Video4Linux (V4L for short) is a collection of device drivers and an API for supporting realtime video capture on Linux systems.[1] It supports many USBwebcams, TV tuners, and related devices, standardizing their output, so programmers can easily add video support to their applications.
Video4Linux is responsible for creating V4L2 device nodes aka a device file (/dev/videoX, /dev/vbiX and /dev/radioX) and tracking data from these nodes. The device node creation is handled by V4L device drivers using the video_device struct (v4l2-dev.h) and it can either be allocated dynamically or embedded in another larger struct.
Video4Linux was named after Video for Windows (which is sometimes abbreviated "V4W"), but is not technically related to it.[2][3]
While Video4Linux is only available on Linux, there is a compatibility layer available for FreeBSD called Video4BSD. This provides a way for many programs that depend on V4L to also compile and run on the FreeBSD operating system.
V4L had been introduced late into the 2.1.X development cycle of the Linux kernel. Retroactively being renamed to V4L1, it was dropped in kernel 2.6.38.[4]
V4L2 is the second version of V4L. Video4Linux2 fixed some design bugs and started appearing in the 2.5.x kernels. Video4Linux2 drivers include a compatibility mode for Video4Linux1 applications, though the support can be incomplete and it is recommended to use Video4Linux1 devices in V4L2 mode. The project DVB-Wiki is now hosted on LinuxTV web site.[5]
video4linux, short, collection, device, drivers, supporting, realtime, video, capture, linux, systems, supports, many, webcams, tuners, related, devices, standardizing, their, output, programmers, easily, video, support, their, applications, repositorygit, lin. Video4Linux V4L for short is a collection of device drivers and an API for supporting realtime video capture on Linux systems 1 It supports many USB webcams TV tuners and related devices standardizing their output so programmers can easily add video support to their applications Video4LinuxRepositorygit wbr linuxtv wbr org wbr v4l utils wbr gitWritten inCOperating systemLinuxPlatformLinux kernelLicenseGNU General Public LicenseWebsitewww wbr linuxtv wbr orgVideo4Linux is responsible for creating V4L2 device nodes aka a device file dev videoX dev vbiX and dev radioX and tracking data from these nodes The device node creation is handled by V4L device drivers using the video device struct v4l2 dev h and it can either be allocated dynamically or embedded in another larger struct Video4Linux was named after Video for Windows which is sometimes abbreviated V4W but is not technically related to it 2 3 While Video4Linux is only available on Linux there is a compatibility layer available for FreeBSD called Video4BSD This provides a way for many programs that depend on V4L to also compile and run on the FreeBSD operating system Contents 1 History 2 Software support 3 Criticism 4 See also 5 References 6 External linksHistory editV4L had been introduced late into the 2 1 X development cycle of the Linux kernel Retroactively being renamed to V4L1 it was dropped in kernel 2 6 38 4 V4L2 is the second version of V4L Video4Linux2 fixed some design bugs and started appearing in the 2 5 x kernels Video4Linux2 drivers include a compatibility mode for Video4Linux1 applications though the support can be incomplete and it is recommended to use Video4Linux1 devices in V4L2 mode The project DVB Wiki is now hosted on LinuxTV web site 5 Some programs support V4L2 through the media resource locator v4l2 Software support editaMSN Cheese software Cinelerra CloudApp Ekiga FFmpeg FreeJ GStreamer Guvcview kdetv Kopete Libav Linphone LiVES motion MPlayer mpv MythTV Open Broadcaster Software 6 OpenCV Peek PyGame Skype Tvheadend VLC media player xawtv Xine ZoneMinderCriticism editVideo4Linux has a complex negotiation process which caused not all applications having support for all cameras 7 See also editDirect Rendering Manager defines a kernel to user space interface for access to graphics rendering and video acceleration Mesa 3D implements video acceleration APIsReferences edit An Introduction to the Video4Linux Framework How to write a video capture driver 2014 02 02 Retrieved 2014 02 16 Overview of the V4L2 driver framework Archived from the original on 2014 02 21 Retrieved 2013 12 04 Overview of the V4L2 driver framework Path to a Standardized Video Codec API PDF Archived from the original on 2014 01 06 gspca LinuxTVWiki LinuxTV Retrieved 2024 01 12 Schimek Michael H Video for Linux Two API Specification LinuxTV Retrieved 2024 01 12 Open Broadcaster Software OBS obsproject com Corbet Jonathan 2019 07 25 Access to complex video devices with libcamera LWN net Retrieved 2023 02 06 External links editmedia tree development git v4l utils development git Linux Media Infrastructure API V4L2 DVB and Remote Controllers Video4Linux DVB wiki Video4Linux resources Video4BSD a Video4Linux emulation layer Video For Linux V4L sample applications Video For Linux 2 V4L2 sample application Access Video4Linux devices from Java kernel org OpenWrt Wiki Linux UVC driver and tools USB video device class UVC Retrieved from https en wikipedia org w index php title Video4Linux amp oldid 1213915082, wikipedia, wiki, book, books, library,
