Image Quality & Compression AnalyzerSSIM & PSNR
Algorithmic pixel difference inspector, split-curtain comparison, and visual fidelity audit.
Reference Original
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PNG, JPG, WEBP, AVIF or click to browse
Compressed / Target
Choose Target Image
PNG, JPG, WEBP, AVIF or click to browse
Understanding Image Fidelity Metrics
SSIM (Structural Similarity Index): Models human visual perception by measuring luminance, contrast, and structural covariance in 8x8 pixel blocks. Scores > 98% are considered visually imperceptible to the naked eye.
PSNR (Peak Signal-to-Noise Ratio): The standard logarithmic decibel metric between maximum pixel energy and Mean Squared Error. 35–45 dB represents standard web/mobile production quality; > 50 dB is reference studio grade.
RMSE & Difference Heatmaps: Highlights localized high-frequency loss such as ringing around fine text, block boundaries in JPEG DCT quantization tables, and subtle color desaturation.