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import torch
from torch import nn
import torch.nn.functional as F
from omegaconf import OmegaConf
import numpy as np
from huggingface_hub import hf_hub_download
import os
from torch.nn.utils import weight_norm
from transformers import T5EncoderModel, T5Tokenizer  # type: ignore
from einops import rearrange

torch.backends.cuda.enable_mem_efficient_sdp(True)



N_REPEAT = 2  # num (virtual batch_size) clones of audio sounds

def _shift(x):
    #print(x.shape, 'BATCH Independent SHIFT\n AudioGen')
    for i, _slice in enumerate(x):
        n = x.shape[2]
        offset = np.random.randint(.24 * n, max(1, .74 * n))  # high should be above >= 0 TBD
        print(offset)
        x[i, :, :] = torch.roll(_slice, offset, dims=1)  # _slice 2D
    return x

class AudioGen(torch.nn.Module):

    # https://huggingface.co/facebook/audiogen-medium

    def __init__(self):

        super().__init__()
        _file_1 = hf_hub_download(
            repo_id='facebook/audiogen-medium',
            filename="compression_state_dict.bin",
            cache_dir=os.environ.get('AUDIOCRAFT_CACHE_DIR', None),
            library_name="audiocraft",
            library_version= '1.3.0a1')  # Found at __init__.py #audiocraft.__version__)
        pkg = torch.load(_file_1, map_location='cpu')# kwargs = OmegaConf.create(pkg['xp.cfg'])
        self.compression_model = EncodecModel()
        self.compression_model.load_state_dict(pkg['best_state'], strict=False)
        self.compression_model.eval()  # ckpt has also unused encoder weights
        self._chunk_len = 476
        _file_2 = hf_hub_download(
            repo_id='facebook/audiogen-medium',
            filename="state_dict.bin",
            cache_dir=os.environ.get('AUDIOCRAFT_CACHE_DIR', None),
            library_name="audiocraft",
            library_version= '1.3.0a1')  # Found at __init__.py #audiocraft.__version__)
        pkg = torch.load(_file_2, map_location='cpu')
        cfg = OmegaConf.create(pkg['xp.cfg'])  # CFG inside torch bin
        _best = pkg['best_state']
        _best['t5.output_proj.weight'] = _best.pop('condition_provider.conditioners.description.output_proj.weight')#.to(torch.float)
        _best['t5.output_proj.bias'] = _best.pop('condition_provider.conditioners.description.output_proj.bias')#.to(torch.float)
        self.lm = LMModel()
        self.lm.load_state_dict(pkg['best_state'], strict=True)
        self.lm.eval()


    @torch.no_grad()
    def generate(self,
                 prompt='dogs mewo',
                 duration=2.24,  # seconds of audio
                 cache_lim=71,   # flush kv cache after cache_lim tok
                 ):
        torch.manual_seed(42)  # https://github.com/facebookresearch/audiocraft/issues/111#issuecomment-1614732858
        self.lm.cache_lim = cache_lim
        self.lm.n_draw = int(.8 * duration) + 1  # different beam every 0.47 seconds of audio
        with torch.autocast(device_type='cpu', dtype=torch.bfloat16):
            gen_tokens = self.lm.generate(
                text_condition=[prompt] * N_REPEAT  + [''] * N_REPEAT,#['dogs', 'dogs...!', '', '']
                max_tokens=int(.04 * duration / N_REPEAT * self.compression_model.frame_rate) + 12) # [bs, 4, 74*self.lm.n_draw]

        # OOM if vocode all tokens
        x = []


        for i in range(7, gen_tokens.shape[2], self._chunk_len):  # min soundscape 2s assures 10 tokens

            decoded_chunk = self.compression_model.decode(gen_tokens[:, :, i-7:i+self._chunk_len])

            x.append(decoded_chunk)
            
        x = torch.cat(x, 2)  # [bs, 1, 114000]

        x = _shift(x)  # clone() to have xN

        return x.reshape(-1) #x / (x.abs().max() + 1e-7)


class EncodecModel(nn.Module):

    def __init__(self):

        super().__init__()
        self.decoder = SEANetDecoder()
        self.quantizer = ResidualVectorQuantizer()
        self.frame_rate = 50


    def decode(self, codes):
        # B,K,T -> B,C,T
        emb = self.quantizer.decode(codes)
        return self.decoder(emb)


