bridge.models.gemma_vl.gemma4_vl_bridge#

Megatron Bridge for Gemma 4 Vision-Language (ConditionalGeneration).

Text conversion logic is inherited from

class:

~megatron.bridge.models.gemma.gemma4_bridge.Gemma4Bridge.

Usage::

AutoBridge.from_hf_pretrained(“google/gemma-4-E4B-it”) └─ Gemma4VLBridge (registered for Gemma4ForConditionalGeneration) ├─ provider_bridge() text mode → Gemma4DenseProvider (pretraining) │ auto/vl → Gemma4DenseVLProvider (full VL) └─ mapping_registry() Dense → _dense_vl_mapping_registry() MoE → _moe_vl_mapping_registry()

Module Contents#

Classes#

Gemma4VLBridge

Megatron Bridge for Gemma 4 Vision-Language models.

API#

class bridge.models.gemma_vl.gemma4_vl_bridge.Gemma4VLBridge#

Bases: megatron.bridge.models.gemma.gemma4_bridge.Gemma4Bridge

Megatron Bridge for Gemma 4 Vision-Language models.

Inherits all Dense/MoE logic from Gemma4Bridge and adds VL-specific:

  • vision_tower and embed_vision weight mappings

  • Dense E4B VL provider construction

  • GEMMA4_CONVERSION_MODE dispatch (text / auto / vl)

provider_bridge(
hf_pretrained: megatron.bridge.models.hf_pretrained.causal_lm.PreTrainedCausalLM,
) → Gemma4VLModelProvider | Gemma4DenseVLProvider | Gemma4DenseProvider#
classmethod megatron_to_hf_config(
provider: megatron.bridge.models.gemma_vl.gemma4_vl_provider.Gemma4VLModelProvider | megatron.bridge.models.gemma_vl.gemma4_vl_provider.Gemma4DenseVLProvider | megatron.bridge.models.gemma.gemma4_provider.Gemma4DenseProvider,
) → dict#

Convert a Gemma 4 VL provider config back to Hugging Face config.

_conversion_mode() → str#
_build_dense_vl_provider(
hf_config,
text_config,
vision_config,
) → megatron.bridge.models.gemma_vl.gemma4_vl_provider.Gemma4DenseVLProvider#

Build a Dense VL provider by copying all Dense provider fields.

_text_config()#
_hf_layer_prefix() → str#

VLM text weights live under model.language_model.*.

mapping_registry() → megatron.bridge.models.conversion.mapping_registry.MegatronMappingRegistry#

Dispatch to Dense or MoE VLM mappings.

_dense_vl_mapping_registry() → megatron.bridge.models.conversion.mapping_registry.MegatronMappingRegistry#

Dense E4B VL: language mappings + vision tower + audio tower.

_moe_vl_mapping_registry() → megatron.bridge.models.conversion.mapping_registry.MegatronMappingRegistry#

MoE VL parameter mappings.