min(max((int64_t)floor(start), (int64_t)0), last_sample),
min(max((int64_t)ceil(end), (int64_t)0), last_sample),
samples_per_pixel / Oversampling, channel_->index());
min(max((int64_t)floor(start), (int64_t)0), last_sample),
min(max((int64_t)ceil(end), (int64_t)0), last_sample),
samples_per_pixel / Oversampling, channel_->index());