class StreamableLSTM(nn.Module):

    def __init__(self,
                 dimension,
                 num_layers=2,
                 skip=True):
        
        super().__init__()
        self.skip = skip
        self.lstm = nn.LSTM(dimension, dimension, num_layers)

    def forward(self, x):
        x = x.permute(2, 0, 1)
        y, _ = self.lstm(x)
        if self.skip:
            y = y + x
        y = y.permute(1, 2, 0)
        return y



class SEANetResnetBlock(nn.Module):

    def __init__(self,
                 dim,
                 kernel_sizes = [3, 1], 
                 pad_mode = 'reflect', 
                 compress = 2):
        
        super().__init__()

        hidden = dim // compress
        block = []
        for i, kernel_size in enumerate(kernel_sizes):
            in_chs = dim if i == 0 else hidden
            out_chs = dim if i == len(kernel_sizes) - 1 else hidden
            block += [nn.ELU(),
                      StreamableConv1d(in_chs,
                                       out_chs,
                                       kernel_size=kernel_size,
                                       pad_mode=pad_mode)]
        self.block = nn.Sequential(*block)

    def forward(self, x):
        return x + self.block(x)





class SEANetDecoder(nn.Module):
#  channels=1 dimension=128 n_filters=64 n_residual_layers=1 ratios=[8, 5, 4, 2] 
# activation='ELU' activation_params={'alpha': 1.0}, final_activation=None
# final_activation_params=None norm='weight_norm' 
# norm_params={} kernel_size=7 last_kernel_size=7 residual_kernel_size=3 dilation_base=2 
# causal=False pad_mode='constant' 
# true_skip=True compress=2 lstm=2 disable_norm_outer_blocks=0 trim_right_ratio=1.0 

    def __init__(self,
                 channels = 1,
                 dimension = 128,
                 n_filters = 64,
                 n_residual_layers = 1,
                 ratios = [8, 5, 4, 2], 
                 kernel_size = 7,
                 last_kernel_size = 7, 
                 residual_kernel_size = 3, 
                 pad_mode = 'constant', 
                 compress = 2,
                 lstm = 2):
        
        super().__init__()


        mult = int(2 ** len(ratios))
        model = [
            StreamableConv1d(dimension, mult * n_filters,
                             kernel_size,
                             pad_mode=pad_mode)
        ]

        if lstm:
            print('\n\n\n\nLSTM IN SEANET\n\n\n\n')
            model += [StreamableLSTM(mult * n_filters,
                                     num_layers=lstm)]

        # Upsample to raw audio scale
        for i, ratio in enumerate(ratios):
            

            model += [
                nn.ELU(),
                StreamableConvTranspose1d(mult * n_filters,
                                          mult * n_filters // 2,
                                          kernel_size=ratio * 2,
                                          stride=ratio),
            ]
            # Add residual layers
            for j in range(n_residual_layers):

                model += [
                    SEANetResnetBlock(mult * n_filters // 2, 
                                      kernel_sizes=[residual_kernel_size, 1],
                                      pad_mode=pad_mode, 
                                      compress=compress)]

            mult //= 2
        
        # Add final layers
        model += [
            nn.ELU(),
            StreamableConv1d(n_filters,
                             channels,
                             last_kernel_size,
                             pad_mode=pad_mode)]
        self.model=nn.Sequential(*model)

    def forward(self, z):
        return self.model(z)




def unpad1d(x, paddings):
    padding_left, padding_right = paddings
    end = x.shape[-1] - padding_right
    return x[..., padding_left: end]


class NormConv1d(nn.Module):
    
    def __init__(self, *args, **kwargs):
        super().__init__()
        
        self.conv = weight_norm(nn.Conv1d(*args, **kwargs))  # norm = weight_norm
        
    def forward(self, x):
        return self.conv(x)





class NormConvTranspose1d(nn.Module):
    
    def __init__(self, *args, causal: bool = False, norm: str = 'none',
                 norm_kwargs = {}, **kwargs):
        super().__init__()
        
        self.convtr = weight_norm(nn.ConvTranspose1d(*args, **kwargs))
        
    def forward(self, x):
        return self.convtr(x)
        





class StreamableConv1d(nn.Module):

