From 01b955ac3dad2ae8e49bd8edfca8e75b110327d7 Mon Sep 17 00:00:00 2001
From: Yuhao Yang <47235274+yhyang201@users.noreply.github.com>
Date: Mon, 15 Dec 2025 16:17:10 +0800
Subject: [PATCH] [diffusion] model: support mutli-image input and
 qwen-image-edit-2509 (#15005)

---
 .../configs/pipeline_configs/base.py          |   8 +-
 .../configs/pipeline_configs/qwen_image.py    | 139 ++++++++++++-
 .../configs/sample/qwenimage.py               |   8 +
 python/sglang/multimodal_gen/registry.py      |  12 +-
 .../runtime/entrypoints/openai/image_api.py   |  21 +-
 .../runtime/pipelines/qwen_image.py           |  24 ++-
 .../runtime/pipelines_core/schedule_batch.py  |   1 +
 .../pipelines_core/stages/denoising.py        |   2 +
 .../pipelines_core/stages/image_encoding.py   | 159 +++++++--------
 .../pipelines_core/stages/input_validation.py | 100 ++++++----
 .../test/server/perf_baselines.json           | 182 ++++++++++++------
 .../test/server/test_server_common.py         |  20 +-
 .../test/server/test_server_utils.py          |  52 +++--
 .../test/server/testcase_configs.py           |  18 ++
 .../sglang/multimodal_gen/test/slack_utils.py |  52 +++--
 15 files changed, 577 insertions(+), 221 deletions(-)

diff --git a/python/sglang/multimodal_gen/configs/pipeline_configs/base.py b/python/sglang/multimodal_gen/configs/pipeline_configs/base.py
index c363d00b7..816f1765d 100644
--- a/python/sglang/multimodal_gen/configs/pipeline_configs/base.py
+++ b/python/sglang/multimodal_gen/configs/pipeline_configs/base.py
@@ -208,7 +208,10 @@ class PipelineConfig:
             (target_width, target_height), PIL.Image.Resampling.LANCZOS
         ), (target_width, target_height)
 
-    def prepare_image_processor_kwargs(self, batch):
+    def prepare_calculated_size(self, image):
+        return self.calculate_condition_image_size(image, image.width, image.height)
+
+    def prepare_image_processor_kwargs(self, batch, neg=False):
         return {}
 
     def postprocess_image_latent(self, latent_condition, batch):
@@ -297,6 +300,9 @@ class PipelineConfig:
         latents = sequence_model_parallel_all_gather(latents, dim=2)
         return latents
 
+    def preprocess_vae_image(self, batch, vae_image_processor):
+        pass
+
     def shard_latents_for_sp(self, batch, latents):
         # general logic for video models
         sp_world_size, rank_in_sp_group = get_sp_world_size(), get_sp_parallel_rank()
diff --git a/python/sglang/multimodal_gen/configs/pipeline_configs/qwen_image.py b/python/sglang/multimodal_gen/configs/pipeline_configs/qwen_image.py
index 035c71e0b..493cd5ee6 100644
--- a/python/sglang/multimodal_gen/configs/pipeline_configs/qwen_image.py
+++ b/python/sglang/multimodal_gen/configs/pipeline_configs/qwen_image.py
@@ -107,8 +107,9 @@ class QwenImagePipelineConfig(ImagePipelineConfig):
     def prepare_sigmas(self, sigmas, num_inference_steps):
         return self._prepare_sigmas(sigmas, num_inference_steps)
 
