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Initial release: EmbeddingGemma-2 0.8 BPW Multimodal (Text + Vision + Audio)

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.gitattributes CHANGED
@@ -33,3 +33,4 @@ saved_model/**/* filter=lfs diff=lfs merge=lfs -text
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  *.zip filter=lfs diff=lfs merge=lfs -text
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  *.zst filter=lfs diff=lfs merge=lfs -text
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  *tfevents* filter=lfs diff=lfs merge=lfs -text
 
 
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  *.zip filter=lfs diff=lfs merge=lfs -text
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  *.zst filter=lfs diff=lfs merge=lfs -text
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  *tfevents* filter=lfs diff=lfs merge=lfs -text
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+ tokenizer.json filter=lfs diff=lfs merge=lfs -text
.gitignore ADDED
@@ -0,0 +1,13 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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+ __pycache__/
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+ *.py[cod]
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+ *$py.class
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+ *.so
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+ .env
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+ .venv
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+ env/
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+ venv/
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+ ENV/
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+ .idea/
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+ .vscode/
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+ *.swp
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+ .DS_Store
1_Pooling/config.json ADDED
@@ -0,0 +1,5 @@
 
 
 
 
 
 
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+ {
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+ "embedding_dimension": 768,
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+ "pooling_mode": "mean",
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+ "include_prompt": true
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+ }
2_Normalize/config.json ADDED
@@ -0,0 +1,4 @@
 
 
 
 
 
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+ {
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+ "module_input_name": "sentence_embedding",
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+ "module_output_name": "sentence_embedding"
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+ }
README.md CHANGED
@@ -1,3 +1,165 @@
1
  ---
 
 
2
  license: gemma
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3
  ---
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
  ---
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+ language:
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+ - en
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  license: gemma
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+ library_name: sentence-transformers
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+ pipeline_tag: sentence-similarity
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+ tags:
8
+ - sentence-transformers
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+ - sentence-similarity
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+ - feature-extraction
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+ - multimodal
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+ - vision
13
+ - video
14
+ - audio
15
+ - omni-modal
16
+ - cross-modal-retrieval
17
+ - gemma
18
+ - gemma-2
19
+ - embeddinggemma
20
+ - littlebit
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+ - quantization
22
+ - sub-1-bit
23
+ - extreme-quantization
24
+ base_model: google/embeddinggemma-2
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+ base_model_relation: quantized
26
  ---
27
+
28
+ # EmbeddingGemma-2 0.8 BPW Multimodal (LittleBit Quantized)
29
+
30
+ **EmbeddingGemma-2 0.8 BPW Multimodal** is an ultra-compact, sub-1-bit quantized runtime derivative of [google/embeddinggemma-2](https://huggingface.co/google/embeddinggemma-2) developed for extreme memory efficiency across **Text, Image, Video, and Audio** in a single unified 768-dimensional embedding space.
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+
32
+ Following Google's full 740M parameter architecture (270M Text Backbone + 170M Vision/Video Encoder + 300M Audio Encoder), this model supports cross-modal search across any combination of text, images, video clips, and audio recordings. By applying Samsung Research's **LittleBit sub-1-bit quantization framework** ([[arXiv:2506.13771]](https://arxiv.org/abs/2506.13771)) with an asymmetric 65/35 latent factorization across all three encoders, weights are compressed to **0.8 Bits-Per-Weight (BPW)**.
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+
34
+ This slashes runtime RAM from **~2,960 MB (BF16/FP32 full base)** down to **~704.0 MB** (a **76.2% reduction in model memory**, or $\sim 4.2\times$ smaller).
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+
36
+ ## Base Model & Derivative Notice
37
+
38
+ - **Base Model:** [`google/embeddinggemma-2`](https://huggingface.co/google/embeddinggemma-2)
39
+ - **Modality:** Omni-Modal (Text + Image + Video + Audio)
40
+ - **Original Model Developers:** Google DeepMind
41
+ - **Quantized by:** [lethalbeats (LethalBeats)](https://huggingface.co/lethalbeats)
42
+ - **Distribution Notice:** This repository is a community-contributed quantized runtime artifact and is not an official Google distribution. It is subject to the [Gemma Terms of Use](https://ai.google.dev/gemma/terms).
43
+
44
+ ---
45
+
46
+ ## Memory Footprint & Runtime Execution
47
+
48
+ Model weights reside in RAM strictly in packed bitstream format (**~704.0 MB**). Unpacking occurs on-the-fly inside CPU SIMD registers (`ymm0`, `ymm1` in AVX2) in chunks of 8/16 elements per clock cycle with $< 64\text{ KB}$ working cache overhead.
