Compute and draw a color distribution histogram for the input video across time.

Unlike histogram video filter which only shows histogram of single input frame at certain time, this filter shows also past histograms of number of frames defined by width option.

The computed histogram is a representation of the color component distribution in an image.

The filter accepts the following options:

width, w

Set width of single color component output. Default value is 0. Value of 0 means width will be picked from input video. This also set number of passed histograms to keep. Allowed range is [0, 8192].

display_mode, d

Set display mode. It accepts the following values:

stack

Per color component graphs are placed below each other.

parade

Per color component graphs are placed side by side.

overlay

Presents information identical to that in the parade, except that the graphs representing color components are superimposed directly over one another.

Default is stack.

levels_mode, m

Set mode. Can be either linear, or logarithmic. Default is linear.

components, c

Set what color components to display. Default is 7.

bgopacity, b

Set background opacity. Default is 0.9.

envelope, e

Show envelope. Default is disabled.

ecolor, ec

Set envelope color. Default is gold.

slide

Set slide mode.

Available values for slide is:

frame

Draw new frame when right border is reached.

replace

Replace old columns with new ones.

scroll

Scroll from right to left.

rscroll

Scroll from left to right.

picture

Draw single picture.

Default is replace.