Features/BetterWebcamSupport

Better Webcam Support

Summary

Currently many webcams do not work with Fedora out of the box even though Linux driver exist for them, the intent is to fix this.

Owner

• Name: Hans de Goede

Current status

• Targeted release: Fedora 10
• Last updated: (Jul 26 2008)
• Percentage of completion: 60%

Detailed Description

Webcams not working even though there are Linux drivers has 2 causes:

1. The drivers are not in the mainline kernel
2. Those drivers that are in the mainline kernel are often v4l2 while many applications will only work with v4l1. Even v4l2 apps often don't work with v4l2 webcam's as the webcams often have camspecific (compressed) pixelformats and most applications don't support all these,

1) Has been largely fixed by working together with gspca upstream to get gspcav2 cleaned up and merged, Linus has merged gspcav2 (through the v4l-dvb subsystem) for 2.6.27, this vastly improves the amount of supported webcams in 2.6.27. I'm currently working on getting the people behind the micromedia driver for the quite popular sonix sn9c20x based cams, to port their driver to a gspca subdriver and move the cam specific format decoding to userspace as was done with all the gspca decoding routines. The plan is to work together with the various upstreams to port any remaining standalone usb webcam drivers to gspca subdrivers, this is a process which will continue after F-10's release.

2) Has been fixed by creating a utility library which contains all the conversion stuff and v4l1 compatibility functions so that applications can easily be modified to work properly with v4l2 webcams, for more info on his library called libv4l, see: http://hansdegoede.livejournal.com/3636.html

Also refer http://kernelnewbies.org/Linux_2_6_26#head-6d4ee1ddea983f5c8ac491b8685a94ea6fa4132b

Benefit to Fedora

Out of the box working hardware makes for happy end users and good reviews.

Scope

This may require temporarily carrying kernel patches if drivers are clearly moving upstream, but not there yet in time for release.

This requires packaging libv4l for v4l1 emulation and format conversion and making modifications to webcam using applications so that they use libv4l.

Test Plan

I currently have access to the following webcams (in random order):

Webcam	USB ID	Bridge	Sensor	Status
Sweex WC001	0c45:6005	sn9c101	tas5110	works
Sweex WC004	0c45:6011	sn9c101	ov6650	works
Qware EasyCam	0c45:6028	sn9c102	pas202	works *
Intel Create and Share	0733:0401	spca501	integrated	works
Creative Live! VISTA VF0420	041e:4064	ov519	OV7670	works
Trust WB-1400T	093a:2468	pac207	integrated	works
I.T. Works webcam	093a:2460	pac207	integrated	works
Logitech QuickCam IM/Connect	046d:08d9	zc3xx	HV7131R	works *
Labtec notebook cam	046d:08aa	zc3xx	HDCS2020	works *
Creative WebCam Vista	041e:403b	spca561	integrated	works *
Logitech QuickCam Express Plus	046d:092f	spca561	integrated	works *
Philips ???	05a9:0518	ov518	?	Does not work out of tree driver
Philips SPC 200NC	0471:0325	zc3xx	HDCS2020	Does not work
Creative ??	05a9:a511	ov511	?	Does not work out of tree driver
I.T. Works notebook cam	093a:2621	pac7311	integrated	Does not work
Dynalink ???	06be:d001	NW208	integrated	Does not work out of tree driver
Sitecom ??	0c45:62bb	sn0c202	ov7660	Does not work out of tree driver
Silvercrest Webcam 1.3mpix	eb1a:2820	eMPIA em28xx	?	Does not work

(*) works, but does not work well in low light conditions

User Experience

Out of the box working hardware.

Dependencies

None.

Contingency Plan

Don't ship the drivers / wrapper if they aren't ready.

Documentation

Fedora 10 comes with a much cleaned up and ported to v4l2 version of the gspca webcam driver. Many of the supported webcams produce video data in a manufacturer specific video format, Fedora 10 comes with libv4l which handles conversion of these custom formats to the standard video formats that most applications need. All applications in Fedora have been updateds to use libv4l, so when using applications which are part of Fedora things will just work.

For 3th party applications such as for example skype a compatibility library wrapper has been made available. You can make 32 bits applications use this wrapper by typing the following command in a terminal before starting the application from that same terminal: export LD_PRELOAD=/usr/lib/libv4l/v4l1compat.so

And then start the application from that same terminal!

For 64 bit applications the command is: export LD_PRELOAD=/usr/lib64/libv4l/v4l1compat.so

Note that for example skype is a 32 bit applications, so even when running a 64 bit version of Fedora you should use the 32 bit command!

Don't get fooled by the v4l1compat.so name, this library wrapper does not only add v4l1 applicatiom compatibility to v4l2 drivers (such as the new gspca and the uvc driver) but it also handles conversion from cam specific formats to generic video formats for v4l2 applications. If you only want the conversion, without the v4l1 compatibility you can use "v4l2convert.so" instead of v4l1compat.so .

Release Notes

Fedora 10 comes with a much improved support for webcams.

Next to improvements to the UVC driver which was first introduced in Fedora 9 and supports any webcam with a vista compliant logo, Fedora 10 also features a brand new v4l2 version of gspca, an usb webcam driver framework with support for many different usb webcam bridges and sensors.

Userspace support for webcams has also been improved by adding libv4l and updating all webcam using applications to use libv4l, this makes these applications understand the often manufacturer specific and custom video formats emitted by many webcams, esp. by many of the webcams supported by gspca.

For a list of all webcams and applications with which Fedora-10's new webcam support has been tested see the BetterWebcamSupport feature page, for a list of all cams supported by the original version of gspca see the original gspca website. The v4l2 version of gspca in Fedora-10 supports all these webcams and more!

Comments and Discussion

See Talk:Features/BetterWebcamSupport

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