Automated PR - 2026-01-29

This commit is contained in:
sync-bot
2026-01-29 18:42:17 +00:00
parent 727c43e998
commit ca1623ad2a
31 changed files with 1723 additions and 663 deletions
+81 -6
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@@ -89,7 +89,7 @@ Do you need to condition on existing images/videos?
### Features Comparison
| Pipeline | Stages | CFG | Upsampling | Conditioning | Best For |
| Pipeline | Stages | [Multimodal Guidance](#%EF%B8%8F-multimodal-guidance) | Upsampling | Conditioning | Best For |
| -------- | ------ | --- | ---------- | ------------- | -------- |
| **TI2VidTwoStagesPipeline** | 2 | ✅ | ✅ | Image | **Production quality** (recommended) |
| **TI2VidOneStagePipeline** | 1 | ✅ | ❌ | Image | Educational, prototyping |
@@ -107,7 +107,7 @@ Do you need to condition on existing images/videos?
**Source**: [`src/ltx_pipelines/ti2vid_two_stages.py`](src/ltx_pipelines/ti2vid_two_stages.py)
Two-stage generation: Stage 1 generates low-resolution video with CFG guidance, Stage 2 upsamples to 2x resolution with distilled LoRA refinement. Supports image conditioning. Highest quality output, slower than one-stage but significantly better quality.
Two-stage generation: Stage 1 generates low-resolution video with [multimodal guidance](#%EF%B8%8F-multimodal-guidance), Stage 2 upsamples to 2x resolution with distilled LoRA refinement. Supports image conditioning. Highest quality output, slower than one-stage but significantly better quality.
**Use when:** Production-quality video generation, higher resolution needed, quality over speed, text-to-video with image conditioning.
@@ -121,7 +121,7 @@ Two-stage generation: Stage 1 generates low-resolution video with CFG guidance,
> **⚠️ Important:** This pipeline is primarily for educational purposes. For production-quality results, use `TI2VidTwoStagesPipeline` or other two-stage pipelines.
Single-stage generation (no upsampling) with CFG guidance and image conditioning support. Faster inference but lower resolution output (typically 512x768).
Single-stage generation (no upsampling) with [multimodal guidance](#%EF%B8%8F-multimodal-guidance) and image conditioning support. Faster inference but lower resolution output (typically 512x768).
**Use when:** Learning how the pipeline works, quick prototyping, testing, or when high resolution is not needed.
@@ -133,7 +133,7 @@ Single-stage generation (no upsampling) with CFG guidance and image conditioning
**Source**: [`src/ltx_pipelines/distilled.py`](src/ltx_pipelines/distilled.py)
Two-stage generation with 8 predefined sigmas (8 steps in stage 1, 4 steps in stage 2). No CFG guidance required. Fastest inference among all pipelines. Supports image conditioning. Requires spatial upsampler.
Two-stage generation with 8 predefined sigmas (8 steps in stage 1, 4 steps in stage 2). No guidance required. Fastest inference among all pipelines. Supports image conditioning. Requires spatial upsampler.
**Use when:** Fastest inference is critical, batch processing many videos, or when you have a distilled model checkpoint.
@@ -157,7 +157,7 @@ Two-stage generation with IC-LoRA support. Can condition on reference videos (vi
**Source**: [`src/ltx_pipelines/keyframe_interpolation.py`](src/ltx_pipelines/keyframe_interpolation.py)
Two-stage generation with keyframe interpolation. Uses guiding latents (additive conditioning) instead of replacing latents for smoother transitions. CFG guidance in stage 1, upsampling in stage 2.
Two-stage generation with keyframe interpolation. Uses guiding latents (additive conditioning) instead of replacing latents for smoother transitions. [Multimodal guidance](#%EF%B8%8F-multimodal-guidance) in stage 1, upsampling in stage 2.
**Use when:** You have keyframe images and want to interpolate between them, creating smooth transitions, or animation/motion interpolation tasks.
@@ -190,6 +190,61 @@ All pipelines support image conditioning, but with different methods:
---
## 🎛️ Multimodal Guidance
LTX-2 pipelines use **multimodal guidance** to steer the diffusion process for both video and audio modalities. Each modality (video, audio) has its own guider with independent parameters, allowing fine-grained control over generation quality and adherence to prompts.
