# Wav sink problem **URL:** \ **Category:** GNU Radio\ **Created:** [September 26, 2012, 10:52pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256 "2012-09-26T22:52:29Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![aris](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/258eb7/32.png) [@aris](https://www.ruby-forum.com/u/aris)\ **Post date:** [September 26, 2012, 10:52pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/1 "2012-09-26T22:52:29Z")
Hi, i construct very simple scheme Audio Source --\> Wav Sink gr generates non-null wav file -rw-rw-r-- 1 anton anton 24M . 27 00:46 freq2.wav but when i try to play it or fetch info about file with soxi (sox plugin) i got nothing aplay freq2.wav WAVE ‘freq2.wav’ : Signed 16 bit Little Endian, 44100 , and soxi freq2.wav shows $ soxi freq2.wav Input File : ‘freq2.wav’ Channels : 1 Sample Rate : 44100 Precision : 16-bit Sample Encoding: 16-bit Signed Integer PCM so it seems to me wav sink produces corrupted wav files or … what am i doing wrong? e.g. soxi info on good wav file $ soxi arecord.wav Input File : ‘arecord.wav’ Channels : 1 Sample Rate : 8000 Precision : 8-bit Duration : 00:00:02.38 = 19000 samples ~ 178.125 CDDA sectors File Size : 19.0k Bit Rate : 64.1k Sample Encoding: 8-bit Unsigned Integer PCM look at Sample Encoding - it is Signed for gnuradio and Unsigned for all others. ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 4:43pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/2 "2012-09-27T16:43:27Z")
Hi Anton, I’d rather look if your audio source is producing the correct samples. On Thu, Sep 27, 2012 at 12:51:20AM +0400, Anton K. wrote: > i construct very simple scheme Audio Source → Wav Sink > gr generates non-null wav file > -rw-rw-r-- 1 anton anton 24M сент. 27 00:46 freq2.wav Looks good. > $ soxi freq2.wav > > Input File : ‘freq2.wav’ > Channels : 1 > Sample Rate : 44100 > Precision : 16-bit > Sample Encoding: 16-bit Signed Integer PCM Looks good, too. > File Size : 19.0k > Bit Rate : 64.1k > Sample Encoding: 8-bit Unsigned Integer PCM > > look at Sample Encoding - it is Signed for gnuradio and Unsigned for all others. You’re comparing 16- with 8-Bit. They’re different. Check the WAV file with Audacity. You can also connect the WAV sink to a signal source for further tests. M – Karlsruhe Institute of Technology (KIT) Communications Engineering Lab (CEL) Dipl.-Ing. Martin B. Research Associate Kaiserstraße 12 Building 05.01 76131 Karlsruhe Phone: +49 721 608-43790 Fax: +49 721 608-46071 www.cel.kit.edu KIT – University of the State of Baden-Württemberg and National Laboratory of the Helmholtz Association ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 4:56pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/3 "2012-09-27T16:56:54Z")
Hi, Martin, thanks for reply. In Audacity i see only gray background and no signal. Actually i have started with nbfm reciever and tried to save audio in wav file. That i tried to redirect it to audio sink and audio was ok. Than i tried to use very simple scheme with audio source to wav sink and realize that wav file is broken. I do not think it is good when soxi not shoing time length for the file - that means file is broken. On Thu, Sep 27, 2012 at 6:42 PM, Martin B. (CEL) ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 5:09pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/4 "2012-09-27T17:09:10Z")
On Thu, Sep 27, 2012 at 06:55:08PM +0400, Anton K. wrote: > file - that means file is broken. > Are you making sure the flow graph is terminated correctly? If you > simply kill the flow graph, the WAV block has no chance to write a > correct file header. This happens in the block destructor, or when you > call close(). > If you can’t do that, you must use gr\_file\_sink. MB > > > -rw-rw-r-- 1 anton anton 24M сент. 27 00:46 freq2.wav > > > > > Precision : 8-bit > > > signal source for further tests. > > > Kaiserstraße 12 > > > > * * * > > > > Discuss-gnuradio mailing list > > [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > > [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) > > * * * > > Discuss-gnuradio mailing list > [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) – Karlsruhe Institute of Technology (KIT) Communications Engineering Lab (CEL) Dipl.-Ing. Martin B. Research Associate Kaiserstraße 12 Building 05.01 76131 Karlsruhe Phone: +49 721 608-43790 Fax: +49 721 608-46071 www.cel.kit.edu KIT – University of the State of Baden-Württemberg and National Laboratory of the Helmholtz Association ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 5:14pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/5 "2012-09-27T17:14:26Z")
