The Class-A DVD Format Verification Laboratories are conducting market inspection for certain product categories of certain geographical areas in the world. Regretful to say, all inspection result except for audio disc inspection in Japan in 2000 was some errors. You can find description of errors and their frequency in followings. For more information, please consult with DVD Format/Logo Licensing Corporation (Fax:+81-3-5777-2884) for the appropriate Class-A Laboratory.

(Newly uploaded in Sep., 2001)

Table of Contents

[0] Video Disc Error Summary

[1] China Video Disc Market Inspection in 2000

[2] USA Video Disc Market Inspection in 2000 (1)

[3] USA Video Disc Market Inspection in 2000 (2)

[4] China Video Player Market Inspection in 2001

[1] China Video Disc Market Inspection in 2000

DVD Format Verification Laboratories conducted Market Inspection for the purpose of checking the quality of DVD Video Discs in the China market. As a result, it turned out as a surprising fact that all the discs inspected were non-compliant with the Specifications.

This report describes an outline of the Market Inspection and main items non-compliant with the Specifications. It is eagerly desired for DVD-Video Disc Manufacturers to utilise this report to secure the good quality of DVD-Video Discs.

Also, the problems of discs found through this inspection are to be reported from DVD Format/Logo Licensing Corporation to each DVD-Video Disc Manufacturer in question, requiring their own investigation and solution of the problems.  

1. Outline of Market Inspection
   
   
   1. Target region: China
   2. Target sample: DVD-Video Disc
   3. Number of Sample: 29 titles
   4. Testing method
      1. Physical test: Physical parameters were measured in accordance with DVD-Video Disc Test Specification Version 1.0, Form 4E, 5E, 6E, 7E & 8E.
      2. File Format was verified by using File System Verifier, DVD-FV10AV, provided by Matsushita Lab.
      3. Video Format was verified by using Video Verifier, DVD-NF02VE, provided by Matsushita Lab.
      4. Playback test: Discs were played back by following DVD-Video Players.
      5. PC Drive: Samsung SD612B/ SM304B, Creative DVD-6240E, Hitachi GD5000, Pioneer DVD-114LG, Ricoh MP9060A, Panasonic SR-8585, LG DRD-8080B "Soft Peg Player"????
         PC DVD Soft Peg Player: Cyber Link Power DVD Version 2.55, Inter Video Win DVD Version 2.1, Zoran Version 3.21.5.03, Mediamatics DVD Express Version 5.0, ATI DVD Player Version 1.2, Inter Actual PC Friendly, Real Magic Version 1.8.1, Q.I Cine Master Version C-3.0, Creative PC-DVD Encore Version 4.00 DVD-Video Player: Panasonic DVD-A120, Philips DVD955, LG DVD-3030, Pioneer DV-626D, Samsung DVD811
         Sampling: Random sampling at the market place of Shanghai & Beijing.
         
         
2. Test Summary
   
   The figure below indicates the number of discs which showed NGs through each test. Regarding Physical Format, 27 out of 29 discs were non-compliant with the Specifications. As to File Format, all the discs were non-compliant with the Specifications, and Application Format, 18 discs. As to playback, problems were found in 14 discs when played back with a hardware device; this does not mean, however, that all the devices used for the playback test showed a problem, and in fact, there was some hardware that could play back discs without any problems shown. In other words, only conducting the playback test is not enough to specify whether a disc has a problem. That is to say, whether a disc is problematic or not should be judged through Physical, File System, and Application tests.

   

3. Physical test
   
   The chart below is a list of the non-compliant items at the Physical test, in order of quantity. For Birefringence, 15 out of 29 discs were non-compliant with the Specification. In addition, more than 1/3 of all discs showed non-compliance in critical parameters, such as Angular deviation, Vertical deviation, Jitter, and the like.

   

4. Logical test
   
   The chart below shows the result of Logical test. The most frequent case of non-compliance is the wrong Logical Sector Number (LSN) in Anchor Volume descriptor pointer, Main Volume descriptor sequence and Reserve Volume descriptor sequence, which is stipulated in section 2.1 of File System Specifications. 19 out of 29 discs showed this type of problem. The second most frequent case is that Contents of Video Objectives (VOB), which is stipulated in section 5.1 of Video Specifications, is not compliant with the Specifications, concerning which 10 out of 29 discs were non-compliant.
   
