Understanding Mainstream vs Substream in Hikvision Cameras: Which One Do You Need?
When setting up a Hikvision surveillance system, one of the most critical decisions involves selecting the right video stream format. The mainstream vs substream Hikvision debate often confuses beginners and even experienced users. Simply put, the mainstream delivers high-resolution, high-frame-rate video ideal for recording and detailed monitoring, while the substream provides lower-resolution video designed for network efficiency and multi-device viewing. Misunderstanding these two streams can lead to wasted storage, laggy feeds, or poor image quality. This guide will explain the core differences, use cases, and how to optimize both for your specific needs. For a deeper understanding of how to calculate your storage requirements based on these streams, refer to our guide on mainstream vs substream Hikvision storage calculations.
What Is the Mainstream (Main Stream)?
The mainstream (often labeled as “main stream” or “high stream”) is the primary video output from a Hikvision camera. It is configured with the highest resolution, bitrate, and frame rate the camera supports. For example, a 8MP Hikvision camera might have its mainstream set to 3840×2160 at 30 frames per second (fps) with a high bitrate of 8192 kbps. This stream is essential for forensic detail analysis—like reading license plates or identifying facial features. However, because it consumes significant network bandwidth and storage space, it is not suitable for continuous remote viewing over slow internet connections or for real-time viewing on multiple mobile devices. The mainstream is typically recorded on the NVR (Network Video Recorder) for long-term storage and evidence purposes.
What Is the Substream (Sub Stream)?
The substream is a secondary, lower-resolution video stream. Common configurations include 720p or 4CIF, often running at 10-15 fps with a much lower bitrate (e.g., 512 kbps). Its primary purpose is to conserve network bandwidth and enable smooth live preview on mobile apps (like Hik-Connect) or when viewing the camera feed on a monitor with many splits. For instance, when using a DVR or NVR in quad-view mode, the system often uses the substream to reduce processing load. The substream is perfect for basic motion detection, continuous live monitoring, and giving a general view of an area. It sacrifices image quality for performance and reliability.
Key Differences: Quality, Bandwidth, and Storage Impact
The most significant distinction between the two lies in their resource consumption. The mainstream consumes roughly 8-10 times more bandwidth and storage than the substream. For example, recording a single camera on mainstream at maximum settings for 24 hours might require 70-90 GB of storage, while the same camera on substream would use only 10-15 GB. This directly affects your hard drive lifecycle and project costs. If you are calculating long-term retention, understanding the mainstream vs substream Hikvision ratio is crucial. The correct approach is to use the mainstream for recording and critical alerts,