Private:mtv issues - Revision history

Gal3 at 19:09, 15 July 2010

2010-07-15T19:09:38Z

Gal3 at 21:40, 13 July 2010

2010-07-13T21:40:32Z

Gal3 at 21:38, 13 July 2010

2010-07-13T21:38:55Z

Gal3 at 19:23, 13 July 2010

2010-07-13T19:23:44Z

Gal3 at 19:22, 13 July 2010

2010-07-13T19:22:36Z

Gal3 at 22:49, 9 July 2010

2010-07-09T22:49:23Z

Gal3 at 22:45, 9 July 2010

2010-07-09T22:45:41Z

Gal3 at 22:44, 9 July 2010

2010-07-09T22:44:41Z

Gal3 at 22:30, 9 July 2010

2010-07-09T22:30:54Z

Gal3 at 22:30, 9 July 2010

2010-07-09T22:30:45Z

@@ Line 1: / Line 1: @@
 == MPE, and MPE-FEC sections are not being picked up by dvbSAM ==
 '''The Bug: '''
@@ Line 26: / Line 29: @@
 '''EDIT:'''*Analyzed Burst::enc_ts(), all ts sections '''DOES NOT''' seem logically generated
 *Created file containing hex dump of the burst being passed to Transmitter using Burst::dump_ts(). I viewed the TS file using dvbSAM to pick out missing sections in the burst. Then I looked into the hex dump for the TS packets containing the MPE/MPE-FEC section preceding the missing section, the missing section, and the section proceeding the missing section. All sections were found in the hex dump. '''The TS header seemed incorrect; some had 4 bytes, but should have 5.'''

@@ Line 25: / Line 25: @@
 *Analyzed Burst::enc_mpe_fec(), all mpe-fec sections seem logically generated
 '''EDIT:'''*Analyzed Burst::enc_ts(), all ts sections '''DOES NOT''' seem logically generated
-*Created file containing hex dump of the burst being passed to Transmitter using Burst::dump_ts(). I viewed the TS file using dvbSAM to pick out missing sections in the burst. Then I looked into the hex dump for the TS packets containing the MPE/MPE-FEC section preceding the missing section, the missing section, and the section proceeding the missing section. All sections where found in the hex dump. There was nothing unusual with the TS packets for the missing section.
+*Created file containing hex dump of the burst being passed to Transmitter using Burst::dump_ts(). I viewed the TS file using dvbSAM to pick out missing sections in the burst. Then I looked into the hex dump for the TS packets containing the MPE/MPE-FEC section preceding the missing section, the missing section, and the section proceeding the missing section. All sections were found in the hex dump. '''The TS header seemed incorrect; some had 4 bytes, but should have 5.'''
 '''Current Status:'''
 *Bug remains unsolved.
 *However, the good part is that MPE-FEC corrects these missing bytes of data.

@@ Line 17: / Line 17: @@
 '''Theory of why this is happening: '''
-*There is some semantic error in the code, possibly very small. I believe it is linked to some timing issue in the code. Perhaps the TS packets are not being received at the right time.
+*There is some semantic error in the code, possibly very small.
 *I believe that dvbSAM is throwing out some TS packets which happen to include the MPE/MPE-FEC header information which causes the entire section of data to be discarded.
 *The fact that there are some bursts which are perfect suggests that all the MPE and MPE-FEC sections are being generated correctly. And this in turn would also suggest that packing MPE, MPE-FEC, and TS packets are done correctly.
@@ Line 24: / Line 24: @@
 *Analyzed Burst::enc_mpe(), all mpe sections seem logically generated
 *Analyzed Burst::enc_mpe_fec(), all mpe-fec sections seem logically generated
-*Analyzed Burst::enc_ts(), all ts sections seem logically generated
+'''EDIT:'''*Analyzed Burst::enc_ts(), all ts sections '''DOES NOT''' seem logically generated
 *Created file containing hex dump of the burst being passed to Transmitter using Burst::dump_ts(). I viewed the TS file using dvbSAM to pick out missing sections in the burst. Then I looked into the hex dump for the TS packets containing the MPE/MPE-FEC section preceding the missing section, the missing section, and the section proceeding the missing section. All sections where found in the hex dump. There was nothing unusual with the TS packets for the missing section.

@@ Line 17: / Line 17: @@
 '''Theory of why this is happening: '''
-*There is some semantic error in the code, possibly very small. I believe it is link to some timing issue in the code.
+*There is some semantic error in the code, possibly very small. I believe it is linked to some timing issue in the code. Perhaps the TS packets are not being received at the right time.
 *I believe that dvbSAM is throwing out some TS packets which happen to include the MPE/MPE-FEC header information which causes the entire section of data to be discarded.
 *The fact that there are some bursts which are perfect suggests that all the MPE and MPE-FEC sections are being generated correctly. And this in turn would also suggest that packing MPE, MPE-FEC, and TS packets are done correctly.

@@ Line 17: / Line 17: @@
 '''Theory of why this is happening: '''
-*There is some semantic error in the code, possibly very small.
+*There is some semantic error in the code, possibly very small. I believe it is link to some timing issue in the code.
 *I believe that dvbSAM is throwing out some TS packets which happen to include the MPE/MPE-FEC header information which causes the entire section of data to be discarded.
 *The fact that there are some bursts which are perfect suggests that all the MPE and MPE-FEC sections are being generated correctly. And this in turn would also suggest that packing MPE, MPE-FEC, and TS packets are done correctly.

@@ Line 6: / Line 6: @@
 *The MPE and/or MPE-FEC sections missing also seem to be randomly determined.
 *Unfortunately a different TS file gets generated even if you run the program with the same configurations. This means that dvbSAM shows different #of packets per burst, different #of bytes corrected by MPE-FEC, etc. I produced at least 5 different TS files using the same configurations, none of which contained identical burst sequences.
+Perfect burst:
 [[{{ns:image}}:GoodFecAnalysis.png|685px]]
 [[{{ns:image}}:BadFecAnalysis.png|685px]]
 '''Theory of why this is happening: '''

← Older revision		Revision as of 22:45, 9 July 2010
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	[[{{ns:image}}:GoodFecAnalysis.png\|685px]]		[[{{ns:image}}:GoodFecAnalysis.png\|685px]]
		+	[[{{ns:image}}:BadFecAnalysis.png\|685px]]

	'''Theory of why this is happening: '''		'''Theory of why this is happening: '''

@@ Line 2: / Line 2: @@
 '''The Bug: '''
-*When the program is run using the STAND algorithm and the TS file is generated, dvbSAM has determined that there are entire MPE and/or MPE-FEC sections missing inside some bursts. (Maybe some are half missing as well, but I have no verified this claim)
+*When the program is run using the STAND algorithm and the TS file is generated, dvbSAM has determined that there are entire MPE and/or MPE-FEC sections missing inside some bursts. (Maybe some are half missing as well, but I have not verified this claim)
 *There does not seem to be a pattern in determining which burst will be missing sections. Some bursts will be 100% complete whereas some bursts will be missing at least one section of data.
 *The MPE and/or MPE-FEC sections missing also seem to be randomly determined.