mtmd: Add Gemma3n multimodal support with MobileNetV5 vision encoder (#18256)

* Add Gemma3nVisionModel - MobileNetV5 vision encoder convertor to convert_hf_to_gguf.py. Add gemma3n to vision projectors in gguf-py/gguf/constants.py.

* Add mobilenetv5 impl

* Fix comments, remove unused vars

* Fix permute and remove transpose of projection weights

* Fix comments, remove debugging prints from hf_to_gguf

* 1. Hard-code image_mean = 0 and image_std = 1
2. Use available tensor mapping logic
3. Remove redundant chat template replacement of soft tokens placeholder with media placeholder

* 1. Move mobilenetv5 helpers declarations to `clip_graph_mobilenetv5` struct and definitions to mobilenetv5.cpp
2.Remove unused `clip_is_gemma3n` func declarations and definitions
3. Remove redundant `rescale_image_u8_to_f32` func and use `normalize_image_u8_to_f32` with zero mean and unit std
4. Calculate n_patches using image_size / patch_size

* Remove obsolete comments

* - convert_hf_to_gguf.py & constants.py & tensor_mapping.py: Use explicit mapping: Custom map for double indexed blocks and tensor_mapping.py for rest
- convert_hf_to_gguf.py: Unsqueeze Stem Bias and Layer scale tensors to correct shape while converting to gguf
- mobilenetv5.cpp: Remove explicit reshaping of Stem Bias and Layer scale which are now handled while converting to gguf, replace fprintf with LOG_*
- clip.cpp: Remove unused embedding and hard_emb_norm tensor loading

* - Rename tensors to v.conv..., v.blk..., v.msfa... to better align with already existing terminology

* Fix stem conv bias name

* Remove explicit handling of bias term for stem conv

* - Change order of addition in "project_per_layer_inputs" to support broadcasting of vision inp_per_layer
- Simplify the vision embeddings path of "get_per_layer_inputs" to output [n_embd_altup, n_layer, 1], broadcastable