-    def prepare_image_processor_kwargs(self, batch):
-        if batch.prompt:
+    def prepare_image_processor_kwargs(self, batch, neg=False):
+        prompt = batch.prompt if not neg else batch.negative_prompt
+        if prompt:
             prompt_template_encode = "<|im_start|>system\nDescribe the key features of the input image (color, shape, size, texture, objects, background), then explain how the user's text instruction should alter or modify the image. Generate a new image that meets the user's requirements while maintaining consistency with the original input where appropriate.<|im_end|>\n<|im_start|>user\n<|vision_start|><|image_pad|><|vision_end|>{}<|im_end|>\n<|im_start|>assistant\n"
             txt = prompt_template_encode.format(batch.prompt)
             return dict(text=[txt], padding=True)
@@ -328,3 +329,137 @@ class QwenImageEditPipelineConfig(QwenImagePipelineConfig):
         # remove noise over input image
         noise = noise[:, : latents.size(1)]
         return noise
+
+
+CONDITION_IMAGE_SIZE = 384 * 384
+VAE_IMAGE_SIZE = 1024 * 1024
+
+
+@dataclass
+class QwenImageEditPlusPipelineConfig(QwenImageEditPipelineConfig):
+    task_type: ModelTaskType = ModelTaskType.I2I
+
+    def _get_condition_image_sizes(self, batch) -> list[tuple[int, int]]:
+        image = batch.condition_image
+        if not isinstance(image, list):
+            image = [image]
+
+        condition_image_sizes = []
+        for img in image:
+            image_width, image_height = img.size
+            edit_width, edit_height, _ = calculate_dimensions(
+                VAE_IMAGE_SIZE, image_width / image_height
+            )
+            condition_image_sizes.append((edit_width, edit_height))
+
+        return condition_image_sizes
+
+    def prepare_image_processor_kwargs(self, batch, neg=False) -> dict:
+        prompt = batch.prompt if not neg else batch.negative_prompt
+        prompt_list = [prompt] if isinstance(prompt, str) else prompt
+        image_list = batch.condition_image
+
+        prompt_template_encode = (
+            "<|im_start|>system\nDescribe the key features of the input image "
+            "(color, shape, size, texture, objects, background), then explain how "
+            "the user's text instruction should alter or modify the image. Generate "
+            "a new image that meets the user's requirements while maintaining "
+            "consistency with the original input where appropriate.<|im_end|>\n"
+            "<|im_start|>user\n{}<|im_end|>\n"
+            "<|im_start|>assistant\n"
+        )
+        img_prompt_template = "Picture {}: <|vision_start|><|image_pad|><|vision_end|>"
+        if isinstance(image_list, list):
+            base_img_prompt = ""
+            for i, img in enumerate(image_list):
+                base_img_prompt += img_prompt_template.format(i + 1)
+        txt = [prompt_template_encode.format(base_img_prompt + p) for p in prompt_list]
+        return dict(text=txt, padding=True)
+
+    def prepare_calculated_size(self, image):
+        return self.calculate_vae_image_size(image, image.width, image.height)
+
+    def resize_condition_image(self, images, target_width, target_height):
+        if not isinstance(images, list):
+            images = [images]
+        new_images = []
+        for img, width, height in zip(images, target_width, target_height):
+            new_images.append(resize(img, height, width, resize_mode="default"))
+        return new_images
+
+    def calculate_condition_image_size(self, image, width, height) -> tuple[int, int]:
+        calculated_width, calculated_height, _ = calculate_dimensions(
+            CONDITION_IMAGE_SIZE, width / height
+        )
+        return calculated_width, calculated_height
+
+    def calculate_vae_image_size(self, image, width, height) -> tuple[int, int]:
+        calculated_width, calculated_height, _ = calculate_dimensions(
+            VAE_IMAGE_SIZE, width / height
+        )
+        return calculated_width, calculated_height
+
+    def preprocess_vae_image(self, batch, vae_image_processor):
+        if not isinstance(batch.condition_image, list):
+            batch.condition_image = [batch.condition_image]
+        new_images = []
+        vae_image_sizes = []
+        for img in batch.condition_image:
+            width, height = self.calculate_vae_image_size(img, img.width, img.height)
+            new_images.append(vae_image_processor.preprocess(img, height, width))
+            vae_image_sizes.append((width, height))
+        batch.vae_image = new_images
+        batch.vae_image_sizes = vae_image_sizes
+        return batch
+
+    def _prepare_edit_cond_kwargs(
+        self, batch, prompt_embeds, rotary_emb, device, dtype
+    ):
+        batch_size = batch.latents.shape[0]
+        assert batch_size == 1
+        height = batch.height
+        width = batch.width
+        image_size = batch.original_condition_image_size
+
+        vae_scale_factor = self.get_vae_scale_factor()
+
+        img_shapes = [
+            [
+                (1, height // vae_scale_factor // 2, width // vae_scale_factor // 2),
+                *[
+                    (
+                        1,
+                        vae_height // vae_scale_factor // 2,
+                        vae_width // vae_scale_factor // 2,
+                    )
+                    for vae_width, vae_height in batch.vae_image_sizes
+                ],
+            ],
+        ] * batch_size
+        txt_seq_lens = [prompt_embeds[0].shape[1]]
+
+        (img_cos, img_sin), (txt_cos, txt_sin) = (
+            QwenImageEditPlusPipelineConfig.get_freqs_cis(
+                img_shapes, txt_seq_lens, rotary_emb, device, dtype
+            )
+        )
+
+        # perform sp shard on noisy image tokens
+        noisy_img_seq_len = (
+            1 * (height // vae_scale_factor // 2) * (width // vae_scale_factor // 2)
+        )
+        noisy_img_cos = shard_rotary_emb_for_sp(img_cos[:noisy_img_seq_len, :])
+        noisy_img_sin = shard_rotary_emb_for_sp(img_sin[:noisy_img_seq_len, :])
+
+        # concat back the img_cos for input image (since it is not sp-shared later)
+        img_cos = torch.cat([noisy_img_cos, img_cos[noisy_img_seq_len:, :]], dim=0).to(
+            device=device
+        )
+        img_sin = torch.cat([noisy_img_sin, img_sin[noisy_img_seq_len:, :]], dim=0).to(
+            device=device
+        )
+
+        return {
+            "txt_seq_lens": txt_seq_lens,
+            "freqs_cis": ((img_cos, img_sin), (txt_cos, txt_sin)),
+        }
diff --git a/python/sglang/multimodal_gen/configs/sample/qwenimage.py b/python/sglang/multimodal_gen/configs/sample/qwenimage.py
index 9bec1b172..c043f328b 100644
--- a/python/sglang/multimodal_gen/configs/sample/qwenimage.py
+++ b/python/sglang/multimodal_gen/configs/sample/qwenimage.py
@@ -13,3 +13,11 @@ class QwenImageSamplingParams(SamplingParams):
     # Denoising stage
     guidance_scale: float = 4.0
     num_inference_steps: int = 50
+
+
+@dataclass
+class QwenImageEditPlusSamplingParams(QwenImageSamplingParams):
+    # Denoising stage
+    guidance_scale: float = 4.0
+    # true_cfg_scale: float = 4.0
+    num_inference_steps: int = 40
diff --git a/python/sglang/multimodal_gen/registry.py b/python/sglang/multimodal_gen/registry.py
index 1211d8981..c3c8ede37 100644
--- a/python/sglang/multimodal_gen/registry.py
+++ b/python/sglang/multimodal_gen/registry.py
@@ -29,6 +29,7 @@ from sglang.multimodal_gen.configs.pipeline_configs.base import PipelineConfig
 from sglang.multimodal_gen.configs.pipeline_configs.flux import Flux2PipelineConfig
 from sglang.multimodal_gen.configs.pipeline_configs.qwen_image import (
     QwenImageEditPipelineConfig,
+    QwenImageEditPlusPipelineConfig,
     QwenImagePipelineConfig,
 )
 from sglang.multimodal_gen.configs.pipeline_configs.wan import (
@@ -43,7 +44,10 @@ from sglang.multimodal_gen.configs.sample.hunyuan import (
     FastHunyuanSamplingParam,
     HunyuanSamplingParams,
 )
-from sglang.multimodal_gen.configs.sample.qwenimage import QwenImageSamplingParams
+from sglang.multimodal_gen.configs.sample.qwenimage import (
+    QwenImageEditPlusSamplingParams,
+    QwenImageSamplingParams,
+)
 from sglang.multimodal_gen.configs.sample.stepvideo import StepVideoT2VSamplingParams
 from sglang.multimodal_gen.configs.sample.wan import (
     FastWanT2V480PConfig,
@@ -427,5 +431,11 @@ def _register_configs():
         hf_model_paths=["Qwen/Qwen-Image-Edit"],
     )
 
