Function sam3_select_memory_frames

sam3.cpp:9427–9450

Select memory frames for propagation (most recent + evenly spaced).

// Select memory frames for propagation (most recent + evenly spaced).
static std::vector<int> sam3_select_memory_frames(
    const std::vector<sam3_memory_slot>& bank,
    int max_slots) {
    if ((int)bank.size() <= max_slots) {
        std::vector<int> all(bank.size());
        for (int i = 0; i < (int)bank.size(); ++i) all[i] = i;
        return all;
    }
    std::vector<int> selected;
    selected.push_back(0);
    selected.push_back((int)bank.size() - 1);
    int remaining = max_slots - 2;
    if (remaining > 0) {
        float step = (float)(bank.size() - 2) / (remaining + 1);
        for (int i = 0; i < remaining; ++i) {
            int idx = 1 + (int)((i + 1) * step);
            idx = std::min(idx, (int)bank.size() - 2);
            selected.push_back(idx);
        }
    }
    std::sort(selected.begin(), selected.end());
    selected.erase(std::unique(selected.begin(), selected.end()), selected.end());
    return selected;
}

// Compute mask IoU between two binary masks.
static float sam3_mask_iou(const uint8_t* a, const uint8_t* b, int n) {