   
   ("ROM101 2" means "DVD Specifications for Read-Only Disc Part 2 Version 1.01".)
   
   
5. Conclusion

[2] USA Video Disc Market Inspection in 2000 (1)

Error Report, Summary (Logical)

1. Following errors were found at inspection of 9 titles.

1.1 File System

Discrepancy in ISO/UDF : 1 title fails

Error:
In ISO and UDF files, the length of the file starting the same start address is different from each other.

Correction:
The same length should be defined in both UDF and ISO for the file starting the same address.

1.2 Wrong Character String : 3 titles fail

Error:
Un-defined small characters are used in

Directory Identifier of L Path Table Record

Directory Identifier of M Path Table Record, and

File Identifier.

Correction:
The top two should be in d-character or 00h, and the bottom one should be in d-character or either of "SEPARATOR1", "SEPARATOR2", "00h" or "01h". None of them allows to use the small characters.

1.3 Too Long File Identifier : 1 title fails

Error:
It exceeds 30 bytes.

Correction:
It should be no more than 30 bytes.

1.4 Wrong File Name ordering : 1 title fails

File Name in File Identifier of Directory does not array in the ascending order.

Correction:
Array them in the ascending order.

1.5 Extended Attribute Header Descriptor Error : 7 titles fail

Error:
In Extended Attribute Header Descriptor in File Entry, Application Attribute Location is set to the last byte of Extended Attribute.

Correction:
It should be the next byte to the last byte of Extended Attribute.

1.6 Directory Record inconsistency : 1 title fails

Error:
In the two Directory Records, Location of Extent is set to the same LBN but Data Length is different from each other.

Correction:
Keep Consistency.

1.7 Too deep Directory Hierarchy : 1 title fails

Error:
Directory Hierarchy exceeds eight (8) levels.

Correction:
To be within eight.

1.8 Allocation Descriptor inconsistency : 1 title fails

Error:
In Allocation Descriptor of File Entry, Extent Position is set to the same LBN but Extent Length is different.

Correction:
Keep consistency.

1.9 Non-Zero Padding : 3 titles fail

Error:
Non-Zero data are available in the padding field of File Identifier Descriptor.

Correction:
Should be 00h.

1.10 Wrong dstring length : 2 titles fail

Error:
The length of dstring in File Set Identifier is wrong.

Correction:
Set the correct figure.

1.11 Wrong File Link Count ; 3 titles fail

Error:
Wring File Link Count is set in File Entry.

Correction:
Set it correctly.

1.12 Wrong Descriptor CRC : 1 title fails

Error:
Descriptor CRC in Descriptor Tag is in error.

Correction:
Put the correct CRC.

2. Information

2.1 Wrong MAP_EN_Ns : 5 titles fail

Error:
For the PGC of less than 15 frames (one second), MAP_EN_Ns is set to "1".

Correction:
It should be "0".

2.2 Wrong Address in MAP_EN : 4 titles fail

Error:
The address in MAP_EN does not point to the top of VOBU which contains the video-frame to be presented at the time of TMU x N.

Correction:
Point it correctly.

2.3 Wrong Availability flag setting : 3 titles fail

Error:
Although PGC_AST_CTL and/or PGC_SPST_CTL set the availability flag to 1b, no corresponding Audio Stream and/or Subpicture is available.

Correction:
Set it to 0b.

2.4 Wrong Display mode : 2 titles fail

Error:
Display mode in Information does not match with Horizontal Size, Display Horizontal Size and Aspect Ratio in Elementary Stream.

Correction:
Set correctly as per the following definitions:

2.5 Audio Stream, Number of Channels inconsistency : 3 titles fail

Error:
Although the attribute of Elementary Stream is 2/0ch, but VTS_AST_ATR is set to "0".

Correction:
Keep consistency.

2.6 Wrong Structure IDCD : 2 titles fail

Error:
Regardless Title is available, IT_TXT_SRP_SA_TT is set to 0000h.

Correction:
In case, Structure_IDCS for Title should be TXTDT.

2.7 Wrong usage of SetTmpPML : 1 title fails

Error:
Although PTL_MAIT in VMGM is not available, Post Command of PGC in VMGM sets SetTmpPML.

Correction:
Do not use SetTmpPML in case.

2.8 Wrong C_PBTM : 1 title fails

Error:
C_PBTM is incorrect, so that it is discrepant from the real presentation time period of VOB/Cell.