+    register_configs(
+        sampling_param_cls=QwenImageEditPlusSamplingParams,
+        pipeline_config_cls=QwenImageEditPlusPipelineConfig,
+        hf_model_paths=["Qwen/Qwen-Image-Edit-2509"],
+    )
+
 
 _register_configs()
diff --git a/python/sglang/multimodal_gen/runtime/entrypoints/openai/image_api.py b/python/sglang/multimodal_gen/runtime/entrypoints/openai/image_api.py
index 7df023243..1ac397f1c 100644
--- a/python/sglang/multimodal_gen/runtime/entrypoints/openai/image_api.py
+++ b/python/sglang/multimodal_gen/runtime/entrypoints/openai/image_api.py
@@ -82,14 +82,18 @@ def _build_sampling_params_from_request(
 
 
 def _build_req_from_sampling(s: SamplingParams) -> Req:
+    # TODO: refactor this! this is so dangerous because we could forget to add a new field here!
     return Req(
         request_id=s.request_id,
         data_type=s.data_type,
         prompt=s.prompt,
+        negative_prompt=s.negative_prompt,
         image_path=s.image_path,
         height=s.height,
         width=s.width,
         fps=1,
+        guidance_scale=s.guidance_scale,
+        num_inference_steps=s.num_inference_steps,
         num_frames=s.num_frames,
         seed=s.seed,
         generator_device=s.generator_device,
@@ -172,12 +176,17 @@ async def edits(
     if not images or len(images) == 0:
         raise HTTPException(status_code=422, detail="Field 'image' is required")
 
-    # Save first input image; additional images or mask are not yet used by the pipeline
+    # Save all input images; additional images beyond the first are saved for potential future use
     uploads_dir = os.path.join("outputs", "uploads")
     os.makedirs(uploads_dir, exist_ok=True)
-    first_image = images[0]
-    input_path = os.path.join(uploads_dir, f"{request_id}_{first_image.filename}")
-    await _save_upload_to_path(first_image, input_path)
+    if images is not None and not isinstance(images, list):
+        images = [images]
+    input_paths = []
+    for idx, img in enumerate(images):
+        filename = img.filename or f"image_{idx}"
+        input_path = os.path.join(uploads_dir, f"{request_id}_{idx}_{filename}")
+        await _save_upload_to_path(img, input_path)
+        input_paths.append(input_path)
 
     sampling = _build_sampling_params_from_request(
         request_id=request_id,
@@ -186,7 +195,7 @@ async def edits(
         size=size,
         output_format=output_format,
         background=background,
-        image_path=input_path,
+        image_path=input_paths,
         seed=seed,
         generator_device=generator_device,
     )
@@ -200,6 +209,8 @@ async def edits(
             "id": request_id,
             "created_at": int(time.time()),
             "file_path": save_file_path,
+            "input_image_paths": input_paths,  # Store all input image paths
+            "num_input_images": len(input_paths),
         },
     )
 
diff --git a/python/sglang/multimodal_gen/runtime/pipelines/qwen_image.py b/python/sglang/multimodal_gen/runtime/pipelines/qwen_image.py
index fabaae54b..d08c6ed37 100644
--- a/python/sglang/multimodal_gen/runtime/pipelines/qwen_image.py
+++ b/python/sglang/multimodal_gen/runtime/pipelines/qwen_image.py
@@ -1,6 +1,7 @@
 # Copied and adapted from: https://github.com/hao-ai-lab/FastVideo
 
 # SPDX-License-Identifier: Apache-2.0
+from diffusers.image_processor import VaeImageProcessor
 
 from sglang.multimodal_gen.runtime.pipelines_core import LoRAPipeline
 from sglang.multimodal_gen.runtime.pipelines_core.composed_pipeline_base import (
@@ -45,15 +46,16 @@ def prepare_mu(batch: Req, server_args: ServerArgs):
     height = batch.height
     width = batch.width
     vae_scale_factor = server_args.pipeline_config.vae_config.vae_scale_factor
-    image_seq_len = (int(height) // vae_scale_factor) * (int(width) // vae_scale_factor)
-
+    image_seq_len = (int(height) // vae_scale_factor // 2) * (
+        int(width) // vae_scale_factor // 2
+    )
     mu = calculate_shift(
         image_seq_len,
         # hard code, since scheduler_config is not in PipelineConfig now
         256,
-        4096,
+        8192,
         0.5,
-        1.15,
+        0.9,
     )
     return "mu", mu
 
@@ -135,7 +137,13 @@ class QwenImageEditPipeline(LoRAPipeline, ComposedPipelineBase):
         """Set up pipeline stages with proper dependency injection."""
 
         self.add_stage(
-            stage_name="input_validation_stage", stage=InputValidationStage()
+            stage_name="input_validation_stage",
+            stage=InputValidationStage(
+                vae_image_processor=VaeImageProcessor(
+                    vae_scale_factor=server_args.pipeline_config.vae_config.arch_config.vae_scale_factor
+                    * 2
+                )
+            ),
         )
 
         self.add_stage(
@@ -184,4 +192,8 @@ class QwenImageEditPipeline(LoRAPipeline, ComposedPipelineBase):
         )
 