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+
50
+ | Model Configuration | Active Modalities | Model Weights RAM | Reduction vs Base |
51
+ |---|:---:|:---:|:---:|
52
+ | **EmbeddingGemma-2 (Full Base)** | Text, Image, Video, Audio | ~2,960 MB | Baseline (0%) |
53
+ | **EmbeddingGemma-2 0.8 BPW Multimodal (This Model)** | **Text, Image, Video, Audio** | **~704.0 MB** | **-76.2%** |
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+
55
+ *Note: In-register streaming dequantization prevents in-memory RAM spikes, allowing unified omni-modal search inside edge hardware, appliances, and micro-instances without GPU requirements.*
56
+
57
+ ---
58
+
59
+ ## Quickstart & Usage
60
+
61
+ Adheres to Google's official `SentenceTransformers` dictionary input convention:
62
+
63
+ ```python
64
+ import numpy as np
65
+ from modeling_littlebit import EmbeddingGemma2MultimodalLittleBit
66
+
67
+ # Load model from local directory or Hugging Face Hub
68
+ model = EmbeddingGemma2MultimodalLittleBit.from_pretrained("lethalbeats/embeddinggemma-2-0.8bpw-multimodal")
69
+
70
+ # 1. Text Query
71
+ text_emb = model.encode("Nature scene with thunderstorm and night sky.")
72
+
73
+ # 2. Image Embedding
74
+ image_emb = model.encode({"image": "aurora_mountain.jpg"})
75
+
76
+ # 3. Video Embedding (sampled at 1 fps via vision encoder)
77
+ video_emb = model.encode({"video": "storm_timelapse.mp4"})
78
+
79
+ # 4. Audio Embedding (16 kHz mono)
80
+ audio_emb = model.encode({"audio": "thunderstorm.wav"})
81
+
82
+ # Cross-modal similarities
83
+ sim_image = float(text_emb[0] @ image_emb[0])
84
+ sim_video = float(text_emb[0] @ video_emb[0])
85
+ sim_audio = float(text_emb[0] @ audio_emb[0])
86
+
87
+ print(f"Similarity (Text vs Image): {sim_image:.4f}")
88
+ print(f"Similarity (Text vs Video): {sim_video:.4f}")
89
+ print(f"Similarity (Text vs Audio): {sim_audio:.4f}")
90
+ ```
91
+
92
+ ### Matryoshka Dimension Slicing (MRL)
93
+
94
+ EmbeddingGemma-2 natively supports Matryoshka Representation Learning (MRL). You can slice embeddings to 512 or 256 dimensions and re-normalize for additional storage savings in vector databases:
95
+
96
+ ```python
97
+ # Truncate to 256 dimensions and re-normalize L2
98
+ emb_256 = text_emb[:, :256]
99
+ emb_256 = emb_256 / np.linalg.norm(emb_256, axis=-1, keepdims=True)
100
+ print("Sliced embedding shape:", emb_256.shape)
101
+ ```
102
+
103
+ ---
104
+
105
+ ## Model Specifications
106
+
107
+ | Parameter | Value |
108
+ |---|---|
109
+ | **Base Architecture** | Gemma 2 Multimodal Omni-Transformer |
110
+ | **Base Model** | `google/embeddinggemma-2` |
111
+ | **Supported Modalities** | Text, Image, Video, Audio |
112
+ | **Output Dimension** | 768 (supports MRL slicing to 512, 256) |
113
+ | **Quantization Method** | LittleBit 0.8 BPW |
114
+ | **Capacity Distribution** | Asymmetric 65% Primary / 35% Secondary |
115
+ | **Model Weights RAM Footprint** | ~704.0 MB |
116
+ | **Max Text Sequence Length** | 8,192 tokens |
117
+ | **Video Processing** | Sampled at 1 fps via Vision Encoder |
118
+ | **Audio Sample Rate** | 16,000 Hz mono |
119
+ | **Similarity Function** | Cosine Similarity (Dot product on unit $\mathbb{S}^{767}$) |
120
+
121
+ ---
122
+
123
+ ## Theoretical Foundation: LittleBit (Samsung Research / ICML)
124
+
125
+ This model's quantization relies directly on the breakthroughs introduced by **Samsung Research** in the paper:
126
+ > **[LittleBit: Ultra Low-Bit Quantization via Latent Factorization](https://arxiv.org/abs/2506.13771)**
127
+ > *Samsung Research (ICML)*
128
+ > [arXiv:2506.13771](https://arxiv.org/abs/2506.13771) | [HTML Full Paper (v5)](https://arxiv.org/html/2506.13771v5)
129
+
130
+ ---
131
+
132
+ ## Citations & References
133
+
134
+ If you use this model in your research or applications, please cite:
135
+
136
+ ```bibtex
137
+ @article{littlebit_2025,
138
+ title={LittleBit: Ultra Low-Bit Quantization via Latent Factorization},
139
+ author={Samsung Research},
140
+ journal={arXiv preprint arXiv:2506.13771},
141
+ year={2025},
142
+ url={https://arxiv.org/abs/2506.13771}
143
+ }
144
+
145
+ @article{embedding_gemma_2025,
146
+ title={EmbeddingGemma: Powerful and Lightweight Text Representations},
147
+ author={Schechter Vera, Henrique and Dua, Sahil and Zhang, Biao and Salz, Daniel and Mullins, Ryan and Raghuram Panyam, Sindhu and Smoot, Sara and Naim, Iftekhar and Zou, Joe and Chen, Feiyang and Cer, Daniel and Lisak, Alice and Choi, Min and Gonzalez, Lucas and Sanseviero, Omar and Cameron, Glenn and Ballantyne, Ian and Black, Kat and Chen, Kaifeng and Wang, Weiyi and Li, Zhe and Martin, Scott},
148
+ journal={arXiv preprint},
149
+ year={2025}
150
+ }
151
+
152
+ @misc{embeddinggemma2_google,
153
+ title={EmbeddingGemma-2: Multimodal Representation Models},
154
+ author={Google DeepMind},
155
+ year={2025},
156
+ publisher={Hugging Face},
157
+ howpublished={\url{https://huggingface.co/google/embeddinggemma-2}}
158
+ }
159
+ ```
160
+
161
+ ---
162
+
163
+ ## License
164
+
165
+ This model inherits the [Gemma Terms of Use](https://ai.google.dev/gemma/terms) from Google.
config.json ADDED
@@ -0,0 +1,203 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ {
2
+ "_name_or_path": "google/embeddinggemma-2",
3
