[Bugfix][Multimodal] Fix Qwen3-Omni use_audio_in_video with mixed image/video inputs

[wendadawen]

Purpose

Fix three bugs in Qwen3-Omni multimodal input validation when use_audio_in_video=True:

1. Single video + image inputs (V+I, I+V) crashed EngineCore because the deepstack interleaved branch only treated video positions as vision positions and missed image positions.
2. Interleaved embedding merge inferred modality from token counts and could misclassify image embeddings as video in mixed image/video/audio inputs.
3. Interleaved detection required all video/audio tokens to form one globally dense range, which misclassified multi-video inputs because of boundary tokens between videos.

Changes

• Add image token mask in the interleaved branch so both image and video positions are treated as vision positions (is_vision = is_video | is_image).
• Record the true modality of each gathered embedding from mm_feature.modality in _gather_mm_embeddings() and split embeddings by explicit modality in merge_interleaved_embeddings() instead of guessing from token counts.
• Check each contiguous V/A span independently in check_interleaved_audio_video() instead of relying on a single global range.

Test Plan

Ran a test matrix covering V+I, I+V, multi-video, image+video mixed, and use_audio_in_video=False control cases against a local Qwen3-Omni deployment. All single video + image cases that previously crashed EngineCore now pass.

---

Test Code

#!/usr/bin/env python3
"""Qwen3-Omni use_audio_in_video input combination test.

Usage: python3 input_test.py [BASE_URL]
Default BASE_URL = http://127.0.0.1:8080/v1
"""
import json
import os
import sys
import time

import requests
from openai import OpenAI

# ============================================================
# Configuration
# ============================================================
BASE_URL = sys.argv[1] if len(sys.argv) > 1 else "http://127.0.0.1:8080/v1"
DATA_DIR = "/dockerdata/wendadawen/infer_demo_package/qwen3-omni_test/data"
RESULTS = "/dockerdata/wendadawen/infer_demo_package/qwen3-omni_test/results/results.jsonl"

IMAGE1 = f"{DATA_DIR}/image1.jpg"
IMAGE2 = f"{DATA_DIR}/image2.jpg"
VIDEO1 = f"{DATA_DIR}/video1.mp4"
VIDEO2 = f"{DATA_DIR}/video2.mp4"
AUDIO = f"{DATA_DIR}/audio.wav"

# ============================================================
# Setup
# ============================================================
client = OpenAI(base_url=BASE_URL, api_key="not-needed")
model = client.models.list().data[0].id
print(f"Model: {model}\nEndpoint: {BASE_URL}\n")

IMG1 = {"type": "image_url", "image_url": {"url": f"file://{IMAGE1}"}}
IMG2 = {"type": "image_url", "image_url": {"url": f"file://{IMAGE2}"}}
VID1 = {"type": "video_url", "video_url": {"url": f"file://{VIDEO1}"}}
VID2 = {"type": "video_url", "video_url": {"url": f"file://{VIDEO2}"}}
AUD  = {"type": "audio_url", "audio_url": {"url": f"file://{AUDIO}"}}
TXT  = {"type": "text", "text": "Please describe the content."}

TOOL_SEARCH = {
    "id": "call_1",
    "type": "function",
    "function": {
        "name": "video_keyframe_search",
        "arguments": '{"query_frame_list": [{"query": "identify", "frame_idx": 3}]}',
    },
}


def alive():
    try:
        requests.get(f"{BASE_URL}/models", timeout=3)
        return True
    except Exception:
        return False


def user(*blocks):
    return {"role": "user", "content": list(blocks)}


def assistant(*tool_calls):
    return {"role": "assistant", "content": "", "tool_calls": list(tool_calls)}


def tool(call_id, name, content):
    return {"role": "tool", "tool_call_id": call_id, "name": name, "content": content}


def request(case_id, desc, messages, use_audio):
    rec = {"case_id": case_id, "desc": desc, "success": False}
    try:
        mm = {"max_pixels": 102400, "min_pixels": 3136, "use_audio_in_video": use_audio}
        r = client.chat.completions.create(
            model=model,
            messages=messages,
            max_tokens=1024,
            temperature=0,
            extra_body={"mm_processor_kwargs": mm},
        )
        rec["success"] = True
        rec["usage"] = r.usage.model_dump()
        rec["content"] = r.choices[0].message.content[:500]
    except Exception as e:
        body = getattr(e, "body", None)
        rec["error"] = body["error"]["message"] if (body and "error" in body) else str(e)
    return rec


