The Histogram Monitor

The histogram monitor in the Video Scopes window allows you to monitor color levels and contrast of your video. Use the histogram before rendering your project to find and correct out-of-range values that could cause problems on the destination playback device.

The bar graph plots the number of pixels that exist for each color intensity. For example, when using the Blue setting, the vertical axis represents the number of pixels, and the horizontal axis represents the RGB color range from 0,0,0 to 0,0,255.

1. Choose View | Window | Video Scopes to toggle the display of the Video Scopes window.

2. Choose Histogram from the drop-down list.

3. Choose a histogram type from the menu:

   Histogram	Description
   Luminance	Charts the luminance or brightness of colors in your video.
   Red	Charts the red tones in your video.
   Green	Charts the green tones in your video.
   Blue	Charts the blue tones in your video.
   Alpha	Charts the alpha channel (transparency) in your video.
   Luminance/R/G/B	Stacks luminance and RGB charts.
   Lightness/a/b	Stacks lightness and a/b color charts, allowing you to analyze your video in the Lab (L*a*b* or L*, a*, b*) color space. This view is especially useful with the LAB Adjust video plug-in.

4. Position the cursor in the frame you want to analyze. If the Update Scopes While Playing button is selected, you can monitor your video during playback.

5. Use the histogram to evaluate the colors in your video. The Mean value Indicates the average intensity of all pixels in the graph, and the Standard Deviation value indicates the average percentage by which pixels in the graph vary from the Mean value.

   Histogram	Description
   	Underexposed — pixels are concentrated on the left side of the graph, and the resulting image will appear unnaturally dark.
   	Banded — there are sharp changes between the shades of the selected color. The resulting image will appear to have sharp transitions between colors instead of smooth gradients.
   	High contrast — there are high concentrations of pixels in the darkest and lightest shades of the selected color with few pixels in the midtones.
   	Low contrast — most pixels are concentrated in a limited range of the selected color The resulting image will appear faded.
   	Overexposed or clipped — the lightest shades of the selected color exist in the video, and the resulting image will appear unnaturally bright and washed out.
   	Balanced — the graph is fairly well centered within the range of the selected color, with few sharp transitions between shades.