Format Verification News

Book Subscribers > Format Verification News

Verification News (No 10) Feb. 2000

TO: All NDA Contractors of DVD Specifications

Feb. 2000

Dear Sirs:

We are pleased to provide you with DVD Format Verification News No.10. We hope that these informations would contribute to the growth of DVD market.

Sincerely,

Class-A Verification Laboratories:

Tokyo (Hitachi) Laboratory
Fax:+81-3-3506-1603

Asia (ITRI) Laboratory
Fax: +886-3-5917531
+886-3-5832805

Tokyo (JVC) Laboratory
Fax:+81-45-450-1639

Osaka (Matsushita) Laboratory
Fax: +81-6-6909-5027

Tokyo (Pioneer) Laboratory
Fax: +81-42-990-2831

Europe (Philips) Laboratory
Fax: +31-40-2732113
http://www.licensing.philips.com

Tokyo (Sony) Laboratory
Fax: +81.3.5769.5890

North America (WAMO) Laboratory
Fax: +1-570-383-0328

Tokyo (Toshiba) Laboratory
Fax: +81-3-5444-9430

Table of Contents:
1. Introduction of Osaka (Matsushita) Laboratory
2. Information of DVD Video Player Playback Problem
3. Information of DVD Video Disc Problems
4. Information of DVD Video Book Interpretation

1. Introduction of Osaka (Matsushita) Laboratory

DVD Verification Laboratory

Matsushita Electric Industrial Co.,Ltd.

Supporting the DVD World

Vital roles of the DVD Verification Laboratory of Matsushita

The market of DVD products, which are developed and produced based upon DVD-ROM/Video Specifications issued in August of 1996, has been growing rapidly. It is now expected in the world that 1,000 or more DVD-Video players are needed in the 2000s. The Specifications for DVD products, such as DVD-RAM, DVD-R, DVD-Audio, DVD Video Recording and DVD-RW, have been settled and their products have come into the market. DVD Verification Laboratory of Matsushita was established as the one approved by DVD Forum in November of 1996. Since then, MEI’s Laboratory has been contributing to improvement of the reliability of DVD products, developing the tools for DVD Format Verification and offering the DVD related companies with Format Verification Services to keep the compatibility between DVD players and DVD discs properly in the market.

Theater

DVD Format Verification Activities

DVD Verification Laboratory does Format Verification to keep DVD products reliable in the market. Laboratory examines the sample which has been submitted by licensee. The sample which conforms to the DVD Specifications is recognized as DVD product, and allowed to indicate DVD Logo mark by Laboratory. Laboratory also gives licensee the advice about the product quality if necessary. Format Verification of the following DVD products is available in MEI’s Laboratory.


DVD-Video Disc Operational Signal measuring System	DVD-RAM Disc Evaluation System

DVD-Video Disc
DVD-Video Player
DVD-Audio Disc
DVD-Audio Player
DVD-RAM Disc
DVD-RAM Drive
PC DVD Player
DVD-ROM Drive
DVD H/W Decoder
DVD S/W Decoder
DVD-RAM Video Recorder: Available from 2Q/2000
DVD-R (4.7GB) Disc: Available from 2Q/2000
DVD-R (4.7GB) Drive: Available from 2Q/2000

Development & Delivery of DVD Verification Tools

Laboratory develops Format Verification Tools for DVD products on the strength of DVD Specifications and delivers them to the DVD related companies before the new products come into the market. The companies can bring the products compliant with DVD Specifications to the market using the DVD Verification Tools. MEI’s Laboratory offers the Verification Tools for Disc, such as Verifiers for the format of file and applications of DVD-Video, DVD-Audio, DVD-RAM and DVD-Video Recording. And MEI also offers the Verification Tools for Player and Drive, such as Test Discs of DVD-Video, DVD-Audio, DVD-RAM and DVD-Video Recording. You can get more information on this web site.


DVD-Video Test Disc	DVD-Audio Test Disc	DVD-RAM Test Disc

Consultation Activities

DVD Verification Laboratory judges whether or not the DVD products conform to DVD Specifications, and responses the inquiries about the interpretation of DVD Specifications so that DVD related companies can apply DVD Specifications properly. MEI’s Laboratory also offers the DVD manufacturers with the rental services so that they can verify their DVD products by themselves using the equipment in MEI’s Laboratory, such as the Disc Evaluation System and all that.

Market Inspection Activities

DVD Verification Laboratory attaches importance to the DVD products compatibility in the market, watching the DVD products compatibility and conformity to DVD Specifications in the market. Laboratory records the results of the Market Inspection and accumulates them to our data base. As for the significant information for the DVD related companies, Laboratory discloses it to the subscribers of DVD Book on the Format Verification News. You can see the Format Verification News on this web site.

DVD Verification Laboratory

Matsushita Electric Industrial Co., Ltd.
2-15, Matsuba-cho, Kadoma, Osaka 571-8503 Japan
Phone: +81-6-6905-4195/ Fax: +81-6-6909-5027

Contact Person:

Asaichi Akagi/ E-mail: akagi@dvd.mei.co.jp

Masatsugu Kimura/ E-mail: mkimura@dvd.mei.co.jp

2. Information of DVD Video Player Playback Problem

(1) ID No. :110080

< disc Configuration>
The disc contains an I or P picture which is ;
1. displayed at the end of a video stream
2. the last picture not only in display order but also in coding order
3. not followed by Sequence_end_code.

< phenomena of playback problems >
The last picture is not displayed.

< recommended disc configuration >
Put B picture last in coding order, or add Sequence_end_code last.

< related Information >
The recommendation of this information conflicts with ID No.107054 in Lab News No.7.
To avoid the both problems described in No.107054 and No.110080, add Sequence_end_code at the end of a video stream.

