DaSiWa: Resolution Scale Calculator

The DaSiWa Scale Calculator provides mathematically precise resolution management for high-performance video models. It uses a Constant-Area Square-Root method to ensure that your GPU VRAM usage remains stable regardless of the aspect ratio.

📐 The Core Logic

Standard scalers often change the total pixel count when you change aspect ratios, leading to unexpected "Out of Memory" (OOM) errors. DaSiWa treats the resolution as a Pixel Budget (Megapixels).

Whether you are generating in 1:1 Square, 9:16 Vertical, or 21:9 Ultra-Wide, the node calculates dimensions so the total surface area remains consistent.

🚀 Key Features

WAN/LTX (Div32) Mode: Snaps calculations to the nearest 32-pixel boundary. Mandatory for WAN 2.1 and LTX-Video.
Precision Presets: Multiple tiers from 0.26 MP (Preview) to 8.30 MP (4K Production).
No Scale Toggle: A dedicated "Bypass" switch to use source image dimensions exactly.
Batch-Safe Scaling: Intelligent first-frame parsing for video and image batches.

🛠 Quick Start Guide

1. Define your "Size" (Method)

The node uses a Constant-Area formula. Instead of setting raw width/height, you set a Pixel Budget.

Precision Presets: Optimized Megapixel tiers. 0.52 MP (SD) is the baseline for most video models.
Resolution Presets: Standard targets (e.g., 1080p). The node adjusts the actual dimensions to fit your custom aspect ratio while keeping the "1080p density."

2. Define your "Shape" (Aspect Ratio)

Scale From Image (YES): The node "peeks" at the first frame of your input. It calculates the aspect ratio and applies your chosen MP budget to that specific shape.
Scale From Image (NO): Uses the Aspect Preset (e.g., 9:16) or Manual Aspect sliders.
- Note: Manual sliders define the ratio (e.g., 21 x 9), not the final pixels.

3. Choose your "Engine" (Mode)

WAN/LTX (Div32): Mandatory for Video. Forces the math to snap to the nearest 32-pixel block. This prevents VAE artifacts and edge flickering.
Standard: Use for Flux, SDXL, or SD1.5. It rounds to the nearest single pixel for maximum mathematical accuracy.

4. The "Bypass" (No Scale)

Toggle ON: Disables all calculations. The node outputs the exact width/height of the source image/manual input. Use this for native-resolution upscaling or final renders.

💡 Quick Reference Table

Goal	Method	Mode	Scale From Image?
WAN/LTX Video	Precision Presets	WAN/LTX (Div32)	YES
Flux Image	Resolution Presets	Standard	NO (Manual)
Social Media Clip	Precision Presets	WAN/LTX (Div32)	NO (Use 9:16)
Original Dims	Any	Any	No Scale: ON

2.8 KiB Raw Blame History