QuickCam Team Forums - All Forums

Frame Rate settings on gspcav1

Mon, 15 Mar 2010 14:50:37 -0700

Hi everybody, I am newbie on webcams and drivers. I wanted to use my webcam on a embedded device which has usb host. I used mjpeg-streamer application with gspca. 2.6.22 version linux kernel run on my board. So I used old gspca driver from http://mxhaard.free.fr/download.html. This driver works up to v4l1 standart. I used mjpegstreamer's gspcav1 plugin and it worked well. But I need to set frame rate for cpu performance issue.

I searched how I can set frame rate on v4l1 standart but I couldnt find any usable informations. May anyone has advice about this issue, or link, or clue :)

Regards,

mgundes

V4L2 API and VIDIOC_S_FMT, VIDIOC_S_EXT_CTRLS

Mon, 15 Mar 2010 12:13:26 -0700

hey guys, so i am working with the v4l2 API and have been coming on an errors incessantly. i was hoping that maybe somebody could help me to explain.

the first is a thing that only occurs sometimes, like 1/5, even with the same made version of the program - that may be the weirdest part. i get the error
VIDIOC_S_FMT error 5, Input/output error

on the code segment

Code:
CLEAR (fmt);

        fmt.type                = V4L2_BUF_TYPE_VIDEO_CAPTURE;
        fmt.fmt.pix.width       = image_width;
        fmt.fmt.pix.height      = image_height;
        fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
        fmt.fmt.pix.field       = V4L2_FIELD_INTERLACED;

        if (-1 == xioctl (fd, VIDIOC_S_FMT, &fmt))
                errno_exit ("VIDIOC_S_FMT");

this is part of my "init_device" function, called after opening the device. any ideas why this is going off??

thanks!

Spec for Fedora and patches

Fri, 12 Mar 2010 19:36:03 -0800

I thought I'd share my spec and patches used to build on Fedora 12. I will be looking to push the package into Fedora properly soon. These are against your latest SVN checkout (90).

Attached.

Manual Zoom

Fri, 12 Mar 2010 06:20:54 -0800

Hello.
How can I manually operate the zoom, by adding two buttons to zoom in / zoom out?
Actually, i use the main properties from the device, but, i need a solution more practice.
Thanks

How does the AWB algorithm work?. Erratic behaviour.

Thu, 11 Mar 2010 09:06:23 -0800

Hello,

I'm new in the forum. I've read several posts and I've found them very useful. Many thanks.

At this moment I'm developing an OpenCV-based application to control an illumination system using a Logitech C600 webcam. The idea is to take snapshots with the camera to make a periodic estimation of the lighting conditions in order to self-adjust the luminic intensity and/or spectrum of the lamps.

I have built a test environment with three different kinds of lamps:

1. A (incandescent lamp) -> Around 2800K
2. TL84 (fluorescent lamp) -> Around 4000K
3. D65 (simulates daylight) -> Around 6500K

I'm trying the AWB of the camera and I've found here that the 0-10000 values that the WhiteBalance control stores could correspond with a 2800-6500K scale, which seems to be quite true, because whenever I switch on the D65 light I can read a value of 9760 for the WhiteBalance (near 10000, so near 6500K) control and if I use the incandescent lamp the reading is 230 (near 0, so near 2800K).

My question is: Would it be possible to use the AWB to measure the colour temperature in a scene? How does the AWB algorithm work for this camera? The reason for this question is that problems arise when I try the TL84 light. There is uncertainty in the reading. I cannot achive the same value everytime, as I can with the other two lights. The reading shows a certain hysteresis. If I light with D65 and then I change to TL84, the reading is between 2000 and 5000. If I try firstly with A and then change to TL84, the reading doesn't achieve those values; it keeps around 1000 or less. Sometimes it even doesn't change the original 230 value. If I begin the experiment with TL84, the camera usually keeps the former value. Actually, the image looks the same even though these differences in the temperature colour exist.

Another particular behaviour that I've found is the next one:

- Scene without any white pixel.
- AWB auto-adjusts to a temperature value I.
- A white target is added to the scene.
- AWB auto-adjusts to a temperature value J.
- The white target is took off the scene.
- AWB keeps value J.

It seems that AWB follows a "best-effort" approach. It tries to shift the camera to the best possible temperature. If we "help it" a little bit, it finds the optimum and it remembers that this is effectively the best temperature while the lighting conditions don't change drastically.

I'll really appreciate any suggestions. Many thanks in advance and I hope my exposition hadn't been too long and/or boring.

Marcos.