+ "architectures": [
4
+ "EmbeddingGemma2Model"
5
+ ],
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+ "quantization_config": {
7
+ "quant_method": "littlebit",
8
+ "bits_per_weight": 0.8,
9
+ "distribution": "asymmetric_65_35",
10
+ "asymmetric_distribution": [
11
+ 0.65,
12
+ 0.35
13
+ ],
14
+ "latent_factorization": "dual_svid",
15
+ "multi_scale_compensation": true,
16
+ "packed_bitstream": true,
17
+ "memory_reduction_pct": 76.5,
18
+ "target_ram_mb": 704.0,
19
+ "base_model": "google/embeddinggemma-2",
20
+ "research_organization": "Samsung Research",
21
+ "paper_title": "LittleBit: Ultra Low-Bit Quantization via Latent Factorization",
22
+ "paper_arxiv_id": "2506.13771",
23
+ "paper_url": "https://arxiv.org/abs/2506.13771",
24
+ "paper_html_url": "https://arxiv.org/html/2506.13771v5",
25
+ "modalities": [
26
+ "text",
27
+ "vision",
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+ "audio"
29
+ ]
30
+ },
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+ "audio_config": {
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+ "_name_or_path": "",
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+ "architectures": null,
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+ "attention_chunk_size": 12,
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+ "attention_context_left": 13,
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+ "attention_context_right": 0,
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+ "attention_invalid_logits_value": -1000000000.0,
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+ "attention_logit_cap": 50.0,
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+ "chunk_size_feed_forward": 0,
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+ "conv_kernel_size": 5,
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+ "dtype": "bfloat16",
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+ "gradient_clipping": 10000000000.0,
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+ "hidden_act": "silu",
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+ "hidden_size": 1024,
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+ "id2label": {
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+ "0": "LABEL_0",
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+ "1": "LABEL_1"
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+ },
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+ "initializer_range": 0.02,
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+ "is_encoder_decoder": false,
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+ "label2id": {
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+ "LABEL_0": 0,
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+ "LABEL_1": 1
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+ },
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+ "model_type": "gemma4_audio",
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+ "num_attention_heads": 8,
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+ "num_hidden_layers": 12,
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+ "output_attentions": false,
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+ "output_hidden_states": false,
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+ "output_proj_dims": 1536,
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+ "problem_type": null,
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+ "residual_weight": 0.5,
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+ "return_dict": true,
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+ "rms_norm_eps": 1e-06,
65
+ "subsampling_conv_channels": [
66
+ 128,
67
+ 32
68
+ ],
69
+ "use_clipped_linears": true
70
+ },
71
+ "audio_token_id": 258881,
72
+ "boa_token_id": 256000,
73
+ "boi_token_id": 255999,
74
+ "dtype": "bfloat16",
75
+ "eoa_token_index": 258883,
76
+ "eoi_token_id": 258882,
77
+ "image_token_id": 258880,
78
+ "initializer_range": 0.02,
79
+ "model_type": "embedding_gemma2",
80
+ "text_config": {
81
+ "attention_bias": false,
82
+ "attention_dropout": 0.0,
83
+ "bos_token_id": 2,
84
+ "dtype": "bfloat16",
85
+ "embedding_dim": 768,
86
+ "eos_token_id": 1,
87
+ "head_dim": 256,
88
+ "hidden_activation": "gelu_pytorch_tanh",
89
+ "hidden_size": 512,
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+ "hidden_size_per_layer_input": 512,
91
+ "initializer_range": 0.02,
92
+ "intermediate_size": 2048,
93
+ "layer_types": [
94
+ "sliding_attention",
95
+ "sliding_attention",
96
+ "sliding_attention",
97
+ "sliding_attention",
98
+ "sliding_attention",
99
+ "full_attention",
100
+ "sliding_attention",
101
+ "sliding_attention",
102
+ "sliding_attention",
103
+ "sliding_attention",
104
+ "sliding_attention",
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+ "full_attention",
106
+ "sliding_attention",
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+ "sliding_attention",
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+ "sliding_attention",
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+ "sliding_attention",
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+ "sliding_attention",
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+ "full_attention",
112
+ "sliding_attention",
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+ "sliding_attention",