 
-EntryClass = [QwenImagePipeline, QwenImageEditPipeline]
+class QwenImageEditPlusPipeline(QwenImageEditPipeline):
+    pipeline_name = "QwenImageEditPlusPipeline"
+
+
+EntryClass = [QwenImagePipeline, QwenImageEditPipeline, QwenImageEditPlusPipeline]
diff --git a/python/sglang/multimodal_gen/runtime/pipelines_core/schedule_batch.py b/python/sglang/multimodal_gen/runtime/pipelines_core/schedule_batch.py
index ef871b1cc..e962c21ba 100644
--- a/python/sglang/multimodal_gen/runtime/pipelines_core/schedule_batch.py
+++ b/python/sglang/multimodal_gen/runtime/pipelines_core/schedule_batch.py
@@ -57,6 +57,7 @@ class Req:
 
     original_condition_image_size: tuple[int, int] = None
     condition_image: torch.Tensor | PIL.Image.Image | None = None
+    vae_image: torch.Tensor | PIL.Image.Image | None = None
     pixel_values: torch.Tensor | PIL.Image.Image | None = None
     preprocessed_image: torch.Tensor | None = None
 
diff --git a/python/sglang/multimodal_gen/runtime/pipelines_core/stages/denoising.py b/python/sglang/multimodal_gen/runtime/pipelines_core/stages/denoising.py
index 89f206d45..ac1b40bb1 100755
--- a/python/sglang/multimodal_gen/runtime/pipelines_core/stages/denoising.py
+++ b/python/sglang/multimodal_gen/runtime/pipelines_core/stages/denoising.py
@@ -933,6 +933,8 @@ class DenoisingStage(PipelineStage):
         denoising_start_time = time.time()
 
         # to avoid device-sync caused by timestep comparison
+
+        self.scheduler.set_begin_index(0)
         timesteps_cpu = timesteps.cpu()
         num_timesteps = timesteps_cpu.shape[0]
         with torch.autocast(
diff --git a/python/sglang/multimodal_gen/runtime/pipelines_core/stages/image_encoding.py b/python/sglang/multimodal_gen/runtime/pipelines_core/stages/image_encoding.py
index 5264c1b0e..a86db6b46 100644
--- a/python/sglang/multimodal_gen/runtime/pipelines_core/stages/image_encoding.py
+++ b/python/sglang/multimodal_gen/runtime/pipelines_core/stages/image_encoding.py
@@ -121,12 +121,11 @@ class ImageEncodingStage(PipelineStage):
         elif self.text_encoder:
             # if a text encoder is provided, e.g. Qwen-Image-Edit
             # 1. neg prompt embeds
-            if batch.prompt:
-                prompt_template_encode = "<|im_start|>system\nDescribe the key features of the input image (color, shape, size, texture, objects, background), then explain how the user's text instruction should alter or modify the image. Generate a new image that meets the user's requirements while maintaining consistency with the original input where appropriate.<|im_end|>\n<|im_start|>user\n<|vision_start|><|image_pad|><|vision_end|>{}<|im_end|>\n<|im_start|>assistant\n"
-                txt = prompt_template_encode.format(batch.negative_prompt)
-                neg_image_processor_kwargs = dict(text=[txt], padding=True)
-            else:
-                neg_image_processor_kwargs = {}
+            neg_image_processor_kwargs = (
+                server_args.pipeline_config.prepare_image_processor_kwargs(
+                    batch, neg=True
+                )
+            )
 
             neg_image_inputs = self.image_processor(
                 images=image, return_tensors="pt", **neg_image_processor_kwargs
@@ -211,89 +210,98 @@ class ImageVAEEncodingStage(PipelineStage):
 
         self.vae = self.vae.to(get_local_torch_device())
 
-        image = batch.condition_image
-        image = self.preprocess(
-            image,
-        ).to(get_local_torch_device(), dtype=torch.float32)
-
-        # (B, C, H, W) -> (B, C, 1, H, W)
-        image = image.unsqueeze(2)
-
-        if num_frames == 1:
-            video_condition = image
-        else:
-            video_condition = torch.cat(
-                [
-                    image,
-                    image.new_zeros(
-                        image.shape[0],
-                        image.shape[1],
-                        num_frames - 1,
-                        image.shape[3],
-                        image.shape[4],
-                    ),
-                ],
-                dim=2,
-            )
-        video_condition = video_condition.to(
-            device=get_local_torch_device(), dtype=torch.float32
+        images = (
+            batch.vae_image if batch.vae_image is not None else batch.condition_image
         )
+        if not isinstance(images, list):
+            images = [images]
 
-        # Setup VAE precision
-        vae_dtype = PRECISION_TO_TYPE[server_args.pipeline_config.vae_precision]
-        vae_autocast_enabled = (
-            vae_dtype != torch.float32
-        ) and not server_args.disable_autocast
+        all_image_latents = []
+        for image in images:
+            image = self.preprocess(
+                image,
+            ).to(get_local_torch_device(), dtype=torch.float32)
 
-        # Encode Image
-        with torch.autocast(
-            device_type="cuda", dtype=vae_dtype, enabled=vae_autocast_enabled
-        ):
-            if server_args.pipeline_config.vae_tiling:
-                self.vae.enable_tiling()
-            # if server_args.vae_sp:
-            #     self.vae.enable_parallel()
-            if not vae_autocast_enabled:
-                video_condition = video_condition.to(vae_dtype)
-            encoder_output: DiagonalGaussianDistribution = self.vae.encode(
-                video_condition
+            # (B, C, H, W) -> (B, C, 1, H, W)
+            image = image.unsqueeze(2)
+
+            if num_frames == 1:
+                video_condition = image
+            else:
+                video_condition = torch.cat(
+                    [
+                        image,
+                        image.new_zeros(
+                            image.shape[0],
+                            image.shape[1],
+                            num_frames - 1,
+                            image.shape[3],
+                            image.shape[4],
+                        ),
+                    ],
+                    dim=2,
+                )
+            video_condition = video_condition.to(
+                device=get_local_torch_device(), dtype=torch.float32
             )
 
-        generator = batch.generator
-        if generator is None:
-            raise ValueError("Generator must be provided")
+            # Setup VAE precision
+            vae_dtype = PRECISION_TO_TYPE[server_args.pipeline_config.vae_precision]
+            vae_autocast_enabled = (
+                vae_dtype != torch.float32
+            ) and not server_args.disable_autocast
 
-        sample_mode = server_args.pipeline_config.vae_config.encode_sample_mode()
+            # Encode Image
+            with torch.autocast(
+                device_type="cuda", dtype=vae_dtype, enabled=vae_autocast_enabled
+            ):
+                if server_args.pipeline_config.vae_tiling:
+                    self.vae.enable_tiling()
+                # if server_args.vae_sp:
+                #     self.vae.enable_parallel()
+                if not vae_autocast_enabled:
+                    video_condition = video_condition.to(vae_dtype)
+                encoder_output: DiagonalGaussianDistribution = self.vae.encode(
+                    video_condition
+                )
 
