Troubleshoot/Main Stream vs Sub Stream

From Dahua Wiki

Jump to: navigation, search

Main Stream vs. Sub-Stream

Mainstream This is the primary stream that affects data recorded to the hard disk drive and will directly determine your recording quality. The resolution denotes the image size and quality and is therefore very important and should not be overlooked. The frame rate (FPS - Frames Per Second) denotes how many frames are captured each second, with more frames being captured resulting in a smoother, more fluent and higher quality recording - 25FPS = “Real Time”. A higher resolution and frame rate will look best however be aware that it will use up more storage space on the hard disk drive. Setting a higher FPS will also affect your internet bandwidth when viewing a live stream. Users with limited internet speeds may suffer when using higher settings. The bit rate affects both of these settings and is usually dictated by a combination of the above. Lowering the main stream settings is an effective way to increase available recording time.

  • Mainstream provide higher quality video.
  • Higher Resolution
  • Higher FPS
  • Will use more HDD space
  • Higher bandwidth usage.

Sub stream The sub stream or extra stream is a second codec that runs alongside the main stream. This allows you to reduce outgoing internet bandwidth without sacrificing your direct recording quality. The sub stream is often exclusively used by smartphone applications to live stream however some smartphone applications do allow the user to choose the main stream too. Lowering the sub stream settings is often a common solution to no picture availability on a smartphone. Users with limited internet speeds may benefit most from this setting.

  • Lower video quality.
  • Sub stream will save on bandwidth.
  • Save on HDD space.
  • Better adequate for Mobile viewing.
  • Better adequate for remote viewing off local network.
  • Better adequate for slower network speeds


Here is an comparison of Main Stream vs. Sub Stream:

MainStream

mainsub1.png


Sub-Stream

mainsub2.png