#ifndef CAPTURE_H #define CAPTURE_H #include #include typedef struct webcam_impl webcam_impl_t; typedef struct { int fd; /* Linux: V4L2 fd. macOS: -1 (unused externally) */ int width; int height; void *buffer; webcam_impl_t *impl; } webcam_t; // Initialize webcam // On Linux: device = "/dev/video0" // On macOS: device = NULL (uses system default camera) or a device name string int webcam_init(webcam_t *cam, const char *device, int width, int height); // Wait for frame to be ready int webcam_wait_frame(webcam_t *cam, int timeout_ms); // Capture frame, dequeue buffer, fill grayscale output buffer int webcam_capture_frame(webcam_t *cam, uint8_t *gray_buffer); // Re‑queue buffer int webcam_requeue_buffer(webcam_t *cam); // Stop streaming and clean up resources void webcam_cleanup(webcam_t *cam); #endif