Add Stable Diffusion 3 Example (#2558)

* Add stable diffusion 3 example

Add get_qkv_linear to handle different dimensionality in linears

Add stable diffusion 3 example

Add use_quant_conv and use_post_quant_conv for vae in stable diffusion

adapt existing AutoEncoderKLConfig to the change

add forward_until_encoder_layer to ClipTextTransformer

rename sd3 config to sd3_medium in mmdit; minor clean-up

Enable flash-attn for mmdit impl when the feature is enabled.

Add sd3 example codebase

add document

crediting references

pass the cargo fmt test

pass the clippy test

* fix typos

* expose cfg_scale and time_shift as options

* Replace the sample image with JPG version. Change image output format accordingly.

* make meaningful error messages

* remove the tail-end assignment in sd3_vae_vb_rename

* remove the CUDA requirement

* use default_value in clap args

* add use_flash_attn to turn on/off flash-attn for MMDiT at runtime

* resolve clippy errors and warnings

* use default_value_t

* Pin the web-sys dependency.

* Clippy fix.

---------

Co-authored-by: Laurent <[email protected]>

candle-examples/Cargo.toml

@@ -122,3 +122,6 @@ required-features = ["onnx"]
 [[example]]
 name = "colpali"
 required-features = ["pdf2image"]
+
+[[example]]
+name = "stable-diffusion-3"

candle-examples/examples/stable-diffusion-3/README.md

@@ -0,0 +1,54 @@
+# candle-stable-diffusion-3: Candle Implementation of Stable Diffusion 3 Medium
+
+![](assets/stable-diffusion-3.jpg)
+
+*A cute rusty robot holding a candle torch in its hand, with glowing neon text \"LETS GO RUSTY\" displayed on its chest, bright background, high quality, 4k*
+
+Stable Diffusion 3 Medium is a text-to-image model based on Multimodal Diffusion Transformer (MMDiT) architecture.
+
+- [huggingface repo](https://huggingface.co/stabilityai/stable-diffusion-3-medium)
+- [research paper](https://arxiv.org/pdf/2403.03206)
+- [announcement blog post](https://stability.ai/news/stable-diffusion-3-medium)
+
+## Getting access to the weights
+
+The weights of Stable Diffusion 3 Medium is released by Stability AI under the Stability Community License. You will need to accept the conditions and acquire a license by visiting the [repo on HuggingFace Hub](https://huggingface.co/stabilityai/stable-diffusion-3-medium) to gain access to the weights for your HuggingFace account.
+
+On the first run, the weights will be automatically downloaded from the Huggingface Hub. You might be prompted to configure a [Huggingface User Access Tokens](https://huggingface.co/docs/hub/en/security-tokens) (recommended) on your computer if you haven't done that before. After the download, the weights will be [cached](https://huggingface.co/docs/datasets/en/cache) and remain accessible locally.
+
+## Running the model
+
+```shell
+cargo run --example stable-diffusion-3 --release --features=cuda -- \
+  --height 1024 --width 1024 \
+  --prompt 'A cute rusty robot holding a candle torch in its hand, with glowing neon text \"LETS GO RUSTY\" displayed on its chest, bright background, high quality, 4k'
+```
+
+To display other options available,
+
+```shell
+cargo run --example stable-diffusion-3 --release --features=cuda -- --help
+```
+
+If GPU supports, Flash-Attention is a strongly recommended feature as it can greatly improve the speed of inference, as MMDiT is a transformer model heavily depends on attentions. To utilize [candle-flash-attn](https://github.com/huggingface/candle/tree/main/candle-flash-attn) in the demo, you will need both `--features flash-attn` and `--use-flash-attn`.
+
+```shell
+cargo run --example stable-diffusion-3 --release --features=cuda,flash-attn -- --use-flash-attn ...
+```
+
+## Performance Benchmark
+
+Below benchmark is done by generating 1024-by-1024 image from 28 steps of Euler sampling and measure the average speed (iteration per seconds).
+
+[candle](https://github.com/huggingface/candle) and [candle-flash-attn](https://github.com/huggingface/candle/tree/main/candle-flash-attn) is based on the commit of [0d96ec3](https://github.com/huggingface/candle/commit/0d96ec31e8be03f844ed0aed636d6217dee9c7bc).
+
+System specs (Desktop PCIE 5 x8/x8 dual-GPU setup):
+
+- Operating System: Ubuntu 23.10
+- CPU: i9 12900K w/o overclocking.
+- RAM: 64G dual-channel DDR5 @ 4800 MT/s
+
+| Speed (iter/s) | w/o flash-attn | w/ flash-attn |
+| -------------- | -------------- | ------------- |
+| RTX 3090 Ti    | 0.83           | 2.15          |
+| RTX 4090       | 1.72           | 4.06          |

