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gnuradiotips [2021/09/13 22:26] – [Using Baseband I/Q Recordings] mm3iiggnuradiotips [2021/09/13 22:27] (current) – [Using Baseband I/Q Recordings] mm3iig
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 Depending on the specifics of your recording you may need to change bits of this. You’ll want to use a WAV file sync, set the channels to two, and then immediately convert from float to complex to do useful things with the data. Then you’ll want a throttle block to set your desired sample rate. If you have recordings in a format other than RIFF 16-bit stereo you may need to add extra conversion steps into your flowgraph, or convert your input file first with other software. Depending on the specifics of your recording you may need to change bits of this. You’ll want to use a WAV file sync, set the channels to two, and then immediately convert from float to complex to do useful things with the data. Then you’ll want a throttle block to set your desired sample rate. If you have recordings in a format other than RIFF 16-bit stereo you may need to add extra conversion steps into your flowgraph, or convert your input file first with other software.
  
-One thing you will have to look out for is the 4 GB wav file size limit in GNU Radio. WAV File Source blocks use the metadata of the file which can only store a maximum value of of 4 GB in its 32-bit size variable. Other apps can store more in a WAV container by reading file size information directly from the operating system.+One thing you will have to look out for is the 4 GB wav file size limit in GNU Radio. WAV File Source blocks use the metadata of the file which can only store a maximum value of of 4 GB in its 32-bit size variable. Other apps can store more in a WAV container by reading file size information directly via the operating system, and typically ignore any useful data in the headerApps that support this include SDR Console and SDR++
  
 To get around this you can use a tool such as sox to chop up your file into smaller chunks. You can estimate using different times and see if you get the chunk sizes you want - the following command will continue to make chunks of the chosen mm:ss length until there’s no more data and iterate a number after the outfile name: To get around this you can use a tool such as sox to chop up your file into smaller chunks. You can estimate using different times and see if you get the chunk sizes you want - the following command will continue to make chunks of the chosen mm:ss length until there’s no more data and iterate a number after the outfile name:
gnuradiotips.1631571980.txt.gz · Last modified: 2021/09/13 22:26 by mm3iig