def test_create_random_noise(self):
spectro, _metadata = SoundProcessor.load_spectrogram(
self.one_spectro_file)
new_spectro, _fname = SoundProcessor.random_noise(spectro,
noise_type='uniform')
self.assertTrue((new_spectro > spectro).any())
self.assertTrue((new_spectro <= 255).all())
def create_new_sample(self, sample_path, out_dir, method):
'''
Given one spectrogram file, and an image augmentation
method name, compute that augmentation, create a file name
that gives insight into the aug applied, and write that
new spectrogram file to out_dir.
Currently available types of image augmentation technique:
o adding random or uniform sounds
o frequency masking
o time masking
Returns the full path of the newly created spectrogram file:
:param sample_path: absolute path to spectrogram
:type sample_path: str
:param out_dir: destination of resulting new spectros
:type out_dir: src
:param method: the (spectrogram) image augmentation method to apply
:type method: ImgAugMethod
:return: Newly created spectro file (full path) or None,
if a failure occurred.
:rtype: {str | None|
'''
success = False
spectro, metadata = SoundProcessor.load_spectrogram(sample_path)
if method == ImgAugMethod.NOISE:
try:
# Default is uniform noise:
new_spectro, out_fname = SoundProcessor.random_noise(spectro)
metadata['augmentation'] = 'noise'
success = True
except Exception as e:
sample_fname = Path(sample_path).stem
self.log.err(
f"Failed to add noise to {sample_fname} ({repr(e)})")
elif method == ImgAugMethod.FMASK:
try:
# Horizontal bands:
new_spectro, out_fname = SoundProcessor.freq_mask(
spectro,
max_height=15 # num freq bands
)
metadata['augmentation'] = 'fmask'
success = True
except Exception as e:
sample_fname = Path(sample_path).stem
self.log.err(
f"Failed to time shift on {sample_fname} ({repr(e)})")
elif method == ImgAugMethod.TMASK:
try:
# Vertical bands:
new_spectro, out_fname = SoundProcessor.time_mask(
spectro,
max_width=15 # num time ticks
)
metadata['augmentation'] = 'tmask'
success = True
except Exception as e:
sample_fname = Path(sample_path).stem
self.log.err(
f"Failed to time shift on {sample_fname} ({repr(e)})")
if success:
sample_p = Path(sample_path)
appended_fname = sample_p.stem + out_fname + sample_p.suffix
out_path = os.path.join(out_dir, appended_fname)
SoundProcessor.save_image(new_spectro, out_path, metadata)
return out_path if success else None