Correction:
Correctly set it.

2.9 PTT_Ns inconsistent : 1 title fails

Error:
Number of PTTs in VMGI is different from the one in the corresponding VTS_PTT_SRPT.

Correction:
Keep it consistent.

3. VOB

3.1 MPEG Video Elementary Stream Error : 1 title fails

Error:
720x480 picture should have the 45 (=720/16) of macroblocks.

However, the slice carries more than 45.

3.2 Wrong PTS : 1 title fails

Error:
Audio Packet PTS just after Audio Gap is wrongly set.

3.3 Wrong HLI_E_PTM : 2 titles fail

Error:
It does not match the presentation end time of the corresponding SPU.

3.4 Wrong SP_SYNCA : 1 title fails

Error:
RLBN from the corresponding Navipack to the one for VOBU containing the target SP_Pack is not correctly set.

3.5 Wrong A_SYNCA : 1 title fails

Error:
RLBN from the Navipack containing the DSI to the target Audio_Pack is not correctly set.

3.6 Wrong PTM : 1 title fails

Error:
In the Interleaved Blocks in a VTS, the last PTM of the last SPU exceeds SCR of the last Pack.

Correction:
The last PTM of the last SPU should be less than the time set with SCR of the last Pack.

3.7 Wrong PTM : 1 title fails

Error:
In the VOBs connected with E-STD, the last PTM of the last SPU in the preceding VOB exceeds SCR of the last pack.

Correction:
The last PTM of the last SPU should be less than the time set with SCR of the last Pack.

3.8 Too short VOBU presentation time : 1 title fails

Error:
The presentation time of the last VOBU in a Cell is less than 0.4 second.

Correction:
It should be in between 0.4 and 1.2 seconds.

3.9 Wrong FWDn : 1 title fails

The starting address of VOBU to be presented after 0.5 x n seconds.

3.10 Sub-picture is not completed within a Cell : 1 title fails

Error:
Sub Picture error at Seamless connection

Correction:
The followings should be satisfied:

a. at Cell-boundary, SPU should be cleared with STP_DSP command of DCSQ

b. in the succeeding cell, SPU should be up-dated with Cell presentation time.

3.11 Buffer Overflow : 1 title fails

Error:
In a Dolby Digital (AC3) audio, Buffer Overflow is caused.

3.12 Too large Vo : 1 title fails

Error:
Vo exceeds the Max-Vo.

3.13 Too large Jump Distance : 1 title fails

Error:
Jump Distance is 42,063 sectors.

Correction:
It should be no more than 20,000 consecutive sectors.

[3] USA Video Disc Market Inspection in 2000 (2)

1. Outline of Inspection

Number of Sample : 19 titles

Testing method :
File System Format was verified by File System Verifier TFSV02, provided by Toshiba Lab. Video Format was verified by DVD-Video Verifier DVD-NF02VE, provided by Matsushita Lab.

2. Error in File System Format

2.1 Wrong Character String : 5 titles fail

Lower case characters are used in

Directory Identifier of L Path Table Record
Directory Identifier of M Path Table Record, and
File Identifier.

If you want to use lower case characters in file/folder name, you shall define them under Supplemental Volume Descriptor, described in Annex A.12　(in Ver.1.00).

2.2 Second Anchor Point Location Error : 5 titles fail

Second Anchor Point is not located at the sector which End sector number of the Data Area (PH-69) designates.
End sector number of the Data Area seems to be rounded to a multiple of 32.

2.3 Extended Attribute Header Descriptor Error : 8 titles fail

Attributes_Location shall be less than 132
In case of "No other attribute", 131 shall be described in UDF1.02.
(In UDF1.50, 132 shall be described.)

2.4 Non-Zero Padding : 2 titles fail

Non-zero data in trailing field of fixed-length character fields.

3. Error in Video Format

3.1 Buffer Underflow : 5 titles fail

Buffer management is wrong
Four titles contain a part where sub-picture buffer underflows.
One title contains a part where video buffer underflows.

3.2 PTT_Ns inconsistent : 1 title fails.

PTT_Ns in VMGI.TT_SRPT isn’t equal to the number of PTTs in VTS_PTT_SRPT.

3.3 Wrong C_PBTM : 1 title fails.

Difference is about 10 seconds.

3.4 Reserved bits in UOP_CTL is not 0 : 1 title fails.

Reserved bit in VOBU_UOP_CTL in PCI_GI isn’t set to 0b.

