Added CVSD encoder/decoder to GRC, example app
authorJohnathan Corgan <jcorgan@corganenterprises.com>
Sun, 20 Sep 2009 03:38:24 +0000 (20:38 -0700)
committerJohnathan Corgan <jcorgan@corganenterprises.com>
Sun, 20 Sep 2009 03:38:24 +0000 (20:38 -0700)
Used blks2.cvsd* wrappers, not bare gnuradio.vocoder.cvsd*
Example application sweeps 0-4KHz through encoder/decoder pair configured
as Bluetooth standard

grc/blocks/Makefile.am
grc/blocks/blks2_cvsd_decode.xml [new file with mode: 0644]
grc/blocks/blks2_cvsd_encode.xml [new file with mode: 0644]
grc/blocks/block_tree.xml
grc/examples/Makefile.am
grc/examples/audio/cvsd_sweep.grc [new file with mode: 0644]

index 32ddc6567f3bbc6fbf4559262edd5e1c579b173b..617a3bf6085bd50f2f1b577d1c7fc404dd1fbe2d 100644 (file)
@@ -30,6 +30,8 @@ dist_ourdata_DATA = \
        band_reject_filter.xml \
        blks2_am_demod_cf.xml \
        blks2_analysis_filterbank.xml \
+       blks2_cvsd_encode.xml \
+       blks2_cvsd_decode.xml \
        blks2_dxpsk_demod.xml \
        blks2_dxpsk_mod.xml \
        blks2_error_rate.xml \
diff --git a/grc/blocks/blks2_cvsd_decode.xml b/grc/blocks/blks2_cvsd_decode.xml
new file mode 100644 (file)
index 0000000..6be7daa
--- /dev/null
@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+## CVSD Encoder
+###################################################
+ -->
+<block>
+       <name>CVSD Decoder</name>
+       <key>blks2_cvsd_decode</key>
+       <import>from gnuradio import blks2</import>
+       <make>blks2.cvsd_decode($resample,$bw)</make>
+       <param>
+         <name>Resample</name>
+         <key>resample</key>
+         <value>8</value>
+         <type>int</type>
+       </param>
+       <param>
+         <name>Frac. Bandwidth</name>
+         <key>bw</key>
+         <value>0.5</value>
+         <type>real</type>
+       </param>
+       <sink>
+               <name>in</name>
+               <type>byte</type>
+       </sink>
+       <source>
+               <name>out</name>
+               <type>float</type>
+       </source>
+</block>
diff --git a/grc/blocks/blks2_cvsd_encode.xml b/grc/blocks/blks2_cvsd_encode.xml
new file mode 100644 (file)
index 0000000..3123b1a
--- /dev/null
@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+## CVSD Encoder
+###################################################
+ -->
+<block>
+       <name>CVSD Encoder</name>
+       <key>blks2_cvsd_encode</key>
+       <import>from gnuradio import blks2</import>
+       <make>blks2.cvsd_encode($resample,$bw)</make>
+       <param>
+         <name>Resample</name>
+         <key>resample</key>
+         <value>8</value>
+         <type>int</type>
+       </param>
+       <param>
+         <name>Frac. Bandwidth</name>
+         <key>bw</key>
+         <value>0.5</value>
+         <type>real</type>
+       </param>
+       <sink>
+               <name>in</name>
+               <type>float</type>
+       </sink>
+       <source>
+               <name>out</name>
+               <type>byte</type>
+       </source>
+</block>
index 5a989cc018d6ba211360d693bac0711ae6d127d6..296f0ee911b505298cc893675656aa1cd88f74e1 100644 (file)
                <block>gr_scrambler_bb</block>
                <block>gr_descrambler_bb</block>
        </cat>
+       <cat>
+               <name>Vocoders</name>
+               <block>blks2_cvsd_encode</block>
+               <block>blks2_cvsd_decode</block>
+       </cat>
        <cat>
                <name>Probes</name>
                <block>gr_probe_avg_mag_sqrd_x</block>
index 969485c0d5fa22c2c8934fdfca6ee50767bdee4a..78321ce0a8db288208c6dcee51335670dedf5963 100644 (file)
@@ -25,7 +25,8 @@ grc_examples_prefix = $(exampledir)/grc
 
 audiodatadir = $(grc_examples_prefix)/audio
 dist_audiodata_DATA = \
-       audio/dial_tone.grc
+       audio/dial_tone.grc \
+       audio/cvsd_sweep.grc
 
 simpledatadir = $(grc_examples_prefix)/simple
 dist_simpledata_DATA = \
diff --git a/grc/examples/audio/cvsd_sweep.grc b/grc/examples/audio/cvsd_sweep.grc
new file mode 100644 (file)
index 0000000..8d0b385
--- /dev/null
@@ -0,0 +1,918 @@
+<?xml version='1.0' encoding='ASCII'?>
+<flow_graph>
+  <timestamp>Sat Sep 19 20:30:08 2009</timestamp>
+  <block>
+    <key>import</key>
+    <param>
+      <key>id</key>
+      <value>import_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>import</key>
+      <value>import math</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(157, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>blks2_cvsd_decode</key>
+    <param>
+      <key>id</key>
+      <value>blks2_cvsd_decode_0</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>resample</key>
+      <value>resample</value>
+    </param>
+    <param>
+      <key>bw</key>
+      <value>bw</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(887, 340)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_sig_source_x</key>
+    <param>
+      <key>id</key>
+      <value>tri_source</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>waveform</key>
+      <value>gr.GR_TRI_WAVE</value>
+    </param>
+    <param>
+      <key>freq</key>
+      <value>0.05</value>
+    </param>
+    <param>
+      <key>amp</key>
+      <value>0.5</value>
+    </param>
+    <param>
+      <key>offset</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(44, 316)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_throttle</key>
+    <param>
+      <key>id</key>
