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runtime/models_v2/
florence.rs

1//! Florence Model V2 - Microsoft Vision-Language Foundation Model
2
3use crate::model_config;
4use super::traits::*;
5use anyhow::Result;
6use serde::{Serialize, Deserialize};
7
8model_config!(FlorenceConfig {
9    vocab_size: usize = 51289,
10    hidden_size: usize = 768,
11    intermediate_size: usize = 3072,
12    num_hidden_layers: usize = 12,
13    num_attention_heads: usize = 12,
14    vision_hidden_size: usize = 768,
15    vision_num_hidden_layers: usize = 12,
16    vision_num_attention_heads: usize = 12,
17    vision_patch_size: usize = 16,
18    vision_image_size: usize = 384,
19    layer_norm_eps: f32 = 1e-6,
20    pad_token_id: i64 = 1,
21    bos_token_id: i64 = 0,
22    eos_token_id: i64 = 2,
23});
24
25impl FlorenceConfig {
26    pub fn from_gguf_config(gguf: &crate::weight_loader_core::GGUFModelConfig) -> Self {
27        Self {
28            vocab_size: gguf.vocab_size,
29            hidden_size: gguf.hidden_size,
30            num_hidden_layers: gguf.num_hidden_layers,
31            num_attention_heads: gguf.num_attention_heads,
32            ..Default::default()
33        }
34    }
35}
36
37pub struct FlorenceModelV2 {
38    config: FlorenceConfig,
39    device: Device,
40    vision_tower: FlorenceVisionTower,
41    language_model: FlorenceLanguageModel,
42    projector: Tensor,
43}
44
45pub struct FlorenceVisionTower {
46    patch_embed: Tensor,
47    pos_embed: Tensor,
48    blocks: Vec<FlorenceVisionBlock>,
49    norm: Tensor,
50    hidden_size: usize,
51}
52
53pub struct FlorenceVisionBlock {
54    norm1: Tensor,
55    attn_qkv: Tensor,
56    attn_proj: Tensor,
57    norm2: Tensor,
58    mlp_fc1: Tensor,
59    mlp_fc2: Tensor,
60    num_heads: usize,
61}
62
63pub struct FlorenceLanguageModel {
64    embed_tokens: Tensor,
65    layers: Vec<FlorenceDecoderLayer>,
66    norm: Tensor,
67    lm_head: Tensor,
68}
69
70pub struct FlorenceDecoderLayer {
71    self_attn_q: Tensor,
72    self_attn_k: Tensor,
73    self_attn_v: Tensor,
74    self_attn_o: Tensor,
75    mlp_fc1: Tensor,
76    mlp_fc2: Tensor,
77    norm1: Tensor,
78    norm2: Tensor,
79    num_heads: usize,
80    head_dim: usize,
81}
82
83impl Model for FlorenceModelV2 {
84    type Config = FlorenceConfig;
85
86    fn new(config: FlorenceConfig) -> Result<Self> {
87        let device = Device::CPU;
88        let vision_tower = FlorenceVisionTower::new(&config, &device)?;
89        let language_model = FlorenceLanguageModel::new(&config, &device)?;
90        let projector = ops_fn::zeros(&[config.vision_hidden_size, config.hidden_size], DataType::Float32, &device)?;
91
92        Ok(Self { config, device, vision_tower, language_model, projector })
93    }
94
95    fn from_weights(config: FlorenceConfig, weights: ModelWeights) -> Result<Self> {
96        let mut model = Self::new(config)?;
97        model.language_model.load_weights(&weights)?;
98        Ok(model)
99    }
100
101    fn forward(&self, inputs: &ModelInputs) -> Result<ModelOutputs> {
102        match inputs {
103            ModelInputs::Text { input_ids, .. } => {
104                let hidden = ops_fn::embedding(input_ids, &self.language_model.embed_tokens)?;
105                let logits = self.language_model.forward(&hidden)?;
106                Ok(ModelOutputs::Logits { logits, hidden_states: None })
107            }
108            _ => Err(anyhow::anyhow!("Florence requires text input")),
109        }
110    }
111
112    fn generate(&self, prompt: &str, config: &GenerationConfig) -> Result<String> {
113        use crate::tokenizer::Tokenizer;
114        let tokenizer = Tokenizer::new();
115        let mut tokens: Vec<u32> = tokenizer.encode(prompt);
116
117        for _ in 0..config.max_new_tokens {
118            let input_ids = Tensor::from_i64_slice(&tokens.iter().map(|&t| t as i64).collect::<Vec<_>>(), &[1, tokens.len()], &self.device)?;
119            let outputs = self.forward(&ModelInputs::text(input_ids))?;
