Add text overlay with timestamp

video filters

// what it does

`drawtext` burns text into the frame; `text='%{pts\:hms}'` prints each frame's presentation timestamp formatted as `H:MM:SS.mmm` via the `hms` modifier, so every frame is stamped with its own time. `x=10:y=10` pins it near the top-left with a small margin, and `fontsize`/`fontcolor` control appearance. Useful for timecoded review copies or debugging A/V sync.

// shell

$ ffmpeg -i input.mp4 -vf "drawtext=text='%{pts\:hms}':x=10:y=10:fontsize=24:fontcolor=white" output.mp4

// gotcha

`drawtext` requires an ffmpeg built with libfreetype; on a build without fontconfig it can't resolve a default font and aborts, so pass an explicit `fontfile=/path/to/font.ttf`. The colon inside `%{pts:hms}` must stay escaped as `\:`, or the filtergraph parser treats it as an option separator.