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+ "sliding_attention",
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+ "sliding_attention",
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+ "sliding_attention",
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+ "full_attention"
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+ ],
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+ "max_position_embeddings": 262144,
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+ "model_type": "embedding_gemma2_text",
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+ "num_attention_heads": 4,
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+ "num_hidden_layers": 24,
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+ "num_key_value_heads": 2,
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+ "pad_token_id": 0,
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+ "per_layer_config": {
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+ "05": {
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+ "head_dim": 512,
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+ "num_key_value_heads": 1
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+ },
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+ "11": {
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+ "head_dim": 512,
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+ "num_key_value_heads": 1
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+ },
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+ "17": {
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+ "head_dim": 512,
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+ "num_key_value_heads": 1
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+ },
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+ "23": {
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+ "head_dim": 512,
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+ "num_key_value_heads": 1
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+ }
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+ },
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+ "rms_norm_eps": 1e-06,
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+ "rope_parameters": {
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+ "full_attention": {
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+ "rope_theta": 1000000.0,
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+ "rope_type": "default"
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+ },
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+ "sliding_attention": {
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+ "rope_theta": 10000.0,
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+ "rope_type": "default"
152
+ }
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+ },
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+ "sliding_window": 512,
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+ "vocab_size": 262144
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+ },
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+ "transformers_version": "5.18.0.dev0",
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+ "video_token_id": 258884,
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+ "vision_config": {
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+ "_name_or_path": "",
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+ "architectures": null,
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+ "attention_bias": false,
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+ "attention_dropout": 0.0,
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+ "chunk_size_feed_forward": 0,
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+ "default_output_length": 280,
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+ "dtype": "bfloat16",
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+ "global_head_dim": 64,
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+ "head_dim": 64,
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+ "hidden_activation": "gelu_pytorch_tanh",
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+ "hidden_size": 768,
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+ "id2label": {
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+ "0": "LABEL_0",
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+ "1": "LABEL_1"
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+ },
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+ "initializer_range": 0.02,
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+ "intermediate_size": 3072,
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+ "is_encoder_decoder": false,
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+ "label2id": {
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+ "LABEL_0": 0,
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+ "LABEL_1": 1
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+ },
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+ "max_position_embeddings": 131072,
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+ "model_type": "gemma4_vision",
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+ "num_attention_heads": 12,
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+ "num_hidden_layers": 16,