120            let logits = match outputs { ModelOutputs::Logits { logits, .. } => logits, _ => return Err(anyhow::anyhow!("Expected logits")) };
121
122            let logits_vec: Vec<f32> = logits.to_candle()?.flatten_all()?.to_vec1()?;
123            let start = (tokens.len() - 1) * self.config.vocab_size;
124            let next_token = logits_vec[start..start + self.config.vocab_size].iter()
125                .enumerate().max_by(|(_, a), (_, b)| a.partial_cmp(b).unwrap()).map(|(i, _)| i as u32).unwrap_or(0);
126
127            if next_token == config.eos_token_id { break; }
128            tokens.push(next_token);
129        }
130
131        Ok(tokenizer.decode(&tokens))
132    }
133
134    fn config(&self) -> &Self::Config { &self.config }
135    fn memory_requirements(&self) -> MemoryRequirements {
136        let p = (self.config.vocab_size * self.config.hidden_size) * 4;
137        MemoryRequirements { gpu_memory: p, cpu_memory: p / 4, kv_cache_memory: p / 8, peak_memory: p * 2 }
138    }
139    fn to_device(&mut self, device: &Device) -> Result<()> {
140        self.device = device.clone();
141        self.projector = self.projector.to_device(device)?;
142        Ok(())
143    }
144}
145
146impl FlorenceVisionTower {
147    fn new(config: &FlorenceConfig, device: &Device) -> Result<Self> {
148        let patch_dim = 3 * config.vision_patch_size * config.vision_patch_size;
149        let num_patches = (config.vision_image_size / config.vision_patch_size).pow(2);
150
151        let patch_embed = ops_fn::zeros(&[patch_dim, config.vision_hidden_size], DataType::Float32, device)?;
152        let pos_embed = ops_fn::zeros(&[1, num_patches + 1, config.vision_hidden_size], DataType::Float32, device)?;
153        let norm = ops_fn::zeros(&[config.vision_hidden_size], DataType::Float32, device)?;
154
155        let mut blocks = Vec::with_capacity(config.vision_num_hidden_layers);
156        for _ in 0..config.vision_num_hidden_layers {
157            blocks.push(FlorenceVisionBlock::new(config, device)?);
158        }
159
160        Ok(Self { patch_embed, pos_embed, blocks, norm, hidden_size: config.vision_hidden_size })
161    }
162}
163
164impl FlorenceVisionBlock {
165    fn new(config: &FlorenceConfig, device: &Device) -> Result<Self> {
166        Ok(Self {
167            norm1: ops_fn::zeros(&[config.vision_hidden_size], DataType::Float32, device)?,
168            attn_qkv: ops_fn::zeros(&[config.vision_hidden_size, config.vision_hidden_size * 3], DataType::Float32, device)?,
169            attn_proj: ops_fn::zeros(&[config.vision_hidden_size, config.vision_hidden_size], DataType::Float32, device)?,
170            norm2: ops_fn::zeros(&[config.vision_hidden_size], DataType::Float32, device)?,
171            mlp_fc1: ops_fn::zeros(&[config.vision_hidden_size, config.vision_hidden_size * 4], DataType::Float32, device)?,
172            mlp_fc2: ops_fn::zeros(&[config.vision_hidden_size * 4, config.vision_hidden_size], DataType::Float32, device)?,
173            num_heads: config.vision_num_attention_heads,
174        })
175    }
176}
177
178impl FlorenceLanguageModel {
179    fn new(config: &FlorenceConfig, device: &Device) -> Result<Self> {
180        let embed_tokens = ops_fn::zeros(&[config.vocab_size, config.hidden_size], DataType::Float32, device)?;
181        let norm = ops_fn::zeros(&[config.hidden_size], DataType::Float32, device)?;
182        let lm_head = ops_fn::zeros(&[config.hidden_size, config.vocab_size], DataType::Float32, device)?;
183
184        let mut layers = Vec::with_capacity(config.num_hidden_layers);
185        for _ in 0..config.num_hidden_layers {
186            layers.push(FlorenceDecoderLayer::new(config, device)?);
187        }
188
189        Ok(Self { embed_tokens, layers, norm, lm_head })
190    }
191
192    fn forward(&self, hidden_states: &Tensor) -> Result<Tensor> {
193        let mut hidden = hidden_states.clone();
194        for layer in &self.layers { hidden = layer.forward(&hidden)?; }
195        hidden = ops_fn::layer_norm(&hidden, &self.norm, None, 1e-6)?;
196        ops_fn::matmul(&hidden, &self.lm_head)
