Quick Look
Quick Look enables apps like Finder and Mail to display thumbnail images and full-size previews of Keynote, Numbers, Pages, and PDF documents, as well as images and other types of files. These previews can be tremendously helpful when a user is trying to locate a specific document.
Quick Look is a quick preview feature developed by Apple Inc. Which was introduced in its operating system Mac OS X 10.5 Leopard. The feature was announced at the Worldwide Developers Conference on Jun. While macOS's Finder has always had icon previews, Quick Look allows users to look at the contents of a file in the Finder at full or near-full size, depending on the size of the. The Quick Look command in OS X displays the contents of the selected file in a floating window. The key point is that you can see what's in a file without double-clicking (to open) it and without launching any application. This is quite handy when you want to peek at the contents of a file. I love Leopard's Quick Look feature. Is there any way that we can do a Quick Look at a file, without opening it, and print it from the Finder? Sort of, but there's a bump along the way. OS X's Quick Look lets you view a file's contents by selecting it in the Finder and then pressing the spacebar. There's no need to wait for the file to open in an application—it appears.
Implement a Quick Look viewer in your app if it makes sense. If your app lets people attach or otherwise interact with files—especially files your app doesn't natively support—consider implementing a Quick Look viewer so people can preview those files without leaving your app.
Consider implementing a Quick Look generator if your app produces custom file types. A Quick Look generator enables other apps, including Finder and Spotlight, to display previews of your documents, making it easier for people to find your content.
For developer guidance, see Quick Look Programming Guide and Quick Look.
| Developer(s) | Apple Inc. |
|---|---|
| Initial release | October 26, 2007 (Mac OS X 10.5 'Leopard') |
| Operating system | macOS |
| License | Proprietary |
| Website | Quick Look |
Quick Look is a quick preview feature developed by Apple Inc. which was introduced in its operating systemMac OS X 10.5 Leopard. The feature was announced at the Worldwide Developers Conference on Jun. 11, 2007.
While macOS's Finder has always had icon previews, Quick Look allows users to look at the contents of a file in the Finder at full or near-full size, depending on the size of the document relative to the screen resolution. It can preview files such as PDFs, HTML, QuickTime readable media, plain text and RTF text documents, iWork (Keynote, Pages, and Numbers) documents, ODF documents, Microsoft Office (Word, Excel, and PowerPoint) files (including OOXML), and RAW camera images.[citation needed]
Quick Look can also be opened in full screen and launched from the command line. Additionally, multi-page documents like PowerPoint slide shows can be navigated using the slide previews at the side of the preview window.
Quick Look technology is implemented throughout the Apple suite of software starting with Mac OS X 10.5, including iChat Theater, Time Machine, and Finder's Cover Flow.
Quick Look APIs are available to developers via the Quick Look framework on iOS[1] and as part of the Quartz framework on the Mac.[2]
Supported file types by default[edit]
Since its debut, Quick Look has included a number of generators for common file types.
| Format | Version introduced | Notes |
|---|---|---|
| AAC | 10.5 | Cover art in icon view and can play back audio in full preview. |
| Adobe Photoshop | 10.5 | |
| AIFF | 10.5 | |
| Apple Icon Image format | 10.5 | |
| AVI | 10.5 | |
| BMP | 10.5 | |
| COLLADA's DAE | 10.6 | |
| Cinema 4D's .c4d | Displays the 2D Preview Image embedded in the file. | |
| GIF | 10.5 | Did not animate animated GIFS[3] without additional plugins[4] until OS X 10.7.[5] |
| HTML | 10.5 | Does not load remote resources or execute scripts. |
| iChat transcripts | 10.5 | |
| JPEG | 10.5 | |
| JPEG 2000 | 10.5 | |
| Microsoft Excel | 10.5 | |
| Microsoft PowerPoint | 10.5 | |
| Microsoft Word | 10.5 | |
| MIDI | 10.5 | MIDI files support has been dropped in OS X 10.8. |
| MP3 | 10.5 | Cover art in icon view and can play back audio in full preview. |
| MPEG4 | 10.5 | |
| MPO | ||
| 10.5 | ||
| PictureClipping | 10.6 | |
| PICT | 10.5 | |
| PNG | 10.5 | |
| QuickTime movies | 10.5 | Additional stream formats require the appropriate QuickTime extension to be installed. |
| RTF | 10.5 | |
| SVG | 10.6 | |
| TEXT | 10.5 | |
| TextClipping | 10.6 | |
| TIFF | 10.5 | |
| WAV | 10.5 |
Plug-ins[edit]
Plug-ins can be added to Quick Look to allow previewing the content of other file formats. Plug-ins can also be used to add additional functionality to Quick Look such as syntax highlighting for source code files.[6]
To add a plug-in to Quick Look it needs to be placed in the folder /Library/QuickLook/. To activate that plug-in, either the computer needs to be restarted or Quick Look needs to be reset with the command
Usage[edit]
There are multiple ways to invoke Quick Look.