* clean up conversion script

* fix code style

* also preserve audio tensors

* trailing space

* split arch A and V

* rm unused gemma3 func

* fix alignment

---------

Co-authored-by: Xuan Son Nguyen <son@huggingface.co>
This commit is contained in:
Simranjeet Singh
2026-01-09 23:42:38 +01:00
committed by GitHub
co-authored by Xuan Son Nguyen
parent 593da7fa49
commit a61c8bc3bf
13 changed files with 1178 additions and 99 deletions
+218 -48
View File
@@ -528,7 +528,11 @@ class ModelBase:
return ()
def prepare_tensors(self):
max_name_len = max(len(s) for _, s in self.tensor_map.mapping.values()) + len(".weight,")
# Handle empty tensor_map for models with block_count=0 (like MobileNetV5)
if self.tensor_map.mapping:
max_name_len = max(len(s) for _, s in self.tensor_map.mapping.values()) + len(".weight,")
else:
max_name_len = len("vision_encoder.weight,") # Default reasonable length
for name, data_torch in chain(self.generate_extra_tensors(), self.get_tensors()):
# we don't need these
@@ -6038,7 +6042,175 @@ class Gemma3VisionModel(MmprojModel):
return [] # skip other tensors
class ConformerAudioModel(MmprojModel):
_batch_norm_tensors: list[dict[str, Tensor]] | None = None
@staticmethod
def is_audio_tensor(name: str):
return any(p in name for p in ["audio", "codebook", "conformer", "depth_embedding", "depthformer", "depth_linear"])
def tensor_force_quant(self, name, new_name, bid, n_dims):
if ConformerAudioModel.is_audio_tensor(name):
if ".conv" in name or "_conv" in name and ".weight" in name:
return gguf.GGMLQuantizationType.F32
return super().tensor_force_quant(name, new_name, bid, n_dims)
def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iterable[tuple[str, Tensor]]:
# fold running_mean, running_var and eps into weight and bias for batch_norm
if "batch_norm" in name:
if self._batch_norm_tensors is None:
self._batch_norm_tensors = [{} for _ in range(self.block_count)]
assert bid is not None
self._batch_norm_tensors[bid][name] = data_torch
if len(self._batch_norm_tensors[bid]) < 5:
return []
weight = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.weight"]
bias = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.bias"]
running_mean = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.running_mean"]
running_var = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.running_var"]
eps = 1e-5 # default value
a = weight / torch.sqrt(running_var + eps)
b = bias - running_mean * a
return [
(self.map_tensor_name(f"conformer.layers.{bid}.conv.batch_norm.weight"), a),
(self.map_tensor_name(f"conformer.layers.{bid}.conv.batch_norm.bias"), b),
]
# reshape conv weights
if name.startswith("conformer.pre_encode.conv.") and name.endswith(".bias"):
data_torch = data_torch[:, None, None]
if "conv.depthwise_conv" in name and name.endswith(".weight"):
assert data_torch.shape[1] == 1
data_torch = data_torch.reshape(data_torch.shape[0], data_torch.shape[2])
if "conv.pointwise_conv" in name and name.endswith(".weight"):
assert data_torch.shape[2] == 1
data_torch = data_torch.reshape(data_torch.shape[0], data_torch.shape[1])
return [(self.map_tensor_name(name), data_torch)]
@ModelBase.register("Gemma3nForConditionalGeneration")
class Gemma3nVisionAudioModel(ConformerAudioModel):
has_audio_encoder = True
has_vision_encoder = True
# Double indexed mapping for MobileNetV5 blocks (not supported by tensor_mapping.py)
# This is the only known model having this, so we prefer implementing it outside of tensor_mapping.py
block_tensor_mapping = {
"model.vision_tower.timm_model.blocks.{bid}.{sid}.conv_exp.weight": "v.blk.{bid}.{sid}.conv_exp.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.bn1.weight": "v.blk.{bid}.{sid}.bn1.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.conv_pwl.weight": "v.blk.{bid}.{sid}.conv_pwl.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.bn2.weight": "v.blk.{bid}.{sid}.bn2.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.dw_start.conv.weight": "v.blk.{bid}.{sid}.dw_start.conv.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.dw_start.bn.weight": "v.blk.{bid}.{sid}.dw_start.bn.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.dw_mid.conv.weight": "v.blk.{bid}.{sid}.dw_mid.conv.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.dw_mid.bn.weight": "v.blk.{bid}.{sid}.dw_mid.bn.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.pw_exp.conv.weight": "v.blk.{bid}.{sid}.pw_exp.conv.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.pw_exp.bn.weight": "v.blk.{bid}.{sid}.pw_exp.bn.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.pw_proj.conv.weight": "v.blk.{bid}.{sid}.pw_proj.conv.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.pw_proj.bn.weight": "v.blk.{bid}.{sid}.pw_proj.bn.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.layer_scale.gamma": "v.blk.{bid}.{sid}.layer_scale.gamma",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.query.proj.weight": "v.blk.{bid}.{sid}.attn.query.proj.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.key.proj.weight": "v.blk.{bid}.{sid}.attn.key.proj.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.value.proj.weight": "v.blk.{bid}.{sid}.attn.value.proj.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.output.proj.weight": "v.blk.{bid}.{sid}.attn.output.proj.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.key.down_conv.weight": "v.blk.{bid}.{sid}.attn.key.down_conv.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.key.norm.weight": "v.blk.{bid}.{sid}.attn.key.norm.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.value.down_conv.weight": "v.blk.{bid}.{sid}.attn.value.down_conv.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.attn.value.norm.weight": "v.blk.{bid}.{sid}.attn.value.norm.weight",