VIDIOC_S_EXT_CTRLS

Tue, 09 Mar 2010 12:16:44 -0800

hello, i am working with the v4l2 api and am trying to get the pan/tilt working on my logitech orbit af. there seems to be something the matter with passing small values to the pan/tilt ioctl... check out this code-

Code:
void
pantilt (int fd, int pan, int tilt, int reset) {

    struct v4l2_ext_control xctrls[2];
    struct v4l2_ext_controls ctrls;

    ctrls.ctrl_class = V4L2_CTRL_CLASS_USER;

    if (reset) {
        switch (reset) {
            case 0:
                break;
            case 1:
                xctrls[0].id = V4L2_CID_PAN_RESET_NEW;
                xctrls[0].value = 1;
                break;
            case 2:
                xctrls[0].id = V4L2_CID_TILT_RESET_NEW;
                xctrls[0].value = 1;
                break;
            case 3:
                xctrls[0].id = V4L2_CID_PANTILT_RESET_LOGITECH;
                xctrls[0].value = 3;
                break;
        }
        ctrls.count = 1;
        ctrls.controls = xctrls;
    }
    else {
        xctrls[0].id = V4L2_CID_PAN_RELATIVE_NEW;
        xctrls[0].value = pan;

        xctrls[1].id = V4L2_CID_TILT_RELATIVE_NEW;
        xctrls[1].value = tilt;

        ctrls.count = 2;
        ctrls.controls = xctrls;
    }

    if (ioctl(fd, VIDIOC_S_EXT_CTRLS, &ctrls) == -1) {
        perror("VIDIOC_S_EXT_CTRLS");
        exit(EXIT_FAILURE);
    }
}

now, when i call the function

pantilt(fd, 1000, 0, 0);

the camera moves, as expected. however, when i execute this segment of code:

for (i=0;i

motion detection

Tue, 09 Mar 2010 06:14:12 -0800

Just bought a webcam pro 9000. Unfortunately I did not read the specification before my purchase and have since established from logitech that this webcam is not designed for automatic motion detection (surveillance etc) my primary reason for purchase. My previous logitech PRO 3000 was (which lasted 8 years before giving up). Anybody know if there is a way around this problem (third party software for example) without me buying yet another webcam??

capture of a video display flow

Tue, 09 Mar 2010 04:42:57 -0800

Hello !
Pbm: I have a device that shows a microscope capture through usb port device interface. I would like to capture the video flow to process the images for research purposes.

I've tried several available codes with directshow that works for webcams and similar devices but they don't work because the interface device is not known.

Is there a way to capture the the video flow at a certain point of the system?
Any helpful suggestion is welcome
Thx :)

B500 Webcam on Ubuntu 9.10

Mon, 08 Mar 2010 20:19:48 -0800

My webcam (PN 960-000559) fails to initialize on my ubuntu 9.10 OS. It works perfectly on my other computer, which uses windows 7. I attached the lsusb and dmesg. Help, please.

How i can capture high quality image?

Mon, 08 Mar 2010 06:55:14 -0800

Hello.
I use a Orbit AF Camera and i need to capure photos in high quality. I use the SampleGrabber to obtain it.
Actually, i capture in 1600*1200 with 96 ppp. The resolution it's ok, but, i need more quality in image.
Can anybody help me?
Thanks.

Webcam C500: UVC module fails to initialize webcam randomly in Ubuntu 9.10

Sun, 07 Mar 2010 23:48:58 -0800

Hello,

I recently purchased a C500 Webcam which is UVC-compliant
and after installing it in a clean installation of Ubuntu 9.10
it either worked or not worked after each restart
(not working more often than working).
Yesterday I updated to kernel 2.6.31-20 and it hasn't worked since.
The webcam is always plugged into the PC.
When it's not working there is no /dev/video device present in the system.

lsusb result:

Code:
Bus 001 Device 004: ID 046d:0807 Logitech, Inc.

dmesg regarding UVC:

Code:
[   13.921993] uvcvideo: Found UVC 1.00 device (046d:0807)
[   13.960944] uvcvideo: UVC non compliance - GET_DEF(PROBE) not supported. Enabling workaround.
[   13.961435] uvcvideo: Failed to query (129) UVC probe control : -32 (exp. 26).
[   13.961443] uvcvideo: Failed to initialize the device (-5).
[   13.961531] usbcore: registered new interface driver uvcvideo
[   13.961540] USB Video Class driver (v0.1.0)

messages.log when working:

Code:
Mar  4 09:50:34 efrathome kernel: [   19.874694] uvcvideo: Found UVC 1.00 device (046d:0807)
Mar  4 09:50:34 efrathome kernel: [   19.889117] input: UVC Camera (046d:0807) as /devices/pci0000:00/0000:00:1d.7/usb1/1-4/1-4:1.0/input/input5
Mar  4 09:50:34 efrathome kernel: [   19.889196] usbcore: registered new interface driver uvcvideo
Mar  4 09:50:34 efrathome kernel: [   19.889202] USB Video Class driver (v0.1.0)

messages.log when not working:

Code:
Mar  5 20:06:23 efrathome kernel: [   20.061012] uvcvideo: Found UVC 1.00 device (046d:0807)
Mar  5 20:06:23 efrathome kernel: [   20.118623] uvcvideo: UVC non compliance - GET_DEF(PROBE) not supported. Enabling workaround.
Mar  5 20:06:23 efrathome kernel: [   20.120534] usbcore: registered new interface driver uvcvideo
Mar  5 20:06:23 efrathome kernel: [   20.120540] USB Video Class driver (v0.1.0)

What should I do to make the UVC module recognize the webcam?
I found a somewhat similar thread regarding a different webcam of a different maker here.
However, I'd like to find a solution which doesn't require
compiling the UVC module for every new kernel update.
and of course I'm not sure if the trunk version will solve this problem.

