i am using compulab's (cm -t3530) eval kit running on angstrom linux.

First the gui of mplayer doesnt work at all. I want to play my webcam.

lsusb gives the following.

Bus 001 Device 009: ID 046d:08f0 Logitech, Inc. QuickCam Messenger

but there is no /dev/video after i type ls /dev

thnx.

Is there a /dev/v4l or /dev/video*? If not, take a look at dmesg and/or /var/log/messages when you plug the device in.

no there is no /dev/v4l


dmesg | less

it shows in the end

usb 1-2.1: new full speed usb device using ethci-omap and address 4
usb1-2.1: new usb device found, idVendor=046d, id product=08f0
usb 1-2.1: new usb device found, idVendor=046d, idProduct=08f0
usb 1-2.1 : new usb device strings:Mfr=0, product=1, serial number=0
usb 1-2.1 : Product:camera
usb 1-2.1 : Configuration #1 chosen from 1 choice

now through command line when i type

mplayer -cache 128 -tv driver=v4l:width=320:height=240: outfmt=i420 -vc rawi420 -vo xv tv://

it gives the following

playing tv://
cache fill : 0.00% (0 bytes)
TV file format detected
selected driver:v4l2
name: video 4 linux 2 input
author: martin......
comment: first try, more to come :-)
v4l2: unable to open '/dev/video0': no such file or directory
v4l2: ioctl ste mute failed: bad file descriptor
v4l2 : 0 frames successfulyy processed: 0 frames dropped.


Exiting .... (end of file)

thnx

It doesn't look like that camera supports standard USB audio/video (UVC). A quick Google search yields a driver for the unit here.

thnx...,

i have one another camera, analog one. when i watch it on host pc i use a tv tuner card in between to watch the video through usb port on vlc player.

how shall i use this on my cm -t3530 kit.

regards.

one more thing.

the logitech canmera works fine on my ubuntu 10.04, without any external driver.

regards

In Linux, drivers are part of the kernel. Each version of the kernel will potentially have different drivers available. In addition, distributions may choose to include out-of-tree drivers (drivers which are not part of the standard kernel). In the case of Ubuntu, they've either chosen to include the driver for your camera in their build, or the kernel they are using is a later revision that has picked up the driver.

You should also be aware that while a kernel may include a given driver, it must be enabled during the build process. The kernel provided with your kit may simply not enable the driver for that device.

There's a further complication in that some drivers are not supported on some architectures. While a device may work on X86/X86_64 it may not be usable on ARM.

thnx

what about analog camera, i said?

but when i attach the usb based tv tuner card, there is no change in the /dev directory.

regards.

I checked the specs for that board, and I don't see a composite input, so no analog camera. The /dev entries are created to provide connections to drivers. No driver, no /dev entry.

thnx macemoneta,

cat /dev/video0 > test.avi results in a file of size few mbs but when i play the file with gnome mplayer, the progress bar moves ahead but no display.

when i take the file to another pc (windows) and play with vlc, same status. it says undefined type audio video.

what does this mean.

regards

Try:

root@cm-t35:/# mplayer tv:// -tv driver=v4l2:device=/dev/video0

MPlayer SVN-r29934-4.3.3 (C) 2000-2009 MPlayer Team



Playing tv://.

TV file format detected.

Selected driver: v4l2

name: Video 4 Linux 2 input

author: Martin Olschewski <olschewski@zpr.uni-koeln.de>

comment: first try, more to come ;-)

Selected device: vivi

Capabilites: video capture read/write streaming

supported norms: 0 = NTSC; 1 = NTSC-M; 2 = NTSC-M-JP; 3 = NTSC-M-KR; 4 = NTSC-443; 5 = PAL-M; 6 = PAL-60;

inputs: 0 = Camera 0; 1 = Camera 1; 2 = Camera 2; 3 = Camera 3;

Current input: 0

Current format: YUYV

v4l2: ioctl set format failed: Invalid argument

v4l2: ioctl set format failed: Invalid argument

tv.c: norm_from_string(pal): Bogus norm parameter, setting default.

Selected input hasn't got a tuner!

v4l2: ioctl set mute failed: Invalid argument

vo: couldn't open the X11 display ()!

vo: couldn't open the X11 display ()!

VO XOverlay need a subdriver

vo: couldn't open the X11 display ()!

[VO_SDL] Using driver: fbcon.

vo: couldn't open the X11 display ()!

==========================================================================

Opening video decoder: [raw] RAW Uncompressed Video

Movie-Aspect is undefined - no prescaling applied.

VO: [sdl] 640x480 => 640x480 Packed UYVY

[VO_SDL] Couldn't get any acceptable SDL Mode for output.