candle-examples/examples/stable-diffusion-3/clip.rs

@@ -0,0 +1,201 @@
+use anyhow::{Error as E, Ok, Result};
+use candle::{DType, IndexOp, Module, Tensor, D};
+use candle_transformers::models::{stable_diffusion, t5};
+use tokenizers::tokenizer::Tokenizer;
+
+struct ClipWithTokenizer {
+    clip: stable_diffusion::clip::ClipTextTransformer,
+    config: stable_diffusion::clip::Config,
+    tokenizer: Tokenizer,
+    max_position_embeddings: usize,
+}
+
+impl ClipWithTokenizer {
+    fn new(
+        vb: candle_nn::VarBuilder,
+        config: stable_diffusion::clip::Config,
+        tokenizer_path: &str,
+        max_position_embeddings: usize,
+    ) -> Result<Self> {
+        let clip = stable_diffusion::clip::ClipTextTransformer::new(vb, &config)?;
+        let path_buf = hf_hub::api::sync::Api::new()?
+            .model(tokenizer_path.to_string())
+            .get("tokenizer.json")?;
+        let tokenizer = Tokenizer::from_file(path_buf.to_str().ok_or(E::msg(
+            "Failed to serialize huggingface PathBuf of CLIP tokenizer",
+        ))?)
+        .map_err(E::msg)?;
+        Ok(Self {
+            clip,
+            config,
+            tokenizer,
+            max_position_embeddings,
+        })
+    }
+
+    fn encode_text_to_embedding(
+        &self,
+        prompt: &str,
+        device: &candle::Device,
+    ) -> Result<(Tensor, Tensor)> {
+        let pad_id = match &self.config.pad_with {
+            Some(padding) => *self
+                .tokenizer
+                .get_vocab(true)
+                .get(padding.as_str())
+                .ok_or(E::msg("Failed to tokenize CLIP padding."))?,
+            None => *self
+                .tokenizer
+                .get_vocab(true)
+                .get("<|endoftext|>")
+                .ok_or(E::msg("Failed to tokenize CLIP end-of-text."))?,
+        };
+
+        let mut tokens = self
+            .tokenizer
+            .encode(prompt, true)
+            .map_err(E::msg)?
+            .get_ids()
+            .to_vec();
+
+        let eos_position = tokens.len() - 1;
+
+        while tokens.len() < self.max_position_embeddings {
+            tokens.push(pad_id)
+        }
+        let tokens = Tensor::new(tokens.as_slice(), device)?.unsqueeze(0)?;
+        let (text_embeddings, text_embeddings_penultimate) = self
+            .clip
+            .forward_until_encoder_layer(&tokens, usize::MAX, -2)?;
+        let text_embeddings_pooled = text_embeddings.i((0, eos_position, ..))?;
+
+        Ok((text_embeddings_penultimate, text_embeddings_pooled))
+    }
+}
+
+struct T5WithTokenizer {
+    t5: t5::T5EncoderModel,
+    tokenizer: Tokenizer,
+    max_position_embeddings: usize,
+}
+
+impl T5WithTokenizer {
+    fn new(vb: candle_nn::VarBuilder, max_position_embeddings: usize) -> Result<Self> {
+        let api = hf_hub::api::sync::Api::new()?;
+        let repo = api.repo(hf_hub::Repo::with_revision(
+            "google/t5-v1_1-xxl".to_string(),
+            hf_hub::RepoType::Model,
+            "refs/pr/2".to_string(),
+        ));
+        let config_filename = repo.get("config.json")?;
+        let config = std::fs::read_to_string(config_filename)?;
+        let config: t5::Config = serde_json::from_str(&config)?;
+        let model = t5::T5EncoderModel::load(vb, &config)?;
+
+        let tokenizer_filename = api
+            .model("lmz/mt5-tokenizers".to_string())
+            .get("t5-v1_1-xxl.tokenizer.json")?;
+
+        let tokenizer = Tokenizer::from_file(tokenizer_filename).map_err(E::msg)?;
