Difference between revisions of "Reducing audio video streaming latency"

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= Background =
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= Background =
  
A doctor is performing microscopic surgery. An in-body camera is capturing the video and an LCD is displaying the surgery site. The doctor is operating by looking at the LCD display. Even a latency of 50 ms will effect the doctor's ability to operate. For this RidgeRun customer, the solution was to feed the video though an FPGA and straight to the LCD to minimize latency.
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A doctor is performing microscopic surgery. An in-body camera is capturing the video and an LCD is displaying the surgery site. The doctor is operating by looking at the LCD display. Even a latency of 50 ms will effect the doctor's ability to operate. For this RidgeRun customer, the solution was to feed the video though an FPGA and straight to the LCD to minimize latency.  
  
A police officer has an A/V capture device with an LCD on the back. The police officer occasionally turns on the LCD to verify the camera is working as expected.
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A police officer has an A/V capture device with an LCD on the back. The police officer occasionally turns on the LCD to verify the camera is working as expected.  
  
= What causes latency =
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= What causes latency =
  
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= ALSA or JACK for audio  =
  
= ALSA or JACK for audio =
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The standard Linux library for using APIS can add latency into audio streamings, one solution is to use JACK [http://jackaudio.org/ jackaudio.org/]. Jack is an audio server that can redirect audio from one piece of software to another, using JACK doesn't introduces extra latency into the system, on the other hand, using JACK adds a slight increase in the amount of used CPU
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Revision as of 16:07, 12 August 2014

Background

A doctor is performing microscopic surgery. An in-body camera is capturing the video and an LCD is displaying the surgery site. The doctor is operating by looking at the LCD display. Even a latency of 50 ms will effect the doctor's ability to operate. For this RidgeRun customer, the solution was to feed the video though an FPGA and straight to the LCD to minimize latency.

A police officer has an A/V capture device with an LCD on the back. The police officer occasionally turns on the LCD to verify the camera is working as expected.

What causes latency

ALSA or JACK for audio

The standard Linux library for using APIS can add latency into audio streamings, one solution is to use JACK jackaudio.org/. Jack is an audio server that can redirect audio from one piece of software to another, using JACK doesn't introduces extra latency into the system, on the other hand, using JACK adds a slight increase in the amount of used CPU