Video for Linux Two API Specification
Introduction
Video For Linux Two is the second version of the Video For
Linux API, a kernel interface for analog radio and video capture and
output drivers.
Early drivers used ad-hoc interfaces. These were replaced in
Linux 2.2 by Alan Cox' V4L API, based on the interface of the bttv
driver. In 1999 Bill Dirks started the development of V4L2 to fix some
shortcomings of V4L and to support a wider range of devices. The API
was revised again in 2002 prior to its inclusion in Linux 2.5/2.6, and
work continues on improvements and additions while maintaining
compatibility with existing drivers and applications. In 2006/2007
efforts began on FreeBSD drivers with a V4L2 interface.
This book documents the V4L2 API. Intended audience are
driver and application writers.
If you have questions or ideas regarding the API, please
write to the linux-media mailing list: &v4l-ml;.
The latest version of this document and the DocBook SGML
sources are part of the &v4l-dvb; repository. The online version is
available here: http://linuxtv.org/downloads/video4linux/API/V4L2_API.
&sub-common;
&sub-pixfmt;
&sub-io;
Interfaces
Function Reference
&sub-close;
&sub-ioctl;
&sub-cropcap;
&sub-dbg-g-chip-ident;
&sub-dbg-g-register;
&sub-encoder-cmd;
&sub-enumaudio;
&sub-enumaudioout;
&sub-enum-fmt;
&sub-enum-framesizes;
&sub-enum-frameintervals;
&sub-enuminput;
&sub-enumoutput;
&sub-enumstd;
&sub-g-audio;
&sub-g-audioout;
&sub-g-crop;
&sub-g-ctrl;
&sub-g-enc-index;
&sub-g-ext-ctrls;
&sub-g-fbuf;
&sub-g-fmt;
&sub-g-frequency;
&sub-g-input;
&sub-g-jpegcomp;
&sub-g-modulator;
&sub-g-output;
&sub-g-parm;
&sub-g-priority;
&sub-g-sliced-vbi-cap;
&sub-g-std;
&sub-g-tuner;
&sub-log-status;
&sub-overlay;
&sub-qbuf;
&sub-querybuf;
&sub-querycap;
&sub-queryctrl;
&sub-querystd;
&sub-reqbufs;
&sub-s-hw-freq-seek;
&sub-streamon;
&sub-mmap;
&sub-munmap;
&sub-open;
&sub-poll;
&sub-read;
&sub-select;
&sub-write;
&sub-driver;
&sub-libv4l;
&sub-remote_controllers;
&sub-compat;
Video For Linux Two Header File
&sub-videodev2-h;
Video Capture Example
&sub-capture-c;
Video Grabber example using libv4l
This program demonstrates how to grab V4L2 images in ppm format by
using libv4l handlers. The advantage is that this grabber can potentially work
with any V4L2 driver.
&sub-v4l2grab-c;
&sub-fdl-appendix;
&sub-media-indices;
&sub-biblio;