## 2 Materials and Methods
### Machine Vision System and DRR  
A computer vision (CV) system for image acquisition, based on four main components (Figure 2) [7; 8; 25; 33], was installed on a Sadrym model 130 (Moron de la Frontera, Spain) pitting machine (see Figure 2b) at a control point near the olive-awl contact moment, where the orientation of the incoming olives can be identified. The DRR machine is a short-tail model suitable for calibers ranging from 140 to 80 olives/kg, with a 3/4\({}^{\prime\prime}\) feed chain width, adjusted by technicians in this case to process a nominal caliber of 80 olives/kg.  
The setup was implemented using a floating PVC tube housing the camera and LED device (Figure 3), triggered by pulses from a magnetic sensor positioned at track level. This sensor operates at a nominal voltage of 12 V, detecting metal at a maximum distance of 8 mm via a flat head. It adapts to the DRR machine's operating speed, recognizing the intervals of metallic separators transporting the olives along the feed chain during industrial operation.  
Figure 3: Computer vision system setup on a Sadrym model 130 DRR machine for olive pitting analysis.  
Figure 2: Diagram of the computer vision (CV) system setup installed on the DRR machine. (**a**) Basic components of the CV system: (MS) magnetic sensor, (LS) LED ring (illumination), (Cam) optical sensor, electronic control panel (ECP—trigger electronics and LED control), and PC + OpenCV/Qt-Creator. (**b**) Location point of CV system in carrier chain Sadrym 130.  
All trigger electronics and data transmission responding to the magnetic sensor signal are managed from an electronic control panel (ECP) connected to the power grid and switched to 12 V (Figure 4) [8].  
The camera incorporates a 1/3\({}^{\prime\prime}\) CMOS MT9V024 sensor housed in an industrial enclosure (The Imaging Source Europe GmbH, Bremen, Germany; model DFK33 GV024; 29 \(\times\) 29 \(\times\) 57 mm) [44]. At full color resolution, the sensor streams up to 87 fps with a 1 ms exposure time, and raw data are transferred via USB-2.0 (480 Mbit s\({}^{-1}\)).  
A Fujinon HF16 HA-1B C-mount lens (FUJIFILM Corporation, Tokyo, Japan; fixed focal length 16 mm, F1.4-F16, manual iris) is used. The lens covers sensors up to 2/3\({}^{\prime\prime}\), so the 1/3\({}^{\prime\prime}\) imager is fully illuminated with negligible vignetting, while the 16 mm focal length provides the required 25 mm \(\times\) 18 mm field of view at the working distance. Its manual iris allows a fixed f-number matched to the constant LED illumination, ensuring exposure stability and eliminating mechanical wear associated with auto-iris drives.  
The lighting unit is a coaxial LED ring comprising 16 unbranded SMD diodes (pur-chased via AliExpress marketplace, Shenzhen, China; 900 lm, 3000 K), capable of 2 ms strobe pulses, synchronized with the global shutter exposure to maximize contrast and freeze motion.  
This design allows the image capture system to avoid overheating, with an ample margin at the olive passage speed, enabling 1:1 photography. For instance, according to the manufacturer, the camera could operate at up to 5220 frames/min--a 48% increase. An example of a capture case during operation is shown in Figure 5.  
Figure 4: Diagram of the electronic control panel (ECP).