Martin, actually no, i am not sure. i am just pushing stop button in gnuradio companion. from grc perspective view, what method is supposed to be used for graceful script termination? On Thu, Sep 27, 2012 at 7:07 PM, Martin B. (CEL) ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 5:18pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/6 "2012-09-27T17:18:31Z")
I recall running into this issue myself now, with multimode and simple\_fm\_rcv. What I do in those two apps is that when I turn “off” recording, I change the wavfile filename to /dev/null, which causes a formal cleanup-and-close of the previous file. On 27 Sep 2012 11:13, Anton K. wrote: > Martin, > actually no, i am not sure. > i am > just pushing stop button in gnuradio companion. > > from grc > perspective view, what method is supposed to be used for > graceful > script termination? ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 5:29pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/7 "2012-09-27T17:29:37Z")
So it can programmed with GRC, or i supposed to make some stuff in python script? ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 5:59pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/8 "2012-09-27T17:59:27Z")
Ok i see. And, if i want to run script from shell to record audio files and rotate them every hour, how to make start/stop recording procedure in this case? ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 5:32pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/9 "2012-09-27T17:32:33Z")
On 27 Sep 2012 11:28, Anton K. wrote: > So it can programmed > with GRC, or i supposed to make some stuff in > python script? > > On > Thu, Sep 27, 2012 at 7:17 PM, [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > I recall > > running into this issue myself now, with multimode and simple\_fm\_rcv. > > What I do in those two apps is that when I turn “off” recording, I > > change the wavfile filename to /dev/null, which causes a formal > > cleanup-and-close of the previous file. On 27 Sep 2012 11:13, Anton > > Komarov wrote: Martin, actually no, i am not sure. i am just pushing > > stop button in gnuradio companion. from grc perspective view, what > > method is supposed to be used for graceful script termination? O > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ Discuss-gnuradio mailing > > list [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [1] > > [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) [2] Use a conditional expression in the “filename” field of the wavefile sink, and then have a “checkbox” control to control recording. Make the expression conditional on the state of the checkbox, and if “recording” isn’t checked, make the file /dev/null, otherwise make it the file you want. Links: ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 9:12pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/10 "2012-09-27T21:12:18Z")
Ok, tried with selector and check box. I started script, check box appeared, i cheched it and recording to wav file started. Wait a bit and unchecked it, got file 2.7 Mbytes, not growing more, then stopped the script. FIle is corrupted. Here is links on my grc scheme - [http://db.tt/ACl4nLNy](http://db.tt/ACl4nLNy) and wav file i got - [http://db.tt/87PIVwCy](http://db.tt/87PIVwCy) Any help will be appreciated, i dont believe wav sink is so buggy… ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 6:05pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/11 "2012-09-27T18:05:53Z")
