Files
ltx2-mps/generate.py
Norbert Schmidt fc95099449 Added audio
2026-01-11 15:37:27 +01:00

110 lines
3.5 KiB
Python

#!/usr/bin/env python3
"""
ltx-2 video generator for mps
usage: python generate.py "your prompt" -o output.mp4
"""
import argparse
import sys
import numpy as np
import torch
from diffusers import LTX2Pipeline
from diffusers.pipelines.ltx2.export_utils import encode_video
def main():
parser = argparse.ArgumentParser(description="ltx-2 video generator for mps")
parser.add_argument("prompt", help="text prompt")
parser.add_argument("-o", "--output", default="output.mp4", help="output path")
parser.add_argument("-n", "--negative-prompt", default="", help="negative prompt")
parser.add_argument("--steps", type=int, default=20, help="inference steps")
parser.add_argument("--guidance", type=float, default=5.0, help="guidance scale")
parser.add_argument("--width", type=int, default=512, help="video width")
parser.add_argument("--height", type=int, default=320, help="video height")
parser.add_argument("--frames", type=int, default=25, help="frame count")
parser.add_argument("--fps", type=int, default=24, help="output fps")
parser.add_argument("--seed", type=int, default=None, help="random seed")
parser.add_argument("--no-audio", action="store_true", help="disable audio generation")
args = parser.parse_args()
if args.width % 32 != 0:
print(f"error: width must be divisible by 32 (got {args.width})")
sys.exit(1)
if args.height % 32 != 0:
print(f"error: height must be divisible by 32 (got {args.height})")
sys.exit(1)
if (args.frames - 1) % 8 != 0:
valid = [8*i + 1 for i in range(1, 13)]
print(f"error: frames must be 8n+1 (valid: {valid})")
sys.exit(1)
if not torch.backends.mps.is_available():
print("warning: mps not available, using cpu (slow)")
device = "cpu"
else:
device = "mps"
print("using mps")
print("loading model...")
pipe = LTX2Pipeline.from_pretrained(
"Lightricks/LTX-2",
torch_dtype=torch.bfloat16
)
pipe.to(device)
print("model loaded")
if args.seed is None:
args.seed = torch.randint(0, 2**31, (1,)).item()
generator = torch.Generator(device="cpu")
generator.manual_seed(args.seed)
print(f"\ngenerating{'...' if args.no_audio else ' with audio...'}")
print(f" prompt: {args.prompt}")
print(f" size: {args.width}x{args.height}, {args.frames} frames")
print(f" steps: {args.steps}, guidance: {args.guidance}")
print(f" seed: {args.seed}")
print()
result = pipe(
prompt=args.prompt,
negative_prompt=args.negative_prompt if args.negative_prompt else None,
num_inference_steps=args.steps,
guidance_scale=args.guidance,
width=args.width,
height=args.height,
num_frames=args.frames,
generator=generator,
)
# get video frames as tensor
video_frames = result.frames[0]
video_tensor = torch.stack([torch.from_numpy(np.array(f)) for f in video_frames])
# get audio if available
audio = None
audio_sample_rate = None
if not args.no_audio and result.audio is not None:
audio = result.audio[0].float().cpu()
audio_sample_rate = pipe.vocoder.config.output_sampling_rate
print(f"audio generated ({audio_sample_rate}Hz)")
# export with audio
encode_video(
video=video_tensor,
fps=args.fps,
audio=audio,
audio_sample_rate=audio_sample_rate,
output_path=args.output
)
print(f"\nsaved to: {args.output}")
print(f"seed: {args.seed}")
if __name__ == "__main__":
main()