.wordprocessingml.document.macroenabled -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.iwork.pages.sffpages -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.ical.ics -> /System/Library/QuickLook/iCal.qlgenerator (696.7)
  org.oasis-open.opendocument.text -> /System/Library/QuickLook/Text.qlgenerator (696.7)
  org.openxmlformats.wordprocessingml.template -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.ical.ics.event -> /System/Library/QuickLook/iCal.qlgenerator (696.7)
  com.microsoft.excel.xlt -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.iwork.numbers.sfftemplate -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.iwork.keynote.key-tef -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.ibooksauthor.book -> /Library/QuickLook/iBooksAuthor.qlgenerator (1.0)
  com.apple.internet-location -> /System/Library/QuickLook/Clippings.qlgenerator (696.7)
  com.rsa.pkcs-12 -> /System/Library/QuickLook/Security.qlgenerator (55065.40.1)
  org.openxmlformats.presentationml.slideshow.macroenabled -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.microsoft.word.stationery -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.ibooks-folder -> /System/Library/QuickLook/iBooks.qlgenerator (1)
  public.x509-printable-encoded-archive -> /System/Library/QuickLook/Security.qlgenerator (55065.40.1)
  public.xml -> /System/Library/QuickLook/Text.qlgenerator (696.7)
  org.openxmlformats.wordprocessingml.document -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.rtfd -> /System/Library/QuickLook/Text.qlgenerator (696.7)
  com.apple.systempreference.prefpane -> /System/Library/QuickLook/StandardBundles.qlgenerator (696.7)
  org.openxmlformats.spreadsheetml.template -> /System/Library/QuickLook/Office.qlgenerator (32)
  org.vim.sql-file -> /System/Library/QuickLook/Text.qlgenerator (696.7)
  com.apple.keychain -> /System/Library/QuickLook/Security.qlgenerator (55065.40.1)
  public.font -> /System/Library/QuickLook/Font.qlgenerator (696.7)
  public.x509-certificate -> /System/Library/QuickLook/Security.qlgenerator (55065.40.1)
  com.apple.iwork.pages.template -> /Library/QuickLook/iWork.qlgenerator (146)
  com.adobe.illustrator.ai-image -> /System/Library/QuickLook/EPS.qlgenerator (696.7)
  public.vcard -> /System/Library/QuickLook/Contact.qlgenerator (696.7)
  com.apple.finder.textclipping -> /System/Library/QuickLook/Clippings.qlgenerator (696.7)
  org.openxmlformats.presentationml.template -> /System/Library/QuickLook/Office.qlgenerator (32)
  org.openxmlformats.spreadsheetml.template.macroenabled -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.iwork.numbers.numbers -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.iwork.pages.pages -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.ichat.transcript -> /System/Library/QuickLook/iChat.qlgenerator (5100)
  com.apple.mail.emlx -> /System/Library/QuickLook/Mail.qlgenerator (3124)
  com.apple.iconset -> /System/Library/QuickLook/Icon.qlgenerator (696.7)
  com.apple.addressbook.group -> /System/Library/QuickLook/Contact.qlgenerator (696.7)
  com.apple.property-list -> /System/Library/QuickLook/Text.qlgenerator (696.7)
  org.idpf.epub-container -> /System/Library/QuickLook/iBooks.qlgenerator (1)
  com.apple.addressbook.person -> /System/Library/QuickLook/Contact.qlgenerator (696.7)
  com.apple.safari.history -> /System/Library/QuickLook/Bookmark.qlgenerator (696.7)
  public.html -> /System/Library/QuickLook/Web.qlgenerator (696.7)
  com.apple.iwork.numbers.template -> /Library/QuickLook/iWork.qlgenerator (146)
  com.microsoft.powerpoint.pps -> /System/Library/QuickLook/Office.qlgenerator (32)
  public.plain-text -> /System/Library/QuickLook/Text.qlgenerator (696.7)
  com.apple.safari.bookmark -> /System/Library/QuickLook/Bookmark.qlgenerator (696.7)
  public.audio -> /System/Library/QuickLook/Audio.qlgenerator (696.7)
  org.idpf.epub-folder -> /System/Library/QuickLook/iBooks.qlgenerator (1)
  com.apple.pict -> /System/Library/QuickLook/Clippings.qlgenerator (696.7)
  public.xhtml -> /System/Library/QuickLook/Web.qlgenerator (696.7)
  org.openxmlformats.presentationml.presentation.macroenabled -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.finder.pictclipping -> /System/Library/QuickLook/Clippings.qlgenerator (696.7)
  com.apple.ical.bookmark.todo -> /System/Library/QuickLook/iCal.qlgenerator (696.7)
  com.apple.iwork.numbers.numbers-tef -> /Library/QuickLook/iWork.qlgenerator (146)
  com.apple.webarchive -> /System/Library/QuickLook/Web.qlgenerator (696.7)
  org.openxmlformats.presentationml.presentation -> /System/Library/QuickLook/Office.qlgenerator (32)
  public.svg-image -> /System/Library/QuickLook/Web.qlgenerator (696.7)
  com.apple.private.live-photo-bundle -> /System/Library/QuickLook/LivePhoto.qlgenerator (696.7)
  public.image -> /System/Library/QuickLook/Image.qlgenerator (696.7)
  org.openxmlformats.spreadsheetml.sheet -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.microsoft.excel.xls -> /System/Library/QuickLook/Office.qlgenerator (32)
  org.openxmlformats.spreadsheetml.sheet.macroenabled -> /System/Library/QuickLook/Office.qlgenerator (32)
  public.rtf -> /System/Library/QuickLook/Text.qlgenerator (696.7)
  com.apple.iwork.pages.pages-tef -> /Library/QuickLook/iWork.qlgenerator (146)
  com.microsoft.powerpoint.ppt -> /System/Library/QuickLook/Office.qlgenerator (32)
  public.comma-separated-values-text -> /System/Library/QuickLook/Office.qlgenerator (32)
  com.apple.ical.ics.todo -> /System/Library/QuickLook/iCal.qlgenerator (696.7)
  com.adobe.encapsulated-postscript -> /System/Library/QuickLook/EPS.qlgenerator (696.7)


