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videotextffmpeg

ffmpeg create blank screen with text video

I would like to create a video consisting of some text. The video will only be 0.5 seconds long. The background should just be some colour, I am able to create such video from a photo, but cant find anywhere how this could be done without a photo, just using text to create such video.

Solution

  • drawtext vs subtitles

    This can be done using the drawtext or subtitles filters.

    drawtext is simpler, but subtitles has much better styling and timing options. subtitles can automatically wrap the text while drawtext cannot.

    drawtext filter examples

    Add text to solid color background

    enter image description here

    Using the color filter for the background and the drawtext filter for the text. Example for a 320x240, 10 second, 25 fps, blue background. Text is size 30, colored white, and centered.

    ffmpeg -f lavfi -i color=size=320x240:duration=10:rate=25:color=blue -vf "drawtext=fontfile=/path/to/font.ttf:fontsize=30:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2:text='Stack Overflow'" output.mp4

    With audio file

    Same as above, but video will automatically match audio duration by removing duration=10 and adding -shortest:

    ffmpeg -f lavfi -i color=size=320x240:rate=25:color=blue -i audio.m4a -vf "drawtext=fontfile=/path/to/font.ttf:fontsize=30:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2:text='Stack Overflow'" -c:a copy -shortest output.mp4

    With a transparent box behind text

    Another example with a white box behind the text at 25% opacity with 5 pixel padding:

    enter image description here

    ffmpeg -f lavfi -i color=c=red:s=320x240:d=10 -vf "drawtext=fontfile=/path/to/font.ttf:fontsize=30:box=1:boxborderw=5:[email protected]:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2:text='Stack Overflow'" output.mp4

    Multiple lines

    enter image description here enter image description here
    It's easier to center the two lines with multiple drawtext instances (left image). Right image is from the external file and line break examples.

    There are 3 methods. You can chain together two drawtext filters, or reference an external text file with the textfile option, or add the line break in the command.

    Alternatively, see the example below using the subtitles filter. This filter will automatically wrap long text.

    Method 1: Multiple drawtext instances

    ffmpeg -f lavfi -i color=c=green:s=320x240:d=10 -vf "drawtext=fontfile=/path/to/font.ttf:fontsize=30:fontcolor=white:x=(w-text_w)/2:y=(h-text_h-text_h)/2:text='Stack',drawtext=fontfile=/path/to/font.ttf:fontsize=30:fontcolor=white:x=(w-text_w)/2:y=(h+text_h)/2:text='Overflow'" output.mp4

    Method 2: External text file

    The contents of the text file, text.txt, looks like this:

    Stack
Overflow

    The ffmpeg command:

    ffmpeg -f lavfi -i color=c=green:s=320x240:d=0.5 -vf "drawtext=fontfile=/path/to/font.ttf:fontsize=30:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2:textfile=text.txt" output.mp4

    Method 3: Line break in command

    ffmpeg -f lavfi -i color=c=green:s=320x240:d=0.5 -vf "drawtext=fontfile=/path/to/font.ttf:fontsize=30:fontcolor=white:x=(w-text_w)/2:y=(h-text_h)/2:text='Stack
Overflow'" output.mp4

    Positions

    • Top left: x=0:y=0 (with 10 pixel padding x=10:y=10)
    • Top center: x=(w-text_w)/2:y=0 (with 10 px padding x=(w-text_w)/2:y=10)
    • Top right: x=w-tw:y=0 (with 10 px padding: x=w-tw-10:y=10)
    • Centered: x=(w-text_w)/2:y=(h-text_h)/2
    • Bottom left: x=0:y=h-th (with 10 px padding: x=10:y=h-th-10)
    • Bottom center: x=(w-text_w)/2:y=h-th (with 10 px padding: x=(w-text_w)/2:y=h-th-10)
    • Bottom right: x=w-tw:y=h-th (with 10 px padding: x=w-tw-10:y=h-th-10)

    subtitles filter example with audio

    Using the color filter for the background and the subtitles filter for the text.

    First, create SRT (SubRip) file. This example sets the duration to 10 hours. The duration doesn't really matter: it just needs to be longer than the audio file duration.

    1
00:00:00,000 --> 10:00:00,000
Stack Overflow

    Then run ffmpeg:

    ffmpeg -f lavfi -i color=size=256x144:rate=15:color=blue -i "Audio File.m4a" -vf "subtitles=subtitles.srt:force_style='Alignment=10,Fontsize=30'" -c:a copy -movflags +faststart -shortest output.mp4

    • Alternatively, use Aegisub to create ASS (Advanced SubStation Alpha) subtitles and you won't have to use force_style. Downside is that ASS is a much more complicated format than SRT.

    • If you want to use force_style refer to the Format and Style lines in an ASS file to get an idea of how to use more force_style options, and also see Aegisub Manual - Ass Tags for advanced formatting.

    Output image instead of video

    If you want an image output instead replace output.mp4 with -frames:v 1 output.png.