Synopsis
Real-Time Monitor – RTM – is a multi-channel full reference test solution for monitoring and logging video quality, audio quality, audio/video offset (lip-sync), and audio program loudness. RTM also checks for VANC line data integrity from its uncompressed video inputs.
RTM tests these signal parts, reports the results graphically, and applies test score data in text logs for any duration. It will record incoming audio/video (A/V) segments as uncompressed video when the quality drops below a user-configured threshold applied to each test’s scale of measurement.
The recorded uncompressed A/V sequences from source and test input are then available for playback as a synchronized side-by-side comparison from the RTM system’s full resolution video output or desktop window for event review and resolution. Custom scripted routines via a command line or REST API may be easily applied for product QA regression testing.
Full Transmission Path Testing for OTT, Cable, DBS, IPTV, and Broadcast
Many titles now originate in UHD for SVOD services and continue to be delivered in HD for broadcast origination. Testing delivered quality accurately for the various types of content creates a significant and on-going project to test the various bit rates and delivery resolutions to the home or inter-facility networks. To simplify video quality testing of differing delivery services and receiver types, Video Clarity’s integrated HDMI input option for the RTM 4K system or ClearView Extreme Analyzer allows ease of use with highest accuracy full-reference quality metrics for video, audio, and lip sync.
In these examples the RTM 4K system is input with live source content from either an SDI or ST 2100 network as UHD or multiple HD videos with the resulting delivery samples being input from set top boxes or other service path devices. This way the type of network and delivery path is included in the test for a complete end-to-end quality assessment.
- Create quality average data over short or long duration tests
- Set thresholds for quality to find and record low quality events
- Measure PSNR for high bitrate, low loss codec transmissions
- Use DMOS with MS-SSIM metric for human perceptual accuracy to test home service quality
- Apply up to 16 channel audio test per program with millisecond accurate lip-sync test
- Compare different home service delivery paths with real-time video quality monitoring
Multi-Channel Testing for Statistically Multiplexed Channel Quality and Comparison
For broadcasters and other home entertainment service providers there is a requirement for comparison of quality testing scores for multiple channels being statistically multiplexed using the highly accurate full reference method. This allows channel groups coming from different ownership entities to be compared in real-time with an on-line webpage showing color coded video quality graphs. This way each entity may view a real-time comparison of score data in a browser with a time stamped log of full reference quality test scores that can be used to verify several quality metrics for video, audio, lip sync, and loudness after processing.
In this example one RTM system is used to test four different HD channel services with each tested channel being sourced from the incoming network feed and then each tested channel is sent to the RTM system via IP network directly from the processing device.
Additionally, RTM is shown applying multiple network sources versus processed inputs from the transmission to the studio channel group. This provides quality measurements including the transmission path so that any transmission degradation may be monitored and included in the full reference testing.
- Four tests are shown in a browser page which updates in real-time with each channel having its own distinct color on the graph with user set labels.
- If one or more of the testing channels dips below a user set threshold for quality a recording is automatically made of the source and downstream video pair.
- Additionally, one or more channel’s quality event recordings may be reviewed after the test run via the included RTM Player or during testing via a separate server with RTM Manager and Player installed.
Full Reference Testing In A Media Delivery Network
- Source A/V signal is fed using professional decoder HDSDI or IP to the input #1 on RTM from points A or B as in the diagram below
- The processed A/V feed is then also fed via HDSDI, IP, or converted to HDSDI from HDMI on the back channel delivery device in the headend to input #2 on RTM from points B, C or D
- RTM tests for preset quality levels and also reports quality measurements for all parameters continuously on the desktop, log file and data unicast for as long as required
- RTM can be set to record A/V segments for the duration of the threshold errors with a preset heads and tails length for each recording
- RTM Player application is provided to recall recorded errors and play as synchronized side-by-side uncompressed video on desktop or RTM system video output for review and diagnosis
IP Delivery Service Monitoring – With A Scheduled Quality Test Using RTM
- RTM allows selection of source and processed stream from IP networks
- Source can be from baseband HDSDI or IP – Point A in the above diagram
- Processed feed can be from MPTS or SPTS in IP from point B, C or D
- A program test can be scheduled for single or multiple test instances using RTM Scheduler
- Additional tests of any duration can be preset for demux/decode, time alignment and restart of a monitoring session
- Tests include support for multi-resolution services via selective source scaling
Long Duration Product Audio/Video QA
Testing Functions Applied
In Real-Time
- Measures and reports audio and video quality
- Measures and reports audio offset versus video (lip-sync)
- Meters and reports both inputs for audio loudness
- Measures the VANC lines for complete data versus reference from SDI inputs
- Records both incoming video with audio during below test threshold quality drops
- Also with VANC lines when data is missing or loudness or lip-sync is outside set thresholds
- RTM Player provides side by side playback for detailed error analysis