    def __init__(self,
                 in_channels, 
                 out_channels,
                 kernel_size, 
                 stride=1, 
                 groups=1, 
                 bias=True,
                 pad_mode='reflect'):
        super().__init__()
        if (stride != 1) or (groups != 1):
            raise ValueError
        self.conv = NormConv1d(in_channels,
                               out_channels,
                               kernel_size,
                               stride,
                               groups=groups,
                               bias=bias)
        self.pad_mode = pad_mode

    def forward(self, x):
        kernel_size = self.conv.conv.kernel_size[0]
        kernel_size = (kernel_size - 1) * self.conv.conv.dilation[0] + 1
        padding_total = kernel_size - self.conv.conv.stride[0]
        padding_right = padding_total // 2
        padding_left = padding_total - padding_right

        # x = pad1d(x, (padding_left, padding_right), mode=self.pad_mode)
        x = F.pad(x, (padding_left, padding_right), self.pad_mode)
        return self.conv(x)


class StreamableConvTranspose1d(nn.Module):

    def __init__(self, in_channels: int, out_channels: int,
                 kernel_size: int, stride: int = 1, causal: bool = False,
                 norm: str = 'none', trim_right_ratio: float = 1.,
                 norm_kwargs = {}):
        super().__init__()
        self.convtr = NormConvTranspose1d(in_channels,
                                          out_channels,
                                          kernel_size,
                                          stride)
        

    def forward(self, x):

        padding_total = self.convtr.convtr.kernel_size[0] - self.convtr.convtr.stride[0]

        y = self.convtr(x)

        # Asymmetric padding required for odd strides
        # print('\n   \n\n\nn\n\n\nnANTICAUSAL T\n\n\n')
        padding_right = padding_total // 2
        padding_left = padding_total - padding_right

        y = unpad1d(y, (padding_left, padding_right))
        return y


# VQ

class EuclideanCodebook(nn.Module):
    def __init__(self,
                 dim,
                 codebook_size):
        super().__init__()
        self.register_buffer("embed", torch.zeros(codebook_size, dim))




class VectorQuantization(nn.Module):
    
    def __init__(self,
                 dim,
                 codebook_size):
        
        super().__init__()
        self._codebook = EuclideanCodebook(dim=dim,
                                           codebook_size=codebook_size)

    def decode(self, _ind):
        return F.embedding(_ind, self._codebook.embed)


class ResidualVectorQuantization(nn.Module):

    def __init__(self, *, num_quantizers, **kwargs):
        super().__init__()
        self.layers = nn.ModuleList(
            [VectorQuantization(**kwargs) for _ in range(num_quantizers)]
        )

    def decode(self, _ind):
        x = 0.0
        for i, _code in enumerate(_ind):
            x = x + self.layers[i].decode(_code)
        return x.transpose(1, 2)


class ResidualVectorQuantizer(nn.Module):
    
# dimension=128 n_q=4 q_dropout=False bins=2048 decay=0.99 kmeans_init=True 
# kmeans_iters=50 threshold_ema_dead_code=2
# orthogonal_reg_weight=0.0 orthogonal_reg_active_codes_only=False 
# orthogonal_reg_max_codes=None

    def __init__(
        self,
        dimension = 128,
        n_q = 4,
        bins = 2048
        ):
        
        super().__init__()
        self.vq = ResidualVectorQuantization(dim=dimension,
                                             codebook_size=bins,
                                             num_quantizers=n_q)

    def decode(self, codes):
        # codes is [B, K, T], with T frames, K nb of codebooks, vq.decode expects [K, B, T].
        return self.vq.decode(codes.transpose(0, 1))    


class T5(nn.Module):

    def __init__(self):

        super().__init__()
        self.output_proj = nn.Linear(1024,  # t5-large
                                     1536)  # lm hidden
        self.t5_tokenizer = T5Tokenizer.from_pretrained('t5-large', legacy=True)
        t5 = T5EncoderModel.from_pretrained('t5-large').train(mode=False)