-        latent_condition = self.retrieve_latents(
-            encoder_output, generator, sample_mode=sample_mode
-        )
-        latent_condition = server_args.pipeline_config.postprocess_vae_encode(
-            latent_condition, self.vae
-        )
+            generator = batch.generator
+            if generator is None:
+                raise ValueError("Generator must be provided")
 
-        scaling_factor, shift_factor = (
-            server_args.pipeline_config.get_decode_scale_and_shift(
-                device=latent_condition.device,
-                dtype=latent_condition.dtype,
-                vae=self.vae,
+            sample_mode = server_args.pipeline_config.vae_config.encode_sample_mode()
+
+            latent_condition = self.retrieve_latents(
+                encoder_output, generator, sample_mode=sample_mode
+            )
+            latent_condition = server_args.pipeline_config.postprocess_vae_encode(
+                latent_condition, self.vae
             )
-        )
 
-        # apply shift & scale if needed
-        if isinstance(shift_factor, torch.Tensor):
-            shift_factor = shift_factor.to(latent_condition.device)
+            scaling_factor, shift_factor = (
+                server_args.pipeline_config.get_decode_scale_and_shift(
+                    device=latent_condition.device,
+                    dtype=latent_condition.dtype,
+                    vae=self.vae,
+                )
+            )
 
-        if isinstance(scaling_factor, torch.Tensor):
-            scaling_factor = scaling_factor.to(latent_condition.device)
+            # apply shift & scale if needed
+            if isinstance(shift_factor, torch.Tensor):
+                shift_factor = shift_factor.to(latent_condition.device)
 
-        latent_condition -= shift_factor
-        latent_condition = latent_condition * scaling_factor
+            if isinstance(scaling_factor, torch.Tensor):
+                scaling_factor = scaling_factor.to(latent_condition.device)
 
-        batch.image_latent = server_args.pipeline_config.postprocess_image_latent(
-            latent_condition, batch
-        )
+            latent_condition -= shift_factor
+            latent_condition = latent_condition * scaling_factor
 
+            image_latent = server_args.pipeline_config.postprocess_image_latent(
+                latent_condition, batch
+            )
+            all_image_latents.append(image_latent)
+
+        batch.image_latent = torch.cat(all_image_latents, dim=1)
         self.maybe_free_model_hooks()
 
         self.vae.to("cpu")
@@ -337,6 +345,7 @@ class ImageVAEEncodingStage(PipelineStage):
         assert batch.condition_image is None or (
             isinstance(batch.condition_image, PIL.Image.Image)
             or isinstance(batch.condition_image, torch.Tensor)
+            or isinstance(batch.condition_image, list)
         )
         assert batch.height is not None and isinstance(batch.height, int)
         assert batch.width is not None and isinstance(batch.width, int)
diff --git a/python/sglang/multimodal_gen/runtime/pipelines_core/stages/input_validation.py b/python/sglang/multimodal_gen/runtime/pipelines_core/stages/input_validation.py
index 399721bec..8254297d9 100644
--- a/python/sglang/multimodal_gen/runtime/pipelines_core/stages/input_validation.py
+++ b/python/sglang/multimodal_gen/runtime/pipelines_core/stages/input_validation.py
@@ -80,41 +80,48 @@ class InputValidationStage(PipelineStage):
         """
         if server_args.pipeline_config.task_type == ModelTaskType.I2I:
             # calculate new condition image size
-            calculated_size = (
-                server_args.pipeline_config.calculate_condition_image_size(
-                    batch.condition_image,
-                    condition_image_width,
-                    condition_image_height,
-                )
-            )
+            if not isinstance(batch.condition_image, list):
+                batch.condition_image = [batch.condition_image]
 
-            # preprocess condition image if necessary
-            if calculated_size is not None:
-                calculated_width, calculated_height = calculated_size
-                condition_image, calculated_size = (
-                    server_args.pipeline_config.preprocess_condition_image(
-                        batch.condition_image,
-                        calculated_width,
-                        calculated_height,
-                        self.vae_image_processor,
+            processed_images = []
+            final_image = batch.condition_image[-1]
+            config = server_args.pipeline_config
+            config.preprocess_vae_image(batch, self.vae_image_processor)
+
+            for img in batch.condition_image:
+                size = config.calculate_condition_image_size(img, img.width, img.height)
+                if size is not None:
+                    width, height = size
+                    img, _ = config.preprocess_condition_image(
+                        img, width, height, self.vae_image_processor
                     )
-                )
-                batch.condition_image = condition_image
+
+                processed_images.append(img)
+
+            batch.condition_image = processed_images
+            calculated_size = config.prepare_calculated_size(final_image)
 
