- Created by Elisa Diel (Unlicensed) on 10 Aug 2022
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TR101 analysis can be added to an input stream for the monitoring of the TS while in operation. The analysis can be used to check the integrity of the TS, as well as perform content analysis to identify frozen video, blank picture, silent audio, low video quality and audio clipping. The TR101 analysis covers priority 1 and 2 messages.
To enable the TR101 analysis follow the instructions in the Adding TR101 Analysis to the Input Stream section. After enabling the analysis, the stream will include the P1 (high priority error) and P2 (low priority error) status, indicating is there are P1 or P2 messages.
To open the analysis window, click the stethoscope () icon.
The TR101 Analysis window includes the following elements:
Stream Information Statistics Panel
The stream information statistics panel displays the following accumulative statistics about the stream:
Parameter | Description |
---|---|
Status | |
TR101 performance drops | |
CQA performance drops | Specify the UDP port to be used for streaming the video. |
Error | Specify the UDP port to be used for streaming the audio. |
PAT | The Program Association Table (PAT), which only appears in PID 0x0000 packets, tells the decoder what programs are in the TS and points to the Program Map Tables (PMT) which in turn point to the component video, audio and data streams that make up the program. If the PAT is missing then the decoder can do nothing, no program is decodable. |
Min bitrate | The minimum bitrate of the PAT packets |
Max bitrate | The maximum bitrate of the PAT packets |
Avg bitrate | The average bitrate of the PAT packets |
CC errors | Indicates if continuity count errors were found. For this indicator three checks are combined. The preconditions "Incorrect packet order" and "Lost packet" could cause problems for IRD which are not equipped with additional buffer storage and intelligence. It is not necessary for the test equipment to distinguish between these two preconditions as they are logically OR-ed, together with the third precondition, into one indicator. |
Scrambled | Indicates if the packet is encrypted. |
Packets | The number of packets which are related to the PAT (with the same PID – 0) |
NULL | Null (stuffing) packets. In order to ensure that the stream maintains a constant bitrate, a multiplexer may need to insert some additional packets. The PID 0x1FFF is reserved for this purpose. The payload of null packets is all zeroes, and the receiver is expected to ignore its contents. Null packets are indicated by PID 8191 (all 1s). |
Min bitrate | The minimum bitrate of the NULL packets |
Max bitrate | The maximum bitrate of the NULL packets |
Avg bitrate | The average bitrate of the NULL packets |
Packets | The number of packets which are related to NULL (with the same PID 8191) |
Programs | The Transport Stream can include one program (SPTS) or multiple programs (MPTS). Every program is described by a program map table (PMT). The elementary streams associated with that program have PIDs listed in the PMT. Another PID is associated with the PMT itself. |
PMT PID | Indicates the PID number of the program map table PMT. |
Min bitrate | The minimum bitrate of the packet which is related to the PMT PID. |
Max bitrate | The maximum bitrate of the packet which is related to the PMT PID. |
Avg bitrate | The average bitrate of the packet which is related to the PMT PID. |
CC errors | Indicates if continuity count errors were found in the packets that are related to the PMT PID. For this indicator three checks are combined. The preconditions "Incorrect packet order" and "Lost packet" could cause problems for IRD which are not equipped with additional buffer storage and intelligence. It is not necessary for the test equipment to distinguish between these two preconditions as they are logically OR-ed, together with the third precondition, into one indicator. |
Packets | The number of packets which are related to the PMT PID. |
PCR PID | Indicated the PID value that includes the program clock reference (PCR). The PCR is used to enable a decoder to present synchronized content, such as audio tracks matching the associated video. |
PCR | Indicates the program clock reference (PCR) value. |
Accuracy | Indicates the difference between the actual PCR value and the value it should have in the TS represented by the byte index for its actual position. For example, if the calculated PCR (derived from adding the value to the previous packet) is the same as the actual PCR value, the Accuracy value will be '0'. |
Deviation | Indicates the frequency deviation. |
Delay | Indicates the delay in delivery. |
OJ max | Indicates the maximal Overall Jitter, which are variation in delays. |
OJ Dev | Indicates the deviation in the overall jitter. |
Bitrate | The bitrate of the specific PCR PID packets. |
Elementary PIDs | Below the Elementary PIDs level are all the different programs that are included in the stream. |
Type | The type of program. |
Min Bitrate | The minimum bitrate of the packet which is related to the Elementary PID. |
Max Bitrate | The maximum bitrate of the packet which is related to the Elementary PID |
Avg Bitrate | The average bitrate of the packet which is related to the Elementary PID |
Declared Bitrate | The bitrate value which that was set on the encoder. (H264 streams only) |
HDR Buffer Size | The HRD buffer size that was set on the encoder. (H264 streams only) |
CC errors | Indicates if continuity count errors were found in the packets that are related to the Elementary PID. |
Scrambled | Indicates if the packet is encrypted. Possible values include: Not scrambled, scrambled with even key, scrambled with odd key. |
PIC Timing | Indicates the time as it is appears in the last PIC Timing SEI message. (H264 streams only) |
PTS | The Presentation Time Stamp (PTS) that the analyzer has captured on the Element stream. The PTS is only accessible if the TS is not scrambled |
