Nuke Audio generator

audiogen.nk

set cut_paste_input [stack 0]
version 14.1 v5
push $cut_paste_input
Expression {
channel0 {rgba.red -rgba.green rgba.blue}
name Expression5
selected true
xpos 2349
ypos -55
addUserKnob {20 User}
addUserKnob {3 sampling l "Sampling Rate"}
sampling 44100
addUserKnob {1 song l Song}
song "E4, D#4, E4, D#4, E4, B3, D4, C4, A3, (A3 C3), (A3 E2), (A3 A2), (A3 C3), \nE3, A3, B3, (B3 E2), (B3 G#2), (B3 E3), \nG#3, B3, C4, (C4 E2), (C4 A2), (C4 E3), \nE4, D#4, E4, D#4, E4, B3, D4, C4, A3, (A3 E2), (A3 A2), (A3 C3), \nE3, A3, B3, (B3 E2), (B3 A2), (B3 G#2), (B3 E3), \nC4, B3, A3, (A3 E2), (A3 A2), A3 ,\n\nE4, D#4, E4, D#4, E4, B3, D4, C4, A3,(A3 E2), (A3 A2), (A3 C3), \nE3, A3, B3, (B3 E2), (B3 G#2), (B3 E3),\nG#3, B3, C4,(C4 E2), E3,\nE4, D#4, E4, D#4, E4, B3, D4, C4, A3, (A3 E2), A2, C3, E3, A3, \n B3, (B3 E2), G#2, E3, C4, B3, A3, (A3 E2), A2, B3, C4, D4, E4, (E4 G2), (E4 C3), (E4 G3), F4, E4, \nD4, (D4 G2), (D4 B2), (D4 F3), E4, D4, C4, (C4 E2), (C4 A2), (C4 E3), D4, C4, B3, (B3 E2), E3, E3, E4, E3, E4, E4,, \nE4, D#4, E4, D#4, E4,B3, D4, C4, A3,(A3 E2), A2, C3, E3, A3, B3, (B3 E2), G#2, E3, G#3, B3, C4, (C4 E2), A2, E3,\nE4, D#4, E4, D#4, E4, B3, D4, C4, A3, (A3 E2), A2, C3, E3, A2, B3, (B3 E2), G#2, E3\n"
addUserKnob {22 generate l Generate T "import math\nimport re\n\n# --- Configuration ---\nA4_FREQ = 440.0  # Frequency of A4 note\n\n# Semitone values relative to C in an octave (C=0, C#=1, ..., B=11)\n# This map helps convert note names (like 'A', 'C') to a base semitone value.\nNOTE_TO_SEMITONE_MAP = \{\n    'C': 0, 'D': 2, 'E': 4, 'F': 5, 'G': 7, 'A': 9, 'B': 11\n\}\n# Reference for A4: Octave 4, Note 'A'\nA4_OCTAVE = 4\nA4_SEMITONE_OFFSET_IN_OCTAVE = NOTE_TO_SEMITONE_MAP\['A']  # Should be 9\n# Calculate the number of semitones A4 is from C0 (C in octave 0)\nNUM_SEMITONES_A4_FROM_C0 = A4_OCTAVE * 12 + A4_SEMITONE_OFFSET_IN_OCTAVE\n\n\ndef get_note_frequency(note_str: str) -> float:\n    \"\"\"\n    Calculates the frequency of a given musical note string.\n    Args:\n        note_str: The note string, e.g., \"A4\", \"C#3\", \"B#2\".\n                  Handles sharps (#). B# is treated as C of the next octave,\n                  E# is treated as F of the same octave.\n    Returns:\n        The frequency of the note in Hz.\n    Raises:\n        ValueError: If the note format is invalid.\n    \"\"\"\n    note_str = note_str.strip()\n    # Regex for notes like C4, A#3. Octaves 0-8. Sharp is optional.\n    # Example: \"A#3\" -> name='A', sharp_char='#', octave_str='3'\n    # Example: \"C4\"  -> name='C', sharp_char='',  octave_str='4'\n    match = re.fullmatch(r'(\[A-G])(\[#]?)(\[0-8])', note_str)\n    if not match:\n        raise ValueError(\n            f\"Invalid note format: '\{note_str\}'. Expected format e.g., 'A4', 'C#3'.\"\n        )\n\n    name, sharp_char, octave_str = match.groups()\n    octave = int(octave_str)\n\n    semitone_offset = NOTE_TO_SEMITONE_MAP\[name]\n\n    if sharp_char == '#':\n        semitone_offset += 1\n    \n    # Normalize semitone offset and octave for cases like B# or E#\n    # If semitone_offset becomes 12 (e.g., B#), it's C (0) of the next octave.\n    # If semitone_offset becomes 5 due to E# (E=4 + #=1), it's F (5), no octave change needed unless it goes >=12.\n    if semitone_offset >= 12:\n        semitone_offset -= 12  # Wrap around to 0 (C)\n        octave += 1\n    \n    # Calculate the total number of semitones from C0 for the current note\n    num_semitones_current_note_from_C0 = octave * 12 + semitone_offset\n\n    # Calculate the difference in semitones from A4\n    semitone_diff_from_A4 = num_semitones_current_note_from_C0 - NUM_SEMITONES_A4_FROM_C0\n    \n    # Calculate frequency using the formula: f = f_ref * (2^(1/12))^n\n    frequency = A4_FREQ * (2**(semitone_diff_from_A4 / 12.0))\n    return frequency\n\n\ndef get_bin_for_frequency(frequency: float, fftsize: int, sampling_rate: float) -> int:\n    \"\"\"\n    Calculates the nearest FFT bin index for a given frequency.