SCW uses H. It requires a plugin in all cases. Sadly, it still faces the same patent issues, and still doesn't have support in Firefox or Chrome.
We're currently working on a piece of companion software that runs in the cloud, allows you to store video offsite, converts the video to whatever your browser supports, and performs more sophisticated video analytics than are possible without supercomputers. It will have a subscription fee, however.
The biggest and most important reason that we picked H. You can use a program like Final Cut Pro to convert video into one of these open source standards, but there's not yet a way to record directly - at least not using a hardware accelerated method required for a low-power device like a security camera. In comparison to H. This focuses nearly all of the processing power of the camera on the areas of the screen with activity with a much higher accuracy than H The processing power required to create H.
The image quality differences of H. Our cameras are backwards compatible. All SCW products can use H. New to security camera systems? Confused by Analog vs IP? Bullet vs Dome? Indoor vs Outdoor? Don't even know what PTZ means? How a patent war changed how you can view your security cameras. Block Oriented Compression Example. And they were wrong. This also didn't work.
Google backtracks and allows some use of H. Why did SCW choose H. Just Getting Started with Security Cameras? Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?
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Improve this answer. Roman R. But still, it makes for my application ahuge difference if I can save 50 secs of stream or 3 minutes. Equally important, the complexity of a scene can change depending on the time or day or the time of year. For instance, a group of people meeting in a lunch room is a far more complex scene than that same lunchroom on Saturday when the office is closed. To maintain the same quality, all CODECs will require more bandwidth for the period when a group of people meet than when the lunch room is unoccupied.
More complex scenes are often the most important scenes within video surveillance as they reflect activity and potentially problems or at least activities of interest. In the video below we show you bandwidth consumption differs for a variety of common scenes:The impact of complexity on bandwidth differs significantly between MJPEG and H.
In our tests, with MJPEG, the difference in bandwidth needed for the least to most complex scenes only differed by a factor of 3. However, in our tests with H. The H. It is a fallacy that MJPEG's bandwidth demands are constant or that the stream size does not vary with complexity. They can safely do this because the variance in bandwidth size due to complexity is relatively limited for MJPEG.
However, this does expose some modest level of quality loss or bandwidth inefficiency. Even though H. While our tests show that fixed image size can be used fairly safely for MJPEG without thought or planning, such an approach is risky and problematic for H. With Constant Bit Rate, the IP camera will maintain the same bandwidth level regardless of the scene's complexity. If bandwidth is insufficient to match the complexity, quality will be sacrificed.
With Variable Bit Rate, the IP camera will keep adjusting the bandwidth level to hold the quality steady with the scene's complexity. In the video below, we show how VBR bit rate changes rapidly when the scene changes but with CBR it always stay the same:. Resolution does not ensure quality. This is critical to appreciate and an important practical issue in the use of CBR streaming.
All video in surveillance is compressed and that compression loses some of the original data called lossy compression. What's key here is how 'lossy' the compression is.
This is controlled by the quantization level - The higher the level, the lossier the compression and the worse visibly the video will appear. This can be accomplished in two ways - reduce visible quality of a given frame or reduce the number of frames streamed.
Manufacturers vary in what options they provide and what the default choice is. In the video below, we show examples of different manufacturers naming conventions, defaults and options for CBR quality degradation. As a side note, with CBR, if the bandwidth level is 'too high' for the a low complexity scene, the quantization level will be lowered, providing for a more lossless compression. If the IP camera provider using CBR decides to reduce the visible quality of a given frame this will be done through an increase the quantization level.
Raising the quantization level is at the heart of why H. In the video below, we show H. Using a stream analyzer, we show how the quantization level varies and how this is correlated with changes in visible video quality. Stream Analyzer : In the screencast below, we used a free stream analyzer from Avinaptic to examine the H.
Download the Avinaptic software and the sample stream we analyzed [link no longer available]. The choice has significant impacts on bandwidth savings, visual quality and infrastructure planning. If you use CBR, you simplify the planning of your infrastructure - specifically it becomes simple to design and ensure that your IP video works properly over your networking devices e. Your infrastructure needs are a simple multiplication of total streams times stream size.
The two major downsides of using CBR are 1 potential quality degradation or 2 infrastructure inefficiency. If you set the CBR rate too low for your scene's complexity, you will lose either frames or quality levels as described above.
If you set the CBR rate too high, you will waste storage and require more networking resources than needed for your video.
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