use std::collections::HashMap;
use serde_json::{json, Value};
use crate::{
registry::{image_sizes_hw, ModelMetadata, ModelProcessorSpec, RegistryResult},
types::{ImageSize, Modality, PromptReplacement, TokenId},
vision::image_processor::PreprocessedImages,
};
pub(super) struct LlavaSpec;
impl LlavaSpec {
fn patch_size(metadata: &ModelMetadata) -> u32 {
metadata
.config_u32(&["vision_config", "patch_size"])
.unwrap_or(14)
}
fn tokens_per_image(metadata: &ModelMetadata, size: ImageSize) -> usize {
let patch = Self::patch_size(metadata);
let cols = size.width.div_ceil(patch) as usize;
let rows = size.height.div_ceil(patch) as usize;
cols * rows
}
}
impl ModelProcessorSpec for LlavaSpec {
fn name(&self) -> &'static str {
"llava"
}
fn matches(&self, metadata: &ModelMetadata) -> bool {
metadata.model_id.to_ascii_lowercase().contains("llava")
}
fn placeholder_token(&self, _metadata: &ModelMetadata) -> RegistryResult<String> {
Ok("<image>".to_string())
}
fn placeholder_token_id(&self, metadata: &ModelMetadata) -> RegistryResult<TokenId> {
if let Some(value) = metadata.config_u32(&["image_token_index"]) {
return Ok(value as TokenId);
}
metadata.token_id("<image>")
}
fn modality_limits(
&self,
_metadata: &ModelMetadata,
) -> RegistryResult<HashMap<Modality, usize>> {
Ok(HashMap::from([(Modality::Image, 4)]))
}
fn processor_kwargs(&self, _metadata: &ModelMetadata) -> RegistryResult<Value> {
Ok(json!({}))
}
fn prompt_replacements(
&self,
metadata: &ModelMetadata,
preprocessed: &PreprocessedImages,
) -> RegistryResult<Vec<PromptReplacement>> {
let token_id = self.placeholder_token_id(metadata)?;
let token = self.placeholder_token(metadata)?;
let image_sizes = image_sizes_hw(preprocessed);
Ok(image_sizes
.iter()
.map(|size| {
let count = Self::tokens_per_image(metadata, *size);
PromptReplacement::repeated(Modality::Image, &token, token_id, count)
})
.collect())
}
}
#[cfg(test)]
mod tests {
use serde_json::json;
use crate::{
registry::{test_helpers::*, ModelMetadata, ModelRegistry},
types::ImageSize,
};
#[test]
fn llava_prompt_replacement_uses_config_ids() {
let tokenizer = TestTokenizer::new(&[("<image>", 32000)]);
let config = json!({
"model_type": "llava",
"image_token_index": 32000,
"vision_config": {"patch_size": 14}
});
let metadata = ModelMetadata {
model_id: "llava-v1.5",
tokenizer: &tokenizer,
config: &config,
};
let registry = ModelRegistry::new();
let spec = registry.lookup(&metadata).expect("llava spec");
let replacements = spec
.prompt_replacements(&metadata, &test_preprocessed(&[ImageSize::new(336, 336)]))
.unwrap();
assert_eq!(replacements[0].tokens.len(), 576);
}
}