DTS | The Decode Time Stamp (DTS) that the analyzer has captures on the Element stream. The Decode Time Stamp (DTS) indicates the time at which an access unit should be instantaneously removed from the receiver buffer and decoded. It differs from the Presentation Time Stamp (PTS) only when picture reordering is used for B pictures. If DTS is used, PTS must also be provided in the bit stream. PTS (or DTS) is entered in the bitstream at intervals not exceeding 700 mS. ATSC further constrains PTS (or DTS) to be inserted at the beginning of each access unit. |
Total Bytes | The total amount of bytes that has passed through the current elementary stream. This includes the Transport Stream Headers. |
Packets | The total amount of packets that have passed through the current elementary stream. |
Width | The frame resolution width setting. |
Height | The frame resolution height setting. |
FPS | The Frames Per Second setting. |
Interlaced | Indicates whether the video is interlaced or not. |
Chroma | Indicates the Chroma Subsampling. |
CEA-608/708 captions | A counter that shows how many SEI messages with type 4 (user_data_registered_itu_t_t35) were detected so far. (H264 and HEVC streams only) |
Content | Indicates the status of the content. This indicator is enabled when content analysis is turned on. Possible values:
|
ePSNR | Estimated PSNR - an estimation of the video quality. values in dB |
PSNR | Actual PSNR as calculate by the encoder. available on software transcoded H264 streams only (when user turned it on under the settings tab). values in dB. |
Frames | Indicates the number of frames. This indicator is enabled when content analysis is turned on. |
Frame Duration max/min/avg (ms) | Indicates the maximum, minimum, and average frame duration in milliseconds. |
GOP Duration max/min/avg (ms) | Indicates the maximum, minimum, and average GOP duration in milliseconds. |
GOP structure | Indicates the GOP structure, by showing the first 10 frame types in the last GOP. For the example, IPBBBPBBBP. |
P1/P2 Errors
The P1/P2 errors panel displays data about Priority 1 and Priority 2 errors that were found in the stream during the analysis. The table displays the following information for each error:
- Indicator – the indicator for which the error was generated.
- #Errors – the total number of errors that were generated.
- Last error – the time in which the last error was generated.
- Error message – the message that was generated with the error.
The statistics regarding the following Priority 1 and Priority 2 errors are displayed:
Parameter | Description |
---|---|
Priority 1 | |
TS_sync_loss | Indicates a loss of synchronization with the TS. When 5 sync bytes have been acquired, the decoder is considered synched, but a loss of just 2 sync bytes indicates a loss of sync. |
Sync_byte_error | If the sync byte is not equal to 47 hexidecimals, then a sync byte error occurs. The system then looks for the reoccurrence of the sync byte (which must be 47 hexadecimals) every 188 bytes. |
PAT_error | The program association table (PAT) is the only packet with packet ID (PID) Hex 0000, and it must occur at least every 0.5s to keep this error from occurring. Every program within the TS is listed in the PAT; if it is missing, then no programs can be decoded. |
Continuity_count_error | This error occurs when any of the following faults happen — incorrect packet order, a packet occurs more than twice or a packet is lost. |
PMT_error | This error can occur if the program map table (PMT) does not come up at least every 0.5s on the PID that is referred to in the PAT. |
PID_error | When TSes are remultiplexed, this can occur if any PID doesn’t refer to an actual data stream. |
Priority 2 | |
Transport_error | This flag is set in the TS header by the demodulator if it can't correct errors in the stream. |
CRC_error | This indicates that a CRC error (data corruption) occurred in any of the following tables — CAT, PAT, PMT, NIT, EIT, BAT, SDT or TOT. |
PCR_error | This flag is raised if the primary clock reference (PCR) is not seen for more than 100ms. The time interval between two consecutive PCR values should be no more than 40ms. This type of error can cause the decoder to lose lock on the 27MHz clock. |
PCR_accuracy_error | This error can occur when the PCR accuracy of the selected program is outside the range of ±500ns. |
PTS_error | This occurs when the presentation time stamp (PTS) repetition is more than 700ms. The PTS is contained in the MPEG-2 program stream and is used to aid the decoder in presenting the program on time, at the correct speed and synchronized. The PTS is compared to the PCR. |
CAT_error | This is used for conditional access programs (paid programming). |
Content Analysis
The Content Analysis errors panel displays that were found in the stream as part of Zixi's content analysis. To see this table, you must enable the content analysis, by following the instructions in the Enabling Content Analysis section. The table displays the following information for each error:
- Indicator – the indicator for which the error was generated.
- #Errors – the total number of errors that were generated.
- Last error – the time in which the last error was generated.
- Error message – the message that was generated with the error.
Parameter | Description |
---|---|
Frozen_video | Occurrence of frozen video, i.e. no motion, for a duration of approximately 60s or longer. |
Blank_picture | Occurrence of blank frames of any color for a duration of approximately 60s or longer. |
Silent_audio | Occurrence of silence (dBFS < -90) on AAC or MPEG audio with a duration of about 30s or longer. |
Low_video_quality | The estimated video quality, which is based on the Peak signal-to-noise ratio (PSNR) is below the 20dB threshold and therefore considered as poor. |
Audio_clipping | Occurrence of clipped audio upon occurrence on AAC or MPEG audio. |
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