Thank you,
-Nadav

Opening Logitech Orbit from two applications

Sun, 07 Mar 2010 23:09:14 -0800

Hello,

Does anybody know is it possible to open and use Logitech Orbit AF from two applications at the same time?. For instance open it from my DirectShow application, and open it from Logitech software (or skype) and record video and audio.

Regards
Dusan

Web cam for survilliance by using java middleware

Thu, 04 Mar 2010 21:52:29 -0800

Hi,

I am in initial development of R&D Project for video Security Survillance project.

I have written a middle ware in Java for two Single Board computers (SBC).

I want to connect webcam for boards.

I will be sending commands from my middleware to invoke the functions of camera ( like, On, OFF, Zoom, Pan, Tilt etc.,)

Tells me good camera in which the firmware can be used by our middleware.

Thanks

M. Prev Ravanth

Photo Capture from Webcam

Thu, 04 Mar 2010 09:55:59 -0800

Hello.
I need to capture a photo from Orbit AF Webcam.
Anybody have a c# demo to do this?.
Thanks a lot.

Registry setting to detect if camera is plugged/unplugged

Thu, 04 Mar 2010 08:47:49 -0800

I am writing an application which needs to detect whether the camera plugged in or unplugged - this is different from it being installed, as once the software is installed and it is plugged in once, the registry keeps these settings.

I am looking to find the registry location which indicates whether the camera is plugged in the USB slot or not, DYNAMICALLY.

Any help would be greatly appreciated for this time-critical apllication.

Thank you.

feature comparison WebCam PRO 9000

Thu, 04 Mar 2010 04:20:11 -0800

What is the difference between "WebCam Pro 9000" and "WebCam Pro 9000 for Business"?

It is prized identically on the official Logitech Website (U.S.) but the specifications available online are slightly different. I'm especially interested in UVC compatibility and driver-less deployment (for Windows systems).

http://www.logitech.com/index.cfm/webcam...3&cl=us,en

http://www.logitech.com/index.cfm/for_bu...9&cl=us,en

Thanks a lot for clarification,
Christian.

VMSystem.dll Crashed when using QuickCam Pro For Notebooks

Tue, 02 Mar 2010 02:45:33 -0800

Hi,

I am using direct show based application to access the camera. My application will be using direct show based camera capture filter to process the video captured from the camera.

When a logitech camera is in use by my application the thread from VMSystem.dll gets attached to my process and it seems to have crashed right after the graph was started. This happens only some times, because of which my application appears to have crashed to the user.

This crash has happened when using QuickCam Pro For Notebooks, on a XP PC.

Here is the extract of the crash location where the crash has been reported:

EXCEPTION_ACCESS_VIOLATION in module VMSystem.dll at 001B:0740E4C7, exception offset 0000E4C7

OS: Microsoft® Windows XP Professional Edition™ 5.1 Service Pack 3 Build 2600

EAX=0740E4B0 EBX=00001190 ECX=00000000 EDX=00000008 ESI=001AB854
EDI=0745CD20 EBP=0765FA88 ESP=0765F1FC EIP=0740E4C7 FLG=00010202
CS=001B DS=0023 SS=0023 ES=0023 FS=003B GS=0000

Call stack:
0765F1FC: 0765FAB0 0745CD20 0740BF58 0000046D 00000991 00000008
0765FA90: 9687FAF6 42B68BE7 5E0D17A8 73B5B39B 00000002 00000001 - 0001:0000D4C7 VMSystem.dll
00000008: -------- -------- -------- -------- -------- -------- -

Let me know if more details are required.

DirectShow and noise

Mon, 01 Mar 2010 00:00:04 -0800

Hi,

I use DirectShow with a Quickcam Pro 9000. When i get the frame (ISampleGrabberCB.BufferCB), the frame has some noise. If there is contrast in the scene, the frame has more noise (for example a red pen and bleu Handkerchief).

I try with a Logitech C905 too. I have the same problem.

Thanks

control logitech ptz camera pan/tilt using c or c++ o

Thu, 25 Feb 2010 23:08:59 -0800

hi, i am doing a project and is sidering to use a logitech ptz camera.
is there anyone who knows how can i control the built-in servo motor using c or c++. i already finished the code for face recognition, the camera can recognize human face and put a rectangle on the face.
the problem is can i control the built-in servo motor of the camera so that it will automatically pan/tilt when the face is moving.

thank you in advance!!

Video capture from three Webcams simultaneously

Thu, 25 Feb 2010 21:05:03 -0800

Dear webcam experts-
I am trying to use three Logitech Quickcam Deluxe for Notebooks in a custom rig to capture and record to hard drive, the video @ VGA resolution simultaneously. I used a third party software which allows video capture from any number of cameras. My problem is that I was only able to capture and record from all three cameras only when I set resolution at 320x240 for all three cameras. The third party software uses Directshow and not Video for windows. Is there any limitation in windows/Logitech drivers which wouldn't allow video capture simultaneously from the three cameras?

Any information in this regards would be appreciated.

Thanks in advance.

-Kamesh