“VirtualDub”的意思、由来-开放百科全书

In 2009, the third-party software print guide Learning VirtualDub referred to VirtualDub as "the leading free Open Source video capture and processing tool".^[4] Due to its "powerful"^[5] versatility and usefulness especially in the field of video processing (see below), PC World has referred to VirtualDub as "something of a 'Photoshop' for video files",^[6] PC Perspective recommends it for its low overhead,^[7] and nextmedia's PC & Tech Authority particularly praises it for its Direct stream copy feature to avoid generational degradation of video quality when performing simple editing and trimming tasks and the fact that VirtualDub "offers several valuable features that other packages lack, and helps you get quick results without any fuss or patronising wizards".^[8]

VirtualDub is recommended for use by professional computer and tech magazines, guides, and reviewers such as PC World,^[5] PC & Tech Authority,^[6] PC Perspective,^[7] technologies guide website MakeTechEasier,^[8] freeware and open source software review site Ghacks,^[9] Speed Demos Archive,^[10] as well as third-party professional video production companies,^[11] video-game developer Valve Corporation,^[12] and the creators of Wine (software).^[13] Several hundred third-party plug-ins for VirtualDub exist,^[14]^[15]^[16]^[17]^[18]^[19] including by professional software companies.^[20]^[21] Furthermore, Debugmode Wax allows use of VirtualDub plug-ins in professional video editing software such as Adobe Premiere Pro and Vegas Pro.^[22]

Features

VirtualDub is designed for Microsoft Windows but may run on Linux and Mac OS X using Wine. (For example, to use it with the popular Deshaker plugin.^[23]) However, native support for these systems is not available.

VirtualDub was made to operate exclusively on AVI files; however, a plugin API was added from version 1.7.2 which allows the import of other formats.^[24] Appropriate video and audio codecs need to be installed.

Video capture

VirtualDub supports both DirectShow and Video for Windows for video capture. Capture features include capture to any AVI variant, audio VU meters, overlay and preview modes, histogram, selectable crop area, video noise reduction, auto stop settings (based on capture time, file size, free space, and/or dropped frames), and designate alternate drive(s) for capture overflow. VirtualDub can help overcome problems with digital cameras that also record video. Many models,{{weasel inline|date=September 2014}} especially Canon,{{which|date=September 2014}} record in an M-JPEG format incompatible with Sony Vegas 6.0 and 7.0. Saving AVI files as "old-style AVI" files allows them to appear in Vegas.

VirtualDub supports DV capture from Type 2 (VfW) FireWire controllers only. (It cannot work with Type 1). There is no DV batch capture, still image capture, or DV device control capability.

Video assembly

VirtualDub can create a video file from a series image files in Truevision TGA or Windows Bitmap file formats. Individual frames must be given file names numbered in sequential order without any gaps (e.g. 001.bmp, 002.bmp, 003.bmp...). From those, the frame rate can be adjusted, and other modifications such as the addition of a sound track can be made.

VirtualDub can also disassemble a video by extracting its sound tracks saving its frames into Truevision TGA or Windows Bitmap files.

Editing

VirtualDub can delete segments of a video file, append new segments, or reorder existing segments. Appended segments must have similar audio and video formats, dimensions, number of audio channels, frame rates and sampling rates. Otherwise, VirtualDub is incapable of mixing dissimilar video files or adding transition effects between segments.

Video processing

VirtualDub comes with a number of video editing components known as "filters". They can perform basic tasks as arbitrary resize, converting the video to grayscale, arbitrary rotation, crop, or changing simple values like brightness and contrast. Filters may be used during the video assembly as well. Filter plug-ins further extend VirtualDub's capabilities. A plug-in SDK is available for developers to create their own video and audio filters.^[25]

Besides those basic features, its many third-party plug-ins make VirtualDub a "powerful"^[10] open-source tool when it comes to linear video processing, and in fact most of the hundreds of third-party plug-ins available for VirtualDub are filters related to either aesthetic effects or cleaning, fixing, and restoring image quality, such as various denoising and sharpening methods targeted especially at analogue and digital video signal and film defects (be they related to VHS, faulty cables, a distorted analogue terrestrial or satellite TV reception, or digital compression), deinterlacing and fields manipulation, colorspace conversion and manipulation, reverse telecine aka IVTC, deflickering, deshaking, adding and removing logos and subtitles, analysis of video content, etc.