3.5 Wrong HLI_E_PTM : 1 title fails.

When the corresponding SPU is the last SPU in the Cell, HLI_E_PTM shall be equal to the end time of the last VOBU in the Cell(VOBU_E_PTM), in case the SPU does not have STP_DSP Command.

3.6 Sub-picture is not completed within a Cell : 1 title fails.

The last PTM of SPU is wrong
It is out of range of Cell presentation.

3.7 Not identical audio in seamless multi-angle : 1 title fails.

Audio packets are not identical in seamless multi-angle.

[4] China Video Player Market Inspection in 2001

DVD Format Verification Laboratories conducted Market Inspection of 20 models of DVD-Video Player sold in China, in co-operation with Verification Communication Group (VCG). As a result, it turned out that 19 out of 20 models were not compliant with the Specifications. Moreover, 17 models turned out to be Region Free.

This report describes an outline of the Market Inspection and main items non-compliant with the Specifications. It is eagerly desired for DVD-Video Player manufacturers to utilise this report to secure the good quality of their products.

Also, the problems found through this inspection are to be reported from DVD Format/Logo Licensing Corporation to each DVD-Video Player manufacturer in question, requiring their own investigation and solution of the problems.  

1. Outline of market inspection
   
   Target region: China
   Target sample: DVD-Video Player
   Number of samples: 20 models
   
   Test method:
   
   DVD-Video player samples were tested in accordance with DVD-Video Player Test Specifications Version 1.0 (May 1999). Test discs described below were used.
   NTSC Test Stream Disc: TDL-0002, Toshiba
   Navigation Files Test Discs: DVD-NF002 and DVD-NF150, Matsushita
   PAL Test Stream Disc: LVP00.06, Philips
   PAL Multichannel Test Disc: LVP08.01, Philips
   
   Sampling:
   
   Top 20 best sellers in the market place
   
   
2. Test Summary
   
   The chart below shows the kinds of Test Discs vertically, and the numbers of products which passed or failed in the tests horizontally.
   
   It was 4 out of 20 models that failed in the tests with NTSC Test Stream Disc and Navigation Files Test Disc Vol.1. As to the test with Navigation Files Test Disc Vol.2, it was only 3 players that did not cause any problems. Surprisingly, it was only 1 model that showed no problem through all the tests.
   
   Furthermore, it was found that 17 out of 20 models were set so that they could play back Region#1 discs as well.  

   

3. Contents of problem
   
   The chart below indicates the number of non-compliant models. Test items are shown in the vertical axis. Taking an example of Form 5A/11 at the bottom, it shows that there were 14 out of 20 models that failed in the Test No. 11 of Form 5A in DVD-Video Player Test Specification Version 1.0. This test, Form 5A/11, is a test for Navigation Timer. The problems found in 14 out of 20 models through this test were: the playback got freezing; otherwise the playback did not stop despite that it was supposed to stop after 10 seconds; and so on.
   
   Form 7A/07and Form 6A/25 are tests for MPEG Multichannel Audio that Audio Streams recorded at variable bit rate are played back. Through these tests, there occurred problems such as playback failure, interruption of sound, freezing of playback, and so on.
   
   Form 5A/04 and Form 5A/05 are tests to play back a disc recorded with signals for invalidating the player’s operations such as Stop, Pause, Skip, Title Play, and so on. The players judged as NG could operate the functions such as Stop, Pause, Skip and Title Play despite the invalidating signals.

   

4. Conclusion
   
   Judging from these test results, it is supposed that the China market is in confusion due to the expected incompatibility between DVD discs and players; however, problems have not been revealed yet for the following reasons:
   
   - There are only a small number of DVD-Video Discs equipped with Navigation Timer.
   
   - There is no DVD-Video Disc recorded with MPEG Multichannel Audio Stream in the market.
   
   - Forward Scan or Skip of the picture for which those operations are prohibited (i.e. the picture for indicating Copyright or Warning) does not trouble users but DVD-Video Disc manufacturers.
   
   However, once DVD-Video Discs with high-level Navigation functions are released, the problems will become uncovered at one stroke. In fact, in the summer of 2000, there occurred a problem in the U.S. and Europe that a certain best-seller model could not play back a killer title, several million of which had been already sold. Urgent measures by DVD-Video Player manufacturers are requested now.  

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