ffm_drawbox: Draw a Colored Box on the Videos in an FFmpeg Pipeline

In tidymedia: Media File Preprocessing and Metadata for the 'tidyverse'

Draw a Colored Box on the Videos in an FFmpeg Pipeline

Description

Add a video filter that draws a colored rectangle on the input video.

Usage

ffm_drawbox(
  object,
  x = 0,
  y = 0,
  width = "in_w",
  height = "in_h",
  color = "black",
  thickness = "fill"
)

Arguments

object	An FFmpeg pipeline (ffm) object created by ffm_files().
x	The horizontal position of the left edge of the box, in pixels of the input video. Give a nonnegative real number or a string that contains an FFmpeg expression. The default is 0.
y	The vertical position of the top edge of the box, in pixels of the input video. Give a nonnegative real number or a string that contains an FFmpeg expression. The default is 0.
width	The width of the box, in pixels. Give a positive real number or a string that contains an FFmpeg expression. The default is "in_w".
height	The height of the box, in pixels. Give a positive real number or a string that contains an FFmpeg expression. The default is "in_h".
color	A string with the color of the box, in FFmpeg color syntax. The reference link below explains that syntax. With the special value "invert", the box has the color of the video with inverted luma. The default is "black".
thickness	The thickness of the box edge, in pixels. The value "fill" draws a filled box. The default is "fill".

Value

object with an added instruction to apply the drawbox filter.

References

https://ffmpeg.org/ffmpeg-filters.html#drawbox

https://ffmpeg.org/ffmpeg-utils.html#color-syntax

See Also

anonymize_video(), the task function that uses ffm_drawbox() to fill regions.

Other pipeline functions: ffm_batch(), ffm_codec(), ffm_compile(), ffm_concat(), ffm_copy(), ffm_crop(), ffm_drop(), ffm_files(), ffm_fps(), ffm_hstack(), ffm_jobs(), ffm_loudnorm(), ffm_map(), ffm_output_options(), ffm_overlay(), ffm_pixel_format(), ffm_run(), ffm_scale(), ffm_seek(), ffm_trim(), ffm_vstack(), print.tidymedia_ffm()

Examples

video <- system.file("extdata", "sample.mp4", package = "tidymedia")
# Draw a filled red box covering the top-left quarter of the frame
ffm_files(video, "output.mp4") |>
  ffm_drawbox(width = "in_w/2", height = "in_h/2", color = "red") |>
  ffm_compile()

tidymedia documentation built on Oct. 11, 2026, 5:08 p.m.