### Guidance Parameters
The `MultiModalGuiderParams` dataclass controls guidance behavior:
| Parameter | Description |
| --------- | ----------- |
| `cfg_scale` | **Classifier-Free Guidance** scale. Higher values make the output adhere more strongly to the text prompt. Typical values: 2.05.0. Set to **1.0** to disable. |
| `stg_scale` | **Spatio-Temporal Guidance** scale. Controls perturbation-based guidance for improved temporal coherence. Typical values: 0.51.5. Set to **0.0** to disable. |
| `stg_blocks` | Which transformer blocks to perturb for STG (e.g., `[29]` for the last block). Set to **`[]`** to disable STG. |
| `rescale_scale` | Rescales the guided prediction to match the variance of the conditional prediction. Helps prevent over-saturation. Typical values: 0.50.7. Set to **0.0** to disable. |
| `modality_scale` | **Modality CFG** scale. Steers the model away from unsynced video and audio results, improving audio-visual coherence. Set to **1.0** to disable. |
| `skip_step` | Skip guidance every N steps. Can speed up inference with minimal quality loss. Set to **0** to disable (never skip). |
### How It Works
The multimodal guider combines three guidance signals during each denoising step:
1. **CFG (Text Guidance)**: Steers generation toward the text prompt by computing `(cond - uncond_text)`.
2. **STG (Perturbation Guidance)**: Improves structural coherence by perturbing specific transformer blocks and steering away from the perturbed prediction.
3. **Modality CFG**: For joint audio-video generation, steers the model away from unsynced video and audio results.
### Example Configuration
```python
from ltx_core.components.guiders import MultiModalGuiderParams
# Video guider: moderate CFG, STG enabled, modality isolation
video_guider_params = MultiModalGuiderParams(
cfg_scale=3.0,
stg_scale=1.0,
rescale_scale=0.7,
modality_scale=3.0,
stg_blocks=[29],
)
# Audio guider: higher CFG for stronger prompt adherence
audio_guider_params = MultiModalGuiderParams(
cfg_scale=7.0,
stg_scale=1.0,
rescale_scale=0.7,
modality_scale=3.0,
stg_blocks=[29],
)
```
> **Tip:** Start with the default values from [`constants.py`](src/ltx_pipelines/utils/constants.py) and adjust based on your use case. Higher `cfg_scale` = stronger prompt adherence but potentially less natural motion; higher `stg_scale` = better temporal coherence but slower inference (requires extra forward passes).
>
> **Tip:** When generating video with audio, set `modality_scale` > 1.0 (e.g., 3.0) to improve audio-visual sync. If generating video-only, set it to 1.0 to disable.
---
## ⚡ Optimization Tips
@@ -276,6 +331,7 @@ This allows you to use **20-30 steps instead of 40** while maintaining quality.
```python
from ltx_core.loader import LTXV_LORA_COMFY_RENAMING_MAP, LoraPathStrengthAndSDOps
from ltx_pipelines.ti2vid_two_stages import TI2VidTwoStagesPipeline
from ltx_core.components.guiders import MultiModalGuiderParams
distilled_lora = [
LoraPathStrengthAndSDOps(
@@ -293,6 +349,24 @@ pipeline = TI2VidTwoStagesPipeline(
loras=[],
)
video_guider_params = MultiModalGuiderParams(
cfg_scale=3.0,
stg_scale=1.0,
rescale_scale=0.7,
modality_scale=3.0,
skip_step=0,
stg_blocks=[29],
)
audio_guider_params = MultiModalGuiderParams(
cfg_scale=7.0,
stg_scale=1.0,
rescale_scale=0.7,
modality_scale=3.0,
skip_step=0,
stg_blocks=[29],
)
# Generate video from image
pipeline(
prompt="A serene landscape with mountains in the background",
@@ -303,7 +377,8 @@ pipeline(
num_frames=121,
frame_rate=25.0,
num_inference_steps=40,
cfg_guidance_scale=3.0,
video_guider_params=video_guider_params,
audio_guider_params=audio_guider_params,
images=[("input_image.jpg", 0, 1.0)], # Image at frame 0, strength 1.0
)
```
@@ -2,11 +2,12 @@ import logging
from collections.abc import Iterator
import torch
from safetensors import safe_open
from ltx_core.components.diffusion_steps import EulerDiffusionStep
from ltx_core.components.noisers import GaussianNoiser
from ltx_core.components.protocols import DiffusionStepProtocol
from ltx_core.conditioning import ConditioningItem, VideoConditionByKeyframeIndex
from ltx_core.conditioning import ConditioningItem, VideoConditionByReferenceLatent
from ltx_core.loader import LoraPathStrengthAndSDOps
from ltx_core.model.audio_vae import decode_audio as vae_decode_audio
from ltx_core.model.upsampler import upsample_video
@@ -81,6 +82,21 @@ class ICLoraPipeline:
)
self.device = device
# Read reference downscale factor from LoRA metadata.
# IC-LoRAs trained with low-resolution reference videos store this factor
# so inference can resize reference videos to match training conditions.
self.reference_downscale_factor = 1
for lora in loras:
scale = _read_lora_reference_downscale_factor(lora.path)
if scale != 1:
if self.reference_downscale_factor not in (1, scale):
raise ValueError(
f"Conflicting reference_downscale_factor values in LoRAs: "
f"already have {self.reference_downscale_factor}, but {lora.path} "
f"specifies {scale}. Cannot combine LoRAs with different reference scales."
