|
Work item:
|
P.1201 (ex P.NAMS)
|
|
Subject/title:
|
Parametric non-intrusive assessment of audiovisual media streaming quality
|
|
Status:
|
Approved on 2012-10-14 [Issued from previous study period]
|
|
Approval process:
|
AAP
|
|
Type of work item:
|
Recommendation
|
|
Version:
|
New
|
|
Equivalent number:
|
-
|
|
Timing:
|
-
|
|
Liaison:
|
SGs 2, 9, 16
|
|
Supporting members:
|
-
|
|
Summary:
|
Recommendation ITU-T P.1201 provides an overview of algorithmic models for non-intrusive monitoring of the audio, video, and audiovisual quality of IP-based video services based on packet-header information. P.1201 addresses two application areas:
- P.1201.1 specifies the model algorithm for the lower resolution/LR (formerly referred to as low-bitrate, LBR) application area, including services such as mobile TV.
- P.1201.2 specifies the model algorithm for the higher resolution/HR (formerly referred to as high-bitrate, HBR) application area, including services such as IPTV.
The ITU-T Study Group 12 work item that resulted in this new recommendation was formerly referred to as P.NAMS (Non-intrusive parametric model for the assessment of performance of multimedia streaming). Hence, this short-title is retained for easier reference.
The two P.NAMS model algorithms are no-reference (i.e. non-intrusive) models which operate by analysing packet header information as available from respective packet trace data, provided to the model algorithms in the packet capture format (PCAP). Further input information on more general aspects of the stream, such as the video resolution, which may not be available from packet header information, is provided to the model algorithm out-of band, for example in the form of stream-specific side information.
As output, the model algorithms provide individual estimates of audio, video and audiovisual quality in terms of the 5-point ACR (absolute category rating) MOS (mean opinion score) scale. Further, diagnostic information on causes of quality degradations can be made available, too.
Complementary to the P.NAMS models, there are further models described in the P.1202 series of recommendations. These so-called P.NBAMS models are bitstream-based video quality models. The main differences with P.NAMS can be summarized as follows:
- The P.NAMS/P.1201 models provide audio, video and audiovisual quality estimates, while the P.NBAMS/P.1202 only models provides video quality estimates
- The P.NAMS/P.1201 models use packet header information, while the P.NBAMS/P.1202 models exploit further bitstream information, such as coding-related information. As a consequence, the P.NBAMS-models can be more accurate in their quality predictions. In turn, they require non-encrypted streams, to enable the access to payload information. Since the P.1202 models are more complex, they also require more computational power to estimate the video quality.
|
|
Comment:
|
-
|
|
Reference(s):
|
|
|
Historic references:
|
|
Contact(s):
|
|
| ITU-T A.5 justification(s): |
|
|
|
|
First registration in the WP:
2008-05-07 12:26:32
|
|
Last update:
2012-10-19 17:23:59
|
|