+      <value>throttle</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>samples_per_second</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>vlen</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(238, 348)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_vco_f</key>
+    <param>
+      <key>id</key>
+      <value>vco</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>sensitivity</key>
+      <value>audio_rate*2*math.pi</value>
+    </param>
+    <param>
+      <key>amplitude</key>
+      <value>0.9</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(427, 332)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>blks2_cvsd_encode</key>
+    <param>
+      <key>id</key>
+      <value>enc</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>resample</key>
+      <value>resample</value>
+    </param>
+    <param>
+      <key>bw</key>
+      <value>bw</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(655, 340)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_packed_to_unpacked_xx</key>
+    <param>
+      <key>id</key>
+      <value>p2u</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>byte</value>
+    </param>
+    <param>
+      <key>bits_per_chunk</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>endianness</key>
+      <value>gr.GR_MSB_FIRST</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(648, 415)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>180</value>
+    </param>
+  </block>
+  <block>
+    <key>gr_char_to_float</key>
+    <param>
+      <key>id</key>
+      <value>c2f</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(676, 483)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>audio_sink</key>
+    <param>
+      <key>id</key>
+      <value>audio_sink</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>device_name</key>
+      <value>plughw:0,0</value>
+    </param>
+    <param>
+      <key>ok_to_block</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(1127, 340)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>8000</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(251, 10)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>resample</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>8</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(344, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>variable</key>
+    <param>
+      <key>id</key>
+      <value>bw</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>value</key>
+      <value>0.5</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(431, 11)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>notebook</key>
+    <param>
+      <key>id</key>
+      <value>displays</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>style</key>
+      <value>wx.NB_TOP</value>
+    </param>
+    <param>
+      <key>labels</key>
+      <value>['Original','Encoded','Decoded']</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value></value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(12, 106)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_fftsink2</key>
+    <param>
+      <key>id</key>
+      <value>orig_fft</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Original Spectrum</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>baseband_freq</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>y_per_div</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>y_divs</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>ref_scale</key>
+      <value>2.0</value>
+    </param>
+    <param>
+      <key>fft_size</key>
+      <value>1024</value>
+    </param>
+    <param>
+      <key>fft_rate</key>
+      <value>30</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>avg_alpha</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>0, 0, 1, 1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value>displays, 0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(415, 97)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>180</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_scopesink2</key>
+    <param>
+      <key>id</key>
+      <value>orig_scope</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Original Waveform</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>v_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>t_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>1, 0, 1, 1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value>displays, 0</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(414, 425)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>180</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_fftsink2</key>
+    <param>
+      <key>id</key>
+      <value>enc_fft</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Encoded Spectrum</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate*resample</value>
+    </param>
+    <param>
+      <key>baseband_freq</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>y_per_div</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>y_divs</key>
+      <value>8</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>ref_scale</key>
+      <value>2.0</value>
+    </param>
+    <param>
+      <key>fft_size</key>
+      <value>1024</value>
+    </param>
+    <param>
+      <key>fft_rate</key>
+      <value>30</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>avg_alpha</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>1, 0, 1, 1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value>displays, 1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(610, 551)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>180</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_scopesink2</key>