All of these processing features are fully batchable to apply the same effects on a large number of files.

Development

VirtualDub was originally created for the purpose of compressing anime videos of Sailor Moon.^[26]

VirtualDub is free software, released under the GNU General Public License and hosted on SourceForge.net.

The author has added support for input plug-ins, so now it can open almost any format including MPEG-2, Matroska, Flash Video, Windows Media, AC3, FLIC, QuickTime, MP4, PVN, Redcode RAW.

VirtualDub has spawned several forks, one being the abandoned VirtualDubMod which includes features such as Matroska (MKV), OGM, and Dolby AC-3 support, none of which are present in VirtualDub without the use of third-party plugins.^[27]^[28]^[29] VirtualDubMod is a unification of several earlier projects/forks, including: VirtualDub-MPEG2, VirtualDubOGM, VirtualDubAVS and more.^[28]^[29]^[30]^[31] Another example of a fork is Nandub, which enabled use of Smart Bitrate Control.^[32]

Development stopped as of 2013 ^[1] and the official website's forums closed down in 2015.^[33]

The latest fork is VirtualDub2, in development since 2015.^[34] VirtualDub FilterMod has all the features of the original VirtualDub, plus built-in encode/decode of H.264 and other formats; open and save QuickTime File Format, MP4, Matroska etc.; new and support for high bit-depth (i.e., deep) color formats.^[35]

Past legal issues

Early versions of VirtualDub supported importing of Microsoft's Advanced Systems Format, but this was removed in version 1.3d following an informal phone call from a Microsoft employee claiming that it infringed one of Microsoft's patents. Microsoft never identified any specific patent numbers that it believed to have been infringed, but speculation by others is that {{Cite patent|US|6041345}} might be relevant.^[36]

In August 2006, VirtualDub's German users who hosted copies of VirtualDub, or even linked to them on their web pages, began receiving cease and desist letters from a private individual that claimed to have German word mark on "VirtualDub".^[37] However this issue has been resolved: the word mark in Germany has been deleted^[38] and an injunction has been granted against the former owner of said word mark.^[39]