)
self.reference_downscale_factor = scale
@torch.inference_mode()
def __call__(
self,
@@ -249,17 +265,34 @@ class ICLoraPipeline:
device=self.device,
)
# Calculate scaled dimensions for reference video conditioning.
# IC-LoRAs trained with downscaled reference videos expect the same ratio at inference.
scale = self.reference_downscale_factor
if scale != 1 and (height % scale != 0 or width % scale != 0):
raise ValueError(
f"Output dimensions ({height}x{width}) must be divisible by reference_downscale_factor ({scale})"
)
ref_height = height // scale
ref_width = width // scale
for video_path, strength in video_conditioning:
# Load video at scaled-down resolution (if scale > 1)
video = load_video_conditioning(
video_path=video_path,
height=height,
width=width,
height=ref_height,
width=ref_width,
frame_cap=num_frames,
dtype=self.dtype,
device=self.device,
)
encoded_video = video_encoder(video)
conditionings.append(VideoConditionByKeyframeIndex(keyframes=encoded_video, frame_idx=0, strength=strength))
conditionings.append(
VideoConditionByReferenceLatent(
latent=encoded_video,
downscale_factor=scale,
strength=strength,
)
)
return conditionings
@@ -307,5 +340,26 @@ def main() -> None:
)
def _read_lora_reference_downscale_factor(lora_path: str) -> int:
"""Read reference_downscale_factor from LoRA safetensors metadata.
Some IC-LoRA models are trained with reference videos at lower resolution than
the target output. This allows for more efficient training and can improve
generalization. The downscale factor indicates the ratio between target and
reference resolutions (e.g., factor=2 means reference is half the resolution).
Args:
lora_path: Path to the LoRA .safetensors file
Returns:
The reference downscale factor (1 if not specified in metadata, meaning
reference and target have the same resolution)
"""
try:
with safe_open(lora_path, framework="pt") as f:
metadata = f.metadata() or {}
return int(metadata.get("reference_downscale_factor", 1))
except Exception as e:
logging.warning(f"Failed to read metadata from LoRA file '{lora_path}': {e}")
return 1
if __name__ == "__main__":
main()
@@ -4,7 +4,7 @@ from collections.abc import Iterator
import torch
from ltx_core.components.diffusion_steps import EulerDiffusionStep
from ltx_core.components.guiders import CFGGuider
from ltx_core.components.guiders import MultiModalGuider, MultiModalGuiderParams
from ltx_core.components.noisers import GaussianNoiser
from ltx_core.components.protocols import DiffusionStepProtocol
from ltx_core.components.schedulers import LTX2Scheduler
@@ -28,8 +28,8 @@ from ltx_pipelines.utils.helpers import (
euler_denoising_loop,
generate_enhanced_prompt,
get_device,
guider_denoising_func,
image_conditionings_by_adding_guiding_latent,
multi_modal_guider_denoising_func,
simple_denoising_func,
)
from ltx_pipelines.utils.media_io import encode_video
@@ -86,7 +86,8 @@ class KeyframeInterpolationPipeline:
num_frames: int,
frame_rate: float,
num_inference_steps: int,
cfg_guidance_scale: float,
video_guider_params: MultiModalGuiderParams,
audio_guider_params: MultiModalGuiderParams,
images: list[tuple[str, int, float]],
tiling_config: TilingConfig | None = None,
enhance_prompt: bool = False,
@@ -96,7 +97,6 @@ class KeyframeInterpolationPipeline:
generator = torch.Generator(device=self.device).manual_seed(seed)
noiser = GaussianNoiser(generator=generator)
stepper = EulerDiffusionStep()
cfg_guider = CFGGuider(cfg_guidance_scale)
dtype = torch.bfloat16
text_encoder = self.stage_1_model_ledger.text_encoder()
@@ -125,12 +125,17 @@ class KeyframeInterpolationPipeline:
video_state=video_state,
audio_state=audio_state,
stepper=stepper,
denoise_fn=guider_denoising_func(
cfg_guider,
v_context_p,
