<p>I've two files, a <code>mp4</code> and a <code>mp3</code> file. I want to add a <code>3</code> seconds intro screen with title <code>Welcome</code> and <code>black</code> background to the head of the video with the <code>mp3</code> as background. So here's what I wrote.</p>

<pre><code>ffmpeg \
    -i input.mp4 \
    -i bgm.mp3 \
    -f lavfi -i color=c=black:s="1280"x"544":d=3.0 \
    -filter_complex \
        "[2:v]
  drawtext=
    fontsize=30
    :fontcolor=white
    :x=(w-text_w)/2
    :y=(h-text_h)/2
    :text='WELCOME'
[introVideo];

[1:a]
    atrim=0.0:3.0
[introAudio];

[introVideo][introAudio][0:v][0:a]concat=n=2:v=1:a=1" -preset superfast output.mp4
</code></pre>

<p>but am getting below error when I try to execute the command</p>

<pre><code>[Parsed_concat_3 @ 0x55c02756fa00] Input link in1:v0 parameters (size 1280x544, SAR 1299:1280) do not match the corresponding output link in0:v0 parameters (1280x544, SAR 1:1)
[Parsed_concat_3 @ 0x55c02756fa00] Failed to configure output pad on Parsed_concat_3
Error reinitializing filters!
Failed to inject frame into filter network: Invalid argument
Error while processing the decoded data for stream #0:1
Conversion failed!
</code></pre>

<p>Any help will be highly appreciated.</p>

<p>PS: I am a beginner in video processing and <code>ffmpeg</code>.</p>

CC BY-SA 4.0
2020-03-01T13:58:15.430Z
See 2nd command in answer at duplicate link.
Gyan
CC BY-SA 4.0
2020-03-01T18:12:04.657Z
@Gyan: running concat with `unsafe` flag seems not recommended. Is it possible to set the aspect ratio of input video to `-f lavfi -i color...` ?
theapache64
CC BY-SA 4.0
2020-03-01T18:33:49.800Z
Insert `[0:v]setsar=1[0v];` before the concat filter, and use label `0v` in place of `0:v` in concat.
Gyan
CC BY-SA 4.0
2020-03-01T18:41:38.133Z
Oh my god, it worked. One more doubt @Gyan. What If I don't want to change `sar` of `input` but want to change `sar` of `[2:v]` to `sar` of  `0:v` ?
theapache64
CC BY-SA 4.0
2020-03-01T18:48:45.397Z
Then insert setsar for 2v after the final filter (geq).
Gyan
CC BY-SA 4.0
2020-03-01T18:52:38.397Z
@Gyan `setsar` with value `1` ?
theapache64
CC BY-SA 4.0
2020-03-01T18:53:35.897Z
Let us [continue this discussion in chat](https://chat.stackexchange.com/rooms/105059/discussion-between-theapache64-and-gyan).
theapache64
CC BY-SA 4.0
2020-03-01T19:10:11.607Z
No, with the SAR value for 0:v - 1299:1280
Gyan
CC BY-SA 4.0
2020-03-01T19:14:30.840Z
I tried with `setsar=1299/1280`, but am getting same error. :( @Gyan
theapache64
CC BY-SA 4.0
2020-03-02T05:03:13.403Z
@Gyan Do you know why it's not working ?
theapache64
<ffmpeg>
Input link in1:v0 parameters (size XXX, SAR XXX) do not match the corresponding output link in0:v0 parameters (XXX, SAR 1:1)
theapache64
# Input link in1:v0 parameters (size XXX, SAR XXX) do not match the corresponding output link in0:v0 parameters (XXX, SAR 1:1)

(Asked by: username_0 on 2020-03-01)

I've two files, a mp4 and a mp3 file. I want to add a 3 seconds intro screen with title Welcome and black background to the head of the video with the mp3 as background. So here's what I wrote.
ffmpeg \
    -i input.mp4 \
    -i bgm.mp3 \
    -f lavfi -i color=c=black:s="1280"x"544":d=3.0 \
    -filter_complex \
        "[2:v]
  drawtext=
    fontsize=30
    :fontcolor=white
    :x=(w-text_w)/2
    :y=(h-text_h)/2
    :text='WELCOME'
[introVideo];

[1:a]
    atrim=0.0:3.0
[introAudio];

[introVideo][introAudio][0:v][0:a]concat=n=2:v=1:a=1" -preset superfast output.mp4

but am getting below error when I try to execute the command
[Parsed_concat_3 @ 0x55c02756fa00] Input link in1:v0 parameters (size 1280x544, SAR 1299:1280) do not match the corresponding output link in0:v0 parameters (1280x544, SAR 1:1)
[Parsed_concat_3 @ 0x55c02756fa00] Failed to configure output pad on Parsed_concat_3
Error reinitializing filters!
Failed to inject frame into filter network: Invalid argument
Error while processing the decoded data for stream #0:1
Conversion failed!

Any help will be highly appreciated.
PS: I am a beginner in video processing and ffmpeg.

**Tags:** ffmpeg

> **Comments:**
> **username_1**: See 2nd command in answer at duplicate link.  
> **username_0**: @username_1: running concat with `unsafe` flag seems not recommended. Is it possible to set the aspect ratio of input video to `-f lavfi -i color...` ?  
> **username_1**: Insert `[0:v]setsar=1[0v];` before the concat filter, and use label `0v` in place of `0:v` in concat.  
> **username_0**: Oh my god, it worked. One more doubt @username_1. What If I don't want to change `sar` of `input` but want to change `sar` of `[2:v]` to `sar` of  `0:v` ?  
> **username_1**: Then insert setsar for 2v after the final filter (geq).  
> **username_0**: @username_1 `setsar` with value `1` ?  
> **username_0**: Let us [continue this discussion in chat](https://chat.stackexchange.com/rooms/105059/discussion-between-username_0-and-gyan).  
> **username_1**: No, with the SAR value for 0:v - 1299:1280  
> **username_0**: I tried with `setsar=1299/1280`, but am getting same error. :( @username_1  
> **username_0**: @username_1 Do you know why it's not working ?  

---

## 0 answers

