Скачать или смотреть How to measure video quality? Subjective and objective evaluations. Professional software solutions.

This video explains how to measure video quality. It presents subjective and objective evaluations of video quality. And it introduces several software solutions for professionals.

Script:

1 - How to measure video quality?

2 - There are 2 ways to measure video quality:
1) subjectively (using human observers)
2) objectively (using a software program)

3 - Let's see how subjective and objective evaluations work...
And let's see several professional software solutions...

4 - Chapter 1: Subjective evaluation of video quality

5 - Subjective evaluation consists in presenting video sequences to human observers and collecting their judgments of video quality

6 - But in order to produce reliable results, subjective evaluation tests must respect many rules regarding screen calibration, viewing distance, test protocol, video clips selection, lighting and more (there are several ITU recommendations about how to proceed).

7 - So making reliable subjective tests is a complex task. But the main problem is that subjective evaluation takes a lot of time!

8 - So, how can you measure video quality QUICKLY and or FOR MANY VIDEOS?

9 - The solution is to use a SOFTWARE PROGRAM which will measure video quality, thanks to a VIDEO QUALITY METRIC.

10 - Chapter 2: Objective evaluation of video quality

11 - There are 2 main approaches to measure video quality with a software metric:
1) using a reference signal
2) without using a reference signal

12 - The reference video is the same content as the video under test but without the distortions. Typically, the reference video is the video at the input of the system under test. For example, it is often the video at the input of a video encoder.

13 - First, the reference video and the video under test are synchronized, then perceptual features are extracted and compared. This comparison produces the quality score of the video under test.

14 - For that, you can use our solution "Video Quality Analyzer" (VQA) which works with audio video files.

15 - or our solution "Full Reference Video Quality Monitor" (FRVQM) which works with live signals (HDMI, SDI, IP streaming...)

16 - How to proceed if you don't have the reference videos ?

17 - It's easy! You just have to use a no-reference solution !

18 - With no-reference metrics, you just have to provide the video under test. The video can come from any source: audio video files, HDMI, SDI, IP streaming, desktop capture.

19 - Most no-reference metrics measure distortions by exploring pixel values. Some other metrics use parameters from the encoded bitstream. And hybrid metrics use both pixel values and information from the bitstream.

20 - You can do that with our award-winning solution "Video Quality Monitor" (VQM)

21 - We also offer no-reference solutions
to include in third-party software (SDK)
for OTT
for Linux
to build video monitoring walls

22 - All our products can be evaluated for free!

So CONTACT US if you have needs or questions regarding:
video quality
audio quality
lipsync (audio video synchronization)
TR 101 290 errors on Transport Streams
Quality of Service (Q O S)

23 - To contact us or to receive a free evaluation of our software products, please go to www.acceptv.com

24 - Thank you for your attention