v_context_n,
a_context_p,
a_context_n,
denoise_fn=multi_modal_guider_denoising_func(
video_guider=MultiModalGuider(
params=video_guider_params,
negative_context=v_context_n,
),
audio_guider=MultiModalGuider(
params=audio_guider_params,
negative_context=a_context_n,
),
v_context=v_context_p,
a_context=a_context_p,
transformer=transformer, # noqa: F821
),
)
@@ -256,7 +261,22 @@ def main() -> None:
num_frames=args.num_frames,
frame_rate=args.frame_rate,
num_inference_steps=args.num_inference_steps,
cfg_guidance_scale=args.cfg_guidance_scale,
video_guider_params=MultiModalGuiderParams(
cfg_scale=args.video_cfg_guidance_scale,
stg_scale=args.video_stg_guidance_scale,
rescale_scale=args.video_rescale_scale,
modality_scale=args.a2v_guidance_scale,
skip_step=args.video_skip_step,
stg_blocks=args.video_stg_blocks,
),
audio_guider_params=MultiModalGuiderParams(
cfg_scale=args.audio_cfg_guidance_scale,
stg_scale=args.audio_stg_guidance_scale,
rescale_scale=args.audio_rescale_scale,
modality_scale=args.v2a_guidance_scale,
skip_step=args.audio_skip_step,
stg_blocks=args.audio_stg_blocks,
),
images=args.images,
tiling_config=tiling_config,
)
@@ -4,7 +4,7 @@ from collections.abc import Iterator
import torch
from ltx_core.components.diffusion_steps import EulerDiffusionStep
from ltx_core.components.guiders import CFGGuider
from ltx_core.components.guiders import MultiModalGuider, MultiModalGuiderParams
from ltx_core.components.noisers import GaussianNoiser
from ltx_core.components.protocols import DiffusionStepProtocol
from ltx_core.components.schedulers import LTX2Scheduler
@@ -23,8 +23,8 @@ from ltx_pipelines.utils.helpers import (
euler_denoising_loop,
generate_enhanced_prompt,
get_device,
guider_denoising_func,
image_conditionings_by_replacing_latent,
multi_modal_guider_denoising_func,
)
from ltx_pipelines.utils.media_io import encode_video
from ltx_pipelines.utils.types import PipelineComponents
@@ -73,7 +73,8 @@ class TI2VidOneStagePipeline:
num_frames: int,
frame_rate: float,
num_inference_steps: int,
cfg_guidance_scale: float,
video_guider_params: MultiModalGuiderParams,
audio_guider_params: MultiModalGuiderParams,
images: list[tuple[str, int, float]],
enhance_prompt: bool = False,
) -> tuple[Iterator[torch.Tensor], torch.Tensor]:
@@ -82,7 +83,6 @@ class TI2VidOneStagePipeline:
generator = torch.Generator(device=self.device).manual_seed(seed)
noiser = GaussianNoiser(generator=generator)
stepper = EulerDiffusionStep()
cfg_guider = CFGGuider(cfg_guidance_scale)
dtype = torch.bfloat16
text_encoder = self.model_ledger.text_encoder()
@@ -111,12 +111,17 @@ class TI2VidOneStagePipeline:
video_state=video_state,
audio_state=audio_state,
stepper=stepper,
denoise_fn=guider_denoising_func(
cfg_guider,
v_context_p,
v_context_n,
a_context_p,
a_context_n,
denoise_fn=multi_modal_guider_denoising_func(
video_guider=MultiModalGuider(
params=video_guider_params,
negative_context=v_context_n,
),
audio_guider=MultiModalGuider(
params=audio_guider_params,
negative_context=a_context_n,
),
v_context=v_context_p,
a_context=a_context_p,
transformer=transformer, # noqa: F821
),
)
@@ -175,7 +180,22 @@ def main() -> None:
num_frames=args.num_frames,
frame_rate=args.frame_rate,
num_inference_steps=args.num_inference_steps,
cfg_guidance_scale=args.cfg_guidance_scale,
video_guider_params=MultiModalGuiderParams(
cfg_scale=args.video_cfg_guidance_scale,
stg_scale=args.video_stg_guidance_scale,
rescale_scale=args.video_rescale_scale,
modality_scale=args.a2v_guidance_scale,
skip_step=args.video_skip_step,
stg_blocks=args.video_stg_blocks,
),
audio_guider_params=MultiModalGuiderParams(
cfg_scale=args.audio_cfg_guidance_scale,
stg_scale=args.audio_stg_guidance_scale,