# ============================================================
# Test Matrix
# ============================================================
CASES = [
    # A. Basic
    ("A1", "[audio=T] text only",                              [user(TXT)],                    True),
    ("A2", "[audio=T] single image",                           [user(IMG1, TXT)],              True),
    ("A3", "[audio=T] single video (auto audio extraction)",   [user(VID1, TXT)],              True),
    ("A4", "[audio=T] explicit audio",                         [user(AUD, TXT)],               True),
    # B. Single video + image ordering
    ("B1", "[audio=T] video+image (video first)",              [user(VID1, IMG1, TXT)],        True),
    ("B2", "[audio=T] image+video (image first)",              [user(IMG1, VID1, TXT)],        True),
    ("B3", "[audio=T] video+text+image (text in middle)",      [user(VID1, TXT, IMG1)],        True),
    ("B4", "[audio=T] image+text+video (text in middle)",      [user(IMG1, TXT, VID1)],        True),
    ("B5", "[audio=T] video+image+text",                       [user(VID1, IMG1, TXT)],        True),
    ("B6", "[audio=T] image+video+text (image first)",         [user(IMG1, VID1, TXT)],        True),
    # C. Multi-video
    ("C1", "[audio=T] two videos",                             [user(VID1, VID2, TXT)],        True),
    ("C2", "[audio=T] two videos with text in middle",         [user(VID1, TXT, VID2)],        True),
    ("C3", "[audio=T] two videos with image in middle",        [user(VID1, IMG1, VID2, TXT)],  True),
    ("C4", "[audio=T] image + two videos",                     [user(IMG1, VID1, VID2, TXT)],  True),
    ("C5", "[audio=T] two videos + image",                     [user(VID1, VID2, IMG1, TXT)],  True),
    # D. Explicit audio mix
    ("D1", "[audio=T] video + explicit audio (audio first)",   [user(VID1, AUD, TXT)],         True),
    ("D2", "[audio=T] explicit audio + video (audio first)",   [user(AUD, VID1, TXT)],         True),
    ("D3", "[audio=T] image + video + explicit audio",         [user(IMG1, VID1, AUD, TXT)],   True),
    ("D4", "[audio=T] video + image + explicit audio",         [user(VID1, IMG1, AUD, TXT)],   True),
    # E. Control group
    ("E1", "[audio=F] single video",             [user(VID1, TXT)],        False),
    ("E2", "[audio=F] video + image",            [user(VID1, IMG1, TXT)],  False),
    ("E3", "[audio=F] image + video",            [user(IMG1, VID1, TXT)],  False),
    ("E4", "[audio=F] two videos",               [user(VID1, VID2, TXT)], False),
    ("E5", "[audio=F] video + explicit audio",   [user(VID1, AUD, TXT)],   False),
    # F. tool_calls returning image
    (
        "F1",
        "[audio=T] tool returns text only",
        [
            user(VID1, TXT),
            assistant(TOOL_SEARCH),
            tool("call_1", "video_keyframe_search", "Search result: no matching frame found"),
        ],
        True,
    ),
    (
        "F2",
        "[audio=T] tool returns image",
        [
            user(VID1, TXT),
            assistant(TOOL_SEARCH),
            tool("call_1", "video_keyframe_search", [TXT, IMG1, TXT]),
        ],
        True,
    ),
]


# ============================================================
# Run
# ============================================================
os.makedirs(os.path.dirname(RESULTS), exist_ok=True)

done_ids = set()
if os.path.exists(RESULTS):
    with open(RESULTS) as f:
        for line in f:
            done_ids.add(json.loads(line)["case_id"])

for case_id, desc, messages, use_audio in CASES:
    if case_id in done_ids:
        print(f"[{case_id}] {desc}  (skipped)")
        continue

    print(f"[{case_id}] {desc} ...", end=" ", flush=True)
    rec = request(case_id, desc, messages, use_audio)

    ok = alive()
    rec["alive"] = ok

    with open(RESULTS, "a") as f:
        f.write(json.dumps(rec, ensure_ascii=False) + "\n")

    if rec["success"]:
        print(f"  prompt_tokens={rec['usage']['prompt_tokens']}")
    else:
        print(f"  {rec['error']}")

    if not ok:
        print("  [STOP] server crashed, aborting remaining tests")
        break

    time.sleep(1)

print(f"\nDetailed results: {RESULTS}")

---

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @wendadawen.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[wendadawen]

@sighingnow @vadiklyutiy @DarkLight1337 @ywang96 @AndreasKaratzas @njhill Would anyone be able to review this PR to resolve the bug?

[AndreasKaratzas]

Can you keep the PR description and purpose simple and short and just open a new issue for the issue? Also can your PR just be in English (I am not an imperialist, but it makes it more parse-able in my head)?

[wendadawen]

@AndreasKaratzas I’ve simplified the PR description, changed all non-English parts in the test code to English, and split one old commit into three for easier reviewing. Thanks so much for your help!

[gty111]

@wendadawen Thanks for the fix! Could you rebase this branch onto the latest main (or merge main in)? It's currently based on fairly old main, which makes it hard to test against a recent build.

[wendadawen]

@gty111 rebase completed

[gty111]

Thanks for the fix! I verified it on the latest rebase and can confirm all three issues are resolved — the mixed image/video crash with use_audio_in_video=True is gone, and the mixed-modality outputs now look correct.

@wendadawen One small thing: the pre-commit check is currently failing — could you take a look? Thanks!
CC @ywang96