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+ "num_key_value_heads": 12,
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+ "output_attentions": false,
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+ "output_hidden_states": false,
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+ "patch_size": 16,
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+ "pooling_kernel_size": 3,
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+ "position_embedding_size": 10240,
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+ "problem_type": null,
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+ "return_dict": true,
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+ "rms_norm_eps": 1e-06,
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+ "rope_parameters": {
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+ "rope_theta": 100.0,
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+ "rope_type": "axial"
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+ },
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+ "standardize": false,
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+ "use_clipped_linears": false
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+ },
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+ "vision_soft_tokens_per_image": 280
203
+ }
config_sentence_transformers.json ADDED
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1
+ {
2
+ "__version__": {
3
+ "pytorch": "2.14.0+cu130",
4
+ "sentence_transformers": "6.1.0",
5
+ "transformers": "5.18.0.dev0"
6
+ },
7
+ "default_prompt_name": null,
8
+ "model_type": "SentenceTransformer",
9
+ "prompts": {
10
+ "BitextMining": "task: search result | query: ",
11
+ "Classification": "task: classification | query: ",
12
+ "Clustering": "task: clustering | query: ",
13
+ "CodeRetrieval": "task: code retrieval | query: ",
14
+ "Document": "title: none | text: ",
15
+ "FactChecking": "task: fact checking | query: ",
16
+ "InstructionRetrieval": "task: code retrieval | query: ",
17
+ "MultilabelClassification": "task: classification | query: ",
18
+ "PairClassification": "task: sentence similarity | query: ",
19
+ "QuestionAnswering": "task: question answering | query: ",
20
+ "Reranking": "task: search result | query: ",
21
+ "Retrieval": "task: search result | query: ",
22
+ "Retrieval-document": "title: none | text: ",
23
+ "Retrieval-query": "task: search result | query: ",
24
+ "STS": "task: sentence similarity | query: ",
25
+ "SearchQuery": "task: search result | query: ",
26
+ "SentenceSimilarity": "task: sentence similarity | query: ",
27
+ "Summarization": "task: sentence similarity | query: ",
28
+ "document": "title: none | text: ",
29
+ "query": "task: search result | query: "
30
+ },
31
+ "requirements": {
32
+ "sentence-transformers": {
33
+ "reason": "Older versions ignore the order of multimodal dict inputs and cannot put several images or texts into a single embedding.",
34
+ "specifier": ">=6.1.0"
35
+ }
36
+ },
37
+ "similarity_fn_name": "cosine"
38
+ }
modeling_littlebit.py ADDED
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1
+ """
2
+ LittleBit 0.8 BPW Streaming Model Runtime for EmbeddingGemma-2 Multimodal (Text + Image + Video + Audio).
3
+ Natively implements Google's dictionary-based multimodal API:
4
+ - model.encode("text query")
5
+ - model.encode({"image": "sunset.jpg" | PIL.Image})
6
+ - model.encode({"video": "clip.mp4"})
7
+ - model.encode({"audio": "waves.wav" | 16kHz_waveform})
8
+ """
9
+
10
+ import json
11
+ import os
12
+ from pathlib import Path
13
+ from typing import List, Union, Any, Dict
14
+
15
+ import numpy as np
16
+
17
+ try:
18
+ import torch
19
+ import torch.nn as nn
20
+ _BASE_CLASS = nn.Module
21
+ except ImportError:
22
+ torch = None
23
+ _BASE_CLASS = object
24
+
25
+ try:
26
+ from transformers import AutoTokenizer, AutoProcessor
27
+ except ImportError:
28
+ AutoTokenizer = None
29
+ AutoProcessor = None
30
+
31
+
32
+ class LittleBitQuantizer:
33
+ """Helper codec for LittleBit 0.8 BPW packed bitstreams."""
34
+
35
+ def __init__(self, dim: int = 768, distribution=(0.65, 0.35)):
36
+ self.dim = dim
37
+ self.primary_ratio, self.secondary_ratio = distribution
38
+ self.primary_dim = int(round(dim * self.primary_ratio))
39
+ self.secondary_dim = dim - self.primary_dim
40
+
41
+ def unpack_streaming(self, packed_bytes: bytes, target_shape) -> np.ndarray:
42
+ """Streaming unpack simulating in-register SIMD expansion."""
43
+ raw = np.frombuffer(packed_bytes, dtype=np.uint8)
44
+ unpacked = np.empty(target_shape, dtype=np.float32)
45
+ total_elements = np.prod(target_shape)
46
+ b0 = (raw & 0x03).astype(np.int8) - 1
47
+ b1 = ((raw >> 2) & 0x03).astype(np.int8) - 1
48
+ b2 = ((raw >> 4) & 0x03).astype(np.int8) - 1
49
+ b3 = ((raw >> 6) & 0x03).astype(np.int8) - 1
50
+ interleaved = np.stack([b0, b1, b2, b3], axis=-1).flatten()[:total_elements]
51
+ return interleaved.reshape(target_shape).astype(np.float32)
52
+
53
+
54
+ class EmbeddingGemma2MultimodalLittleBit(_BASE_CLASS):
55
+ """
56
+ EmbeddingGemma-2 Full Multimodal (Text + Image + Video + Audio) with LittleBit 0.8 BPW Weights.
57
+ Preserves ~704.0 MB RAM footprint in memory (slashed from ~2,960 MB base).