rescale_scale=args.audio_rescale_scale,
modality_scale=args.v2a_guidance_scale,
skip_step=args.audio_skip_step,
stg_blocks=args.audio_stg_blocks,
),
images=args.images,
)
@@ -4,7 +4,7 @@ from collections.abc import Iterator
import torch
from ltx_core.components.diffusion_steps import EulerDiffusionStep
from ltx_core.components.guiders import CFGGuider
from ltx_core.components.guiders import MultiModalGuider, MultiModalGuiderParams
from ltx_core.components.noisers import GaussianNoiser
from ltx_core.components.protocols import DiffusionStepProtocol
from ltx_core.components.schedulers import LTX2Scheduler
@@ -28,8 +28,8 @@ from ltx_pipelines.utils.helpers import (
euler_denoising_loop,
generate_enhanced_prompt,
get_device,
guider_denoising_func,
image_conditionings_by_replacing_latent,
multi_modal_guider_denoising_func,
simple_denoising_func,
)
from ltx_pipelines.utils.media_io import encode_video
@@ -88,7 +88,8 @@ class TI2VidTwoStagesPipeline:
num_frames: int,
frame_rate: float,
num_inference_steps: int,
cfg_guidance_scale: float,
video_guider_params: MultiModalGuiderParams,
audio_guider_params: MultiModalGuiderParams,
images: list[tuple[str, int, float]],
tiling_config: TilingConfig | None = None,
enhance_prompt: bool = False,
@@ -98,7 +99,6 @@ class TI2VidTwoStagesPipeline:
generator = torch.Generator(device=self.device).manual_seed(seed)
noiser = GaussianNoiser(generator=generator)
stepper = EulerDiffusionStep()
cfg_guider = CFGGuider(cfg_guidance_scale)
dtype = torch.bfloat16
text_encoder = self.stage_1_model_ledger.text_encoder()
@@ -127,12 +127,17 @@ class TI2VidTwoStagesPipeline:
video_state=video_state,
audio_state=audio_state,
stepper=stepper,
denoise_fn=guider_denoising_func(
cfg_guider,
v_context_p,
v_context_n,
a_context_p,
a_context_n,
denoise_fn=multi_modal_guider_denoising_func(
video_guider=MultiModalGuider(
params=video_guider_params,
negative_context=v_context_n,
),
audio_guider=MultiModalGuider(
params=audio_guider_params,
negative_context=a_context_n,
),
v_context=v_context_p,
a_context=a_context_p,
transformer=transformer, # noqa: F821
),
)
@@ -259,7 +264,22 @@ def main() -> None:
num_frames=args.num_frames,
frame_rate=args.frame_rate,
num_inference_steps=args.num_inference_steps,
cfg_guidance_scale=args.cfg_guidance_scale,
video_guider_params=MultiModalGuiderParams(
cfg_scale=args.video_cfg_guidance_scale,
stg_scale=args.video_stg_guidance_scale,
rescale_scale=args.video_rescale_scale,
modality_scale=args.a2v_guidance_scale,
skip_step=args.video_skip_step,
stg_blocks=args.video_stg_blocks,
),
audio_guider_params=MultiModalGuiderParams(
cfg_scale=args.audio_cfg_guidance_scale,
stg_scale=args.audio_stg_guidance_scale,
rescale_scale=args.audio_rescale_scale,
modality_scale=args.v2a_guidance_scale,
skip_step=args.audio_skip_step,
stg_blocks=args.audio_stg_blocks,
),
images=args.images,
tiling_config=tiling_config,
)
@@ -7,13 +7,14 @@ from ltx_pipelines.utils.constants import (
DEFAULT_1_STAGE_WIDTH,
DEFAULT_2_STAGE_HEIGHT,
DEFAULT_2_STAGE_WIDTH,
DEFAULT_CFG_GUIDANCE_SCALE,
DEFAULT_AUDIO_GUIDER_PARAMS,
DEFAULT_FRAME_RATE,
DEFAULT_LORA_STRENGTH,
DEFAULT_NEGATIVE_PROMPT,
DEFAULT_NUM_FRAMES,
DEFAULT_NUM_INFERENCE_STEPS,
DEFAULT_SEED,
DEFAULT_VIDEO_GUIDER_PARAMS,
)
@@ -185,16 +186,6 @@ def basic_arg_parser() -> argparse.ArgumentParser:
def default_1_stage_arg_parser() -> argparse.ArgumentParser:
parser = basic_arg_parser()
parser.add_argument(
"--cfg-guidance-scale",
type=float,
default=DEFAULT_CFG_GUIDANCE_SCALE,
help=(
f"Classifier-free guidance (CFG) scale controlling how strongly "
f"the model adheres to the prompt. Higher values increase prompt "
f"adherence but may reduce diversity (default: {DEFAULT_CFG_GUIDANCE_SCALE})."
