1. What is Pixel Aspect Ratio?

Pixel Aspect Ratio (PAR) is the ratio of width to height of a single pixel in a digital image. It describes how pixels should be displayed to maintain correct proportions when the storage aspect ratio differs from the display aspect ratio.

2. How Does the Calculator Work?

The calculator uses the Pixel Aspect Ratio formula:

Where:

• Display Aspect Ratio — The intended viewing aspect ratio
• Storage Aspect Ratio — The aspect ratio of the stored image pixels

Explanation: When PAR = 1, pixels are square. When PAR ≠ 1, pixels are rectangular and need correction for proper display.

3. Importance of Pixel Aspect Ratio

Details: Correct PAR is essential for accurate image representation, especially in video production, digital imaging, and when converting between different media formats to prevent image distortion.

4. Using the Calculator

Tips: Enter both aspect ratios as decimal numbers (e.g., 1.7778 for 16:9). Both values must be greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between PAR and Display Aspect Ratio?
A: Display Aspect Ratio describes the whole image, while PAR describes the shape of individual pixels that make up that image.

Q2: When would I need to calculate PAR?
A: When working with non-square pixels in formats like DV NTSC (0.9) or PAL (1.066), or when converting between different video standards.

Q3: What does a PAR of 1 mean?
A: It means pixels are square (width equals height), which is common in computer graphics and HD video.

Q4: How does PAR affect image quality?
A: Incorrect PAR can cause images to appear stretched or squashed. Proper PAR maintains correct proportions during display.

Q5: Is PAR still relevant with modern displays?
A: While most modern displays use square pixels, PAR remains important when working with legacy formats or certain professional video workflows.