# coding=utf-8
# Copyright 2024 the HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
""" PyTorch Llava-NeXT model."""
from typing import List, Optional, Tuple
import torch
import torch.utils.checkpoint
from torch import nn
from transformers.activations import ACT2FN
from transformers.image_processing_utils import select_best_resolution
from text_generation_server.layers.attention import Seqlen
from text_generation_server.models.custom_modeling.vlm import (
load_text_model,
load_vision_model,
)
from text_generation_server.layers import (
TensorParallelColumnLinear,
TensorParallelRowLinear,
)
def get_anyres_image_grid_shape(image_size, grid_pinpoints, patch_size):
"""
Calculate the shape of the image patch grid after the preprocessing for images of any resolution.
Args:
image_size (`tuple`):
The size of the input image in the format (height, width).
grid_pinpoints (`List`):
A list containing possible resolutions. Each item in the list should be a tuple or list
of the form `(height, width)`.
patch_size (`int`):
The size of each image patch.
Returns:
tuple: The shape of the image patch grid in the format (height, width).
"""
if not isinstance(grid_pinpoints, list):
raise ValueError("grid_pinpoints should be a list of tuples or lists")
height, width = select_best_resolution(image_size, grid_pinpoints)
return height // patch_size, width // patch_size
def unpad_image(tensor, original_size):
"""
Unpads a PyTorch tensor of a padded and resized image.
Args:
tensor (`torch.Tensor`):
The image tensor, assumed to be of shape (num_channels, height, width).
original_size (`tuple`):
The original size of the image (height, width).
Returns:
`torch.Tensor`: The unpadded image tensor.
"""
original_height, original_width = original_size
current_height, current_width = tensor.shape[1:]
original_aspect_ratio = original_width / original_height
current_aspect_ratio = current_width / current_height
if original_aspect_ratio > current_aspect_ratio:
scale_factor = current_width / original_width
new_height = int(original_height * scale_factor)
padding = (current_height - new_height) // 2
unpadded_tensor = tensor[:, padding : current_height - padding, :]
else:
scale_factor = current_height / original_height
new_width = int(original_width * scale_factor)
padding = (current_width - new_width) // 2
unpadded_tensor = tensor[:, :, padding : current_width - padding]
return unpadded_tensor
# Copied from transformers.models.llava.modeling_llava.LlavaMultiModalProjector with Llava->LlavaNext
class LlavaNextMultiModalProjector(nn.Module):
def __init__(self, prefix, config, weights):
super().__init__()
self.linear_1 = TensorParallelColumnLinear.load(
prefix=f"{prefix}.linear_1", config=config, weights=weights, bias=True
)
self.act = ACT2FN[config.projector_hidden_act]
self.linear_2 = TensorParallelRowLinear.load(
prefix=f"{prefix}.linear_2", config=config, weights=weights, bias=True
)
def forward(self, image_features):
hidden_states = self.linear_1(image_features)
hidden_states = self.act(hidden_states)
hidden_states = self.linear_2(hidden_states)
return hidden_states
class LlavaNextForConditionalGeneration(nn.Module):
def __init__(self, prefix, config, weights):
super().__init__()
config.vision_config.quantize = config.quantize
vision_config = config.vision_config
# Instead of selecting in hidden_states[-2].
# Instead compute only the n -2 + 1 layers and don't pool
if config.vision_feature_layer < 0:
vision_config.num_hidden_layers += config.vision_feature_layer + 1
else:
vision_config.num_hidden_layers = config.vision_feature_layer + 1
self.vision_tower = load_vision_model(
prefix="vision_tower" if not prefix else f"{prefix}.vision_tower",
config=config.vision_config,
weights=weights,
)
self.multi_modal_projector = LlavaNextMultiModalProjector(
prefix="multi_modal_projector", config=config, weights=weights
)
self.image_newline = weights.get_tensor("image_newline")
self.vocab_size = config.text_config.vocab_size
self.config = config
config.text_config.quantize = config.quantize
config.text_config.speculator = config.speculator
self.text_model = load_text_model(
prefix="language_model" if not prefix else f"{prefix}.language_model",
config=config.text_config,
weights=weights,
)
self.pad_token_id = (
config.pad_token_id if config.pad_token_id is not None else -1
)
def _merge_input_ids_with_image_features(
self,
input_ids: torch.Tensor,
inputs_embeds: torch.Tensor,
image_features: torch.Tensor,
):
"""In place merges in vision_embeddings with inputs_embeds."""