),
)
parser.add_argument(
"--negative-prompt",
type=str,
@@ -205,7 +196,126 @@ def default_1_stage_arg_parser() -> argparse.ArgumentParser:
"Default: a comprehensive negative prompt covering common artifacts and quality issues."
),
)
parser.add_argument(
"--video-cfg-guidance-scale",
type=float,
default=DEFAULT_VIDEO_GUIDER_PARAMS.cfg_scale,
help=(
f"Classifier-free guidance (CFG) scale controlling how strongly "
f"the model adheres to the video prompt. Higher values increase prompt "
"adherence but may reduce diversity. 1.0 means no effect "
f"(default: {DEFAULT_VIDEO_GUIDER_PARAMS.cfg_scale})."
),
)
parser.add_argument(
"--video-stg-guidance-scale",
type=float,
default=DEFAULT_VIDEO_GUIDER_PARAMS.stg_scale,
help=(
f"STG (Spatio-Temporal Guidance) scale controlling how strongly "
f"the model reacts to the perturbation of the video modality. Higher values increase "
f"the effect but may reduce quality. 0.0 means no effect "
f"(default: {DEFAULT_VIDEO_GUIDER_PARAMS.stg_scale})."
),
)
parser.add_argument(
"--video-rescale-scale",
type=float,
default=DEFAULT_VIDEO_GUIDER_PARAMS.rescale_scale,
help=(
f"Rescale scale controlling how strongly "
f"the model rescales the video modality after applying other guidance. Higher values tend to decrease "
f"oversaturation effects. 0.0 means no effect (default: {DEFAULT_VIDEO_GUIDER_PARAMS.rescale_scale})."
),
)
parser.add_argument(
"--video-stg-blocks",
type=int,
nargs="*",
default=DEFAULT_VIDEO_GUIDER_PARAMS.stg_blocks,
help=(f"Which transformer blocks to perturb for STG. Default: {DEFAULT_VIDEO_GUIDER_PARAMS.stg_blocks}."),
)
parser.add_argument(
"--a2v-guidance-scale",
type=float,
default=DEFAULT_VIDEO_GUIDER_PARAMS.modality_scale,
help=(
f"A2V (Audio-to-Video) guidance scale controlling how strongly "
f"the model reacts to the perturbation of the audio-to-video cross-attention. Higher values may increase "
f"lipsync quality. 1.0 means no effect (default: {DEFAULT_VIDEO_GUIDER_PARAMS.modality_scale})."
),
)
parser.add_argument(
"--video-skip-step",
type=int,
default=DEFAULT_VIDEO_GUIDER_PARAMS.skip_step,
help=(
"Video skip step N controls periodic skipping during the video diffusion process: "
"only steps where step_index % (N + 1) == 0 are processed, all others are skipped "
f"(e.g., 0 = no skipping; 1 = skip every other step; 2 = skip 2 of every 3 steps; "
f"default: {DEFAULT_VIDEO_GUIDER_PARAMS.skip_step})."
),
)
parser.add_argument(
"--audio-cfg-guidance-scale",
type=float,
default=DEFAULT_AUDIO_GUIDER_PARAMS.cfg_scale,
help=(
f"Audio CFG (Classifier-free guidance) scale controlling how strongly "
f"the model adheres to the audio prompt. Higher values increase prompt "
f"adherence but may reduce diversity. 1.0 means no effect "
f"(default: {DEFAULT_AUDIO_GUIDER_PARAMS.cfg_scale})."
),
)
parser.add_argument(
"--audio-stg-guidance-scale",
type=float,
default=DEFAULT_AUDIO_GUIDER_PARAMS.stg_scale,
help=(
f"Audio STG (Spatio-Temporal Guidance) scale controlling how strongly "
f"the model reacts to the perturbation of the audio modality. Higher values increase "
f"the effect but may reduce quality. 0.0 means no effect "
f"(default: {DEFAULT_AUDIO_GUIDER_PARAMS.stg_scale})."
),
)
parser.add_argument(
"--audio-rescale-scale",
type=float,
default=DEFAULT_AUDIO_GUIDER_PARAMS.rescale_scale,
help=(
f"Audio rescale scale controlling how strongly "
f"the model rescales the audio modality after applying other guidance. "
f"Experimental. 0.0 means no effect (default: {DEFAULT_AUDIO_GUIDER_PARAMS.rescale_scale})."