Keyboard shortcuts:
- ⌘ Cmd-Y
- space
- ⌥ Opt-space (open in full screen)
- ⌥ Opt hold to zoom an image to actual size (Quick Look must already be open)
Command line:[7]
Menu:
- File — Quick Look file name;
- Context menu (right-click or Control-mouse click), then Quick Look file name.
Caching and Forensics[edit]
Quick Look can be exploited when conducting a forensic examination of a computer's contents. A thumbnail cache is created for each user in a random subfolder of /var/folders called com.apple.QuickLook.thumbnailcache. The cache contains two files;
Since its debut, Quick Look has included a number of generators for common file types.
| Format | Version introduced | Notes |
|---|---|---|
| AAC | 10.5 | Cover art in icon view and can play back audio in full preview. |
| Adobe Photoshop | 10.5 | |
| AIFF | 10.5 | |
| Apple Icon Image format | 10.5 | |
| AVI | 10.5 | |
| BMP | 10.5 | |
| COLLADA's DAE | 10.6 | |
| Cinema 4D's .c4d | Displays the 2D Preview Image embedded in the file. | |
| GIF | 10.5 | Did not animate animated GIFS[3] without additional plugins[4] until OS X 10.7.[5] |
| HTML | 10.5 | Does not load remote resources or execute scripts. |
| iChat transcripts | 10.5 | |
| JPEG | 10.5 | |
| JPEG 2000 | 10.5 | |
| Microsoft Excel | 10.5 | |
| Microsoft PowerPoint | 10.5 | |
| Microsoft Word | 10.5 | |
| MIDI | 10.5 | MIDI files support has been dropped in OS X 10.8. |
| MP3 | 10.5 | Cover art in icon view and can play back audio in full preview. |
| MPEG4 | 10.5 | |
| MPO | ||
| 10.5 | ||
| PictureClipping | 10.6 | |
| PICT | 10.5 | |
| PNG | 10.5 | |
| QuickTime movies | 10.5 | Additional stream formats require the appropriate QuickTime extension to be installed. |
| RTF | 10.5 | |
| SVG | 10.6 | |
| TEXT | 10.5 | |
| TextClipping | 10.6 | |
| TIFF | 10.5 | |
| WAV | 10.5 |
Plug-ins[edit]
Plug-ins can be added to Quick Look to allow previewing the content of other file formats. Plug-ins can also be used to add additional functionality to Quick Look such as syntax highlighting for source code files.[6]
To add a plug-in to Quick Look it needs to be placed in the folder /Library/QuickLook/. To activate that plug-in, either the computer needs to be restarted or Quick Look needs to be reset with the command
Usage[edit]
There are multiple ways to invoke Quick Look.
Keyboard shortcuts:
- ⌘ Cmd-Y
- space
- ⌥ Opt-space (open in full screen)
- ⌥ Opt hold to zoom an image to actual size (Quick Look must already be open)
Command line:[7]
Menu:
- File — Quick Look file name;
- Context menu (right-click or Control-mouse click), then Quick Look file name.
Caching and Forensics[edit]
Quick Look can be exploited when conducting a forensic examination of a computer's contents. A thumbnail cache is created for each user in a random subfolder of /var/folders called com.apple.QuickLook.thumbnailcache. The cache contains two files;
- index.sqlite which is a SQLite database containing two tables - files and thumbnails.
- files contains the name, path, file-identifier, and volume-identifier of each file in the database.
- thumbnails contains metadata about each thumbnail, including the file linked-to in the files table and the offset of its data contained in thumbnails.data.
Quick Look Mac Os
- thumbnails.data contains the raw bitmaps of the cached thumbnails.
Quick Look thumbnails are stored for documents on internal disks and also for documents located on removable disks, including those that have been encrypted and can pose a significant security hole. A document may well have a number of thumbnails, each having different dimensions that can range from very large to very small.
The cache can be reset by invoking the qlmanage -r cache command via a Terminal window.
See also[edit]
References[edit]
- ^https://developer.apple.com/library/ios/documentation/FileManagement/Conceptual/DocumentInteraction_TopicsForIOS/Articles/UsingtheQuickLookFramework.html
- ^https://developer.apple.com/library/mac/documentation/userExperience/Conceptual/Quicklook_Programming_Guide/Introduction/Introduction.html
- ^http://www.mac-forums.com/forums/os-x-apps-games/51197-animated-gif-plugin-preview.html
- ^http://sourceforge.net/projects/animgifqlgen/
- ^http://forums.macrumors.com/showthread.php?t=475195
- ^Frakes, Dan (January 22, 2008). 'More Quick Look plug-ins'. Macworld. Retrieved September 15, 2014.
- ^https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man1/qlmanage.1.html
External links[edit]
- Gloobus, a Linux application based on Quick Look
Quick Look Mac Os X