mask = input_ids == self.config.image_token_index
# Let's pray we have enabled enough slots !
try:
inputs_embeds[mask] = image_features.view(-1, image_features.shape[-1])
except Exception as e:
raise RuntimeError(
f"Cannot fill images right now. If error happens at warmup, make sure you have enough `--max-input-tokens` to handle images. If error happens at regular runtime, please fill in an issue: {e}"
)
return inputs_embeds
def forward(
self,
input_ids: torch.Tensor,
position_ids: torch.Tensor,
cu_seqlen_prefill: Optional[torch.Tensor],
kv_cache: List[Tuple[torch.Tensor, torch.Tensor]],
block_tables: torch.Tensor,
slots: torch.Tensor,
seqlen: Seqlen,
max_s: int,
prefill_cache_indices: Optional[torch.Tensor],
lm_head_indices: Optional[torch.Tensor] = None,
pixel_values: torch.FloatTensor = None,
# Unused for this model
pixel_attention_mask=None,
image_sizes: Optional[torch.LongTensor] = None,
adapter_data: Optional[torch.Tensor] = None,
):
inputs_embeds = self.text_model.embed_tokens(input_ids)
if pixel_values is not None and len(pixel_values) > 0:
# num_special_image_tokens = (input_ids == self.config.image_token_index).sum()
# assert num_special_image_tokens == len(pixel_values), f"Received {num_special_image_tokens} for {len(pixel_values)} images, this is invalid"
# 1. Extract the input embeddings
# 2. Merge text and images
num_images, num_patches, channels, height, width = pixel_values.shape
pixel_values = pixel_values.view(
num_images * num_patches, channels, height, width
)
image_features = self.vision_tower(pixel_values)
# selected_image_feature = image_features.hidden_states[self.config.vision_feature_layer]
# Already done within the clip model
selected_image_feature = image_features.last_hidden_state
if self.config.vision_feature_select_strategy == "default":
selected_image_feature = selected_image_feature[:, 1:]
elif self.config.vision_feature_select_strategy == "full":
selected_image_feature = selected_image_feature
else:
raise RuntimeError(
f"Strategy `{self.config.vision_feature_select_strategy}` is not supported/valid."
)
image_features = self.multi_modal_projector(selected_image_feature)
# split up image_features for each of the individual images
# hence we get a list of image_features, each of shape (5, num_patches, hidden_size)
# if we assume each image has 5 image features (base image + 4 patches)
split_sizes = [num_patches] * num_images
image_features = torch.split(image_features, split_sizes, dim=0)
# NOTE we only support multimodal_patch_merge_type == "spatial_unpad"
height = width = (
self.config.vision_config.image_size
// self.config.vision_config.patch_size
)
new_image_features = []
for image_idx, image_feature in enumerate(image_features):
if image_feature.shape[0] > 1:
base_image_feature = image_feature[0]
image_feature = image_feature[1:]
if height * width != base_image_feature.shape[0]:
raise ValueError(
"The number of patches is not consistent with the image size."
)
# Dimensions are intentionally swapped to be bug-compatible with
# upstream: https://github.com/LLaVA-VL/LLaVA-NeXT/issues/59
num_patch_width, num_patch_height = get_anyres_image_grid_shape(
image_sizes[image_idx],
self.config.image_grid_pinpoints,
self.config.vision_config.image_size,
)
image_feature = image_feature.view(
num_patch_height, num_patch_width, height, width, -1
)
image_feature = image_feature.permute(4, 0, 2, 1, 3).contiguous()
image_feature = image_feature.flatten(1, 2).flatten(2, 3)
image_feature = unpad_image(image_feature, image_sizes[image_idx])
image_feature = torch.cat(
(
image_feature,
self.image_newline[:, None, None].expand(
*image_feature.shape[:-1], 1
),
),
dim=-1,
)
image_feature = image_feature.flatten(1, 2).transpose(0, 1)
image_feature = torch.cat(
(base_image_feature, image_feature), dim=0
)
else:
image_feature = image_feature[0]
image_feature = torch.cat(
(image_feature, self.image_newline[None]), dim=0
)
new_image_features.append(image_feature)
image_features = torch.stack(new_image_features, dim=0)
inputs_embeds = self._merge_input_ids_with_image_features(
input_ids, inputs_embeds, image_features
)
hidden_states = self.text_model.model(
inputs_embeds=inputs_embeds,
position_ids=position_ids,
cu_seqlen_prefill=cu_seqlen_prefill,
kv_cache=kv_cache,
block_tables=block_tables,
slots=slots,
seqlen=seqlen,
max_s=max_s,
true_max_s=max_s,
prefill_cache_indices=None,
adapter_data=adapter_data,
)
if lm_head_indices is not None:
hidden_states = hidden_states[lm_head_indices]
logits, speculative_logits = self.text_model.lm_head(hidden_states)
return logits, speculative_logits