3. Information of DVD Video Disc Problems

(1) ID No.: 110081
Image problems due to different field picture types within a video frame

< description of Disc Problem>
Picture_header picture_coding_type of both field pictures are not the same within a video frame.

The matter of Picture_header picture_coding_type is described in the MPEG Spec as below.
Reference : MPEG2 Video 6.3.10 (just below table 6-14)

In researching the DVD specification it indicates that two pictures in a field pair must be of the same picture type except when the first field of the pair is an I picture. Then the next field can be an I or a P.

< phenomena of playback problems>
This problem results in no visible effects on certain DVD players, but on other DVD players clearly noticeable problems appear.
This only shows up in field mode encoding when we allow an I picture to be forced on a bottom field In a file-encoded movie the image flashes at fixed positions on only a certain brand of decoders. During playback you can see that from time to time the image goes back to a previously displayed image to 'reset' its decoding.

(2) ID No.: 110082
Wrongly displayed menus due to invalid aspect ratio indication.

< description of Disc Problem>
Illegal aspect ratio information in Sequence headers is used in the MPEG Video elementary stream.
This error occurs in the VOB files of menus (VMGM and VTSM). The error reports that a reserved value is used in the sequence header, for the aspect ratio of the menu data instead of 4 :3 or 16 :9.

Use correct values for the aspect ratio indication, 2 for 4:3 or 3 for 16:9.

< phenomena of playback problems>
This problem results in no visible effects on certain DVD players, but on other DVD players clearly noticeable problems appear.
The result of this error will be that on some players the menu will be shifted to the left. The cut off part on the left will than be added again on the right of the screen. All highlighting of the menu buttons isn't shifted and therefore buttons and highlighting don't match any longer

(3) ID No.: 110083
Player crash due to illegal JumpSS command

< description of Disc Problem>
JumpSS command specified an illegal VTSN in the VTS-Space (VTS Menu Domain) (ref. DVD-3 4.6.4.3)

In the VTSM domain, a JumpSS is only allowed within the VTS from where the Jump is issued. Therefore the VTSN should always have the value 0 (zero) when a JumpSS is performed in the VTS space.

< phenomena of playback problems> The result is that on some players, the program will crash at the moment you press this particular button, while other players handle this erroneous navigation command without any visible problem

(4) ID No.: 110084
Subtitle problems due to overlapping presentation periods.

< description of Disc Problem>
The SP_DCSQ_STM incremented with 1 video frame period is not equal to or smaller than the PTS of the next SPU !

Set the SP_DCSQ_STM to the correct values so that no overlapping occurs.

< phenomena of playback problems>
Severe sub-picture problems occurred in case the end time of one sub-picture unit was about 100 seconds later than start time of the sub-picture unit that follows. Sub-pictures appear at wrong times or no sub-pictures are displayed at all.

(5) ID No.: 110085
Distorted sub-pictures due to wrong amount of bits used.

< description of Disc Problem>
PXD run_length coded data in SP unit uses more bits than allowed.

When the run-length compression method is used for the sub-pictures, make sure the size of the run-length coded data within one line never exceeds 1440 bits.

< phenomena of playback problems>
Subtitle lines are shifted which will result in distorted sub-pictures.

(6) ID No.: 110086
Playback errors due to wrong start address

< description of Disc Problem>
Wrong cell start addresses indicated in the C_PBITs.

The start address of each cell indicated in the C_PBIT should correspond with the actual start address of the first VOBU in the cell.

< phenomena of playback problems>
The movie always starts at the very beginning when selecting any chapter entry.

(7) ID No.: 110087
No video playback due to SCR decrease

< description of Disc Problem>
The Pack_header SCR difference is -57266085 (-636.3 sec.) in VTS_01.

The time interval between 2 system clock references should always be positive, except for SCR reset in E-STD presentation.

< phenomena of playback problems>
On some DVD video players, the disc started but only the menu was accessible. On other players, the disc didn't start at all. The movie could never be played. On PC DVD video playback systems the disc functioned correct.

(8) ID No.: 110088
Navigation Arrangement when GPRMs initialized

< description of Disc Problem>
Navigation on Disc is designed without taking into consideration that GPRMs should be reset to ZEROs in the following case:

- At Initial Access
- When Title_Play(), PTT_Play() or Time_Play() is executed in all Domains and Stop State.
- When Menu_Call() is executed in Stop State.

< phenomena of playback problems>
Playback of players are not guaranteed when no instruction is set for GPRM=0; players may stop or behave differently from the intention of navigation design at the time.

For instance, the player does not display any MENU at the execution of Menu_Call() at Stop State:

FP_PGC forces to execute VMGM_PGCN#5 as Dummy PGC.
PRE_CMD in VMGM_PGCN#5 sets the value of SPRM#20==Player Region Code to GPRM#11.
On the other hand, Pre-Command of VTSM_PGCN#4 in VTSN#2 executes Compare and Link_Command with the GPRM#11, there is no destination for GPRM#11==0.

4. Information of DVD Video Book Interpretation

TG1-1 decided to announce the following sentence:
In System Space, the value of SPRM(4) is not defined after JumpSS is executed with Domain ID= * 10b *.

This issue will not be described in any Supplemental Information.

Explanation for Contents Providers: :
The value of SPRM(4) is not defined when it enters VTSM space with a JumpSS instruction. Therefore, it is desirable to assume that SPRM(4) is not defined in the System-Space when a JumpSS command with Domain ID= '10b' is used anywhere on the disc. :
Work around might include the use of SPRM(5) instead of SPRM(4) in appropriate cases.