# Per-frame metric reports in AWS Elemental MediaConvert
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![Diagram showing per-frame metrics workflow in MediaConvert](http://docs.aws.amazon.com/mediaconvert/latest/ug/images/mediaconvert_per_frame_metrics_diagram.png)


Per-frame metric reports provide detailed video quality analysis for your MediaConvert outputs. With these reports, you can analyze your output video quality on a frame-by-frame basis by using industry-standard quality metrics.

Some use cases for per-frame metric reports might include:
+ Evaluate encoding decisions with objective quality measurements.
+ Compare different encoding settings across different outputs.
+ Identify specific frames or scenes that have low video quality.
+ Validate that your encoding settings meet quality thresholds.

MediaConvert supports the following per-frame metric types:

**PSNR (Peak Signal-to-Noise Ratio)**  
Measures the amount of noise (typically compression artifacts) after encoding. Higher values indicate better quality. Measured in decibels (dB).

**PSNR HVS (Peak Signal-to-Noise Ratio, Human Visual System)**  
A variation of PSNR that accounts for the characteristics of human visual perception. Higher values indicate better quality. Measured in decibels (dB).

**SSIM (Structural Similarity Index Measure)**  
Measures structural information like luminance, contrast, and structure. Values range from 0 to 1, with 1 indicating perfect similarity.

**MS SSIM (Multi-Scale Structural Similarity Index Measure)**  
An enhanced version of SSIM that evaluates image quality at multiple resolutions. Values range from 0 to 1, with 1 indicating perfect similarity.

**VMAF (Video Multi-Method Assessment Fusion)**  
A machine learning-based metric trained on human viewer data. VMAF can be a good indicator of viewer satisfaction for streaming video quality. Values range from 0 to 100, with higher values indicating better quality.

**QVBR (Quality-Defined Variable Bitrate)**  
Represents the QVBR quality level for an individual frame. Values range from 1 to 10. Higher values indicate better quality. This metric is only available when your output settings include the QVBR rate control mode.

**Topics**
+ [Generating per-frame metric reports](per-frame-metrics-enable.md)
+ [Metric analysis techniques](per-frame-metrics-analysis.md)
+ [Requirements and processing impact](per-frame-metrics-requirements.md)
+ [Troubleshooting](per-frame-metrics-troubleshooting.md)