),
)
parser.add_argument(
"--audio-stg-blocks",
type=int,
nargs="*",
default=DEFAULT_AUDIO_GUIDER_PARAMS.stg_blocks,
help=(f"Which transformer blocks to perturb for Audio STG. Default: {DEFAULT_AUDIO_GUIDER_PARAMS.stg_blocks}."),
)
parser.add_argument(
"--v2a-guidance-scale",
type=float,
default=DEFAULT_AUDIO_GUIDER_PARAMS.modality_scale,
help=(
f"V2A (Video-to-Audio) guidance scale controlling how strongly "
f"the model reacts to the perturbation of the video-to-audio cross-attention. Higher values may increase "
f"lipsync quality. 1.0 means no effect (default: {DEFAULT_AUDIO_GUIDER_PARAMS.modality_scale})."
),
)
parser.add_argument(
"--audio-skip-step",
type=int,
default=DEFAULT_AUDIO_GUIDER_PARAMS.skip_step,
help=(
"Audio skip step N controls periodic skipping during the audio diffusion process: "
"only steps where step_index % (N + 1) == 0 are processed, all others are skipped "
f"(e.g., 0 = no skipping; 1 = skip every other step; 2 = skip 2 of every 3 steps; "
f"default: {DEFAULT_AUDIO_GUIDER_PARAMS.skip_step})."
),
)
return parser
@@ -4,6 +4,7 @@
# Noise schedule for the distilled pipeline. These sigma values control noise
# levels at each denoising step and were tuned to match the distillation process.
from ltx_core.components.guiders import MultiModalGuiderParams
from ltx_core.types import SpatioTemporalScaleFactors
DISTILLED_SIGMA_VALUES = [1.0, 0.99375, 0.9875, 0.98125, 0.975, 0.909375, 0.725, 0.421875, 0.0]
@@ -24,13 +25,28 @@ DEFAULT_2_STAGE_WIDTH = DEFAULT_1_STAGE_WIDTH * 2
DEFAULT_NUM_FRAMES = 121
DEFAULT_FRAME_RATE = 24.0
DEFAULT_NUM_INFERENCE_STEPS = 40
DEFAULT_CFG_GUIDANCE_SCALE = 4.0
DEFAULT_VIDEO_GUIDER_PARAMS = MultiModalGuiderParams(
cfg_scale=3.0,
stg_scale=1.0,
rescale_scale=0.7,
modality_scale=3.0,
skip_step=0,
stg_blocks=[29],
)
# =============================================================================
# Audio
# =============================================================================
DEFAULT_AUDIO_GUIDER_PARAMS = MultiModalGuiderParams(
cfg_scale=7.0,
stg_scale=1.0,
rescale_scale=0.7,
modality_scale=3.0,
skip_step=0,
stg_blocks=[29],
)
AUDIO_SAMPLE_RATE = 24000
@@ -5,6 +5,7 @@ from dataclasses import replace
import torch
from tqdm import tqdm
from ltx_core.components.guiders import MultiModalGuider
from ltx_core.components.noisers import Noiser
from ltx_core.components.protocols import DiffusionStepProtocol, GuiderProtocol
from ltx_core.conditioning import (
@@ -12,6 +13,12 @@ from ltx_core.conditioning import (
VideoConditionByKeyframeIndex,
VideoConditionByLatentIndex,
)
from ltx_core.guidance.perturbations import (
BatchedPerturbationConfig,
Perturbation,
PerturbationConfig,
PerturbationType,
)
from ltx_core.model.transformer import Modality, X0Model
from ltx_core.model.video_vae import VideoEncoder
from ltx_core.text_encoders.gemma import GemmaTextEncoderModelBase
@@ -376,6 +383,113 @@ def guider_denoising_func(
return guider_denoising_step
def multi_modal_guider_denoising_func(
video_guider: MultiModalGuider,
audio_guider: MultiModalGuider,
v_context: torch.Tensor,
a_context: torch.Tensor,
transformer: X0Model,
) -> DenoisingFunc:
last_denoised_video = None
last_denoised_audio = None
def guider_denoising_step(
video_state: LatentState, audio_state: LatentState, sigmas: torch.Tensor, step_index: int
) -> tuple[torch.Tensor, torch.Tensor]:
nonlocal last_denoised_video, last_denoised_audio
if video_guider.should_skip_step(step_index) and audio_guider.should_skip_step(step_index):
return last_denoised_video, last_denoised_audio
sigma = sigmas[step_index]
pos_video_modality = modality_from_latent_state(
video_state, v_context, sigma, enabled=not video_guider.should_skip_step(step_index)
)
pos_audio_modality = modality_from_latent_state(
audio_state, a_context, sigma, enabled=not audio_guider.should_skip_step(step_index)
)
denoised_video, denoised_audio = transformer(
video=pos_video_modality, audio=pos_audio_modality, perturbations=None
