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bensari / mediaserver

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Clicking during playback #87

Closed GoogleCodeExporter closed 8 years ago

GoogleCodeExporter commented 8 years ago 
When playing audio files I get clicking at the beginning of the audio file and 
at the start of the second audio file. Please see the pcap file attached for a 
sample conversation from a customer with this issue.

Original issue reported on code.google.com by quintana...@gmail.com on 22 Oct 2012 at 6:21

Attachments:

GoogleCodeExporter commented 8 years ago 
Please attach first and second audio files

Original comment by oifa.yul...@gmail.com on 22 Oct 2012 at 6:40

GoogleCodeExporter commented 8 years ago 
I have attached the two audio files.

Original comment by quintana...@gmail.com on 22 Oct 2012 at 7:39

Attachments:

GoogleCodeExporter commented 8 years ago 
Please take a look at : 
https://ccrma.stanford.edu/courses/422/projects/WaveFormat/
wav file format has 44 bytes header and then data chunk
this means that data in file should have fileLength-44 bytes
in your case its 17726-44=17682
and 65870-44=65826
for pcm codec frame length is 320 bytes
for a/u law its 160 bytes
therefore for both you dont have an integer number of frames in both files
which can lead to adding trailing junk in last frame of each file

Example of files stored by mms : 
-rw-r--r-- 1 root root    44 2012-10-09 16:18 
0af09760121c11e2ae28c46e53df2efe.w                                     av
-rw-r--r-- 1 root root 81324 2012-10-22 20:22 
630353d01c7511e29aabb66c8cd35abb.w                                     av
-rw-r--r-- 1 root root    44 2012-10-09 16:30 
c54a0410121d11e2a1b43fdb989df6fc.w                                     av

Two files are empty , one is 81324 in legth. 81324-44=81280
81280/320=254 complete frames

Therefore its a file problem

Original comment by oifa.yul...@gmail.com on 23 Oct 2012 at 8:34

GoogleCodeExporter commented 8 years ago 
As it appears while using alaw , ulaw files which have incomplete frames due to 
decoding techniques used padding instead of 0 becomes very high negative values 
which in turn causes clicking.
Need to add different padding depending on codec used in wav file

Original comment by oifa.yul...@gmail.com on 23 Oct 2012 at 4:05

GoogleCodeExporter commented 8 years ago 
Hi Yulian,

I apologize for the delay in the feedback. I took the actions that you and I 
discussed earlier today but the peak is still in the the stream. I have 
attached the file with changes so you can verify that I didn't misunderstand 
you and a tshark capture of the call. Please let me know if there is anything 
else I can do to help.

Best Regards,
Tom

Original comment by quintana...@gmail.com on 24 Oct 2012 at 2:47

Attachments:

GoogleCodeExporter commented 8 years ago 
[deleted comment]
GoogleCodeExporter commented 8 years ago 
1) Please verify that you are testing against correct version ( with updates )
2) Try this one

Original comment by oifa.yul...@gmail.com on 24 Oct 2012 at 7:55

Attachments:

GoogleCodeExporter commented 8 years ago 
Hi Yulian,

I re-compiled using the provided WavTrackImpl.java and when I run the tests the 
peak is still present. I have attached the capture file.

Best Regards,
Tom

Original comment by quintana...@gmail.com on 24 Oct 2012 at 2:39

Attachments:

GoogleCodeExporter commented 8 years ago 
Hi Yulian,

The time of dip between the old capture and the new capture is significantly 
smaller. I have taken screenshots of the sine waves where you can also find the 
timing on the top ruler (time is measured in seconds, the old capture has a 
10ms dip the new capture has much less but still perceivable). Also, it seems 
there is a dip in the beginning, in the picture titled captures-front-dip.png I 
have zoomed in to the sine wave so you can see the dip. I have attached all the 
relevant files. I hope this helps.

Best Regards,
Tom

Original comment by quintana...@gmail.com on 25 Oct 2012 at 12:04

Attachments:

GoogleCodeExporter commented 8 years ago 
Ok lets summarize 
Indeed the problem occured due to 2 problems
1) Padding was invalid in case of G711 
2) There may be additional bytes in header for any other coded then pcm.

Please confirm that currently it works.

Original comment by oifa.yul...@gmail.com on 25 Oct 2012 at 9:50

Attachments:

GoogleCodeExporter commented 8 years ago 
Please check PCM , ALAW and ULAW file formats , 10x

Original comment by oifa.yul...@gmail.com on 25 Oct 2012 at 9:51

GoogleCodeExporter commented 8 years ago 
Hi Yulian,

I have attached the pictures with the results. It seems the only thing left is 
the dip at the beginning of each file.

Best Regards,
Tom

Original comment by quintana...@gmail.com on 25 Oct 2012 at 2:32

Attachments:

GoogleCodeExporter commented 8 years ago 
Hi Yulian,

After the suggested fixes everything is working perfect for wav files 
containing alaw, ulaw, and PCM. I have attached all the relevant files.

Best Regards,
Tom

Original comment by quintana...@gmail.com on 26 Oct 2012 at 2:05

Attachments:

GoogleCodeExporter commented 8 years ago 
Modified by revision  cd6f061a87a7
Waiting for mss team approval

Original comment by oifa.yul...@gmail.com on 27 Oct 2012 at 7:26

GoogleCodeExporter commented 8 years ago

Original comment by oifa.yul...@gmail.com on 27 Oct 2012 at 10:04

GoogleCodeExporter commented 8 years ago 
Closed

Original comment by oifa.yul...@gmail.com on 29 Oct 2012 at 2:14