             # adjust output image size
-            calculated_width, calculated_height = calculated_size
-            width = batch.width or calculated_width
-            height = batch.height or calculated_height
-            multiple_of = (
-                server_args.pipeline_config.vae_config.get_vae_scale_factor() * 2
-            )
-            width = width // multiple_of * multiple_of
-            height = height // multiple_of * multiple_of
-            batch.width = width
-            batch.height = height
+            if calculated_size is not None:
+                calculated_width, calculated_height = calculated_size
+                width = batch.width or calculated_width
+                height = batch.height or calculated_height
+                multiple_of = (
+                    server_args.pipeline_config.vae_config.get_vae_scale_factor() * 2
+                )
+                width = width // multiple_of * multiple_of
+                height = height // multiple_of * multiple_of
+                batch.width = width
+                batch.height = height
+
         elif server_args.pipeline_config.task_type == ModelTaskType.TI2V:
             # duplicate with vae_image_processor
             # further processing for ti2v task
+            if isinstance(
+                batch.condition_image, list
+            ):  # not support multi image input yet.
+                batch.condition_image = batch.condition_image[0]
+
             img = batch.condition_image
             ih, iw = img.height, img.width
             patch_size = server_args.pipeline_config.dit_config.arch_config.patch_size
@@ -146,6 +153,11 @@ class InputValidationStage(PipelineStage):
         elif isinstance(server_args.pipeline_config, WanI2V480PConfig):
             # TODO: could we merge with above?
             # resize image only, Wan2.1 I2V
+            if isinstance(batch.condition_image, list):
+                batch.condition_image = batch.condition_image[
+                    0
+                ]  # not support multi image input yet.
+
             max_area = server_args.pipeline_config.max_area
             aspect_ratio = condition_image_height / condition_image_width
             mod_value = (
@@ -207,13 +219,33 @@ class InputValidationStage(PipelineStage):
         # for i2v, get image from image_path
         # @TODO(Wei) hard-coded for wan2.2 5b ti2v for now. Should put this in image_encoding stage
         if batch.image_path is not None:
-            if batch.image_path.endswith(".mp4"):
-                image = load_video(batch.image_path)[0]
+            if isinstance(batch.image_path, list):
+                batch.condition_image = []
+                for path in batch.image_path:
+                    if path.endswith(".mp4"):
+                        image = load_video(path)[0]
+                    else:
+                        image = load_image(path)
+                    batch.condition_image.append(image)
+
+                # Use the first image for size reference
+                condition_image_width = batch.condition_image[0].width
+                condition_image_height = batch.condition_image[0].height
+                batch.original_condition_image_size = (
+                    condition_image_width,
+                    condition_image_height,
+                )
             else:
-                image = load_image(batch.image_path)
-            batch.condition_image = image
-            condition_image_width, condition_image_height = image.width, image.height
-            batch.original_condition_image_size = image.size
+                if batch.image_path.endswith(".mp4"):
+                    image = load_video(batch.image_path)[0]
+                else:
+                    image = load_image(batch.image_path)
+                batch.condition_image = image
+                condition_image_width, condition_image_height = (
+                    image.width,
+                    image.height,
+                )
+                batch.original_condition_image_size = image.size
 
             self.preprocess_condition_image(
                 batch, server_args, condition_image_width, condition_image_height
diff --git a/python/sglang/multimodal_gen/test/server/perf_baselines.json b/python/sglang/multimodal_gen/test/server/perf_baselines.json
index e93a9d1e4..29951e088 100644
--- a/python/sglang/multimodal_gen/test/server/perf_baselines.json
+++ b/python/sglang/multimodal_gen/test/server/perf_baselines.json
@@ -454,72 +454,71 @@
             "expected_median_denoise_ms": 102.03
         },
         "qwen_image_edit_ti2i": {
-            "notes": "single uploaded reference image, Qwen/Qwen-Image-Edit",
-            "expected_e2e_ms": 138500.0,
-            "expected_avg_denoise_ms": 720.0,
-            "expected_median_denoise_ms": 718.0,
             "stages_ms": {
-                "InputValidationStage": 23,
-                "ImageEncodingStage": 1485.0,
-                "ImageVAEEncodingStage": 400.0,
-                "ConditioningStage": 0.13,
-                "TimestepPreparationStage": 13.78,
-                "LatentPreparationStage": 15.0,
-                "DenoisingStage": 36000.0,
-                "DecodingStage": 850.0
+                "InputValidationStage": 38.62,
+                "ImageEncodingStage": 1174.26,
+                "ImageVAEEncodingStage": 233.71,
+                "TimestepPreparationStage": 3.0,
+                "LatentPreparationStage": 0.17,
+                "ConditioningStage": 0.01,
+                "DenoisingStage": 42542.67,
+                "DecodingStage": 508.39
             },
             "denoise_step_ms": {
-                "0": 720.0,
-                "1": 720.0,
-                "2": 720.0,
-                "3": 720.0,
-                "4": 720.0,
-                "5": 720.0,
-                "6": 720.0,
-                "7": 720.0,
-                "8": 720.0,
-                "9": 720.0,
-                "10": 720.0,
-                "11": 720.0,
-                "12": 720.0,
-                "13": 720.0,
-                "14": 720.0,
-                "15": 720.0,
-                "16": 720.0,
-                "17": 720.0,
-                "18": 720.0,
-                "19": 720.0,
-                "20": 720.0,
-                "21": 720.0,
-                "22": 720.0,
-                "23": 720.0,
-                "24": 720.0,
-                "25": 720.0,
-                "26": 720.0,
-                "27": 720.0,
-                "28": 720.0,
-                "29": 720.0,
-                "30": 720.0,
-                "31": 720.0,
-                "32": 720.0,
-                "33": 720.0,
-                "34": 720.0,
-                "35": 720.0,
-                "36": 720.0,
-                "37": 720.0,
-                "38": 720.0,
-                "39": 720.0,
-                "40": 720.0,
-                "41": 720.0,
-                "42": 720.0,
-                "43": 720.0,
-                "44": 720.0,
-                "45": 720.0,
-                "46": 720.0,
-                "47": 720.0,
-                "48": 720.0,
-                "49": 720.0
-            }
+                "0": 705.2,
+                "1": 854.4,
+                "2": 853.02,
+                "3": 852.77,
+                "4": 850.58,
+                "5": 851.46,
+                "6": 850.78,
+                "7": 851.67,
+                "8": 852.81,
+                "9": 853.98,
+                "10": 853.68,
+                "11": 852.62,
+                "12": 853.78,
+                "13": 854.42,
+                "14": 853.59,
+                "15": 853.28,
+                "16": 853.58,
+                "17": 854.02,
+                "18": 854.42,
+                "19": 854.46,
+                "20": 853.6,
+                "21": 854.18,
+                "22": 854.05,
+                "23": 854.45,
+                "24": 855.4,
+                "25": 851.82,
+                "26": 855.31,
+                "27": 854.42,
+                "28": 854.2,
+                "29": 854.43,
+                "30": 855.49,
+                "31": 854.51,
+                "32": 855.26,
+                "33": 852.42,
+                "34": 853.82,
+                "35": 856.22,
+                "36": 854.53,
+                "37": 854.44,
+                "38": 854.07,
+                "39": 852.74,
+                "40": 854.56,
+                "41": 854.24,
+                "42": 853.56,
+                "43": 854.74,
+                "44": 855.34,
+                "45": 853.93,
+                "46": 854.36,
+                "47": 852.65,
+                "48": 851.19,
+                "49": 851.89
+            },
+            "expected_e2e_ms": 44503.12,
+            "expected_avg_denoise_ms": 850.73,
+            "expected_median_denoise_ms": 854.0
         },
         "wan2_1_t2v_1.3b": {
             "stages_ms": {
@@ -655,6 +654,63 @@
             "expected_avg_denoise_ms": 2608.84,
             "expected_median_denoise_ms": 2601.59
         },
+        "qwen_image_edit_2509_ti2i": {
+            "stages_ms": {
+                "InputValidationStage": 213.24,
+                "ImageEncodingStage": 1089.12,
+                "ImageVAEEncodingStage": 304.56,
+                "TimestepPreparationStage": 2.94,
+                "LatentPreparationStage": 0.2,
+                "ConditioningStage": 0.01,
+                "DenoisingStage": 50724.5,
+                "DecodingStage": 601.02
+            },
+            "denoise_step_ms": {
+                "0": 1057.09,
+                "1": 1267.06,
+                "2": 1268.33,
+                "3": 1268.94,
+                "4": 1270.36,
+                "5": 1270.44,
+                "6": 1268.61,
+                "7": 1270.21,
+                "8": 1274.98,
+                "9": 1271.57,
+                "10": 1273.15,
+                "11": 1271.56,
+                "12": 1272.69,
+                "13": 1271.62,
+                "14": 1274.04,
+                "15": 1276.81,
+                "16": 1272.2,
+                "17": 1269.33,
+                "18": 1275.96,
+                "19": 1274.43,
+                "20": 1272.57,
+                "21": 1275.28,
+                "22": 1273.63,
+                "23": 1275.06,
+                "24": 1277.39,
+                "25": 1277.27,
+                "26": 1274.74,
+                "27": 1273.38,
+                "28": 1276.77,
+                "29": 1275.59,
+                "30": 1275.51,
+                "31": 1274.9,
+                "32": 1274.8,
+                "33": 1279.03,
+                "34": 1272.9,
+                "35": 1274.67,
+                "36": 1272.61,
+                "37": 1272.82,
+                "38": 1276.41,
+                "39": 1273.55
+            },
+            "expected_e2e_ms": 52938.04,
+            "expected_avg_denoise_ms": 1267.96,
+            "expected_median_denoise_ms": 1273.46
+        },
         "fastwan2_2_ti2v_5b": {
             "stages_ms": {
                 "InputValidationStage": 88.86,
diff --git a/python/sglang/multimodal_gen/test/server/test_server_common.py b/python/sglang/multimodal_gen/test/server/test_server_common.py
index 8785e04a4..8720108bd 100644
--- a/python/sglang/multimodal_gen/test/server/test_server_common.py
+++ b/python/sglang/multimodal_gen/test/server/test_server_common.py
@@ -90,15 +90,25 @@ def diffusion_server(case: DiffusionTestCase) -> ServerContext:
             and sampling_params.image_path
         ):
             # Handle URL or local path
-            if is_image_url(sampling_params.image_path):
-                image_path = download_image_from_url(str(sampling_params.image_path))
-            else:
-                image_path = Path(sampling_params.image_path)
+            image_path_list = sampling_params.image_path
+            if not isinstance(image_path_list, list):
+                image_path_list = [image_path_list]
+
+            new_image_path_list = []
+            for image_path in image_path_list:
+                if is_image_url(image_path):
+                    new_image_path_list.append(download_image_from_url(str(image_path)))
+                else:
+                    new_image_path_list.append(Path(image_path))
+                    if not image_path.exists():
+                        pytest.skip(f"{case.id}: file missing: {image_path}")
+
+            image_path_list = new_image_path_list
 
