Comparison Tool

   

The V6 Comparison Tool is a simple but unique application designed to provide an easy way to directly compare 2 video clips

Right-click to load a source clip into the Master Clip panel, then load a video conversion from that clip into the Comparison Clip panel to compare videos side-by-side. Use the zoom in function and the color picker to check individual pixel values currently under the cursor for a high level quality check

Use the scrollbar under the left-hand viewer to scrub the main viewer to a frame you wish to examine. Once located, click the frame icon above the player transport controls or the frame icon located beside the Zoom check box to render frames from both videos for direct comparison

For systems with sufficient resources use the Live Scrub function to move through the source clip in real time

Each view panel contains clip info – when clip info parameters differ the label for that parameter will turn red. When parameters match the labels go green. This makes it easy to spot discrepancies between videos

Generate Metrics

You can also run metrics reports to provide automated computer analysis and quality tests. Select between SSIM or PSNR metrics

Compare Oranges to Oranges…

In order to keep your conversion analyses honest, it is best to setup the conversion (to be tested) – to convert with other-than aac audio. AAC audio formats actually embed a time offset in the video clip in order to maintain audio / video sync throughout the converted video. This may cause a delay in the first frame – which will in turn offset the analysis and consequently show false positives

You may notice a slight difference in the duration shown for source clip opposed to comparison clip. This is also an audio artifact – it is common for and audio track not to match 100% with the last video frame – causing a slight discrepancy in duration. This time should be within merely hundredths of a second – larger discrepancies may indicate other transcoding problems (extra frames, wrong framerate, etc.

When converting with the Media Command Builder you can elect to render H.264 to an MOV container – you can then select Alac or PCM audio from the drop-down audio format selector to ensure your clip lengths match