File size: 7,993 Bytes
32b0a98
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
#!/usr/bin/env python3
"""Export PrimeTTS v2 (MB-iSTFT-VITS, Xinran G_400000) to ONNX for the demo Space
(ORT-CPU). opset17, dynamo=False per the project's validated export contract.

torch.istft has no ONNX op, so the tiny gen-head iSTFT (n_fft=16, hop=4) is replaced
by an exact equivalent: irFFT as a fixed matrix product + windowed overlap-add via
ConvTranspose1d + window-envelope normalization (verified vs torch.istft before export).

Inputs : x[1,T] int64, tone[1,T] int64, lang[1,T] int64, x_lengths[1] int64,
         noise_scale[1] f32, length_scale[1] f32
Output : wav[1,1,L] f32 @16kHz
"""
import argparse, json, math, os, sys

import numpy as np
import torch

_ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
sys.path.insert(0, _ROOT)

from models import SynthesizerTrn
import models as models_mod


class OnnxISTFT(torch.nn.Module):
    """Drop-in for TorchSTFT.inverse (center=True), ONNX-exportable, exact."""

    def __init__(self, n_fft, hop, window):
        super().__init__()
        self.n_fft, self.hop = n_fft, hop
        n_bins = n_fft // 2 + 1
        k = torch.arange(n_bins).unsqueeze(1).float()
        n = torch.arange(n_fft).unsqueeze(0).float()
        coef = torch.full((n_bins, 1), 2.0)
        coef[0, 0] = 1.0
        if n_fft % 2 == 0:
            coef[-1, 0] = 1.0
        ang = 2 * math.pi * k * n / n_fft
        self.register_buffer("C", (coef * torch.cos(ang)) / n_fft)   # [bins, n_fft]
        self.register_buffer("S", (-coef * torch.sin(ang)) / n_fft)  # [bins, n_fft]
        self.register_buffer("win", window.reshape(1, -1, 1))        # [1, n_fft, 1]
        ola_k = torch.eye(n_fft).unsqueeze(1)                        # [n_fft,1,n_fft]
        self.register_buffer("ola_kernel", ola_k)
        self.register_buffer("env_kernel", (window ** 2).reshape(1, 1, -1))

    def inverse(self, magnitude, phase):
        real = magnitude * torch.cos(phase)          # [B, bins, T]
        imag = magnitude * torch.sin(phase)
        # frames[b, n, t] = sum_k real[b,k,t]*C[k,n] + imag[b,k,t]*S[k,n]
        frames = torch.einsum("bkt,kn->bnt", real, self.C) + \
                 torch.einsum("bkt,kn->bnt", imag, self.S)
        frames = frames * self.win                                   # analysis window
        y = torch.nn.functional.conv_transpose1d(frames, self.ola_kernel, stride=self.hop)
        ones = torch.ones_like(frames[:, :1, :])
        env = torch.nn.functional.conv_transpose1d(ones, self.env_kernel, stride=self.hop)
        y = y / torch.clamp(env, min=1e-9)
        half = self.n_fft // 2
        y = y[:, :, half:-half]                                      # center=True trim
        return y  # [B,1,L] (matches TorchSTFT.inverse's unsqueeze(-2))


class ExportWrapper(torch.nn.Module):
    def __init__(self, net):
        super().__init__()
        self.net = net

    def forward(self, x, tone, lang, x_lengths, sid, noise_scale, length_scale):
        o, *_ = self.net.infer(x, tone, lang, x_lengths, sid=sid,
                               noise_scale=noise_scale, length_scale=length_scale)
        return o


def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("--ckpt", default="/home/luigi/mbvits_run/keep_v21b_12500_G.pth")
    ap.add_argument("--config", default=os.path.join(_ROOT, "configs", "zhtw_mb_istft_16k_v21b.json"))
    ap.add_argument("--out", default="/home/luigi/mbvits_run/primetts_v21_3voice.onnx")
    args = ap.parse_args()

    cfg = json.load(open(args.config))
    m, d = cfg["model"], cfg["data"]
    net = SynthesizerTrn(88, d["filter_length"] // 2 + 1,
                         cfg["train"]["segment_size"] // d["hop_length"], **m)
    sd = torch.load(args.ckpt, map_location="cpu", weights_only=False)["model"]
    sd = {(k[7:] if k.startswith("module.") else k): v for k, v in sd.items()}
    net.load_state_dict(sd, strict=True)
    net.eval()
    net.dec.remove_weight_norm()

