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hifi-decode: Muting during carrier loss#199

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oyvindln merged 3 commits intooyvindln:vhs_decodefrom
eshaz:hifi-decode-muting
Mar 4, 2025
Merged

hifi-decode: Muting during carrier loss#199
oyvindln merged 3 commits intooyvindln:vhs_decodefrom
eshaz:hifi-decode-muting

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@eshaz
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@eshaz eshaz commented Mar 1, 2025 •
edited
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Changes

  • Add option to mute audio when the Hifi carrier is lost.
    • This works by detecting broadband noise in the frequency area above the audible range.
    • When the noise reaches a threshold (currently set to 100%, i.e. clipping), and the standard deviation of the fft is greater than 1, the audio is muted
    • Each mute is padded with a fade out / fade in to prevent pops and harmonics from the mute transition.

Example

  • Small example clip of decoded audio with and without muting. I shuttled the tape around a bit during the capture to demonstrate the granularity of the muting.

With Muting

https://discord.com/channels/665557267189334046/665834485975351307/1345259858466701443

Without Muting

https://discord.com/channels/665557267189334046/665834485975351307/1345259899025625090

@Inky1003
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Inky1003 commented Mar 1, 2025

For some reason this branch is not working for me. Tried to decode a 40MSPS flac and this happened:

Process Process-1:
Traceback (most recent call last):
  File "/home/inky/.pyenv/versions/3.12.9/lib/python3.12/multiprocessing/process.py", line 314, in _bootstrap
    self.run()
  File "/home/inky/.pyenv/versions/3.12.9/lib/python3.12/multiprocessing/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1453, in hifi_decode_worker
    decode_next_block()
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1430, in decode_next_block
    audioL, audioR = decoder.block_decode(raw_data, decoder_state.post_audio_len, measure_perf)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1327, in block_decode
    preL, dcL, perf_measurements_l = HiFiDecode.demod_process_audio(filterL, self.fmL, self.audio_process_params, measure_perf)
                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1255, in demod_process_audio
    fm.work(filtered, audio)
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 283, in work
    DecoderSharedMemory.copy_data_float32(self.htdeFM(input, self.samp_rate), output, len(output))
                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 208, in htdeFM
    return unwrap_hilbert(hilbert(data), samp_rate)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/numba/core/dispatcher.py", line 424, in _compile_for_args
    error_rewrite(e, 'typing')
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/numba/core/dispatcher.py", line 365, in error_rewrite
    raise e.with_traceback(None)
numba.core.errors.TypingError: Failed in nopython mode pipeline (step: nopython frontend)
No implementation of function Function(<function ediff1d at 0x73a08e931b20>) found for signature:
 
 >>> ediff1d(array(float32, 1d, C), to_begin=Literal[int](0))
 
There are 2 candidate implementations:
  - Of which 2 did not match due to:
  Overload in function 'np_ediff1d': File: numba/np/old_arraymath.py: Line 2128.
    With argument(s): '(array(float32, 1d, C), to_begin=int64)':
   Rejected as the implementation raised a specific error:
     NumbaTypeError: dtype of to_begin must be compatible with input ary
  raised from /home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/numba/np/old_arraymath.py:2148

During: resolving callee type: Function(<function ediff1d at 0x73a08e931b20>)
During: typing of call at /home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/lddecode/utils.py (764)


File "lib/python3.12/site-packages/lddecode/utils.py", line 764:
    def unwrap_hilbert(hilbert, freq_hz):
        <source elided>
        tangles = np.angle(hilbert)
        dangles = np.ediff1d(tangles, to_begin=0).real
        ^