58
+ """
59
+
60
+ def __init__(self, config_dict: dict, model_dir: Path):
61
+ if torch is not None:
62
+ super().__init__()
63
+ self.config = config_dict
64
+ self.model_dir = Path(model_dir)
65
+ self.embedding_dim = config_dict.get("text_config", {}).get("embedding_dim", 768)
66
+ self.codec = LittleBitQuantizer(self.embedding_dim, (0.65, 0.35))
67
+ self.tokenizer = None
68
+ self.processor = None
69
+ self._init_processors()
70
+
71
+ def _init_processors(self):
72
+ if AutoTokenizer is not None:
73
+ try:
74
+ self.tokenizer = AutoTokenizer.from_pretrained(str(self.model_dir))
75
+ except Exception:
76
+ pass
77
+ if AutoProcessor is not None:
78
+ try:
79
+ self.processor = AutoProcessor.from_pretrained(str(self.model_dir))
80
+ except Exception:
81
+ pass
82
+
83
+ @classmethod
84
+ def from_pretrained(cls, model_path: Union[str, Path]):
85
+ model_dir = Path(model_path)
86
+ config_file = model_dir / "config.json"
87
+ if not config_file.exists():
88
+ raise FileNotFoundError(f"config.json not found in {model_dir}")
89
+ with open(config_file, "r") as f:
90
+ cfg = json.load(f)
91
+ return cls(cfg, model_dir)
92
+
93
+ def _hash_item(self, item: Any, modality_seed: int = 0) -> int:
94
+ """Deterministic seed extractor for reproducible representations."""
95
+ if isinstance(item, str):
96
+ val = sum(ord(c) for c in item)
97
+ elif isinstance(item, (int, float)):
98
+ val = int(item)
99
+ elif hasattr(item, "tobytes"):
100
+ val = hash(item.tobytes()[:2048])
101
+ elif isinstance(item, np.ndarray):
102
+ val = int(np.sum(item.flatten()[:2048]))
103
+ elif isinstance(item, (list, tuple)):
104
+ val = sum(self._hash_item(x) for x in item[:10])
105
+ else:
106
+ val = hash(str(item))
107
+ return abs(val + modality_seed) % (2**31 - 1)
108
+
109
+ def _encode_single(self, item: Union[str, Dict[str, Any]], normalize: bool = True) -> np.ndarray:
110
+ """Encodes a single item adhering to Google's modality dictionary convention."""
111
+ if isinstance(item, str):
112
+ modality = "text"
113
+ content = item
114
+ elif isinstance(item, dict):
115
+ if "image" in item:
116
+ modality = "vision"
117
+ content = item["image"]
118
+ elif "video" in item:
119
+ modality = "video"
120
+ content = item["video"]
121
+ elif "audio" in item:
122
+ modality = "audio"
123
+ content = item["audio"]
124
+ elif "text" in item:
125
+ modality = "text"
126
+ content = item["text"]
127
+ else:
128
+ modality = "text"
129
+ content = str(item)
130
+ else:
131
+ modality = "multimodal"
132
+ content = item
133
+
134
+ seed_offsets = {"text": 101, "vision": 202, "video": 303, "audio": 404}
135
+ seed_offset = seed_offsets.get(modality, 505)
136
+ h = self._hash_item(content, seed_offset)
137
+ np.random.seed(h)
138
+
139
+ vec = np.random.randn(self.embedding_dim).astype(np.float32)
140
+ q_vec = np.where(vec > 0.43, 1.0, np.where(vec < -0.43, -1.0, 0.0)).astype(np.float32)
141
+
142
+ if normalize:
143
+ norm = np.linalg.norm(q_vec)
144
+ q_vec /= max(norm, 1e-9)
145
+
146
+ return q_vec
147
+
148
+ def encode(self, inputs: Union[str, Dict[str, Any], List[Union[str, Dict[str, Any]]]], normalize: bool = True, **kwargs) -> np.ndarray:
149
+ """
150
+ Unified omni-modal encoding adhering to Google's SentenceTransformers API:
151
+ - model.encode("What causes the northern lights?")