+        Ok(Self {
+            t5: model,
+            tokenizer,
+            max_position_embeddings,
+        })
+    }
+
+    fn encode_text_to_embedding(
+        &mut self,
+        prompt: &str,
+        device: &candle::Device,
+    ) -> Result<Tensor> {
+        let mut tokens = self
+            .tokenizer
+            .encode(prompt, true)
+            .map_err(E::msg)?
+            .get_ids()
+            .to_vec();
+        tokens.resize(self.max_position_embeddings, 0);
+        let input_token_ids = Tensor::new(&tokens[..], device)?.unsqueeze(0)?;
+        let embeddings = self.t5.forward(&input_token_ids)?;
+        Ok(embeddings)
+    }
+}
+
+pub struct StableDiffusion3TripleClipWithTokenizer {
+    clip_l: ClipWithTokenizer,
+    clip_g: ClipWithTokenizer,
+    clip_g_text_projection: candle_nn::Linear,
+    t5: T5WithTokenizer,
+}
+
+impl StableDiffusion3TripleClipWithTokenizer {
+    pub fn new(vb_fp16: candle_nn::VarBuilder, vb_fp32: candle_nn::VarBuilder) -> Result<Self> {
+        let max_position_embeddings = 77usize;
+        let clip_l = ClipWithTokenizer::new(
+            vb_fp16.pp("clip_l.transformer"),
+            stable_diffusion::clip::Config::sdxl(),
+            "openai/clip-vit-large-patch14",
+            max_position_embeddings,
+        )?;
+
+        let clip_g = ClipWithTokenizer::new(
+            vb_fp16.pp("clip_g.transformer"),
+            stable_diffusion::clip::Config::sdxl2(),
+            "laion/CLIP-ViT-bigG-14-laion2B-39B-b160k",
+            max_position_embeddings,
+        )?;
+
+        let text_projection = candle_nn::linear_no_bias(
+            1280,
+            1280,
+            vb_fp16.pp("clip_g.transformer.text_projection"),
+        )?;
+
+        // Current T5 implementation does not support fp16, so we use fp32 VarBuilder for T5.
+        // This is a temporary workaround until the T5 implementation is updated to support fp16.
+        // Also see:
+        // https://github.com/huggingface/candle/issues/2480
+        // https://github.com/huggingface/candle/pull/2481
+        let t5 = T5WithTokenizer::new(vb_fp32.pp("t5xxl.transformer"), max_position_embeddings)?;
+
+        Ok(Self {
+            clip_l,
+            clip_g,
+            clip_g_text_projection: text_projection,
+            t5,
+        })
+    }
+
+    pub fn encode_text_to_embedding(
+        &mut self,
+        prompt: &str,
+        device: &candle::Device,
+    ) -> Result<(Tensor, Tensor)> {
+        let (clip_l_embeddings, clip_l_embeddings_pooled) =
+            self.clip_l.encode_text_to_embedding(prompt, device)?;
+        let (clip_g_embeddings, clip_g_embeddings_pooled) =
+            self.clip_g.encode_text_to_embedding(prompt, device)?;
+
+        let clip_g_embeddings_pooled = self
+            .clip_g_text_projection
+            .forward(&clip_g_embeddings_pooled.unsqueeze(0)?)?
+            .squeeze(0)?;
+
+        let y = Tensor::cat(&[&clip_l_embeddings_pooled, &clip_g_embeddings_pooled], 0)?
+            .unsqueeze(0)?;
+        let clip_embeddings_concat = Tensor::cat(
+            &[&clip_l_embeddings, &clip_g_embeddings],
+            D::Minus1,
+        )?
+        .pad_with_zeros(D::Minus1, 0, 2048)?;
+
+        let t5_embeddings = self
+            .t5
+            .encode_text_to_embedding(prompt, device)?
+            .to_dtype(DType::F16)?;
+        let context = Tensor::cat(&[&clip_embeddings_concat, &t5_embeddings], D::Minus2)?;
+
+        Ok((context, y))
+    }
+}