User manual

Tree view - PIDs

In this section each PID is represented, independent of the PSI information. That means some PIDs that are not present in the PSI are still shown.

For ease of recognition each PID gets assigned a name, based on the PSI information. This can look something like 'Nederland 1 ITU-T Rec. H.262 | ISO/IEC 13818-2 Video or ISO/IEC 11172-2 constrained parameter video stream, PCR for 1101 (Nederland 1)'. From the PSI it is concluded this PID contains the video Nederland 1, and also the PCR signal.

PSI Data

PSI data is shown as raw tables, without interpretation. This may assist in analyzing some private tables (like Conditional Access tables). Sometimes a PID contains PSI data, but not a valid table structure. For instance, for PID 21 on a DVB-T stream. This is used for network synchronization. The data for this PID is not shown.

PES Data

For PES data the stream_id is used as indicator what type of data we are dealing with. When the data is not encrypted some more general information is shown.

Some types are (partially) supported for detailed inspection. To use this, select the PID to be inspected, right click, and select 'parse PES data' from the popup menu. This will take a few seconds while DVB inspector rescans the file. Then an extra sub folder 'PES Data' will be added to the PID. Supported data types are MPEG2 Video, MPEG2 Audio, H.264 Video, EBU Data (Teletext, VPS and WSS) and DVB subtitles.

Video MPEG2

Above an example of a MPEG2 video stream. This stream has one frame per PES Packet, sometimes streams have an entire Group Of Pictures per PES packet (see below), or even one single section.

Frame structure

When the "PES Data" node is selected for a MPEG2 video stream the right panel will show a graph with the size and transmission order of the different frame types (IBP).

Preview

When a PES packet is selected which contains an I-Frame (or of Group Of Pictures containing an I-Frame) a preview of the I-Frame will be shown in the right panel. This preview has the same dimension in pixels as the MPEG-frame, so aspect-ratio information is ignored.

Video H.264

Above an example of the structure of a H.264 (or ISO/IEC 14496-2) video stream.

Audio MPEG

Example of the audio packets for TV service Nederland 1.

RDS via UECP

For audio streams where a ancillary_data_descriptor in the PMT indicates the presence of "RDS via UECP" data the UECP data is shown.

Audio AC3 & E-AC3

EBU Data / Teletext / VPS / WSS

This shows data for PIDs that contain Vertical Blanking Information (VBI) according to EN 301 775. For streams of type 'private_stream_1', and the first byte of the PES packet (data_identifier) is between 0x10 to 0x1F or 0x99 to 0x9B. Be carefull, sometimes other private data is wrongly interpreted as EBU data, so the displayed information will be meaningless.

Sometimes teletext, VPS and WSS information is transmitted within a single PID, sometimes different PIDs are used.

In this section first the PES packets are shown in the order of transmission (the "RAW" data), then the interpretation of the EBU data is shown for teletext, VPS and WSS data.

Teletext

Remember this is not a teletext decoder for viewing pages as they should be presented, but an analyzer, to show the logical structure of the data. For the details of teletext see EN 300 706.

A teletext service is organized into 8 magazines, numbered from 0 to 7. Magazine 0 contains the pages shown with page number 800. Each magazines can contain 256 pages, numbered from 0x00 to 0xFF. Each page can have sub pages. Teletext data is transmitted line by line(packet). Most lines belong to a specific page, but some belong to a magazine, or just to the entire service.

Lines with packet address 30 and 31 belong to the service. Line 30, designation code 0 identifies the initial teletext page, and identifies the station. It also contains the actual time for PDC.

Line 30, designation code 2 identifies the initial teletext page, and identifies the current program for PDC. Lines with packet No 31 are used for private data broadcasting.

This is some of the data for magazine 1. First is the line 29, which contains magazine related page enhancement data. It defines the background color for this magazine, to be used for level 2.5 decoders.

Page

When in the tree a page (or sub page) is selected a preview of that page is shown in the right panel. Teletext level 2.5 is (partially) supported in the preview.

This picture shows page 100, sub page 2. Notice the teletext block graphics are not supported in the tree view (left side). Every visible line can be expanded to see the actual data.

Apart from the normal visible lines this page has two other lines, line 26 is used for special characters (it puts the è in carrière on line 14), line 27 specifies the destinations for the colored buttons at the bottom of the page.

teletext sub titles

For teletext based subtitles all subtitles are shown in the order they were transmitted. So it is possible to browse through the history of sub titles. This can be usefull to compare them with DVB based titles.

VPS / WSS

This sample from the german DVB-T service of ARD shows a separate PID, which contains both VPS and WSS information.

DVB Subtitles

This segment has the same structure as that of teletext/EBU data. First there is a section showing the PES-packets (the "RAW"-data). When a PES packet contains enough information for a complete Display Set a preview of the title will be shown on the right. The seconds section "Titles" shows complete "Display Sets", even when they span multiple PES-packets. Also for Display Sets of type "page update" it will show the complete title, also using segments defined in earlier Display Sets. (This mechanism is often used for subtitling live programs, where separate words are sent as an update to the title already on display.)

This picture shows a segment of a DVB subtitling stream of ZDF. Expanded is the section which defines the color pallette to be used for subtitling. On the right a preview of what the selected title looks like. The background picture here is just a place holder, not part of the actual video. It is there to give an impression of the readability and transparancy of the title.

MPEG2 Video background

When possible DVB Inspector will try to show the actual video image as background for the title. For this the following conditions have to be statisfied;

• The titles are part of a service with MPEG2 Video
• The MPEG2 video is available (not encrypted)
• The stream with the MPEG2 video has previously been parsed

When all these conditions have been met DVB Inspector will for each title find the closest I-Frame (based on the PTS).

This page was last modified on 28/04/2013