-t displays generated thumbnails (if available) for the specified files.

-p displays generated previews for the specified files.

-h displays extensive help.


qlmanage [OPTIONS] path...
    -r      Force reloading Generators list
    -r cache    Reset thumbnail disk cache
    -m [name ...]   Display statistics about quicklookd. Stats names:
            * plugins   Show the generators list
            * server    Show quicklookd life information
            * memory    Show quicklookd memory consumption
            * burst     Show statistics about the last burst
            * threads   Show concurrent accesses stats
            * other     Show other information about quicklookd
    -d debugLevel   Integer between 1-4
    -p              Compute previews of the documents
    -t              Compute thumbnails of the documents
    -x              Use quicklookd (remote computation)
    -i              Compute thumbnail in icon mode
    -s size         Size for the thumbnail
    -f factor       Scale factor for the thumbnail
    -F factor       Scale factor for the thumbnail, draw downscaled and compare to 1x
    -z              Display generation performance info (don't display thumbnails)
    -o dir          Output result in dir (don't display thumbnails or previews)
    -c contentType  Force the content type used for the documents
    -g generator    Force the generator to use




qlmanage -p file

qlmanage -r cache  # reset cache

/var/folders/rrrrr/com.apple.QuickLook.thumbnailcache



/Library/QuickLook > du
   44   ./iBooksAuthor.qlgenerator/Contents
18908   ./iWork.qlgenerator/Contents



11:23:46  com.apple.xpc.launchd[1] (com.apple.quicklook[70826]): 
                Endpoint has been activated through legacy launch(3) APIs. Please switch to +XPC or bootstrap_check_in(): com.apple.quicklook
11:23:50  quicklookd[70826]: IconServices logging is enabled,
 x9
11:23:50  iconservicesagent[438]: -[ISGenerateImageOp generateImageWithCompletion:] 
                Failed to composit image for descriptor .
 x9
11:37:51 quicklookd[78625]: Error returned from iconservicesagent: (null)



/System/Library/LaunchAgents/.com.apple.quicklook
        .32bit
        .config
        .ui.helper