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Merge pull request #183 from eshaz/hifi-decode-spectral-nr
hifi-decode: Better resampling, Spectral Noise Reduction, Multi processing
2 parents 0bc2b9a + 61296da commit ce92544

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‎filter_tune/filter_tune.py‎

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@@ -110,7 +110,6 @@
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from matplotlib.figure import Figure
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from vhsdecode.utils import filtfft
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from vhsdecode.addons.FMdeemph import gen_high_shelf
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from vhsdecode.formats import get_format_params
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from vhsdecode import compute_video_filters
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from vhsdecode.main import supported_tape_formats

‎pyproject.toml‎

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@@ -14,7 +14,7 @@ classifiers = [
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"Topic :: Multimedia :: Video",
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]
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dependencies = [
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"numpy>=1.22","numba>=0.58.1","scipy>=1.10.1","samplerate", "static-ffmpeg", "cython", "soundfile", "sounddevice", "importlib_resources >= 5.0; python_version < '3.10'", "matplotlib"
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"numpy>=1.22","numba>=0.58.1","scipy>=1.10.1","samplerate", "static-ffmpeg", "cython", "soundfile", "sounddevice", "importlib_resources >= 5.0; python_version < '3.10'", "matplotlib", "noisereduce>=2.0.0"
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]
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dynamic = ["version"]
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# version = "0.2.1dev0"

‎requirements.txt‎

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@@ -6,3 +6,4 @@ samplerate
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scipy >=1.10,<=1.12
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soundfile
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sounddevice
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noisereduce

