---
name: "im_video_v4l1"
section: "3"
platform: "linux"
package: "libvips-dev"
version: "7.20.7-1+b3"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/im_video_v4l1"
---

# im\_video\_v4l1(3)

various image grabbers

## NAME

im\_video\_v4l1 - various image grabbers

## SYNOPSIS

**#include \<vips/vips.h\>**

**int** **im\_video\_v4l1( IMAGE \*im, const char \*device, int channel,** **int brightness, int colour, int contrast, int hue,** **int ngrabs )**

## DESCRIPTION

These functions grab single video frames from various devices. Which of these functions work depends upon how your VIPS has been configured and compiled, and your platform. As a result, they are far from portable ... you want a layer on top of these functions.

**[im\_video\_v4l1(3)](/im_video_v4l1/3.md)** grabs a frame using Video4Linux. It grabs a 24-bit RGB colour image, at the maximum resolution your card allows.

**device** should typically be "/dev/video". **channel** selects the channel to acquire: usually 0 is TV, and 1 is composite video. **brightness,** **colour,** **contrast** and **hue** set grab parameters. Each should be in the range (0 - 32768). 32768 is usually the value you want. **ngrabs** sets the number of frames the card should average. Higher values are slower, but typically less noisy (and slightly softer).

## RETURN VALUE

All functions return 0 on success and -1 on error.