On 27 Sep 2012 11:58, Anton K. wrote: > Ok i see. > > And, > if i want to run script from shell to record audio files and > rotate > them every hour, how to make start/stop recording procedure in > this > case? > > On Thu, Sep 27, 2012 at 7:31 PM, [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > On 27 Sep 2012 11:28, Anton K. wrote: So it can programmed with > > GRC, or i supposed to make some stuff in python script? On Thu, Sep 27, > > 2012 at 7:17 PM, \<[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [1]\> wrote: I recall running into > > this issue myself now, with multimode and simple\_fm\_rcv. What I do in > > those two apps is that when I turn “off” recording, I change the wavfile > > filename to /dev/null, which causes a formal cleanup-and-close of the > > previous file. On 27 Sep 2012 11:13, Anton K. wrote: Martin, > > actually no, i am not sure. i am just pushing stop button in gnuradio > > companion. from grc perspective view, what method is supposed to be used > > for graceful script termination? O > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ Discuss-gnuradio mailing > > list [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [2] > > [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) [3] Use a > > conditional expression in the “filename” field of the wavefile sink, and > > then have a “checkbox” control to control recording. Make the expression > > conditional on the state of the checkbox, and if “recording” isn’t > > checked, make the file /dev/null, otherwise make it the file you want. > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ Discuss-gnuradio mailing > > list [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [4] > > [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) [5] You can use the XMLRPC server that GRC provides to change any flow-graph variables you want from outside. ## Links: [1] [mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [2] [mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [3] [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) [4] [mailto:removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) [5] [Discuss-gnuradio Info Page](https://lists.gnu.org/mailman/listinfo/discuss-gnuradio) ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 27, 2012, 11:48pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/12 "2012-09-27T23:48:17Z")
> Ok, tried with selector and check box. > I started script, check box appeared, i cheched it and recording to > wav file started. > Wait a bit and unchecked it, got file 2.7 Mbytes, not growing more, > then stopped the script. > FIle is corrupted. Looked at your flow-graph. You have to make the _filename_ on the WAV sink change depending on recording/not-recording. Just use a conditional expression as the filename parameter in the filename sink “myfile” if recording\_on else “/dev/null” – Marcus L. Principal Investigator Shirleys Bay Radio Astronomy Consortium > **[Live Draw HK Tercepat | Result HK | HK Pools | Live HK | HK Prize Hari Ini](https://www.sbrac.org/)** > > Temukan live draw hk tercepat melalui halaman hk pools yang resmi dan dapatkan result hk prize melalui live hk secara langsung di situs kami. ---
**Author:** ![antonk](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/a5b964/32.png) [@antonk](https://www.ruby-forum.com/u/antonk)\ **Post date:** [September 28, 2012, 6:55am UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/13 "2012-09-28T06:55:17Z")
ok! with conditional filename works like a charm! thank you very much! sorry that i did get for the first time 😉 ---
**Author:** ![jteez](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/3ec8ea/32.png) [@jteez](https://www.ruby-forum.com/u/jteez)\ **Post date:** [December 23, 2020, 5:30pm UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/14 "2020-12-23T17:30:59Z")
Hi, I know its an old thread but supper grateful for finding this and just wanted to add comments from my windows environment not sure why, but had a bit of a mare getting to it work especially around string vs. quotes vs nul value, etc. I created a ‘QT GUI Checkbox’ called recording\_on. I set the type to string. I set the default and false values to “C:\xxxx\rubbish.wav” (without the quotes and with a proper folder structure and the true value to “C:\xxxx\rf\_file.wav” (without the quotes and with a proper folder". Then just set the filename property in the “Wav File Sync” to “recording\_on” (without the quotes)… Thanks All! ---
**Author:** ![rubybaz](https://www.ruby-forum.com/user_avatar/www.ruby-forum.com/rubybaz/32/2747_2.png) [@rubybaz](https://www.ruby-forum.com/u/rubybaz)\ **Post date:** [May 16, 2021, 5:48am UTC](https://www.ruby-forum.com/t/wav-sink-problem/223256/15 "2021-05-16T05:48:07Z")
I recall running into this subject myself, with multimode and simple\_fm\_rcv. What I do in those two apps is that when I turn “off” recording, I changed the wav-file filename to /dev/null, which causes a formal cleanup-and-close of the previous file.