FATAL: Cannot initialize video driver.

VDecoder init failed

Cannot find codec matching selected -vo and video format 0x59565955.

==========================================================================



v4l2: ioctl set mute failed: Invalid argument

v4l2: 0 frames successfully processed, 0 frames dropped.



Exiting... (End of file)

Your camera doesn't appear to support v4l2. Try forcing v4l:
You will need to install libv4l beforehand, if it's not already installed.

while compiling kernel 2.6.32 i selected
--- Device Drivers --- Multimedia support --- Enable Video For Linux API 1 ( DEPRECATED)
--- Video Capture Adapters --- V4l USB Devices--- USB Logitech Qucikcam Messenger (deprecated)

lsusb gives

Bus 001 Device 005: ID 046d:08f0 Logitech, Inc. Quickcam messenger

cat /proc/bus/usb/devices gives

T: Bus=01 Lev=02 Prnt=02 Port=00 Cnt=01 Dev#= 5 Spd=12 MxCh= 0

D: Ver= 2.00 Cls=ff(vend.) Sub=ff Prot=ff MxPS= 8 #Cfgs= 1

P: Vendor=046d ProdID=08f0 Rev= 1.00

S: Product=Camera

C:* #Ifs= 3 Cfg#= 1 Atr=a0 MxPwr=100mA

I: If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=QCM

E: Ad=81(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms

E: Ad=82(I) Atr=03(Int.) MxPS= 1 Ivl=16ms

I:* If#= 0 Alt= 1 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=QCM

E: Ad=81(I) Atr=01(Isoc) MxPS=1023 Ivl=1ms

E: Ad=82(I) Atr=03(Int.) MxPS= 1 Ivl=16ms

I:* If#= 1 Alt= 0 #EPs= 0 Cls=01(audio) Sub=01 Prot=00 Driver=snd-usb-audio

I:* If#= 2 Alt= 0 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio

E: Ad=83(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms

I: If#= 2 Alt= 1 #EPs= 1 Cls=01(audio) Sub=02 Prot=00 Driver=snd-usb-audio

E: Ad=83(I) Atr=01(Isoc) MxPS= 52 Ivl=1ms

LD_PRELOAD=/usr/lib/libv4l/v4l2convert.so mplayer tv:// -tv driver=v4l2:device=/dev/video0

when i use this on ubuntu my mplayer captures the video and displays it but on my arm kit it still


ERROR: ld.so: object '/usr/lib/libv4l/v4l2convert.so' from LD_PRELOAD cannot be preloaded: ignored.

MPlayer SVN-r29934-4.3.3 (C) 2000-2009 MPlayer Team



Playing tv://.

TV file format detected.

Selected driver: v4l2

name: Video 4 Linux 2 input

author: Martin Olschewski <olschewski@zpr.uni-koeln.de>

comment: first try, more to come ;-)

Selected device: vivi

Capabilites: video capture read/write streaming

supported norms: 0 = NTSC; 1 = NTSC-M; 2 = NTSC-M-JP; 3 = NTSC-M-KR; 4 = NTSC-443; 5 = PAL-M; 6 = PAL-60;

inputs: 0 = Camera 0; 1 = Camera 1; 2 = Camera 2; 3 = Camera 3;

Current input: 0

Current format: YUYV

v4l2: ioctl set format failed: Invalid argument

v4l2: ioctl set format failed: Invalid argument

tv.c: norm_from_string(pal): Bogus norm parameter, setting default.

Selected input hasn't got a tuner!

v4l2: ioctl set mute failed: Invalid argument

vo: couldn't open the X11 display ()!

vo: couldn't open the X11 display ()!

VO XOverlay need a subdriver

vo: couldn't open the X11 display ()!

[VO_SDL] Using driver: fbcon.

vo: couldn't open the X11 display ()!

==========================================================================

Opening video decoder: [raw] RAW Uncompressed Video

Movie-Aspect is undefined - no prescaling applied.

VO: [sdl] 640x480 => 640x480 Packed UYVY

[VO_SDL] Couldn't get any acceptable SDL Mode for output.

FATAL: Cannot initialize video driver.

VDecoder init failed

Cannot find codec matching selected -vo and video format 0x59565955.

==========================================================================



v4l2: ioctl set mute failed: Invalid argument

v4l2: 0 frames successfully processed, 0 frames dropped.



Exiting... (End of file)

root@cm-t35:~#

when i checked there is no libv4l directory in /usr/lib.

thnx

As I said, you'll need to get that installed first. Also, use code blocks when pasting information so your comments don't get buried in a wall of text.