Paul,
This is indeen NI-USRP capture. So you think the Cfile that I've created
using gr_fileman and gr_mkheader isn't correct? I can see lots of good data
by loading the cfile in Gqrx. I think it's working, am I wrong?

Also I had another question, I converted my file to Wav file after
demodulation (GMSK).
Here is audio file loaded in Audacity: http://imgur.com/a/CllLI

I can't properly figure out what's symbol rate here, can't clearly
distinguish 0 and 1s to count, then diff the time and find out symbol rate.
I would really appreciate any help/hint/advise.

Thank you!

On Thu, Dec 1, 2016 at 4:16 PM, Garver, Paul W <garv...@gatech.edu> wrote:

> Cheers, and thanks for finding the error. Also, you should note that the
> USRP scales fc32 format to +\- 1, but the sc16 format is ADC levels.
> gr_fileman doesn't scale during the conversion, so .sc16 converted to .fc32
> will be scaled differently than straight out of the USRP.
>
> Paul Garver
>
>
> On Dec 1, 2016, at 2:08 PM, AndroidT Tester <itestandroid2...@gmail.com>
> wrote:
>
> Hello Paul,
>
> Indeed it's working now :) I successfully converted my 16-bit IQ sample
> file to a Cfile :) Thanks for all your help!!
>
> On Thu, Dec 1, 2016 at 4:04 PM, Garver, Paul W <garv...@gatech.edu> wrote:
>
>> I think you found an error in gr_mkheader! In truth, it isn’t
>> particularly well tested so I’m glad you are using it. I just pushed a
>> commit to fix this to github. git pull the changes, rebuild, and try again.
>> Let me know if it solves the issue for you.
>>
>> PWG
>>
>> On Dec 1, 2016, at 11:46 AM, AndroidT Tester <itestandroid2...@gmail.com>
>> wrote:
>>
>> Thank you once again Paul.
>>
>> ls -la
>> drwx------ 1 Username Username       4096 Dec  1 13:40 .
>> drwx------ 1 Username Username      12288 Nov 30 16:21 ..
>> -rwx------ 1 Username Username 7683964928 Nov 20 18:23 Sample-408MHz
>>
>> gr_mkheader -r 1.8e6 -t sc16 -f 408e6 -l 1920991232 Sample-408MHz
>>
>>
>> Now I have Sample-408MHz.hdr:
>> gr_read_file_metadata Sample-408MHz.hdr -D
>> HEADER 0
>> Version Number: 0
>> Sample Rate: 1800000.00 sps
>> Seconds: 0.000000
>> Item size: 4
>> Data Type: short (1)
>> .....
>> .....
>> ....
>>
>>
>> etc.
>>
>> Now when I do
>>
>> gr_fileman Sample-408MHz Sample.cfile -o fc32
>>
>> I get
>> sample_cnt_end=500000,final_index=1920991232
>> Empty Header, quitting.
>>
>>
>>
>>
>> On Thu, Dec 1, 2016 at 1:35 PM, Garver, Paul W <garv...@gatech.edu>
>> wrote:
>>
>>> It probably can’t find the header. The command
>>>
>>> # gr_mkheader -r 1.8e6 -t sc16 -f 408e6 -l 1920991232 Sample-408MHz
>>>
>>> should produce the file "Sample-408MHz.hdr"
>>>
>>> Check that the file Sample-408MHz.hdr is produced. You can read it with
>>>
>>> # gr_read_file_metadata Sample-408MHz.hdr -D
>>>
>>> Then,
>>>
>>> # gr_fileman Sample-408MHz Sample-408MHz.cfile -o fc32
>>>
>>> Sample-408MHz should be the raw data, and Sample-408MHz.hdr the metadata
>>> produced with gr_mkheader.  This should produce
>>> Sample-408MHz.cfile and Sample-408MHz.cfile.hdr.
>>>
>>> On your copied command it appears you didn’t add the -o fc32 to specify
>>> you want a file type conversion.
>>>
>>> PWG
>>>
>>>
>>>
>>>
>>> On Dec 1, 2016, at 11:20 AM, AndroidT Tester <itestandroid2...@gmail.com>
>>> wrote:
>>>
>>> Thank you Paul,
>>>
>>> I got this;
>>> sample_cnt_end=500000,final_index=1920991232
>>> Empty Header, quitting.
>>>
>>> I followed all your instructions and double checked all parameters. I
>>> did filesize / 4 for sample count.
>>> I did this first:
>>>
>>> gr_mkheader -r 1.8e6 -t sc16 -f 408e6 -l 1920991232 Sample-408MHz
>>>
>>>
>>> Then when I try to do:
>>>
>>> gr_fileman Sample-408MHz Sample.cfile
>>>
>>> I got the error above, what am I missing?
>>>
>>> On Thu, Dec 1, 2016 at 12:07 PM, Garver, Paul W <garv...@gatech.edu>
>>> wrote:
>>>
>>>> There are two different metadata types:
