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— CCTV Storage · 8MP

Hikvision DS-2CD2T87G2-L (ColorVu 8MP) storage & retention

Problem. A fleet of Hikvision DS-2CD2T87G2-L (ColorVu 8MP Bullet) cameras recording continuously puts real weight on the storage decision — 8MP frames at a typical 16 Mbps bitrate accumulate fast, and under-sizing the NVR is the single most common CCTV retrofit mistake. The question a buyer actually needs answered is how many terabytes a 30-day continuous-recording policy demands, and what class of head-end that quantity of storage implies.

Answer. At 16 cameras recording continuously for 30 days, this preset returns roughly 83 TB of usable storage — about 173 GB per camera per day — which sits comfortably within an Entry NVR architecture class. The figure scales linearly, so doubling either the camera count or the retention window roughly doubles the storage requirement.

02 / In depth

How this preset reads — the engineering view.

The DS-2CD2T87G2-L (ColorVu 8MP Bullet) records at 8MP using H.265+, with a typical bitrate of 16 Mbps at 25 fps. That works out to roughly 173 GB per camera per day of continuous recording — the single largest input to the storage sum. H.265+ is a smart codec that layers scene-change and region-of-interest compression on top of standard H.265, trimming bitrate further versus plain H.264 for the same resolution and frame rate, without the calculator needing to model that saving separately — it is already reflected in the 16 Mbps working figure.

Scaling from one camera to a fleet is simple multiplication: 16 cameras × 30 days at ~173 GB/camera/day lands at approximately 83 TB. Extending retention to 60 or 90 days, or adding more cameras, scales the total in direct proportion — there is no discount or penalty for scale in the underlying arithmetic. At 16 cameras and this storage envelope, the head-end sits in the Entry NVR class rather than requiring a distributed or enterprise storage architecture.

To use the calculator for this camera, drag the camera-count slider and the retention-window field and watch the storage total recompute live. Switching the recording schedule from continuous ('always-on') to a motion-triggered option applies a duty-cycle factor that reduces effective recording hours per day, cutting the storage total accordingly — useful for comparing a leaner motion-only policy against the always-on baseline shown here.

The calculator does not decide real-world scene-activity variance (a busy entrance bitrate-averages higher than a quiet corridor even on the same camera model), RAID or redundancy overhead (a real BOQ adds capacity for RAID 5/6 rebuild headroom), a failover or archive storage tier, whether the network and NVR write path can sustain the aggregate throughput, or the exact drive count and capacity plan for the array.

What this preset deliberately does not solve

  • The 16 Mbps figure is a scene-average working bitrate — busier scenes with more motion or detail push real-world bitrate higher than this preset assumes.
  • This preset models continuous (always-on) recording; switching to a motion-triggered schedule reduces the storage total and is not reflected in the headline 83 TB figure.
  • The output is raw usable storage before RAID or redundancy overhead, which a real BOQ adds on top.

How this preset differs from its siblings

The DS-2CD2T87G2-L's 8MP sensor and 16 Mbps typical H.265+ bitrate sit well above a standard 4MP camera's typical bitrate, so the per-camera-per-day storage figure (~173 GB) is materially higher than 4MP presets elsewhere in this tool at the same fps and schedule. That difference alone shifts the resulting head-end class and total fleet storage enough that this camera warrants its own preset rather than being approximated from a lower-resolution model.

03 / Hydrated calculator

Try the configuration — live.

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