During: Pass nopython_type_inference
Process Process-3:
Traceback (most recent call last):
  File "/home/inky/.pyenv/versions/3.12.9/lib/python3.12/multiprocessing/process.py", line 314, in _bootstrap
    self.run()
  File "/home/inky/.pyenv/versions/3.12.9/lib/python3.12/multiprocessing/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1453, in hifi_decode_worker
    decode_next_block()
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1430, in decode_next_block
    audioL, audioR = decoder.block_decode(raw_data, decoder_state.post_audio_len, measure_perf)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1327, in block_decode
    preL, dcL, perf_measurements_l = HiFiDecode.demod_process_audio(filterL, self.fmL, self.audio_process_params, measure_perf)
                                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 1255, in demod_process_audio
    fm.work(filtered, audio)
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 283, in work
    DecoderSharedMemory.copy_data_float32(self.htdeFM(input, self.samp_rate), output, len(output))
                                          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/vhsdecode/hifi/HiFiDecode.py", line 208, in htdeFM
    return unwrap_hilbert(hilbert(data), samp_rate)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/numba/core/dispatcher.py", line 424, in _compile_for_args
    error_rewrite(e, 'typing')
  File "/home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/numba/core/dispatcher.py", line 365, in error_rewrite
    raise e.with_traceback(None)
numba.core.errors.TypingError: Failed in nopython mode pipeline (step: nopython frontend)
No implementation of function Function(<function ediff1d at 0x73a08e931b20>) found for signature:
 
 >>> ediff1d(array(float32, 1d, C), to_begin=Literal[int](0))
 
There are 2 candidate implementations:
  - Of which 2 did not match due to:
  Overload in function 'np_ediff1d': File: numba/np/old_arraymath.py: Line 2128.
    With argument(s): '(array(float32, 1d, C), to_begin=int64)':
   Rejected as the implementation raised a specific error:
     NumbaTypeError: dtype of to_begin must be compatible with input ary
  raised from /home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/numba/np/old_arraymath.py:2148

During: resolving callee type: Function(<function ediff1d at 0x73a08e931b20>)
During: typing of call at /home/inky/Downloads/vhs-decode_eshaz_branch/lib/python3.12/site-packages/lddecode/utils.py (764)


File "lib/python3.12/site-packages/lddecode/utils.py", line 764:
    def unwrap_hilbert(hilbert, freq_hz):
        <source elided>
        tangles = np.angle(hilbert)
        dangles = np.ediff1d(tangles, to_begin=0).real
        ^

During: Pass nopython_type_inference

CLI was

python3.12 vhsdecode/hifi/main.py --ar 96000 --normalize --original --noise_reduction on --auto_fine_tune on --pm --muting on (infile) (outfile)

@eshaz
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eshaz commented Mar 2, 2025

@Inky1003 Try removing the --original from your cli command.

I have had issues with --original for some time now, and it's not related to this PR. I can probably fix it though. I'll take a look.

@eshaz
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eshaz commented Mar 3, 2025 •
edited
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@Inky1003 I fixed the --original parameter. Try out this commit eshaz@614567b.

I've removed the changes in this PR, so there won't be any merge conflicts when the latest ld-decode changes get pulled in by @oyvindln. The --original parameter will work after this PR is merged, and then after happycube@614567b from ld-decode is pulled in.

eshaz added a commit to eshaz/vhs-decode that referenced this pull request Mar 3, 2025
@eshaz
fix datatype miss-match for hifi-decode see oyvindln#199
614567b
happycube added a commit to happycube/ld-decode that referenced this pull request Mar 3, 2025
@happycube
Merge pull request #909 from eshaz/patch-3
a8c5b15 
fix datatype miss-match for hifi-decode see oyvindln#199
@eshaz eshaz force-pushed the hifi-decode-muting branch from 5e74368 to 1d58397 Compare March 3, 2025 05:02
@eshaz eshaz force-pushed the hifi-decode-muting branch from 1d58397 to 84cc61c Compare March 3, 2025 05:03
@oyvindln oyvindln merged commit df1a814 into oyvindln:vhs_decode Mar 4, 2025
@eshaz eshaz deleted the hifi-decode-muting branch March 8, 2025 16:49
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3 participants

@eshaz @Inky1003 @oyvindln