"model.vision_tower.timm_model.blocks.{bid}.{sid}.norm.weight": "v.blk.{bid}.{sid}.norm.weight",
}
def __init__(self, *args, **kwargs):
# Parent init will call find_hparam which now returns 0 for empty keys
super().__init__(*args, **kwargs)
assert self.hparams_vision is not None
self.hparams_vision["n_layers"] = 128 # fake value for audio encoder, vision encoder doesn't use it
self.hparams_vision["intermediate_size"] = self.hparams_vision.get("intermediate_size", 2048) * 4
self.hparams_vision["num_attention_heads"] = self.hparams_vision.get("num_attention_heads", 8)
# MobileNetV5 does not use image_mean/std
self.preprocessor_config["image_mean"] = [0.0 ,0.0 , 0.0]
self.preprocessor_config["image_std"] = [1.0 ,1.0 ,1.0]
self.hparams_vision["image_size"] = self.preprocessor_config.get(
"size", {"height": 768, "width": 768}
)["height"]
# Image sequence length (256 tokens = 16x16 for Gemma3n)
image_seq_length = self.preprocessor_config.get("image_seq_length", 256)
image_size = self.hparams_vision["image_size"]
self.hparams_vision["patch_size"] = image_size // image_seq_length
# remap audio hparams
assert self.hparams_audio is not None
self.hparams_audio["n_layers"] = self.hparams_audio["conf_num_hidden_layers"]
self.hparams_audio["num_attention_heads"] = self.hparams_audio["conf_num_attention_heads"]
self.hparams_audio["feat_in"] = self.hparams_audio["input_feat_size"]
self.hparams_audio["intermediate_size"] = self.hparams_audio.get("intermediate_size", 6144)
def set_gguf_parameters(self):
super().set_gguf_parameters()
# vision params
self.gguf_writer.add_clip_vision_projector_type(gguf.VisionProjectorType.GEMMA3NV)
self.gguf_writer.add_vision_attention_layernorm_eps(self.hparams.get("layer_norm_eps", 1e-6))
# audio params
assert self.hparams_audio is not None
self.gguf_writer.add_clip_audio_projector_type(gguf.VisionProjectorType.GEMMA3NA)
self.gguf_writer.add_audio_num_mel_bins(self.hparams_audio["feat_in"])
self.gguf_writer.add_audio_attention_layernorm_eps(1e-5)
def tensor_force_quant(self, name, new_name, bid, n_dims):
# Force quantization settings for specific tensor types
if "input_projection" in name or "input_proj" in name:
return gguf.GGMLQuantizationType.F16
if ".embeddings." in name or "stem" in name:
return gguf.GGMLQuantizationType.F32
return super().tensor_force_quant(name, new_name, bid, n_dims)
def custom_map(self, name: str) -> str:
"""Parses names like model.vision_tower.timm_model.blocks.1.2.suffix and applies template mapping."""
parts = name.split(".")
# MobileNet blocks have at least 7 parts: model, vision_tower, timm_model, blocks, bid, sid, and suffix
if len(parts) >= 7:
bid, sid = parts[4], parts[5]
suffix = ".".join(parts[6:])
template = f"model.vision_tower.timm_model.blocks.{{bid}}.{{sid}}.{suffix}"
if template in self.block_tensor_mapping:
return self.block_tensor_mapping[template].format(bid=bid, sid=sid)
raise ValueError(f"Unknown name: {name}")
def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iterable[tuple[str, Tensor]]:
if (ConformerAudioModel.is_audio_tensor(name)):
name = name.replace("model.audio_tower.conformer.", "conformer.layers.")
return super().modify_tensors(data_torch, name, bid)
# Gemma3n uses
# - model.embed_vision.* for projection layers
# - model.vision_tower.* for vision encoder
# Skip non-vision tensors
if not (name.startswith("model.embed_vision.") or name.startswith("model.vision_tower.")):
return []
if name.startswith("model.vision_tower.timm_model.blocks."):
# Double-indexed block tensors through custom logic
new_name = self.custom_map(name)
else:
# Route non-repeating (conv_stem, msfa, embedding, etc.) and un-catched through tensor_mapping.py
new_name = self.map_tensor_name(name)
if new_name.endswith("conv_stem.conv.bias") or new_name.endswith("layer_scale.gamma"):
data_torch = data_torch.unsqueeze(0).unsqueeze(-1).unsqueeze(-1) # [1, C, 1, 1]
return [(new_name, data_torch)]
@ModelBase.register("Gemma3nForCausalLM", "Gemma3nForConditionalGeneration")
class Gemma3NModel(Gemma3Model):
model_arch = gguf.MODEL_ARCH.GEMMA3N
norm_shift = 0.0 # same value with Gemma3p5RMSNorm scale_shift on python code
@@ -6061,8 +6233,25 @@ class Gemma3NModel(Gemma3Model):
]
def set_vocab(self):
# For Gemma3n multimodal models, we need the FULL vocab_size (262400)
# which includes special tokens from 262144-262399 for vision/audio.
# The vocab_size_per_layer_input (262144) is only the embedding size per layer.
# Temporarily override the hparams lookup order to prioritize vocab_size.
# Store original vocab_size_per_layer_input if it exists
vocab_size_per_layer_input = self.hparams.get("vocab_size_per_layer_input")
# Temporarily remove vocab_size_per_layer_input to force using vocab_size
if vocab_size_per_layer_input is not None:
del self.hparams["vocab_size_per_layer_input"]
# Call parent set_vocab which will now use vocab_size (262400)
super().set_vocab()
