[Model][Frontend] MiniMax-H3: Add latent-mask editing (#7465)

Signed-off-by: xiaoyu <1259084489@qq.com>

docs/serving/videos_api.md

@@ -73,6 +73,10 @@ curl -L "http://localhost:8091/v1/videos/${video_id}/content" -o output.mp4
 | `image_reference` | string | null | JSON-encoded reference image payload; do not combine with `input_reference` or `video_reference` |
 | `video_reference` | string | null | JSON-encoded reference video payload; do not combine with `input_reference` or `image_reference` |
 | `audio_reference` | string | null | JSON-encoded audio reference for speech-to-video: `{"audio_url": "..."}` — supports HTTP(s) URLs or base64 data URLs |
+| `source_video` | file | null | MiniMax H3 latent-edit source video (`.mp4` or `.mov`, up to 512 MiB) |
+| `source_audio` | file | null | Optional MiniMax H3 latent-edit source audio (`.wav` or `.mp3`, up to 512 MiB) |
+| `video_noise_mask` | file | null | UTF-8 JSON MiniMax H3 video mask; `0` preserves and `1` regenerates a token |
+| `audio_noise_mask` | file | null | UTF-8 JSON MiniMax H3 audio mask; `0` preserves and `1` regenerates a token |
 | `width` | integer | model default | Output video width |
 | `height` | integer | model default | Output video height |
 | `num_frames` | integer | 1 | Number of generated frames |
@@ -214,6 +218,49 @@ upstream vLLM's media URL allowlist protection. Deployments should therefore
 treat remote media URLs as untrusted and choose this setting as part of their
 URL access policy.
 
+### MiniMax H3 Latent-Mask Editing
+
+MiniMax H3 accepts request-scoped source media and video/audio noise masks.
+At least one mask is required. A nontrivial `video_noise_mask` requires
+`source_video`, while a nontrivial `audio_noise_mask` requires either
+`source_audio` or a `source_video` with an audio stream. Mask values are in
+`[0, 1]`: `0` preserves the source, `1` regenerates it, and fractional values
+blend the two behaviors. Exact all-one masks are no-ops and do not require a
+source. Source uploads without a mask are rejected. Masks may be a JSON scalar
+or arrays matching the H3 latent/token grid; pixel-resolution masks must be
+resized or pooled by the client before upload.
+
+For an aligned output of `F` frames at `W x H`, the video latent grid is
+`[Tv, H/16, W/16]`, where `Tv = 2 + 5 * ((F - 5) / 17)`. The video mask may be
+a scalar, a flat token vector, `[Tv, H/32, W/32]`, or the full latent grid. For
+the model input, timestep, and velocity, a full-grid mask is max-pooled over
+each 2x2 spatial token and fractional values are rounded upward to 1/256
+levels. The final x0 restore uses the original, unquantized mask, so full-grid
+masks retain cell-level preservation inside a model token. The audio length is
+`Ta = round(F * 40 / 24)`, and its mask may be a scalar, `[Ta]`, `[2, Ta]`, or
+a flat `2 * Ta` vector. If source audio is short, its missing latent tail is
+forced to mask value `1` so H3 generates that portion. Each mask must be sent
+as a UTF-8 JSON file part and is limited to 8 MiB. A file may contain either a
+JSON scalar or an array.
+
+```bash
+curl -s http://localhost:8091/v1/videos/sync \
+  -F "prompt=Partially restyle the complete clip and soundtrack" \
+  -F 'extra_params={"task":"t2va","duration":4.0,"aspect_ratio":"16:9"}' \
+  -F "source_video=@source.mp4;type=video/mp4" \
+  -F "source_audio=@source.wav;type=audio/wav" \
+  -F "video_noise_mask=@video-mask.json;type=application/json" \
+  -F "audio_noise_mask=@audio-mask.json;type=application/json" \
+  -o edited.mp4
+```
+
+For example, each mask file in the request above may contain the JSON scalar
+`0.5`.
+
+The server streams source files to temporary request-scoped storage and removes
+them after synchronous or asynchronous generation finishes. Models that do not
+declare latent-mask editing support reject these fields.
+
 ### Speech-to-Video
 
 For models that support audio-driven generation (e.g., Wan2.2-S2V), pass both