is S-VHS closer to 4:1:1 or 4:2:2 ?
S-VHS (Super VHS) is an improved version of VHS that offers better video quality, especially in terms of resolution and color fidelity. While it's still an analog format, S-VHS does offer enhanced chroma resolution compared to standard VHS.
Here's how it compares to digital chroma subsampling formats like 4:1:1 and 4:2:2:
S-VHS Color Resolution
S-VHS improves upon standard VHS in several ways, including better color resolution. While it still uses a composite video signal,it provides an improvement over VHS in terms of resolution, offering around 400 lines of horizontal resolution for luminance and a slight improvement in chrominance resolution, though specific figures for chrominance resolution in S-VHS can vary. Some estimates suggest an increase to around 60-70 lines of horizontal resolution for chrominance.
Comparison to Digital Chroma Subsampling
When comparing to digital formats:
4:1:1:
- Luma: 720 pixels per line.
- Chroma: 180 pixels per line (a quarter of the luma resolution).
4:2:2:
- Luma: 720 pixels per line.
- Chroma: 360 pixels per line (half of the luma resolution).
Approximate Digital Equivalent
Given the improved chroma resolution of S-VHS compared to standard VHS, it falls somewhere between 4:1:1 and 4:2:2. Here's why:
- Chroma Resolution: While S-VHS offers better color resolution than standard VHS, it still falls short of the full 4:2:2 chroma resolution used in digital formats. However, it provides more detail than a mere quarter of the luma resolution, which is characteristic of 4:1:1.
Summary
S-VHS is closer to 4:2:2 in terms of effective color resolution compared to 4:1:1. While it doesn't match the full 4:2:2 resolution, its enhanced chroma resolution surpasses the quarter-luma resolution typically seen in 4:1:1 chroma subsampling. Therefore, S-VHS is closer to 4:2:2 than to 4:1:1, albeit still being an analog format with its own characteristics.
