diff --git a/pydub/scipy_effects.py b/pydub/scipy_effects.py index 1597504..177c4ff 100644 --- a/pydub/scipy_effects.py +++ b/pydub/scipy_effects.py @@ -10,7 +10,7 @@ provided by pydub.effects. """ from scipy.signal import butter, sosfilt -from .utils import register_pydub_effect +from .utils import (register_pydub_effect,stereo_to_ms,ms_to_stereo) def _mk_butter_filter(freq, type, order): @@ -62,3 +62,114 @@ def high_pass_filter(seg, cutoff_freq, order=5): def low_pass_filter(seg, cutoff_freq, order=5): filter_fn = _mk_butter_filter(cutoff_freq, 'lowpass', order=order) return seg.apply_mono_filter_to_each_channel(filter_fn) + + +@register_pydub_effect +def _eq(seg, focus_freq, bandwidth=100, mode="peak", gain_dB=0, order=2): + """ + Args: + focus_freq - middle frequency or known frequency of band (in Hz) + bandwidth - range of the equalizer band + mode - Mode of Equalization(Peak/Notch(Bell Curve),High Shelf, Low Shelf) + order - Rolloff factor(1 - 6dB/Octave 2 - 12dB/Octave) + + Returns: + Equalized/Filtered AudioSegment + """ + filt_mode = ["peak", "low_shelf", "high_shelf"] + if mode not in filt_mode: + raise ValueError("Incorrect Mode Selection") + + if gain_dB >= 0: + if mode == "peak": + sec = band_pass_filter(seg, focus_freq - bandwidth/2, focus_freq + bandwidth/2, order = order) + seg = seg.overlay(sec - (3 - gain_dB)) + return seg + + if mode == "low_shelf": + sec = low_pass_filter(seg, focus_freq, order=order) + seg = seg.overlay(sec - (3 - gain_dB)) + return seg + + if mode == "high_shelf": + sec = high_pass_filter(seg, focus_freq, order=order) + seg = seg.overlay(sec - (3 - gain_dB)) + return seg + + if gain_dB < 0: + if mode == "peak": + sec = high_pass_filter(seg, focus_freq - bandwidth/2, order=order) + seg = seg.overlay(sec - (3 + gain_dB)) + gain_dB + sec = low_pass_filter(seg, focus_freq + bandwidth/2, order=order) + seg = seg.overlay(sec - (3 + gain_dB)) + gain_dB + return seg + + if mode == "low_shelf": + sec = high_pass_filter(seg, focus_freq, order=order) + seg = seg.overlay(sec - (3 + gain_dB)) + gain_dB + return seg + + if mode=="high_shelf": + sec=low_pass_filter(seg, focus_freq, order=order) + seg=seg.overlay(sec - (3 + gain_dB)) +gain_dB + return seg + + +@register_pydub_effect +def eq(seg, focus_freq, bandwidth=100, channel_mode="L+R", filter_mode="peak", gain_dB=0, order=2): + """ + Args: + focus_freq - middle frequency or known frequency of band (in Hz) + bandwidth - range of the equalizer band + channel_mode - Select Channels to be affected by the filter. + L+R - Standard Stereo Filter + L - Only Left Channel is Filtered + R - Only Right Channel is Filtered + M+S - Blumlien Stereo Filter(Mid-Side) + M - Only Mid Channel is Filtered + S - Only Side Channel is Filtered + Mono Audio Segments are completely filtered. + filter_mode - Mode of Equalization(Peak/Notch(Bell Curve),High Shelf, Low Shelf) + order - Rolloff factor(1 - 6dB/Octave 2 - 12dB/Octave) + + Returns: + Equalized/Filtered AudioSegment + """ + filt_mode = ["L+R", "M+S", "L", "R", "M", "S"] + if mode not in filt_mode: + raise ValueError("Incorrect Channel Mode Selection") + + if seg.channels == 1: + return _eq(seg, focus_freq, bandwidth, filter_mode, gain_dB, order) + + if channel_mode == "L+R": + return _eq(seg, focus_freq, bandwidth, filter_mode, gain_dB, order) + + if channel_mode == "L": + seg = seg.split_to_mono() + seg = [_eq(seg[0], focus_freq, bandwidth, filter_mode, gain_dB, order), seg[1]] + return AudioSegment.from_mono_audio_segements(seg[0], seg[1]) + + if channel_mode == "R": + seg = seg.split_to_mono() + seg = [seg[0], _eq(seg[1], focus_freq, bandwidth, filter_mode, gain_dB, order)] + return AudioSegment.from_mono_audio_segements(seg[0], seg[1]) + + if channel_mode == "M+S": + seg = stereo_to_ms(seg) + seg = _eq(seg, focus_freq, bandwidth, filter_mode, gain_dB, order) + return ms_to_stereo(seg) + + if channel_mode == "M": + seg = stereo_to_ms(seg).split_to_mono() + seg = [_eq(seg[0], focus_freq, bandwidth, filter_mode, gain_dB, order), seg[1]] + seg = AudioSegment.from_mono_audio_segements(seg[0], seg[1]) + return ms_to_stereo(seg) + + if channel_mode == "S": + seg = stereo_to_ms(seg).split_to_mono() + seg = [seg[0], _eq(seg[1], focus_freq, bandwidth, filter_mode, gain_dB, order)] + seg = AudioSegment.from_mono_audio_segements(seg[0], seg[1]) + return ms_to_stereo(seg) + + diff --git a/pydub/utils.py b/pydub/utils.py index 448d65f..740c500 100644 --- a/pydub/utils.py +++ b/pydub/utils.py @@ -415,3 +415,20 @@ def get_supported_decoders(): def get_supported_encoders(): return get_supported_codecs()[1] + +def stereo_to_ms(audio_segment): + ''' + Left-Right -> Mid-Side + ''' + channel = audio_segment.split_to_mono() + channel = [channel[0].overlay(channel[1]), channel[0].overlay(channel[1].invert_phase())] + return AudioSegment.from_mono_audiosegments(channel[0], channel[1]) + +def ms_to_stereo(audio_segment): + ''' + Mid-Side -> Left-Right + ''' + channel = audio_segment.split_to_mono() + channel = [channel[0].overlay(channel[1]) - 3, channel[0].overlay(channel[1].invert_phase()) - 3] + return AudioSegment.from_mono_audiosegments(channel[0], channel[1]) +