AMR-WB Encoder Decoder Basic Doubt, modes does not give correct bitrates... |
AMR-WB Encoder Decoder Basic Doubt, modes does not give correct bitrates... |
May 8 2008, 08:16
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#1
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![]() Group: Members Posts: 71 Joined: 17-August 05 From: Bangalore Member No.: 23959 |
Hi,
I downloaded AMR-NB/WB code from ITU-T website for development. I compiled AMR-WB and tested with a 4 second speech stream @16KHz and 16bits/sample. Using mode0 i.e. 6.6kbps mode it gives me encoded file as ~53KB size BUT I expect an encoded size of (6.6kbps*4*1000/8) bytes i.e. 3300 Bytes or ~3.2 KB Again, input bitrate is 256kbps to the encoder and we are supposed to get 6.6kbps i.e. a compression gain ratio of ~38-39 but if we consider 53KB encoded stream as correct then the corresponding bitrate is ~108kbps which is a compression gain of 256/108 = 2.3 which seems to be very less for a speech encoder. this is happening with all the mdoes... I need to be clear on this to proceed further to development of the codecs. AMR-NB also has same problem... Please let me know the testing procedure and if I am missing out anything before I start. Thank you. |
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Feb 1 2009, 19:56
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#2
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Group: Members Posts: 99 Joined: 8-March 08 Member No.: 51874 |
Hi, I downloaded AMR-NB/WB code from ITU-T website for development. I compiled AMR-WB and tested with a 4 second speech stream @16KHz and 16bits/sample. Using mode0 i.e. 6.6kbps mode it gives me encoded file as ~53KB size BUT I expect an encoded size of (6.6kbps*4*1000/8) bytes i.e. 3300 Bytes or ~3.2 KB Again, input bitrate is 256kbps to the encoder and we are supposed to get 6.6kbps i.e. a compression gain ratio of ~38-39 but if we consider 53KB encoded stream as correct then the corresponding bitrate is ~108kbps which is a compression gain of 256/108 = 2.3 which seems to be very less for a speech encoder. this is happening with all the mdoes... I need to be clear on this to proceed further to development of the codecs. AMR-NB also has same problem... Please let me know the testing procedure and if I am missing out anything before I start. Thank you. try Voice Age: http://www.voiceage.com/freecodecs.php |
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audio_geek AMR-WB Encoder Decoder Basic Doubt May 8 2008, 08:16
neutronium The ITU-T code of G.722.2/AMR-WB uses the G.192 wa... Jan 28 2009, 13:14![]() ![]() |
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