197    }
198
199    fn load_weights(&mut self, weights: &ModelWeights) -> Result<()> {
200        if let Some(w) = weights.get("model.embed_tokens.weight") { self.embed_tokens = w.clone(); }
201        if let Some(w) = weights.get("model.norm.weight") { self.norm = w.clone(); }
202        if let Some(w) = weights.get("lm_head.weight") { self.lm_head = ops_fn::transpose(w)?; }
203        Ok(())
204    }
205}
206
207impl FlorenceDecoderLayer {
208    fn new(config: &FlorenceConfig, device: &Device) -> Result<Self> {
209        let head_dim = config.hidden_size / config.num_attention_heads;
210        Ok(Self {
211            self_attn_q: ops_fn::zeros(&[config.hidden_size, config.hidden_size], DataType::Float32, device)?,
212            self_attn_k: ops_fn::zeros(&[config.hidden_size, config.hidden_size], DataType::Float32, device)?,
213            self_attn_v: ops_fn::zeros(&[config.hidden_size, config.hidden_size], DataType::Float32, device)?,
214            self_attn_o: ops_fn::zeros(&[config.hidden_size, config.hidden_size], DataType::Float32, device)?,
215            mlp_fc1: ops_fn::zeros(&[config.hidden_size, config.intermediate_size], DataType::Float32, device)?,
216            mlp_fc2: ops_fn::zeros(&[config.intermediate_size, config.hidden_size], DataType::Float32, device)?,
217            norm1: ops_fn::zeros(&[config.hidden_size], DataType::Float32, device)?,
218            norm2: ops_fn::zeros(&[config.hidden_size], DataType::Float32, device)?,
219            num_heads: config.num_attention_heads,
220            head_dim,
221        })
222    }
223
224    fn forward(&self, hidden_states: &Tensor) -> Result<Tensor> {
225        let shape = hidden_states.shape();
226        let (batch_size, seq_len, _) = (shape[0], shape[1], shape[2]);
227
228        let residual = hidden_states.clone();
229        let hidden = ops_fn::layer_norm(hidden_states, &self.norm1, None, 1e-6)?;
230
231        let q = ops_fn::matmul(&hidden, &self.self_attn_q)?.to_candle()?.reshape(&[batch_size, seq_len, self.num_heads, self.head_dim])?.transpose(1, 2)?;
232        let k = ops_fn::matmul(&hidden, &self.self_attn_k)?.to_candle()?.reshape(&[batch_size, seq_len, self.num_heads, self.head_dim])?.transpose(1, 2)?;
233        let v = ops_fn::matmul(&hidden, &self.self_attn_v)?.to_candle()?.reshape(&[batch_size, seq_len, self.num_heads, self.head_dim])?.transpose(1, 2)?;
234
235        let scale = (self.head_dim as f32).powf(-0.5);
236        let scores = (q.contiguous()?.matmul(&k.transpose(2, 3)?.contiguous()?)? * (scale as f64))?;
237        let device = scores.device();
238        let mask = { let mut m = vec![0.0f32; seq_len * seq_len]; for i in 0..seq_len { for j in (i+1)..seq_len { m[i*seq_len+j] = f32::NEG_INFINITY; } } candle_core::Tensor::from_vec(m, &[1,1,seq_len,seq_len], device)? };
239        let attn = candle_nn::ops::softmax_last_dim(&scores.broadcast_add(&mask)?)?.matmul(&v.contiguous()?)?
240            .transpose(1, 2)?.reshape(&[batch_size, seq_len, self.num_heads * self.head_dim])?;
241        let hidden = ops_fn::add(&residual, &ops_fn::matmul(&Tensor::from_candle(attn), &self.self_attn_o)?)?;
242
243        let residual = hidden.clone();
244        let hidden = ops_fn::layer_norm(&hidden, &self.norm2, None, 1e-6)?;
245        let hidden = ops_fn::gelu(&ops_fn::matmul(&hidden, &self.mlp_fc1)?)?;
246        ops_fn::add(&residual, &ops_fn::matmul(&hidden, &self.mlp_fc2)?)
247    }
248}
249
250#[cfg(test)]
251mod tests {
252    use super::*;
253
254    #[test]
255    fn test_florence_forward() {
256        let config = FlorenceConfig { vocab_size: 100, hidden_size: 32, intermediate_size: 128, num_hidden_layers: 1, num_attention_heads: 2, ..Default::default() };
257        let model = FlorenceModelV2::new(config).unwrap();
258        let outputs = model.forward(&ModelInputs::text(ops_fn::zeros(&[1, 4], DataType::Int64, &Device::CPU).unwrap())).unwrap();
259        match outputs { ModelOutputs::Logits { logits, .. } => assert_eq!(logits.shape(), &[1, 4, 100]), _ => panic!() }
260    }
261}