        # this makes sure that the t5 is not part
        # of the saved checkpoint
        self.__dict__['t5'] = t5.to('cpu')

    def forward(self, prompt):
        with torch.set_grad_enabled(False): #, torch.autocast(device_type='cpu', dtype=torch.float32):

            bs = len(prompt) // 2
            d = self.t5_tokenizer(prompt,
                                    return_tensors='pt',
                                    padding=True).to(self.output_proj.bias.device)
            d['attention_mask'][bs:, :] = 0  # null condition t5 attn_mask should be zero

            x = self.t5(input_ids=d['input_ids'],
                            attention_mask=d['attention_mask']).last_hidden_state  # no kv
        # Float 16
        # > self.output_proj() is outside of autocast of t5 - however inside the autocast of lm thus computed in torch.float16
        x = self.output_proj(x)  # nn.Linear() - produces different result if there is no duplicate txt condition here
        x[bs:, :, :] = 0  # venv/../site-packages/audiocraft/modules/conditioners.py -> tokenize()
        return x


class LMModel(nn.Module):

    def __init__(self,
                 n_q = 4,
                 card = 2048,
                 dim = 1536
                 ):
        super().__init__()
        self.cache_lim = -1
        self.t5 = T5()
        self.card = card # 2048
        self.n_draw = 1  # draw > 1 tokens of different CFG scale
                         # batch size > 1 is slower from n_draw as calls transformer on larger batch
        self.emb = nn.ModuleList([nn.Embedding(self.card + 1, dim) for _ in range(n_q)])  # EMBEDDING HAS 2049
        self.transformer = StreamingTransformer()
        self.out_norm = nn.LayerNorm(dim, eps=1e-5)
        self.linears = nn.ModuleList([nn.Linear(dim, self.card, bias=False) for _ in range(n_q)])  # LINEAR DOESNT HAVE 2049

    def forward(self,
                sequence,
                condition_tensors=None,
                cache_position=None
                ):

        bs, n_q, time_frames = sequence.shape # [bs, 4, time]

        input_ = sum([self.emb[k](sequence[:, k]) for k in range(n_q)])

        out = self.transformer(torch.cat([input_, input_], 0),  # duplicate null condition (bs x 2) for ClassifierFreeGuidance
                               cross_attention_src=condition_tensors,
                               cache_position=cache_position)

        out = self.out_norm(out)

        logits = torch.stack([self.linears[k](out) for k in range(n_q)], dim=1) # [2*bs, 4, 1,      2048]
        logits = 3 * logits[:bs, :, :, :] - self._scale * logits[bs:, :, :, :]                 # [  bs, 4, n_draw, 2048]

        #bs, n_q, n_draw, vocab = logits.shape
        tokens = torch.multinomial(torch.softmax(logits.view(bs * self.n_draw * n_q, 2048), dim=1),
                                   num_samples=1)
        return tokens.view(bs, n_q, self.n_draw).transpose(1, 2)

    @torch.no_grad()
    def generate(self,
                 max_tokens=None,
                 text_condition=None
                 ):
        x = self.t5(text_condition)
        bs = x.shape[0] // 2  # has null conditions - bs*2*N_REPEAT applys in builders.py
        self._scale = .3 * torch.rand(1, 1, self.n_draw, 1, device=x.device) + 1.94
        cache_position = 0

        out_codes = torch.full((bs,
                                self.n_draw,
                                4,
                                4 + 3 + max_tokens),  # 4 + max_tokens + 4-1 to have sufficient to index the 1st antidiagonal of 4x4 + 4 xtra tokens
                               self.card,
                               dtype=torch.long,
                               device=x.device) # [bs, n_draw, 4, dur]

        # A/R
        for offset in range(0, max_tokens + 4 - 1):  # max_tokens + n_q - 1

            # extract diagonal via indexing out_codes[ [0, 1, 2, 3], [0, 1, 2, 3] ]
            next_token = self.forward(out_codes[:, 0, [0, 1, 2, 3], torch.tensor([3, 2, 1, 0]) + offset][:, :, None],  # index diagonal & exapnd to [bs, n_q, dur=1]
                                      #gen_sequence[:, 0, :, offset-1:offset],  # DIAGINDEXING for setting prediction of lm into gen_sequence THE GENSEQUENCE has to be un-delayed in the end [Because it has to be de-delayed for the vocoder then is actually only the lm input that requires to see the delay thus we could just feed by diaggather] so it matches gen_codes -1 a[[0, 1, 2, 3], torch.tensor([0, 1, 2, 3]) + 5]  the gen_sequence is indexed by vertical column and fed to lm however the prediction of lm is place diagonally with delay to the gen_sequence
                                      condition_tensors=x,  # utilisation of the attention mask of txt condition ?
                                      cache_position=cache_position)  # [bs, n_draw, 4]