    # numeric check of OnnxISTFT vs torch.istft BEFORE swapping it in
    ts = net.dec.stft if hasattr(net.dec, "stft") else None
    # Multiband generator constructs TorchSTFT inline in forward via module-level import;
    # check models.py: it uses `stft.inverse(...)` where stft is built in forward? Inspect:
    oi = OnnxISTFT(m["gen_istft_n_fft"], m["gen_istft_hop_size"],
                   torch.hann_window(m["gen_istft_n_fft"]))
    from stft import TorchSTFT
    ref = TorchSTFT(filter_length=m["gen_istft_n_fft"], hop_length=m["gen_istft_hop_size"],
                    win_length=m["gen_istft_n_fft"])
    mag = torch.rand(4, m["gen_istft_n_fft"] // 2 + 1, 57) + 0.1
    ph = (torch.rand(4, m["gen_istft_n_fft"] // 2 + 1, 57) - 0.5) * 2 * math.pi
    a = ref.inverse(mag, ph)
    b = oi.inverse(mag, ph)
    err = (a - b).abs().max().item()
    print(f"[istft-check] torch vs onnx-istft max abs err = {err:.3e}  shapes {tuple(a.shape)} {tuple(b.shape)}")
    assert err < 1e-4, "OnnxISTFT mismatch"

    # swap: the MB generator calls `stft.inverse(spec, phase)` on a TorchSTFT instance
    # created in its forward (models.py line ~330: stft = TorchSTFT(...).to(x.device)).
    # Patch the class used by models.py so the instance built in forward IS ours.
    class PatchedTorchSTFT(torch.nn.Module):
        def __init__(self, filter_length=16, hop_length=4, win_length=16, window="hann"):
            super().__init__()
            self._oi = OnnxISTFT(filter_length, hop_length, torch.hann_window(win_length))
        def inverse(self, magnitude, phase):
            return self._oi.inverse(magnitude, phase)
        def to(self, *a, **k):
            return self
    models_mod.TorchSTFT = PatchedTorchSTFT
    import stft as stft_mod
    stft_mod.TorchSTFT = PatchedTorchSTFT

    # PQMF hardcodes .cuda(); rebuild it CPU-safe with identical filters
    from pqmf import design_prototype_filter

    class CpuPQMF(torch.nn.Module):
        def __init__(self, device=None, subbands=4, taps=62, cutoff_ratio=0.15, beta=9.0):
            super().__init__()
            h_proto = design_prototype_filter(taps, cutoff_ratio, beta)
            h_synthesis = np.zeros((subbands, len(h_proto)))
            for k in range(subbands):
                h_synthesis[k] = 2 * h_proto * np.cos(
                    (2 * k + 1) * (np.pi / (2 * subbands)) *
                    (np.arange(taps + 1) - ((taps - 1) / 2)) - (-1) ** k * np.pi / 4)
            self.register_buffer("synthesis_filter",
                                 torch.from_numpy(h_synthesis).float().unsqueeze(0))
            updown = torch.zeros((subbands, subbands, subbands))
            for k in range(subbands):
                updown[k, k, 0] = 1.0
            self.register_buffer("updown_filter", updown)
            self.subbands = subbands
            self.pad_fn = torch.nn.ConstantPad1d(taps // 2, 0.0)

        def synthesis(self, x):
            x = torch.nn.functional.conv_transpose1d(
                x, self.updown_filter * self.subbands, stride=self.subbands)
            return torch.nn.functional.conv1d(self.pad_fn(x), self.synthesis_filter)

        def to(self, *a, **k):
            return self

    models_mod.PQMF = CpuPQMF

    wrap = ExportWrapper(net)
    T = 33
    ex = (torch.randint(1, 87, (1, T)), torch.randint(0, 6, (1, T)),
          torch.randint(0, 2, (1, T)), torch.tensor([T], dtype=torch.long),
          torch.tensor([0], dtype=torch.long), torch.tensor([0.667], dtype=torch.float32), torch.tensor([1.0], dtype=torch.float32))
    with torch.no_grad():
        wav = wrap(*ex)
    print(f"[trace-check] eager wav {tuple(wav.shape)}")

    torch.onnx.export(
        wrap, ex, args.out, opset_version=17, dynamo=False,
        input_names=["x", "tone", "lang", "x_lengths", "sid", "noise_scale", "length_scale"],
        output_names=["wav"],
        dynamic_axes={"x": {1: "T"}, "tone": {1: "T"}, "lang": {1: "T"}, "wav": {2: "L"}},
    )
    print(f"[export] wrote {args.out} ({os.path.getsize(args.out)/1e6:.1f} MB)")


if __name__ == "__main__":
    main()