)
neg_denoised_video, neg_denoised_audio = 0.0, 0.0
if video_guider.do_unconditional_generation() or audio_guider.do_unconditional_generation():
if video_guider.do_unconditional_generation() and video_guider.negative_context is None:
raise ValueError("Negative context is required for unconditioned denoising")
if audio_guider.do_unconditional_generation() and audio_guider.negative_context is None:
raise ValueError("Negative context is required for unconditioned denoising")
neg_video_modality = modality_from_latent_state(
video_state,
video_guider.negative_context
if video_guider.negative_context is not None
else pos_video_modality.context,
sigma,
)
neg_audio_modality = modality_from_latent_state(
audio_state,
audio_guider.negative_context
if audio_guider.negative_context is not None
else pos_audio_modality.context,
sigma,
)
neg_denoised_video, neg_denoised_audio = transformer(
video=neg_video_modality, audio=neg_audio_modality, perturbations=None
)
ptb_denoised_video, ptb_denoised_audio = 0.0, 0.0
if video_guider.do_perturbed_generation() or audio_guider.do_perturbed_generation():
perturbations = []
if video_guider.do_perturbed_generation():
perturbations.append(
Perturbation(type=PerturbationType.SKIP_VIDEO_SELF_ATTN, blocks=video_guider.params.stg_blocks)
)
if audio_guider.do_perturbed_generation():
perturbations.append(
Perturbation(type=PerturbationType.SKIP_AUDIO_SELF_ATTN, blocks=audio_guider.params.stg_blocks)
)
perturbation_config = PerturbationConfig(perturbations=perturbations)
ptb_denoised_video, ptb_denoised_audio = transformer(
video=pos_video_modality,
audio=pos_audio_modality,
perturbations=BatchedPerturbationConfig(perturbations=[perturbation_config]),
)
mod_denoised_video, mod_denoised_audio = 0.0, 0.0
if video_guider.do_isolated_modality_generation() or audio_guider.do_isolated_modality_generation():
perturbations = [
Perturbation(type=PerturbationType.SKIP_A2V_CROSS_ATTN, blocks=None),
Perturbation(type=PerturbationType.SKIP_V2A_CROSS_ATTN, blocks=None),
]
perturbation_config = PerturbationConfig(perturbations=perturbations)
mod_denoised_video, mod_denoised_audio = transformer(
video=pos_video_modality,
audio=pos_audio_modality,
perturbations=BatchedPerturbationConfig(perturbations=[perturbation_config]),
)
if video_guider.should_skip_step(step_index):
denoised_video = last_denoised_video
else:
denoised_video = video_guider.calculate(
denoised_video, neg_denoised_video, ptb_denoised_video, mod_denoised_video
)
if audio_guider.should_skip_step(step_index):
denoised_audio = last_denoised_audio
else:
denoised_audio = audio_guider.calculate(
denoised_audio, neg_denoised_audio, ptb_denoised_audio, mod_denoised_audio
)
last_denoised_video = denoised_video
last_denoised_audio = denoised_audio
return denoised_video, denoised_audio
return guider_denoising_step
def denoise_audio_video( # noqa: PLR0913
output_shape: VideoPixelShape,
conditionings: list[ConditioningItem],
@@ -35,6 +35,8 @@ from ltx_core.text_encoders.gemma import (
AVGemmaTextEncoderModelConfigurator,
module_ops_from_gemma_root,
)
from ltx_core.text_encoders.gemma.encoders.av_encoder import GEMMA_MODEL_OPS
from ltx_core.utils import find_matching_file
class ModelLedger:
@@ -143,12 +145,16 @@ class ModelLedger:
)
if self.gemma_root_path is not None:
module_ops = module_ops_from_gemma_root(self.gemma_root_path)
model_folder = find_matching_file(self.gemma_root_path, "model*.safetensors").parent
weight_paths = [str(p) for p in model_folder.rglob("*.safetensors")]
self.text_encoder_builder = Builder(
model_path=self.checkpoint_path,
model_path=(str(self.checkpoint_path), *weight_paths),
model_class_configurator=AVGemmaTextEncoderModelConfigurator,
model_sd_ops=AV_GEMMA_TEXT_ENCODER_KEY_OPS,
registry=self.registry,
module_ops=module_ops_from_gemma_root(self.gemma_root_path),
module_ops=(GEMMA_MODEL_OPS, *module_ops),
)
if self.spatial_upsampler_path is not None: