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Upload ./inference_utils.py with huggingface_hub

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  1. inference_utils.py +154 -0
inference_utils.py ADDED
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+ import torch
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+ import torchaudio
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+ import torch.nn.functional as F
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+ from typing import Optional, List, Tuple
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+ from tqdm import tqdm
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+
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+
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+ def apply_top_k(logits, top_k):
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+ batch_size, vocab_size = logits.shape
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+ top_k = min(top_k, vocab_size)
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+ top_k_values, top_k_indices = torch.topk(logits, top_k, dim=-1)
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+ filtered_logits = torch.full_like(logits, float("-inf"))
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+ batch_indices = torch.arange(batch_size).unsqueeze(-1)
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+ filtered_logits[batch_indices, top_k_indices] = top_k_values
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+ return filtered_logits
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+
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+
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+ def apply_top_p(logits, top_p):
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+ probs = F.softmax(logits, dim=-1)
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+ sorted_probs, sorted_indices = torch.sort(probs, descending=True, dim=-1)
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+ cumulative_probs = torch.cumsum(sorted_probs, dim=-1)
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+ sorted_indices_to_remove = cumulative_probs > top_p
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+ sorted_indices_to_remove[..., 1:] = sorted_indices_to_remove[..., :-1].clone()
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+ sorted_indices_to_remove[..., 0] = False
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+ batch_size = logits.shape[0]
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+ filtered_logits = logits.clone()
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+ for i in range(batch_size):
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+ indices_to_remove = sorted_indices[i][sorted_indices_to_remove[i]]
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+ filtered_logits[i, indices_to_remove] = float("-inf")
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+ return filtered_logits
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+
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+
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+ def apply_top_p_optimized(logits, top_p):
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+ probs = F.softmax(logits, dim=-1)
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+ sorted_probs, sorted_indices = torch.sort(probs, descending=True, dim=-1)
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+
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+ cumulative_probs = torch.cumsum(sorted_probs, dim=-1)
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+
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+ sorted_indices_to_remove = cumulative_probs > top_p
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+ sorted_indices_to_remove[..., 1:] = sorted_indices_to_remove[..., :-1].clone()
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+ sorted_indices_to_remove[..., 0] = False
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+
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+ indices_to_remove = torch.zeros_like(logits, dtype=torch.bool).scatter_(
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+ dim=-1, index=sorted_indices, src=sorted_indices_to_remove
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+ )
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+
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+ logits[indices_to_remove] = float("-inf")
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+ return logits
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+
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+
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+ def apply_repetition_penalty_delay_pattern(
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+ logits: torch.Tensor,
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+ prev_tokens: torch.LongTensor,
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+ penalty: float,
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+ ):
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+ """
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+ logits: [B, H, V] or [N, V]
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+ prev_tokens: [B, T, H] or [N, T] or [B, H]
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+
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+ Apply the repetition penalty independently for each H (VQ head).
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+ """
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+ if penalty == 1.0 or prev_tokens is None:
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+ return logits
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+
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+ vocab_size = logits.size(-1)
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+
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+ # Case 1: regular [N, V] (text layer)
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+ if logits.dim() == 2:
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+ prev_tokens_flat = prev_tokens.reshape(-1)
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+ unique_tokens = torch.unique(prev_tokens_flat)
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+
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+ token_logits = logits[:, unique_tokens]
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+ pos_mask = token_logits > 0
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+ token_logits[pos_mask] /= penalty
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+ token_logits[~pos_mask] *= penalty
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+ logits[:, unique_tokens] = token_logits
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+ return logits
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+
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+ # Case 2: Delay Pattern audio [B, H, V]
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+ assert logits.dim() == 3, "Delay Pattern audio logits must be [B, H, V]"
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+ B, H, V = logits.shape
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+
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+ for h in range(H):
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+ # prev_tokens_h: [B, T] or [B]
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+ prev_tokens_h = prev_tokens[..., h].reshape(-1)
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+ unique_tokens = torch.unique(prev_tokens_h)
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+
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+ if unique_tokens.numel() == 0:
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+ continue
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+
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+ token_logits = logits[:, h, unique_tokens]
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+ pos_mask = token_logits > 0
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+ token_logits[pos_mask] /= penalty
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+ token_logits[~pos_mask] *= penalty
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+ logits[:, h, unique_tokens] = token_logits
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+
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+ return logits
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+
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+
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+ def sample_token(
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+ logits,
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+ prev_tokens: Optional[torch.LongTensor] = None,
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+ repetition_penalty: float = 1.0,
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+ top_p=None,
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+ top_k=None,
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+ do_sample=True,
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+ ):
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+ vocab_size = logits.size(-1)
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+
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+ # ===== Repetition Penalty (before reshaping!) =====
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+ if prev_tokens is not None and repetition_penalty != 1.0:
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+ logits = apply_repetition_penalty_delay_pattern(
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+ logits,
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+ prev_tokens,
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+ repetition_penalty,
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+ )
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+
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+ if not do_sample:
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+ return torch.argmax(logits, dim=-1)
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+
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+ # ===== Only flatten after this, for top-k / top-p / multinomial =====
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+ original_shape = logits.shape
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+ reshaped_logits = logits.view(-1, vocab_size)
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+
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+ if top_k is not None and top_k > 0:
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+ reshaped_logits = apply_top_k(reshaped_logits, top_k)
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+
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+ if top_p is not None and top_p < 1.0:
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+ reshaped_logits = apply_top_p_optimized(reshaped_logits, top_p)
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+
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+ probs = F.softmax(reshaped_logits, dim=-1)
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+ next_tokens = torch.multinomial(probs, num_samples=1)
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+
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+ return next_tokens.view(original_shape[:-1])
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+
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+
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+ def find_last_equal_C(tensor, C):
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+ """
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+ tensor: torch.Tensor of shape [batch_size, seq_len]
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+ C: scalar value to match
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+ Returns: torch.Tensor of shape [batch_size] with last indices
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+ """
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+ mask = (tensor == C).int() # Shape: [batch_size, seq_len], bool tensor
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+ flipped_mask = mask.flip(dims=[1]) # Flip along sequence dimension
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+ flipped_indices = flipped_mask.argmax(dim=1) # First True in flipped
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+ seq_len = tensor.shape[1]
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+ last_indices = (seq_len - 1) - flipped_indices # Convert to original indices
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+
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+ # Optional: Handle cases with no C (set to -1), though problem assumes existence
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+ actual_values = tensor[torch.arange(tensor.shape[0]), last_indices]
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+ no_match = actual_values != C
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+ last_indices[no_match] = -1
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+
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+ return last_indices