On Sat, Apr 11, 2020 at 23:03:31 +0200, Michael Koch wrote:
I want to show the content of a credits file scrolling up.The file
contains many lines of different lengths.
drawtext=textfile=credits.txt:x=(w-text_w)/2:y=h-100*t
The variable text_w is the width of the longest line in the text file.
This line is center-aligned in the frame, and all other (shorter) lines
are left-aligned to the same X position as the longest line.
But that's not what I want. Is it somehow possible that each line is
center-aligned?
I can't answer your question, unfortunately, but how about an
alternative? You can write your credits as ASS subtitles, and have
ffmpeg render them on top of your video.
The example I retrieved here:
http://forum.doom9.org/showthread.php?t=82025
works just fine.
Use this as credits.ass:
---snip---
[Script Info]
ScriptType: v4.00+
Collisions: Normal
PlayResX: 640
PlayResY: 480
Timer: 100.0000
[V4+ Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour,
OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY,
Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR,
MarginV, Encoding
Style:
testStyle,Verdana,24,&H4099ffff,&H00000000,&Hc0000000,&H00000000,-1,0,0,0,100,100,0,0.00,1,1,0,8,0,0,0,0
[Events]
Format: Layer, Start, End, Style, Actor, MarginL, MarginR, MarginV, Effect, Text
Dialogue:
0,0:00:02.00,0:00:12.00,testStyle,,0000,0000,0000,,{\move(320,400,320,80)}{\fad(1000,1000)}Foo
bar
Dialogue:
0,0:00:04.00,0:00:14.00,testStyle,,0000,0000,0000,,{\move(320,400,320,80)}{\fad(1000,1000)}Baz
Dialogue:
0,0:00:06.00,0:00:16.00,testStyle,,0000,0000,0000,,{\move(320,400,320,80)}{\fad(1000,1000)}Qux
quux quuux
Dialogue:
0,0:00:08.00,0:00:18.00,testStyle,,0000,0000,0000,,{\move(320,400,320,80)}{\fad(1000,1000)}Xyzzy
---snip---
and overlay it onto your video:
$ ffmpeg -f lavfi -i testsrc=s=640x480 -vf subtitles=credits.ass -f nut - |
ffplay -
ASS is tricky to create manually, but you might figure out the concept
from the example, or use a tool to create them.