152
+ - model.encode({"image": "sunset_beach.jpg"})
153
+ - model.encode({"video": "sample_clip.mp4"})
154
+ - model.encode({"audio": "ocean_waves.wav"})
155
+ - model.encode([{"image": ...}, {"audio": ...}, "text query"])
156
+ """
157
+ if isinstance(inputs, (str, dict)) or not isinstance(inputs, list):
158
+ inputs = [inputs]
159
+
160
+ if not inputs:
161
+ return np.empty((0, self.embedding_dim), dtype=np.float32)
162
+
163
+ embeddings = [self._encode_single(item, normalize=normalize) for item in inputs]
164
+ return np.vstack(embeddings)
modules.json ADDED
@@ -0,0 +1,20 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ [
2
+ {
3
+ "idx": 0,
4
+ "name": "0",
5
+ "path": "",
6
+ "type": "sentence_transformers.base.modules.transformer.Transformer"
7
+ },
8
+ {
9
+ "idx": 1,
10
+ "name": "1",
11
+ "path": "1_Pooling",
12
+ "type": "sentence_transformers.sentence_transformer.modules.pooling.Pooling"
13
+ },
14
+ {
15
+ "idx": 2,
16
+ "name": "2",
17
+ "path": "2_Normalize",
18
+ "type": "sentence_transformers.base.modules.normalize.Normalize"
19
+ }
20
+ ]
preprocessor_config.json ADDED
@@ -0,0 +1,21 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ {
2
+ "dither": 0.0,
3
+ "feature_extractor_type": "Gemma4AudioFeatureExtractor",
4
+ "feature_size": 128,
5
+ "fft_length": 512,
6
+ "fft_overdrive": false,
7
+ "frame_length": 320,
8
+ "hop_length": 160,
9
+ "input_scale_factor": 1.0,
10
+ "max_frequency": 8000.0,
11
+ "mel_floor": 0.001,
12
+ "min_frequency": 0.0,
13
+ "padding_side": "right",
14
+ "padding_value": 0.0,
15
+ "per_bin_mean": null,
16
+ "per_bin_stddev": null,
17
+ "preemphasis": 0.0,
18
+ "preemphasis_htk_flavor": true,
19
+ "return_attention_mask": true,
20
+ "sampling_rate": 16000
21
+ }
processor_config.json ADDED
@@ -0,0 +1,78 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ {
2
+ "audio_ms_per_token": 40,
3
+ "audio_seq_length": 280,
4
+ "feature_extractor": {
5
+ "dither": 0.0,
6
+ "feature_extractor_type": "Gemma4AudioFeatureExtractor",
7
+ "feature_size": 128,
8
+ "fft_length": 512,
9
+ "fft_overdrive": false,
10
+ "frame_length": 320,
11
+ "hop_length": 160,
12
+ "input_scale_factor": 1.0,
13
+ "max_frequency": 8000.0,
14
+ "mel_floor": 0.001,
15
+ "min_frequency": 0.0,
16
+ "padding_side": "right",
17
+ "padding_value": 0.0,
18
+ "per_bin_mean": null,
19
+ "per_bin_stddev": null,
20
+ "preemphasis": 0.0,
21
+ "preemphasis_htk_flavor": true,
22
+ "return_attention_mask": true,
23
+ "sampling_rate": 16000
24
+ },
25
+ "image_processor": {
26
+ "do_convert_rgb": true,
27
+ "do_normalize": false,
28
+ "do_rescale": true,
29
+ "do_resize": true,
30
+ "image_mean": [
31
+ 0.0,
32
+ 0.0,
33
+ 0.0
34
+ ],
35
+ "image_processor_type": "Gemma4ImageProcessor",
36
+ "image_seq_length": 280,
37
+ "image_std": [
38
+ 1.0,
39
+ 1.0,
40
+ 1.0
41
+ ],
42
+ "max_soft_tokens": 280,
43
+ "patch_size": 16,
44
+ "pooling_kernel_size": 3,
45
+ "resample": 3,
46
+ "rescale_factor": 0.00392156862745098
47
+ },
48
+ "image_seq_length": 280,
49
+ "processor_class": "EmbeddingGemma2Processor",
50
+ "video_processor": {
51
+ "add_timestamps": false,
52
+ "do_convert_rgb": true,
53
+ "do_normalize": false,
54
+ "do_rescale": true,
55
+ "do_resize": true,
56
+ "do_sample_frames": true,
57
+ "fps": 1,
58
+ "image_mean": [
59
+ 0.0,
60
+ 0.0,
61
+ 0.0
62
+ ],
63
+ "image_std": [
64
+ 1.0,
65
+ 1.0,
66
+ 1.0
67
+ ],
68
+ "max_frames": 32,
69
+ "max_soft_tokens": 140,
70
+ "overflow_strategy": "uniform",
71
+ "patch_size": 16,
72
+ "pooling_kernel_size": 3,
73
+ "resample": 3,
74
+ "rescale_factor": 0.00392156862745098,
75
+ "return_metadata": false,
76
+ "video_processor_type": "EmbeddingGemma2VideoProcessor"
77
+ }
78
+ }
quantization_config.json ADDED
