v4l-utils is a collection of various video4linux (V4L) and DVB utilities. libv4l is an accompanying collection of libraries that adds a thin abstraction layer on top of video4linux2 (V4L2) devices. The purpose of this layer is to make it easy for application writers to support a wide variety of devices without having to write separate code for different devices in the same class. It consists of 3 different libraries. libv4lconvert offers functions to convert from any (known) pixel format to V4l2_PIX_FMT_BGR24 or V4l2_PIX_FMT_YUV420. libv4l1 offers the (deprecated) v4l1 API on top of v4l2 devices, independent of the drivers for those devices supporting v4l1 compatibility (which many v4l2 drivers do not). libv4l2 offers the v4l2 API on top of v4l2 devices, while adding support for the application transparent libv4lconvert conversion where necessary.
SANE stands for "Scanner Access Now Easy" and is an application programming interface (API) that provides standardized access to any raster image scanner hardware (flatbed scanner, handheld scanner, video and still cameras, framegrabbers, etc.). The SANE standard is public domain and its discussion and development are open to everybody. The source code is written for UNIX (including Linux) and is available under the GPL, but commercial applications and backends are welcome. The package contains the libraries, net support, and scanimage. The X frontends xscanimage and xcam can be found in sane-frontends.
libbgrab is a video4linux grabbing library to facilitate use of framegrabber cards and webcams through a few function calls. To implement constant throughput and to avoid frame loss delays, triple buffering is used through local buffer copying in a separate grabbing thread. The many demo and utility programs included can display live video to X, convert live video to ASCII, smoothly zoom live-video (using Glide), do some image processing (using MMX), and provide a stand-alone webcam image server.