            # Fill of next_token should be also placed on antidiagonal [not column]

            #   Do Not Overwrite 2048 of TRIU/TRIL = START/END => Do Not Fill them by Predicted Tokens
            # 0-th antidiagonal should be full of card = [2048, 2048, 2048, 2048]
            #
            #   [2048, 2048, 2048, 2048,    0,    1,    2,    3,    4,    5,    6, 2048, 2048, 2048],
            #   [2048, 2048, 2048, 2048, 2048,    0,    1,    2,    3,    4,    5,    6, 2048, 2048],
            #   [2048, 2048, 2048, 2048, 2048, 2048,    0,    1,    2,    3,    4,    5,    6, 2048],
            #   [2048, 2048, 2048, 2048, 2048, 2048, 2048,    0,    1,    2,    3,    4,    5,    6]]
            # NO OVerWriting
            if offset == 0:

                next_token[:, :, 1:4] = 2048  # self.card - bottom 3 entries of the antidiagonal should remain 2048

            elif offset == 1:

                next_token[:, :, 2:4] = 2048  # bottom 2 entries of the antidiagonal should remain 2048

            elif offset == 2:

                next_token[:, :, 3:4] = 2048

            elif offset == max_tokens:

                next_token[:, :, 0:1] = 2048  # top 1 entry of the antidiagonal should stay to 2048

            elif offset == (max_tokens + 1):

                next_token[:, :, 0:2] = 2048

            elif offset == (max_tokens + 2):

                next_token[:, :, 0:3] = 2048

            else:  # offset 3,4,5,6,7...... max_tokens-1   # FILL Complete n_q = 4 ANTIDIAGONAL ENTRIES

                pass #print('No delete anti-diag')

            out_codes[:, :, [0, 1, 2, 3], torch.tensor([3, 2, 1, 0]) + offset + 1] = next_token
            # Sink Attn
            if (offset > 0) and (offset % self.cache_lim) == 0:
                n_preserve = 4
                self.transformer._flush(n_preserve=n_preserve)
                cache_position = n_preserve
            else:
                cache_position += 1

        # [bs, n_draw, 4, time+xtra] -> [bs, 4, n_draw, time] ->  [bs, 4, time * n_draw]
        out_codes = out_codes[:, :, :, 4:max_tokens+4].transpose(1, 2).reshape(bs, 4, self.n_draw * max_tokens)

        # flush for next API call
        self.transformer._flush()

        return out_codes  # SKIP THE 4 fill 2048




def create_sin_embedding(positions,
                         dim,
                         max_period=10000
                         ):
    # assert dim % 2 == 0
    half_dim = dim // 2
    positions = positions.to(torch.float)
    adim = torch.arange(half_dim, device=positions.device,
                        dtype=torch.float).view(1, 1, -1)
    max_period_tensor = torch.full([],
                                   max_period,
                                   device=positions.device,
                                   dtype=torch.float)  # avoid sync point
    phase = positions / (max_period_tensor ** (adim / (half_dim - 1)))
    # OFFICIAL is torch.float32 HOWEVER self_attn.in_prod_weight = torch.float16
    return torch.cat([torch.cos(phase), torch.sin(phase)], dim=-1)


class StreamingMultiheadAttention(nn.Module):

    def __init__(self,
                 embed_dim,
                 num_heads,
                 cross_attention=False,
                 ):

        super().__init__()

        self.cross_attention = cross_attention
        # if not self.cross_attention then it has kvcachingn
        self.k_history = None
        # cleanup history through LM inside GENERATION - Each 0,..,47 mha has different kv history
        self.v_history = None
        self.num_heads = num_heads
        self.out_proj = nn.Linear(embed_dim, embed_dim, bias=False)
        self.register_buffer('in_proj_weight', torch.ones((3 * embed_dim, embed_dim),
                                                          dtype=torch.float))

    def forward(self,
                query,
                key=None,
                value=None):
        layout = "b h t d"
        if self.cross_attention:

