Draw a graph using input video or audio metadata.
It accepts the following parameters:
- m1
-
Set 1st frame metadata key from which metadata values will be used to draw a graph.
- fg1
-
Set 1st foreground color expression.
- m2
-
Set 2nd frame metadata key from which metadata values will be used to draw a graph.
- fg2
-
Set 2nd foreground color expression.
- m3
-
Set 3rd frame metadata key from which metadata values will be used to draw a graph.
- fg3
-
Set 3rd foreground color expression.
- m4
-
Set 4th frame metadata key from which metadata values will be used to draw a graph.
- fg4
-
Set 4th foreground color expression.
- min
-
Set minimal value of metadata value.
- max
-
Set maximal value of metadata value.
- bg
-
Set graph background color. Default is white.
- mode
-
Set graph mode.
Available values for mode is:
- bar
- dot
- line
Default is
line. - 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
frame. - size
-
Set size of graph video. For the syntax of this option, check the "Video size" section in the ffmpeg-utils manual. The default value is
900x256.The foreground color expressions can use the following variables:
- MIN
-
Minimal value of metadata value.
- MAX
-
Maximal value of metadata value.
- VAL
-
Current metadata key value.
The color is defined as 0xAABBGGRR.
Example using metadata from signalstats filter:
signalstats,drawgraph=lavfi.signalstats.YAVG:min=0:max=255
Example using metadata from ebur128 filter:
ebur128=metadata=1,adrawgraph=lavfi.r128.M:min=-120:max=5