C++ (Cpp) video_read Examples

Example #1

File: video.c Project: aralbrec/FUZIX

int gfx_draw_op(uarg_t arg, char *ptr)
{
	int err=0;
	int l;
	int c = 8;	/* 4 x uint16_t */
	uint16_t *p = (uint16_t *)(char *)0x5e00;

	map_for_video();
	l = ugetw(ptr);
	if (l < 6 || l > 512){
		err = EINVAL;
		goto ret;
	}
	if (arg != GFXIOC_READ)
		c = l;
	if (uget(ptr + 2, (char *)0x5e00, c)){
		err = EFAULT;
		goto ret;
	}
	switch(arg) {
	case GFXIOC_DRAW:
		/* TODO
		   if (draw_validate(ptr, l, 256, 192))  - or 128!
		   return EINVAL */
		video_cmd( ( char *)0x5e00 );
		break;
	case GFXIOC_WRITE:
	case GFXIOC_READ:
		if (l < 8){
			err= EINVAL;
			break;
		}
		l -= 8;
		if (p[0] > 191 || p[1] > 31 || p[2] > 191 || p[3] > 31 ||
		    p[0] + p[2] > 192 || p[1] + p[3] > 32 ||
		    (p[2] * p[3]) > l) {
			err = -EFAULT;
			break;
		}
		if (arg == GFXIOC_READ) {
			video_read( (char *)0x5e00 );
			if (uput( (char *)0x5e00 + 8, ptr+10, l-2))
				err = EFAULT;
			break;
		}
		video_write( (char *)0x5e00 );
	}
 ret:
	map_for_kernel();
	return err;
}

Example #2

File: v4l.c Project: bilboed/wine

static void V4l_GetFrame(Capture * capBox, unsigned char ** pInput)
{
    if (capBox->mmap)
    {
        if (xioctl(capBox->fd, VIDIOCSYNC, &capBox->grab_buf[capBox->curframe]) == -1)
            WARN("Syncing ioctl failed: %d\n", errno);

        *pInput = capBox->pmap + capBox->gb_buffers.offsets[capBox->curframe];
    }
    else
    {
        int retval;
        while ((retval = video_read(capBox->fd, capBox->grab_data, capBox->imagesize)) == -1)
            if (errno != EAGAIN) break;
        if (retval == -1)
            WARN("Error occurred while reading from device: %s\n", strerror(errno));
        *pInput = (unsigned char*) capBox->grab_data;
    }
}

Example #3

File: application.c Project: martinjaros/augmented-reality-navigation

void application_mainloop(application_t *app)
{
    DEBUG("application_mainloop()");
    assert(app != 0);

    void *data;
    size_t length;
    float att[3], alt, spd, trk, brg, dst;
    char wpt[32];

    float accsum[3];
    float difftime;

    while(1)
    {
        // Process video
        if(!video_read(app->video, &data, &length))
        {
            ERROR("Cannot read from video device");
            break;
        }
        graphics_image_set_bitmap(app->image, data, length);
        graphics_draw(app->graphics, app->image, app->window_width / 2, app->window_height / 2,
                      (float)app->window_width / (float)app->window_height < (float)app->video_width / (float)app->video_height ?
                      (float)app->window_height / (float)app->video_height : (float)app->window_width / (float)app->video_width, 0);

        imu_get_attitude(app->imu, att);
        gps_get_pos(app->gps, NULL, NULL, &alt);

        imu_get_acceleration(app->imu, accsum, &difftime);
        gps_inertial_update(app->gps, accsum[0], accsum[1], accsum[2], difftime);

        // Draw landmarks
        void *iterator;
        float hangle, vangle, dist;
        drawable_t *label = gps_get_projection_label(app->gps, &hangle, &vangle, &dist, att, &iterator);
        while(iterator)
        {
            if((hangle > app->video_hfov / -2.0) &&
               (hangle < app->video_hfov / 2.0)  &&
               (vangle > app->video_vfov / -2.0) &&
               (vangle < app->video_vfov / 2.0)  &&
               (dist < app->visible_distance))
            {
                INFO("Projecting landmark hangle = %f, vangle = %f, distance = %f", hangle, vangle, dist / 1000.0);
                uint32_t x = (float)app->window_width  / 2 + (float)app->window_width  * hangle / app->video_hfov;
                uint32_t y = (float)app->window_height / 2 + (float)app->window_height * vangle / app->video_vfov;
                graphics_draw(app->graphics, label, x, y, 1, 0);
            }
            label = gps_get_projection_label(app->gps, &hangle, &vangle, &dist, att, &iterator);
        }

        // Draw HUD overlay
        gps_get_track(app->gps, &spd, &trk);
        gps_get_route(app->gps, wpt, &dst, &brg);
        graphics_hud_draw(app->hud, att, spd, alt, trk, brg, dst, wpt);

        // Render to screen
        if(!graphics_flush(app->graphics, NULL))
        {
            ERROR("Cannot draw");
            break;
        }
    }
}