Access violation

[Aleksandr Tumanyan]

Hello,
Tobii Eyetracker 4C,
the sample from Stream Engine:

#include <tobii.h>
#include <tobii_streams.h>
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <string.h>
//#pragma warning(disable : 4996) 

void gaze_point_callback(tobii_gaze_point_t const* gaze_point, void* user_data)
{
    if (gaze_point->validity == TOBII_VALIDITY_VALID)
        printf("Gaze point: %f, %f\n",
            gaze_point->position_xy[0],
            gaze_point->position_xy[1]);
}

static void url_receiver(char const* url, void* user_data)
{
    char* buffer = (char*)user_data;
    if (*buffer != '\0') return; // only keep first value

    if (strlen(url) < 256)
        //printf(strlen(url))
        strcpy(buffer, url);
}

int main()
{
    tobii_api_t* api;
    tobii_error_t error = tobii_api_create(&api, NULL, NULL);
    assert(error == TOBII_ERROR_NO_ERROR);

    char url[256] = { 0 };
    error = tobii_enumerate_local_device_urls(api, url_receiver, url);
    assert(error == TOBII_ERROR_NO_ERROR && *url != '\0');

    tobii_device_t* device;
   <strong> error = tobii_device_create(api, url, TOBII_FIELD_OF_USE_INTERACTIVE, &device);</strong>
    assert(error == TOBII_ERROR_NO_ERROR);

    error = tobii_gaze_point_subscribe(device, gaze_point_callback, 0);
    assert(error == TOBII_ERROR_NO_ERROR);

    int is_running = 1000; // in this sample, exit after some iterations
    while (--is_running > 0)
    {
        error = tobii_wait_for_callbacks(1, &device);
        assert(error == TOBII_ERROR_NO_ERROR || error == TOBII_ERROR_TIMED_OUT);

        error = tobii_device_process_callbacks(device);
        assert(error == TOBII_ERROR_NO_ERROR);
    }

    error = tobii_gaze_point_unsubscribe(device);
    assert(error == TOBII_ERROR_NO_ERROR);

    error = tobii_device_destroy(device);
    assert(error == TOBII_ERROR_NO_ERROR);

    error = tobii_api_destroy(api);
    assert(error == TOBII_ERROR_NO_ERROR);
    return 0;
}

error on bold stroke:

tobii_device_t* device;
error = tobii_device_create(api, url, TOBII_FIELD_OF_USE_INTERACTIVE, &device);
assert(error == TOBII_ERROR_NO_ERROR);

Необработанное исключение по адресу 0x6CC93CE5 (tobii_stream_engine.dll) в Project5.exe: 0xC0000005: нарушение прав доступа при записи по адресу 0x00000001.

Scan

How do I fix this error?

Best regards,
Aleksandr

[Grant [Tobii]]

Hi @aleksandrtumanyan, sorry to hear about your issues. Issues related to the error code 0xC0000005 typically refer to corrupt system files (or faulty RAM)

Firstly, you can try redownloading the stream engine components and if that doesn’t work, try running the Windows System File Checker (SFC) tool via the Command Prompt:

sfc /scannow

Might also be worth running a RAM test tool to check for any potential memory problems. Please go through this and let us know how you get on. Best Wishes.

[Aleksandr Tumanyan]

Hi Grant, Thank’s
test sfc – OK
test RAM – OK
The error persists.
What else can I do?

Best regards,
Aleksandr

[Grant [Tobii]]

Hi @aleksandrtumanyan, sorry to hear that. Is it possible for you to test this on another system? It seems like is quite likely to be related to your specific setup..hopefully we can pin down the source. Thanks.

[Aleksandr Tumanyan]

Hi, Grant,
What is the sequence of tobii activation? Insert usb and that’s it?
Do I need to run the standard
Tobii_Eye_Tracking_Core_v2.16.5.156_x86
program before starting my C-program? Or should this program be disabled?

Best regards,
Aleksandr

[Grant [Tobii]]

Hi @aleksandrtumanyan, yes you will need to have the Tobii Core Software installed, a user profile created and a calibration successfully run. Can you confirm that the eye trackers works normally with the Core Software? ie Mouse warp interaction, etc?

[Aleksandr Tumanyan]

Hi Grant, yes, eye tracker works normally with the Core Software.

[Grant [Tobii]]

Hi @aleksandrtumanyan, after consulting with the developers, we have been unable to identify the source of the error. At this stage, could you try to package the project that may be try to run it on our own system please? Out of curiosity, do you get the same issue if you try to run the c# sample?

[Aleksandr Tumanyan]

Hi Grant, I’ll need some time ..
It is unstable, now it gives an error here

char url[256] = { 0 };
error = tobii_enumerate_local_device_urls(api, url_receiver, url);
assert(error == TOBII_ERROR_NO_ERROR && *url != ‘\0’);

Assertion failed: …
Completed with code 3

[Aleksandr Tumanyan]

Hi, Grant, everything works on another machine, I will look for the difference ..

[Grant [Tobii]]

HI Alex, thanks for the update, good to know.. keep us in the loop as to how you get on. Best wishes.

[DavidDang]

Hi,Grant
I meet the same problem on my linux computer,while the EyetrackerManager can detect the device.

char url[256] = { 0 };
error = tobii_enumerate_local_device_urls(api, url_receiver, url);
assert(error == TOBII_ERROR_NO_ERROR && *url != ‘\0’);

Do you know why?

[Grant [Tobii]]

Hi @daviddang. do you have the relevant Linux drivers and configuration software installed?

[Author]

Posts