‎vhsdecode/addons/FMdeemph.py‎

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@@ -10,58 +10,63 @@
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@njit(cache=True)
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def gen_high_shelf(f0, dbgain, qfactor, fs):
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"""Generate high shelving filter coeficcients (digital).
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f0: The center frequency where the gain in decibel is at half the maximum value.
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Normalized to sampling frequency, i.e output will be filter from 0 to 2pi.
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dbgain: gain at the top of the shelf in decibels
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qfactor: determines shape of filter TODO: Document better
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fs: sampling frequency
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TODO: Generate based on -3db
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Based on: https://www.w3.org/2011/audio/audio-eq-cookbook.html
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"""
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a = 10 ** (dbgain / 40.0)
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w0 = 2 * math.pi * (f0 / fs)
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alpha = math.sin(w0) / (2 * qfactor)
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cosw0 = math.cos(w0)
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asquared = math.sqrt(a)
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def gen_shelf(f0, dbgain, type, fs, qfactor=None, bandwidth=None, slope=None):
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"""Generate shelving filter coefficients (digital).
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* f0:
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The center frequency where the gain in decibel is at half the maximum value.
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Normalized to sampling frequency, i.e output will be filter from 0 to 2pi.
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* dbgain:
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gain at the top of the shelf in decibels
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* fs:
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sampling frequency
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* type:
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"high" for high shelf, "low" for low shelf
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and one of the following:
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* qfactor:
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determines shape of filter TODO: Document better
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* bandwidth:
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bandwidth in octaves between midpoint (dbGain / 2) gain frequencies
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* slope:
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shelf slope. When slope=1, the shelf slope is as steep as it can be and
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remain monotonically increasing or decreasing gain with frequency.
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The shelf slope, in dB/octave, remains proportional to S for all other
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values for a fixed and
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b0 = a * ((a + 1) + (a - 1) * cosw0 + 2 * asquared * alpha)
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b1 = -2 * a * ((a - 1) + (a + 1) * cosw0)
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b2 = a * ((a + 1) + (a - 1) * cosw0 - 2 * asquared * alpha)
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a0 = (a + 1) - (a - 1) * cosw0 + 2 * asquared * alpha
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a1 = 2 * ((a - 1) - (a + 1) * cosw0)
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a2 = (a + 1) - (a - 1) * cosw0 - 2 * asquared * alpha
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return [b0, b1, b2], [a0, a1, a2]
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@njit(cache=True)
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def gen_low_shelf(f0, dbgain, qfactor, fs):
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"""Generate low shelving filter coeficcients (digital).
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f0: The center frequency where the gain in decibel is at half the maximum value.
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Normalized to sampling frequency, i.e output will be filter from 0 to 2pi.
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dbgain: gain at the top of the shelf in decibels
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qfactor: determines shape of filter TODO: Document better
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fs: sampling frequency
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TODO: Generate based on -3db
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Based on: https://www.w3.org/2011/audio/audio-eq-cookbook.html
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"""
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a = 10 ** (dbgain / 40.0)
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w0 = 2 * math.pi * (f0 / fs)
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alpha = math.sin(w0) / (2 * qfactor)
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if qfactor != None:
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alpha = math.sin(w0) / (2 * qfactor)
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elif bandwidth != None:
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alpha = math.sin(w0) * math.sinh((math.log(2) / 2) * bandwidth * (w0 / math.sin(w0)))
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elif slope != None:
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alpha = math.sin(w0 / 2) * math.sqrt((a + 1/ a ) * (1 / slope - 1) + 2)
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else:
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raise Exception("Must specify one value for either qfactor, bandwidth, or slope")
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cosw0 = math.cos(w0)
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asquared = math.sqrt(a)
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b0 = a * ((a + 1) - (a - 1) * cosw0 + 2 * asquared * alpha)
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b1 = 2 * a * ((a - 1) - (a + 1) * cosw0)
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b2 = a * ((a + 1) - (a - 1) * cosw0 - 2 * asquared * alpha)
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a0 = (a + 1) + (a - 1) * cosw0 + 2 * asquared * alpha
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a1 = -2 * ((a - 1) + (a + 1) * cosw0)
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a2 = (a + 1) + (a - 1) * cosw0 - 2 * asquared * alpha
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if type == "low":
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b0 = a * ((a + 1) - (a - 1) * cosw0 + 2 * asquared * alpha)
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b1 = 2 * a * ((a - 1) - (a + 1) * cosw0)
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b2 = a * ((a + 1) - (a - 1) * cosw0 - 2 * asquared * alpha)
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a0 = (a + 1) + (a - 1) * cosw0 + 2 * asquared * alpha
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a1 = -2 * ((a - 1) + (a + 1) * cosw0)
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a2 = (a + 1) + (a - 1) * cosw0 - 2 * asquared * alpha
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elif type == "high":
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b0 = a * ((a + 1) + (a - 1) * cosw0 + 2 * asquared * alpha)
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b1 = -2 * a * ((a - 1) + (a + 1) * cosw0)
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b2 = a * ((a + 1) + (a - 1) * cosw0 - 2 * asquared * alpha)
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a0 = (a + 1) - (a - 1) * cosw0 + 2 * asquared * alpha
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a1 = 2 * ((a - 1) - (a + 1) * cosw0)
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a2 = (a + 1) - (a - 1) * cosw0 - 2 * asquared * alpha
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else:
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raise Exception("Must specify 'high' or 'low' for shelf type, instead got: ", type)
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return [b0, b1, b2], [a0, a1, a2]
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@@ -82,8 +87,14 @@ def __init__(self, fs, dBgain, mid_point, Q=1 / 2):
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# TODO:
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# We want to generate this based on time constant and 'X' value
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# currently we use the mid frequency and a gain to get the correct shape
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# with eyeballed mid value. Q=1/2 seems to give the corret slope.
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self.ataps, self.btaps = gen_high_shelf(mid_point, dBgain, Q, fs)
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# with eyeballed mid value. Q=1/2 seems to give the correct slope.
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self.ataps, self.btaps = gen_shelf(
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mid_point,
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dBgain,
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"high",
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fs,
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qfactor=Q
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)
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def get(self):
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return self.btaps, self.ataps

‎vhsdecode/compute_video_filters.py‎

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@@ -12,7 +12,7 @@
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from importlib.resources import files
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from vhsdecode.utils import filtfft
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from vhsdecode.addons.FMdeemph import FMDeEmphasisB, gen_low_shelf, gen_high_shelf
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from vhsdecode.addons.FMdeemph import FMDeEmphasisB, gen_shelf
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NONLINEAR_AMP_LPF_FREQ_DEFAULT = 700000
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NONLINEAR_STATIC_FACTOR_DEFAULT = None
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file=sys.stderr,
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)
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case "highshelf":
80-
db, da = gen_high_shelf(f["midfreq"], f["gain"], f["q"], freq_hz / 2.0)
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db, da = gen_shelf(f["midfreq"], f["gain"], "high", freq_hz / 2.0, qfactor=f["q"])
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ret *= filtfft((db, da), block_len, whole=False)
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case "lowshelf":
83-
db, da = gen_low_shelf(f["midfreq"], f["gain"], f["q"], freq_hz / 2.0)
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db, da = gen_shelf(f["midfreq"], f["gain"], "low", freq_hz / 2.0, qfactor=f["q"])
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ret *= filtfft((db, da), block_len, whole=False)
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return ret
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