+    <param>
+      <key>id</key>
+      <value>enc_scope</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Encoded Waveform</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate*resample</value>
+    </param>
+    <param>
+      <key>v_scale</key>
+      <value>0.5</value>
+    </param>
+    <param>
+      <key>t_scale</key>
+      <value>20.0/(audio_rate*resample)</value>
+    </param>
+    <param>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>0, 0, 1, 1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value>displays, 1</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(858, 591)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_fftsink2</key>
+    <param>
+      <key>id</key>
+      <value>dec_fft</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Decoded Spectrum</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>baseband_freq</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>y_per_div</key>
+      <value>5</value>
+    </param>
+    <param>
+      <key>y_divs</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>ref_level</key>
+      <value>10</value>
+    </param>
+    <param>
+      <key>ref_scale</key>
+      <value>0.1</value>
+    </param>
+    <param>
+      <key>fft_size</key>
+      <value>1024</value>
+    </param>
+    <param>
+      <key>fft_rate</key>
+      <value>30</value>
+    </param>
+    <param>
+      <key>peak_hold</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>average</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>avg_alpha</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>0, 0, 1, 1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value>displays, 2</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(891, 98)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>180</value>
+    </param>
+  </block>
+  <block>
+    <key>wxgui_scopesink2</key>
+    <param>
+      <key>id</key>
+      <value>dec_scope</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>type</key>
+      <value>float</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>Decoded Waveform</value>
+    </param>
+    <param>
+      <key>samp_rate</key>
+      <value>audio_rate</value>
+    </param>
+    <param>
+      <key>v_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>t_scale</key>
+      <value>0</value>
+    </param>
+    <param>
+      <key>ac_couple</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>xy_mode</key>
+      <value>False</value>
+    </param>
+    <param>
+      <key>num_inputs</key>
+      <value>1</value>
+    </param>
+    <param>
+      <key>grid_pos</key>
+      <value>1, 0, 1, 1</value>
+    </param>
+    <param>
+      <key>notebook</key>
+      <value>displays, 2</value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(889, 422)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>180</value>
+    </param>
+  </block>
+  <block>
+    <key>options</key>
+    <param>
+      <key>id</key>
+      <value>cvsd_sweep</value>
+    </param>
+    <param>
+      <key>_enabled</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>title</key>
+      <value>CVSD Vocoder Test</value>
+    </param>
+    <param>
+      <key>author</key>
+      <value></value>
+    </param>
+    <param>
+      <key>description</key>
+      <value></value>
+    </param>
+    <param>
+      <key>window_size</key>
+      <value>1280, 1024</value>
+    </param>
+    <param>
+      <key>generate_options</key>
+      <value>wx_gui</value>
+    </param>
+    <param>
+      <key>category</key>
+      <value>Custom</value>
+    </param>
+    <param>
+      <key>run</key>
+      <value>True</value>
+    </param>
+    <param>
+      <key>realtime_scheduling</key>
+      <value></value>
+    </param>
+    <param>
+      <key>_coordinate</key>
+      <value>(10, 10)</value>
+    </param>
+    <param>
+      <key>_rotation</key>
+      <value>0</value>
+    </param>
+  </block>
+  <connection>
+    <source_block_id>vco</source_block_id>
+    <sink_block_id>orig_fft</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>tri_source</source_block_id>
+    <sink_block_id>throttle</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>throttle</source_block_id>
+    <sink_block_id>vco</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>vco</source_block_id>
+    <sink_block_id>enc</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>enc</source_block_id>
+    <sink_block_id>blks2_cvsd_decode_0</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>vco</source_block_id>
+    <sink_block_id>orig_scope</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>blks2_cvsd_decode_0</source_block_id>
+    <sink_block_id>dec_fft</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>blks2_cvsd_decode_0</source_block_id>
+    <sink_block_id>dec_scope</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>blks2_cvsd_decode_0</source_block_id>
+    <sink_block_id>audio_sink</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>enc</source_block_id>
+    <sink_block_id>p2u</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>p2u</source_block_id>
+    <sink_block_id>c2f</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>c2f</source_block_id>
+    <sink_block_id>enc_fft</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+  <connection>
+    <source_block_id>c2f</source_block_id>
+    <sink_block_id>enc_scope</sink_block_id>
+    <source_key>0</source_key>
+    <sink_key>0</sink_key>
+  </connection>
+</flow_graph>