            # Different queries, keys, values > split in_proj_weight

            dim = self.in_proj_weight.shape[0] // 3

            q = nn.functional.linear(query, self.in_proj_weight[:dim])
            k = nn.functional.linear(key,   self.in_proj_weight[dim: 2 * dim])
            v = nn.functional.linear(value, self.in_proj_weight[2 * dim:])

            q, k, v = [
                rearrange(x, f"b t (h d) -> {layout}", h=self.num_heads) for x in [q, k, v]]

        else:

            # Here <else> = self_attention for audio with itself (above is cross attention txt)

            # HISTORY - DIFFERENT FOR EACH TRANSF LAYER

            # here we have different floating values from official
            projected = nn.functional.linear(query, self.in_proj_weight, None)
            # print(query.sum(), projected.sum() , self.in_proj_weight.sum(), 'Lc')   # verified official AudioGen values
            bound_layout = "b h p t d"
            packed = rearrange(
                projected, f"b t (p h d) -> {bound_layout}", p=3, h=self.num_heads)
            q, k, v = packed.unbind(dim=2)
            if self.k_history is not None:
                # IF ctrl^c during live_demo the assigning of each of kv is non-atomic k!=v
                # thus it will try to continue with incompatible k/v dims!
                self.k_history = torch.cat([self.k_history, k], 2)
                self.v_history = torch.cat([self.v_history, v], 2)
            else:
                self.k_history = k
                self.v_history = v

            # Assign Completed k / v to k / v

            k = self.k_history
            v = self.v_history

            # -> kv CACHE ONLY APPLIES if not self.cross_attention

        x = torch.nn.functional.scaled_dot_product_attention(
            q, k, v, attn_mask=None, is_causal=False, dropout_p=0.0)

        x = rearrange(x, f"{layout} -> b t (h d)", h=self.num_heads)
        x = self.out_proj(x)
        return x


class StreamingTransformerLayer(nn.Module):

    def __init__(self,
                 d_model,
                 num_heads,
                 dim_feedforward):
        
        super().__init__()

        self.self_attn = StreamingMultiheadAttention(embed_dim=d_model,
                                                     num_heads=num_heads)
        self.linear1 = nn.Linear(d_model, dim_feedforward, bias=False)
        self.linear2 = nn.Linear(dim_feedforward, d_model, bias=False)
        self.cross_attention = StreamingMultiheadAttention(embed_dim=d_model,
                                                           num_heads=num_heads,
                                                           cross_attention=True)
        self.norm_cross = nn.LayerNorm(d_model, eps=1e-5)
        self.norm1 = nn.LayerNorm(d_model, eps=1e-5)
        self.norm2 = nn.LayerNorm(d_model, eps=1e-5)

    def forward(self,
                x,
                cross_attention_src=None):
        x = x + self.self_attn(self.norm1(x))
        x = x + self.cross_attention(query=self.norm_cross(x),
                                     key=cross_attention_src,
                                     value=cross_attention_src)  # txtcondition
        x = x + self.linear2(F.gelu(self.linear1(self.norm2(x))))
        return x


class StreamingTransformer(nn.Module):

    def __init__(self,
                 d_model=1536,
                 num_heads=24,
                 num_layers=48,
                 dim_feedforward=6144):
        super().__init__()

        self.layers = nn.ModuleList(
                [
                    StreamingTransformerLayer(d_model=d_model,
                                              num_heads=num_heads,
                                              dim_feedforward=dim_feedforward) for _ in range(num_layers)
                    ]
                )

    def forward(self,
                x,
                cache_position=None,
                cross_attention_src=None):

        x = x + create_sin_embedding(
                torch.zeros(x.shape[0], 1, 1, device=x.device) + cache_position, 1536)

        for lay in self.layers:
            x = lay(x,
                    cross_attention_src=cross_attention_src)
        return x

    def _flush(self,
               n_preserve=None):

        for lay in self.layers:
            if n_preserve is not None:
                # cache position is difficult to choose to also preserve kv from end
                lay.self_attn.k_history = lay.self_attn.k_history[:, :, :n_preserve, :]
                lay.self_attn.v_history = lay.self_attn.v_history[:, :, :n_preserve, :]
            else:
                lay.self_attn.k_history = None
                lay.self_attn.v_history = None


if __name__ == '__main__':

    import audiofile
    model = AudioGen().to('cpu')
    x = model.generate(prompt='swims in lake frogs', duration=6.4).cpu().numpy()
    audiofile.write('_sound_.wav', x, 16000)