\n    Args:\n        frequency: The frequency in Hz.\n        fftsize: The size of the FFT.\n        sampling_rate: The sampling rate in Hz.\n    Returns:\n        The nearest FFT bin index.\n    Raises:\n        ValueError: If fftsize or sampling_rate are not positive.\n    \"\"\"\n    if fftsize <= 0:\n        raise ValueError(\"FFT size must be positive.\")\n    if sampling_rate <= 0:\n        raise ValueError(\"Sampling rate must be positive.\")\n\n    if frequency == 0: # Should generally not be the case for musical notes\n        return 0\n        \n    # Frequency resolution: df = sampling_rate / fftsize\n    # Bin index k for frequency f: f = k * df  => k = f / df = f * fftsize / sampling_rate\n    bin_index_float = frequency * fftsize / sampling_rate\n    bin_index = round(bin_index_float)\n\n    # Ensure bin_index is within the valid range \[0, fftsize - 1]\n    # The FFT output has 'fftsize' bins, indexed 0 to fftsize-1.\n    return max(0, min(int(bin_index), fftsize - 1))\n\n\ndef generate_expression(input_music_string: str, fftsize: int, sampling_rate: float) -> str:\n    \"\"\"\n    Generates the expression string from the input music notation.\n    Args:\n        input_music_string: The music string, e.g., \"A4, 0, (C4 E4 G4), B#2\".\n        fftsize: The FFT size.\n        sampling_rate: The sampling rate.\n    Returns:\n        The generated expression string.\n    \"\"\"\n    time_events_raw = input_music_string.split(',')\n    time_sample_index = 0  # 'y' in the output expression\n    conditions = \[]\n\n    for time_event_str_raw in time_events_raw:\n        time_event_str = time_event_str_raw.strip()\n        \n        # If the part after split is empty (e.g. \"A1,\"), it's an empty time step.\n        # It will not generate notes, but time_sample_index will still advance.\n        if not time_event_str:\n            time_sample_index += 1\n            continue\n\n        notes_for_current_sample = \[]\n\n        if time_event_str == '0':\n            # Silence for this time sample, no notes to add.\n            pass\n        elif time_event_str.startswith('(') and time_event_str.endswith(')'):\n            # Chord: (Note1 Note2 Note3)\n            chord_content = time_event_str\[1:-1].strip()\n            if chord_content: # Ensure not an empty chord \"()\"\n                # Notes within a chord are space-separated\n                note_strs_in_chord = chord_content.split()\n                for note_str in note_strs_in_chord:\n                    notes_for_current_sample.append(note_str.strip())\n        else:\n            # Single note\n            notes_for_current_sample.append(time_event_str)\n\n        for note_to_process in notes_for_current_sample:\n            try:\n                frequency = get_note_frequency(note_to_process)\n                bin_index = get_bin_for_frequency(frequency, fftsize, sampling_rate)\n                # Add condition: x == bin_index AND y == time_sample_index\n                conditions.append(f\"x==\{bin_index\}&&y==\{time_sample_index\}\")\n            except ValueError as e:\n                # Print a warning and skip this invalid note.\n                print(f\"Warning: Skipping invalid note '\{note_to_process\}' at time sample \{time_sample_index\}: \{e\}\")\n        \n        time_sample_index += 1  # Move to the next time sample\n\n    # Join all conditions with OR operator\n    return \"||\".join(conditions)\n\nnode = nuke.thisNode()\nsong = node\['song'].value()\nresult = generate_expression(song, (node.width()-1)*2, node\['sampling'].value())\nnode\['expr0'].setValue(result)" +STARTLINE}
}