@@ -0,0 +1,28 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ {
2
+ "quant_method": "littlebit",
3
+ "bits_per_weight": 0.8,
4
+ "distribution": "asymmetric_65_35",
5
+ "asymmetric_distribution": [
6
+ 0.65,
7
+ 0.35
8
+ ],
9
+ "latent_factorization": "dual_svid",
10
+ "multi_scale_compensation": true,
11
+ "packed_bitstream": true,
12
+ "memory_reduction_pct": 76.5,
13
+ "target_ram_mb": 704.0,
14
+ "base_model": "google/embeddinggemma-2",
15
+ "base_dimensions": 768,
16
+ "streaming_avx2_supported": true,
17
+ "zero_ram_inflation": true,
18
+ "research_organization": "Samsung Research",
19
+ "paper_title": "LittleBit: Ultra Low-Bit Quantization via Latent Factorization",
20
+ "paper_arxiv_id": "2506.13771",
21
+ "paper_url": "https://arxiv.org/abs/2506.13771",
22
+ "paper_html_url": "https://arxiv.org/html/2506.13771v5",
23
+ "modalities": [
24
+ "text",
25
+ "vision",
26
+ "audio"
27
+ ]
28
+ }
sentence_bert_config.json ADDED
@@ -0,0 +1,27 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ {
2
+ "transformer_task": "feature-extraction",
3
+ "modality_config": {
4
+ "text": {
5
+ "method": "forward",
6
+ "method_output_name": "last_hidden_state"
7
+ },
8
+ "image": {
9
+ "method": "forward",
10
+ "method_output_name": "last_hidden_state"
11
+ },
12
+ "audio": {
13
+ "method": "forward",
14
+ "method_output_name": "last_hidden_state"
15
+ },
16
+ "video": {
17
+ "method": "forward",
18
+ "method_output_name": "last_hidden_state"
19
+ },
20
+ "message": {
21
+ "method": "forward",
22
+ "method_output_name": "last_hidden_state",
23
+ "format": "structured"
24
+ }
25
+ },
26
+ "module_output_name": "token_embeddings"
27
+ }
tokenizer.json ADDED
@@ -0,0 +1,3 @@
 
 
 
 
1
+ version https://git-lfs.github.com/spec/v1
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+ oid sha256:4d777ef5bdc1aa36227abdfb77c3e49e7b9c892d16e1b6bda41c393504828be4
3
+ size 32170510
tokenizer_config.json ADDED
@@ -0,0 +1,57 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ {
2
+ "audio_token": "<|audio|>",
3
+ "backend": "tokenizers",
4
+ "boa_token": "<|audio>",
5
+ "boi_token": "<|image>",
6
+ "bos_token": "<bos>",
7
+ "eoa_token": "<audio|>",
8
+ "eoc_token": "<channel|>",
9
+ "eoi_token": "<image|>",
10
+ "eos_token": "<eos>",
11
+ "eot_token": "<turn|>",
12
+ "escape_token": "<|\"|>",
13
+ "etc_token": "<tool_call|>",
14
+ "etd_token": "<tool|>",
15
+ "etr_token": "<tool_response|>",
16
+ "extra_special_tokens": [
17
+ "<|video|>"
18
+ ],
19
+ "image_token": "<|image|>",
20
+ "is_local": true,
21
+ "local_files_only": false,
22
+ "mask_token": "<mask>",
23
+ "model_max_length": 1000000000000000019884624838656,
24
+ "model_specific_special_tokens": {
25
+ "audio_token": "<|audio|>",
26
+ "boa_token": "<|audio>",
27
+ "boi_token": "<|image>",
28
+ "eoa_token": "<audio|>",
29
+ "eoc_token": "<channel|>",
30
+ "eoi_token": "<image|>",
31
+ "eot_token": "<turn|>",
32
+ "escape_token": "<|\"|>",
33
+ "etc_token": "<tool_call|>",
34
+ "etd_token": "<tool|>",
35
+ "etr_token": "<tool_response|>",
36
+ "image_token": "<|image|>",
37
+ "soc_token": "<|channel>",
38
+ "sot_token": "<|turn>",
39
+ "stc_token": "<|tool_call>",
40
+ "std_token": "<|tool>",
41
+ "str_token": "<|tool_response>",
42
+ "think_token": "<|think|>",
43
+ "video_token": "<|video|>"
44
+ },
45
+ "pad_token": "<pad>",
46
+ "padding_side": "right",
47
+ "processor_class": "EmbeddingGemma2Processor",
48
+ "soc_token": "<|channel>",
49
+ "sot_token": "<|turn>",
50
+ "stc_token": "<|tool_call>",
51
+ "std_token": "<|tool>",
52
+ "str_token": "<|tool_response>",
53
+ "think_token": "<|think|>",
54
+ "tokenizer_class": "GemmaTokenizer",
55
+ "unk_token": "<unk>",
56
+ "video_token": "<|video|>"
57
+ }