             warmup.run_edit_warmups(
                 count=server_args.warmup_edit,
                 edit_prompt=sampling_params.prompt,
-                image_path=image_path,
+                image_path=image_path_list,
             )
     except Exception as exc:
         logger.error("Warm-up failed for %s: %s", case.id, exc)
diff --git a/python/sglang/multimodal_gen/test/server/test_server_utils.py b/python/sglang/multimodal_gen/test/server/test_server_utils.py
index 4e3e788a9..08ca84284 100644
--- a/python/sglang/multimodal_gen/test/server/test_server_utils.py
+++ b/python/sglang/multimodal_gen/test/server/test_server_utils.py
@@ -278,23 +278,31 @@ class WarmupRunner:
         if count <= 0:
             return
 
-        if not image_path.exists():
-            logger.warning(
-                "[server-test] Skipping edit warmup: image missing at %s", image_path
-            )
-            return
+        if not isinstance(image_path, list):
+            image_path = [image_path]
+
+        for image in image_path:
+            if not image.exists():
+                logger.warning(
+                    "[server-test] Skipping edit warmup: image missing at %s", image
+                )
+                return
 
         logger.info("[server-test] Running %s edit warm-up(s)", count)
         for _ in range(count):
-            with image_path.open("rb") as fh:
+            images = [open(image, "rb") for image in image_path]
+            try:
                 result = self.client.images.edit(
                     model=self.model,
-                    image=fh,
+                    image=images,
                     prompt=edit_prompt,
                     n=1,
                     size=self.output_size,
                     response_format="b64_json",
                 )
+            finally:
+                for img in images:
+                    img.close()
             validate_image(result.data[0].b64_json)
 
 
@@ -585,22 +593,36 @@ def get_generate_fn(
         if not sampling_params.prompt or not sampling_params.image_path:
             pytest.skip(f"{id}: no edit config")
 
-        if is_image_url(sampling_params.image_path):
-            image_path = download_image_from_url(str(sampling_params.image_path))
-        else:
-            image_path = Path(sampling_params.image_path)
-            if not image_path.exists():
-                pytest.skip(f"{id}: file missing: {image_path}")
+        image_paths = sampling_params.image_path
 