>>>> 1) Inline
>>>> 2) Detached
>>>>
>>>> Here, you are using the detached headers. With detached, the raw
>>>> samples are in a file, say myfile.sc16, and the metadata in
>>>> myfile.sc16.hdr. See [1] for more information on GNURadio metadata.
>>>> So suppose you have myfile.sc16 as your raw sample file. Then you
>>>> generate headers for it, since you didn’t record it with any. You also need
>>>> to give gr_mkheader -l num_samps so it knows how long the file is. For sc16
>>>> you just do file_size_bytes/4 to get # of samples in a file.
>>>>
>>>> # gr_mkheader -r 1.8e6 -t sc16 -f 408e6 myfile.sc16
>>>>
>>>> This generates the file: myfile.sc16.hdr containing the file type,
>>>> center frequency, sample rate, etc. This is simply my convention, but the
>>>> metadata is “linked” to the raw samples by the filename
>>>> raw data: myfile.sc16, where sc16 specifies the file format.
>>>> metadata: myfile.sc16.hdr
>>>>
>>>> Then, you can give this to gr_fileman to convert the type:
>>>>
>>>> # gr_fileman myfile.sc16 myfile.fc32 -o fc32
>>>>
>>>> gr_fileman looks for filename.hdr for the detached header info. So in
>>>> this case, it files myfile.sc16.hdr, and should happily convert for you.
>>>>
>>>> PWG
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> [1] http://gnuradio.org/doc/doxygen/page_metadata.html
>>>>
>>>> On Dec 1, 2016, at 9:45 AM, AndroidT Tester <itestandroid2...@gmail.com>
>>>> wrote:
>>>>
>>>> Thank you Paul, I never heard of gr-analysis before.
>>>> So I tried this:
>>>>
>>>> gr_mkheader -r 1.8e6 -t sc16 -f 408e6 myheader
>>>>
>>>> This only created myheader.hdr file. How can I link this to my actual
>>>> recording sample which is 16-bit IQ pair and then convert it to CFile?
>>>> Do I concatenate the files? put myheader.hdr at top of my recording?
>>>> Sorry again for these newbie questions
>>>>
>>>>
>>>>
>>>> On Thu, Dec 1, 2016 at 11:32 AM, Garver, Paul W <garv...@gatech.edu>
>>>> wrote:
>>>>
>>>>> Please copy the list next time so other folks can respond besides me.
>>>>>
>>>>> Just attach a file sink to the ishort to complex block. There’s also a
>>>>> command-line tool called gr_fileman in gr-analysis [1] which will do this,
>>>>> but the file needs headers. If you don’t have them, you can generate with
>>>>> gr_mkheader in gr-analysis.
>>>>>
>>>>> [1] https://github.com/garverp/gr-analysis
>>>>>
>>>>> Hope this helps,
>>>>> PWG
>>>>>
>>>>> On Dec 1, 2016, at 9:22 AM, AndroidT Tester <
>>>>> itestandroid2...@gmail.com> wrote:
>>>>>
>>>>> Now, how can I convert this to a CFILE format where I can play it in
>>>>> Gqrx? Thank you
>>>>>
>>>>> On Wed, Nov 30, 2016 at 11:34 AM, AndroidT Tester <
>>>>> itestandroid2...@gmail.com> wrote:
>>>>>
>>>>>> Thank you very much! It worked :)
>>>>>>
>>>>>> On Wed, Nov 30, 2016 at 11:04 AM, Garver, Paul W <garv...@gatech.edu>
>>>>>> wrote:
>>>>>>
>>>>>>> Use a file source block with “short” type into an “Ishort to
>>>>>>> Complex” block. The Ishort to Complex block will de-interleave the 
>>>>>>> shorts
>>>>>>> into complex samples.
>>>>>>>
>>>>>>> PWG
>>>>>>> > On Nov 30, 2016, at 8:55 AM, AndroidT Tester <
>>>>>>> itestandroid2...@gmail.com> wrote:
>>>>>>> >
>>>>>>> > Hey guys,
>>>>>>> >
>>>>>>> > I have a sample file with IQ pairs, each I and Q is 16-bits, I
>>>>>>> want to load this in GNURadio companion using File source sink, but I'm 
>>>>>>> not
>>>>>>> sure how can I specify 16-bit format for I and 16-bit for Q in Gnuradio
>>>>>>> companion and then connect it to lets say FFT or Waterfall widget. Can
>>>>>>> someone advise a bit?
>>>>>>> >
>>>>>>> > Thank you!
>>>>>>> > _______________________________________________
>>>>>>> > Discuss-gnuradio mailing list
>>>>>>> > Discuss-gnuradio@gnu.org
>>>>>>> > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>>
>>>
>>>
>>
>>
>
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