See also

References

1. ^¹{{ cite web | title = VirtualDub Stable Versions at SourceForge.net | url = http://sourceforge.net/projects/virtualdub/files/virtualdub-win/ | accessdate = October 27, 2013 }}
2. ^{{ cite web | title = VirtualDub features | url = http://www.virtualdub.org/features.html }}
3. ^[https://sourceforge.net/u/virtualdub/profile/ VirtualDub] on SourceForge
4. ^Georgios Diamantopoulos, Sohail Salehi, John Buechler (2009). [https://books.google.de/books?id=apiArMc8t9MC&dq=VirtualDub&hl=de&source=gbs_navlinks_s Learning VirtualDub: The Complete Guide to Capturing, Processing, and Encoding Digital Video], Packt Publishing Ltd, 197 pages (quote taken from back cover blurb)
5. ^¹Gralla, Preston (2009). Capsule review: VirtualDub (32-bit version), PC World, Mar 13, 2009
6. ^¹Fearon, David (2011). How to: convert video footage with VirtualDub, PC & Tech Authority, 18 February 2011
7. ^¹Shrout, Ryan (2017). [https://www.pcper.com/reviews/Graphics-Cards/NVIDIA-FCAT-VR-Preview-New-Performance-Tool NVIDIA FCAT VR - Preview of a New Performance Tool], PC Perspective, March 1, 2017
8. ^Sharninder (2009). [https://www.maketecheasier.com/how-to-compress-a-video-file-with-virtualdub/ How To Compress A Video File with Virtualdub], MakeTechEasier.com, 31st May 2009
9. ^Brinkmann, Martin (2011). How To Change A Video’s Speed With VirtualDub, ghacks.net, June 26, 2011
10. ^¹²Entry [https://kb.speeddemosarchive.com/VirtualDub VirtualDub] on Speed Demos Archive
11. ^Splitting a Video File into a Sequence of Images (virtualdub) on the website of Viscoda, a developer of professional video and digital cinematography software solutions
12. ^Entry [https://developer.valvesoftware.com/wiki/VirtualDub VirtualDub] on the official Valve Developer Community
13. ^Entry [https://appdb.winehq.org/objectManager.php?sClass=application&iId=438 VirtualDub] on winehq.org
14. ^VirtualDub filters index on infognition.com
15. ^VirtualDub-Filter Archive on hlinke.de
16. ^VirtualDub Filter Pack 2014 on techspot.com
17. ^Donald Graft (formerly Neuron2.net): VirtualDub Filters and Hosted Filters and Tools
18. ^Video filtering and compression by MSU Video Group, [https://web.archive.org/web/20150710004842/http://graphics.cs.msu.su/ CS MSU Graphics & Media Lab]
19. ^Andreas Dittrich: VirtualDub Filters and Modified VirtualDub Capture Routine with High Quality Realtime Sample Rate Conversion and Phase Servo Loop (formerly a project at the Kaiserslautern University of Technology where these VDub plug-ins were originally hosted)
20. ^VideoPad Video Plugin Effects, NCH Software
21. ^[https://www.neatvideo.com/download Neat Video v4 (2017) Demo plug-in for VirtualDub]
22. ^DebugMode Wax
23. ^{{cite web |url=http://forums.opensuse.org/new-user-how-faq-read-only/unreviewed-how-faq/429428-howto-install-virtualdub-under-wine-deshaker-plugin.html|title=HowTo install VirtualDub under wine with deshaker plugin|author=oldcpu|accessdate=2010-01-13}}
24. ^http://virtualdub.org/blog/pivot/entry.php?id=152#body
25. ^VirtualDub SDK
26. ^VirtualDub history - virtualdub.org
27. ^{{cite web |url=http://sourceforge.net/projects/virtualdubmod/ |title=VirtualDubMod |accessdate=2009-11-18}}
28. ^¹{{cite web |url=http://www.afterdawn.com/software/video_software/video_tools/virtualdubmod.cfm |title=VirtualDubMod v1.5.10.2 |author=AfterDawn.com |accessdate=2009-11-18}}
29. ^¹{{cite web |url=http://www.videohelp.com/tools/VirtualdubMOD |title=VirtualdubMOD |author=VideoHelp.com |accessdate=2009-11-18}}
30. ^{{cite web |url=http://www.free-codecs.com/download/VirtualDubMod.htm |title=VirtualdubMod 1.5.10.2 |author=Codecs.com |date=2005-08-30 |accessdate=2009-11-18}}
31. ^{{cite web |url=http://www.videohelp.com/tools/Virtualdub-MPEG2 |title=Virtualdub-MPEG2 |author=VideoHelp.com |accessdate=2009-11-18}}
32. ^{{cite web |url=http://nickyguides.digital-digest.com/nandub.htm |title=Nandub / SBC Encoding |publisher=Nicky Pages' Digital Solutions |accessdate=2009-11-18}}
33. ^{{cite web| url=http://forums.virtualdub.org| title=Not found - VirtualDub forums| date=2015-10-12| accessdate=2015-12-12| quote=Sorry, the VirtualDub forums have been closed, and as of this date (22 Oct 2015), it's now down}}
34. ^{{cite web |url=https://sourceforge.net/p/vdfiltermod/code/commit_browser |title=VirtualDub FilterMod / Code / Browse Commits |author=Shekh |accessdate=2017-05-25}}
35. ^{{cite web |url=https://sourceforge.net/p/vdfiltermod/wiki/Home/ |title=VirtualDub FilterMod / Wiki / Home |author=Shekh |accessdate=2017-05-25}}
36. ^Advogato: Microsoft patents ASF media file format, stops reverse engineering
37. ^Illicit word mark registered on "VirtualDub" in Germany - virtualdub.org
38. ^Official status of German word mark 30601877 "VIRTUALDUB"
39. ^"Preliminary injunction granted in regard to German word mark VIRTUALDUB"