# Restore vocab_size_per_layer_input for later use
if vocab_size_per_layer_input is not None:
self.hparams["vocab_size_per_layer_input"] = vocab_size_per_layer_input
def set_gguf_parameters(self):
super().set_gguf_parameters()
self.gguf_writer.add_altup_active_idx(self.hparams["altup_active_idx"])
@@ -6098,8 +6287,32 @@ class Gemma3NModel(Gemma3Model):
if "language_model." not in name:
return [] # skip non-language model tensors
# Pad token embeddings for vision/audio special tokens (262144-262399)
if "embed_tokens.weight" in name or "embed_tokens_per_layer" in name:
# Move to CPU to avoid meta device issues during padding
data_torch = data_torch.to(device="cpu")
vocab_size = self.hparams.get("vocab_size", 262400)
current_size = data_torch.shape[0] # First dimension is vocab_size
if current_size < vocab_size:
# Pad with zeros for vision/audio tokens (they get embeddings from vision tower)
padding_size = vocab_size - current_size
tensor_type = "per-layer embeddings" if "per_layer" in name else "token embeddings"
logger.info(f"Padding {tensor_type} shape {list(data_torch.shape)} from {current_size} to {vocab_size} (adding {padding_size} vision/audio token slots)")
# Create padding with zeros (vision tokens won't use these embeddings)
padding = torch.zeros((padding_size, data_torch.shape[1]), dtype=data_torch.dtype, device=data_torch.device)
data_torch = torch.cat([data_torch, padding], dim=0)
# Continue with normal processing
name = name.replace("language_model.", "")
return [(self.map_tensor_name(name), data_torch)]
if "altup_unembed_projections" in name:
data_torch = data_torch.to(device="cpu")
# altup_unembed matrices are [hidden_size, hidden_size], NOT vocab-based
# They should NOT be padded
if ".0." in name:
self._altup_unembd[0] = data_torch
elif ".1." in name:
@@ -9936,7 +10149,7 @@ class LFM2Model(TextModel):
self._add_feed_forward_length()
def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iterable[tuple[str, Tensor]]:
if self._is_vision_tensor(name) or self._is_audio_tensor(name):
if self._is_vision_tensor(name) or ConformerAudioModel.is_audio_tensor(name):
# skip multimodal tensors
return []
@@ -9952,9 +10165,6 @@ class LFM2Model(TextModel):
def _is_vision_tensor(self, name: str) -> bool:
return "vision_tower" in name or "multi_modal_projector" in name
def _is_audio_tensor(self, name: str):
return any(p in name for p in ["audio", "codebook", "conformer", "depth_embedding", "depthformer", "depth_linear"])
@ModelBase.register("Lfm2Model")
class LFM2ColBertModel(LFM2Model):
@@ -10082,13 +10292,11 @@ class LFM2VLModel(MmprojModel):
@ModelBase.register("Lfm2AudioForConditionalGeneration")
class LFM2AudioModel(MmprojModel):
class LFM2AudioModel(ConformerAudioModel):
has_vision_encoder = False
has_audio_encoder = True
model_name = "Lfm2AudioEncoder"
_batch_norm_tensors: list[dict[str, Tensor]] | None = None
def get_audio_config(self) -> dict[str, Any] | None:
return self.global_config.get("encoder")
@@ -10102,12 +10310,7 @@ class LFM2AudioModel(MmprojModel):
self.gguf_writer.add_audio_num_mel_bins(self.hparams_audio["feat_in"])
self.gguf_writer.add_audio_attention_layernorm_eps(1e-5)
def tensor_force_quant(self, name, new_name, bid, n_dims):
if ".conv" in name and ".weight" in name:
return gguf.GGMLQuantizationType.F32
return super().tensor_force_quant(name, new_name, bid, n_dims)
def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iterable[tuple[str, Tensor]]:
def modify_tensors(self, data_torch, name, bid):
# skip language model tensors
if name.startswith("lfm."):
return []
@@ -10120,40 +10323,7 @@ class LFM2AudioModel(MmprojModel):
if any(p in name for p in ["codebook_offsets", "depth_embeddings", "depth_linear", "depthformer"]):
return []
# fold running_mean, running_var and eps into weight and bias for batch_norm
if "batch_norm" in name:
if self._batch_norm_tensors is None:
self._batch_norm_tensors = [{} for _ in range(self.block_count)]
assert bid is not None
self._batch_norm_tensors[bid][name] = data_torch
if len(self._batch_norm_tensors[bid]) < 5:
return []
weight = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.weight"]
bias = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.bias"]
running_mean = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.running_mean"]
running_var = self._batch_norm_tensors[bid][f"conformer.layers.{bid}.conv.batch_norm.running_var"]
eps = 1e-5 # default value
a = weight / torch.sqrt(running_var + eps)
b = bias - running_mean * a
return [
(self.map_tensor_name(f"conformer.layers.{bid}.conv.batch_norm.weight"), a),
(self.map_tensor_name(f"conformer.layers.{bid}.conv.batch_norm.bias"), b),
]
# reshape conv weights
if name.startswith("conformer.pre_encode.conv.") and name.endswith(".bias"):
data_torch = data_torch[:, None, None]
if "conv.depthwise_conv" in name and name.endswith(".weight"):
assert data_torch.shape[1] == 1
data_torch = data_torch.reshape(data_torch.shape[0], data_torch.shape[2])
if "conv.pointwise_conv" in name and name.endswith(".weight"):
assert data_torch.shape[2] == 1
data_torch = data_torch.reshape(data_torch.shape[0], data_torch.shape[1])
return [(self.map_tensor_name(name), data_torch)]
return super().modify_tensors(data_torch, name, bid)
@ModelBase.register("SmallThinkerForCausalLM")