-        with image_path.open("rb") as fh:
+        if not isinstance(image_paths, list):
+            image_paths = [image_paths]
+
+        new_image_paths = []
+        for image_path in image_paths:
+            if is_image_url(image_path):
+                new_image_paths.append(download_image_from_url(str(image_path)))
+            else:
+                new_image_paths.append(Path(image_path))
+                if not image_path.exists():
+                    pytest.skip(f"{id}: file missing: {image_path}")
+
+        image_paths = new_image_paths
+
+        images = [open(image_path, "rb") for image_path in image_paths]
+        try:
             response = client.images.with_raw_response.edit(
                 model=model_path,
-                image=fh,
+                image=images,
                 prompt=sampling_params.prompt,
                 n=1,
                 size=sampling_params.output_size,
                 response_format="b64_json",
             )
+        finally:
+            for img in images:
+                img.close()
+
         rid = response.headers.get("x-request-id", "")
 
         result = response.parse()
diff --git a/python/sglang/multimodal_gen/test/server/testcase_configs.py b/python/sglang/multimodal_gen/test/server/testcase_configs.py
index 49e72b72d..4c8845a73 100644
--- a/python/sglang/multimodal_gen/test/server/testcase_configs.py
+++ b/python/sglang/multimodal_gen/test/server/testcase_configs.py
@@ -226,6 +226,14 @@ TI2I_sampling_params = DiffusionSamplingParams(
     image_path="https://github.com/lm-sys/lm-sys.github.io/releases/download/test/TI2I_Qwen_Image_Edit_Input.jpg",
 )
 
+MULTI_IMAGE_TI2I_sampling_params = DiffusionSamplingParams(
+    prompt="The magician bear is on the left, the alchemist bear is on the right, facing each other in the central park square.",
+    image_path=[
+        "https://qianwen-res.oss-cn-beijing.aliyuncs.com/Qwen-Image/edit2509/edit2509_1.jpg",
+        "https://qianwen-res.oss-cn-beijing.aliyuncs.com/Qwen-Image/edit2509/edit2509_2.jpg",
+    ],
+)
+
 T2V_PROMPT = "A curious raccoon"
 
 TI2V_sampling_params = DiffusionSamplingParams(
@@ -288,6 +296,16 @@ ONE_GPU_CASES_A: list[DiffusionTestCase] = [
         ),
         TI2I_sampling_params,
     ),
+    DiffusionTestCase(
+        "qwen_image_edit_2509_ti2i",
+        DiffusionServerArgs(
+            model_path="Qwen/Qwen-Image-Edit-2509",
+            modality="image",
+            warmup_text=0,
+            warmup_edit=1,
+        ),
+        MULTI_IMAGE_TI2I_sampling_params,
+    ),
 ]
 
 ONE_GPU_CASES_B: list[DiffusionTestCase] = [
diff --git a/python/sglang/multimodal_gen/test/slack_utils.py b/python/sglang/multimodal_gen/test/slack_utils.py
index 706197be3..3dafbdafc 100644
--- a/python/sglang/multimodal_gen/test/slack_utils.py
+++ b/python/sglang/multimodal_gen/test/slack_utils.py
@@ -6,6 +6,7 @@ import logging
 import os
 import tempfile
 from datetime import datetime
+from typing import List, Union
 from urllib.parse import urlparse
 from urllib.request import urlopen
 
@@ -100,9 +101,9 @@ def upload_file_to_slack(
     model: str = None,
     prompt: str = None,
     file_path: str = None,
-    origin_file_path: str = None,
+    origin_file_path: Union[str, List[str]] = None,
 ) -> bool:
-    temp_path = None
+    temp_paths = []
     try:
         from slack_sdk import WebClient
 
@@ -117,17 +118,39 @@ def upload_file_to_slack(
             logger.info(f"Slack upload failed: no file path")
             return False
 
-        if origin_file_path and origin_file_path.startswith(("http", "https")):
-            suffix = os.path.splitext(urlparse(origin_file_path).path)[1] or ".tmp"
-            with tempfile.NamedTemporaryFile(delete=False, suffix=suffix) as tf:
-                with urlopen(origin_file_path) as response:
-                    tf.write(response.read())
-                temp_path = tf.name
-                origin_file_path = temp_path
+        origin_paths = []
+        if isinstance(origin_file_path, str):
+            if origin_file_path:
+                origin_paths.append(origin_file_path)
+        elif isinstance(origin_file_path, list):
+            origin_paths = [p for p in origin_file_path if p]
 
-        uploads = [{"file": file_path, "title": "Generated Image"}]
-        if origin_file_path and os.path.exists(origin_file_path):
-            uploads.insert(0, {"file": origin_file_path, "title": "Original Image"})
+        final_origin_paths = []
+        for path in origin_paths:
+            if path.startswith(("http", "https")):
+                try:
+                    suffix = os.path.splitext(urlparse(path).path)[1] or ".tmp"
+                    with tempfile.NamedTemporaryFile(delete=False, suffix=suffix) as tf:
+                        with urlopen(path) as response:
+                            tf.write(response.read())
+                    temp_paths.append(tf.name)
+                    final_origin_paths.append(tf.name)
+                except Exception as e:
+                    logger.warning(f"Failed to download {path}: {e}")
+            else:
+                final_origin_paths.append(path)
+
+        uploads = []
+        for i, path in enumerate(final_origin_paths):
+            if os.path.exists(path):
+                title = (
+                    "Original Image"
+                    if len(final_origin_paths) == 1
+                    else f"Original Image {i+1}"
+                )
+                uploads.append({"file": path, "title": title})
+
+        uploads.append({"file": file_path, "title": "Generated Image"})
 
         message = (
             f"*Case ID:* `{case_id}`\n" f"*Model:* `{model}`\n" f"*Prompt:* {prompt}"
@@ -189,5 +212,6 @@ def upload_file_to_slack(
         logger.info(f"Slack upload failed: {e}")
         return False
     finally:
-        if temp_path and os.path.exists(temp_path):
-            os.remove(temp_path)
+        for p in temp_paths:
+            if os.path.exists(p):
+                os.remove(p)