How to connect filter complex in ffmpeg?

Question

I am running the following command with an error (also below):

ffmpeg -i input.mp4 -i %04d.png -i another_input.png -filter_complex "\
  drawtext=text='Text to write':fontsize=180:fontcolor=white:x=500:y=800:enable='eq(n\,25)'[tmp];\
  [2:v]scale=20:20[ovrl];\
  [0:v][ovrl]overlay=860:500:enable='eq(n\,0)'[tmp];\
  [tmp][1:v]overlay=0:0" output.mp4

I'm receiving an error Filter drawtext has a unconnected output

I'm assuming this is where we move from the drawtext filter to the scale filter, but I'm not sure how to 'connect' the [tmp] to the scale filter while keeping drawtext first. Any help?

Solution

Use

ffmpeg -i input.mp4 -i %04d.png -i another_input.png -filter_complex "\
  [0]drawtext=text='Text to write':fontsize=180:fontcolor=white:x=500:y=800:enable='eq(n\,25)'[tmp];\
  [2:v]scale=20:20[ovrl];\
  [tmp][ovrl]overlay=860:500:enable='eq(n\,0)'[tmp1];\
  [tmp1][1:v]overlay=0:0" output.mp4

Comments

[Gyan]

On what do you want to draw the text upon? The final composite?

[user1661677]

I'd like to draw the text on [0:v], output that to [tmp], then scale/overlay [2:v] onto [tmp]

[user1661677]

Thank you. What is the reason I can't use [tmp] throughout?

[Gyan]

You could but it's not good practice to assign same label to different filterchain outputs. In any case, that's not the error in your command but that you assigned tmp as the output of two different filterchains, but did not feed the first to another filterchain before creating the second one. So it became ambiguous.