<p>Your command is missing the <code>-i</code> token for the image input, so it should be</p>

<pre><code>ffmpeg -loop 1 -framerate 24 -t 10 -i image.jpg -f lavfi ...
</code></pre>

<p>However, for the actual task at hand, the concat filter is not required.</p>

<pre><code>ffmpeg -loop 1 -framerate 24 -t 10 -i image.jpg -f lavfi -t 10 -i anullsrc out.mp4
</code></pre>

CC BY-SA 4.0
2020-04-01T15:01:36.373Z
ffmpeg -loop 1 -framerate 24 -t 10 -i beach.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0:v][1:a]concat=n=2:v=1:a=1" out.mp4
Dave
CC BY-SA 4.0
2020-04-01T15:02:03.230Z
but still I get "Cannot find a matching stream for unlabeled input pad 2 on filter Parsed_concat_0"
Dave
CC BY-SA 4.0
2020-04-01T15:10:40.527Z
Edited answer..
Gyan
CC BY-SA 4.0
2020-04-01T15:21:22.597Z
I need to use the complex filter as there are few more filters I am using in the pipeline, this was just part of it with multiple inputs.
Dave
CC BY-SA 4.0
2020-04-01T15:23:18.517Z
Then you should have shown your actual command.
Gyan
CC BY-SA 4.0
2020-04-01T14:23:27.903Z
2020-04-01T15:08:07.887Z
2020-04-01T15:08:07.887Z
Gyan
<p>I am generating 10 seconds of silence using an image. Here is my command</p>

<pre><code>ffmpeg -loop 1 -framerate 24 -t 10 image.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0][1]concat=n=2:v=1:a=1" out.mp4
</code></pre>

<p>Also, I have tried </p>

<pre><code>ffmpeg -loop 1 -framerate 24 -t 10 beach.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0:v][1:a]concat=n=2:v=1:a=1" out.mp4
</code></pre>

<p>I am getting following errors</p>

<pre><code>ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
  built with Apple clang version 11.0.0 (clang-1100.0.33.17)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.2.2_2 --enable-shared --enable-pthreads --enable-version3 --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-libsoxr --enable-videotoolbox --disable-libjack --disable-indev=jack
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Input #0, lavfi, from 'anullsrc':
  Duration: N/A, start: 0.000000, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_u8, 44100 Hz, stereo, u8, 705 kb/s
Stream specifier '' in filtergraph description [0][1]concat=n=2:v=1:a=1 matches no streams.

ffmpeg -loop 1 -framerate 24 -t 10 beach.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0:v][1:a]concat=n=2:v=1:a=1" out.mp4
ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
  built with Apple clang version 11.0.0 (clang-1100.0.33.17)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.2.2_2 --enable-shared --enable-pthreads --enable-version3 --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-libsoxr --enable-videotoolbox --disable-libjack --disable-indev=jack
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Input #0, lavfi, from 'anullsrc':
  Duration: N/A, start: 0.000000, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_u8, 44100 Hz, stereo, u8, 705 kb/s
Stream specifier ':v' in filtergraph description [0:v][1:a]concat=n=2:v=1:a=1 matches no streams.
</code></pre>

<ffmpeg>
I am getting "Stream specifier ' ' in filtergraph description" in ffmpeg
Dave
# I am getting "Stream specifier ' ' in filtergraph description" in ffmpeg

(Asked by: username_0 on 2020-04-01)

I am generating 10 seconds of silence using an image. Here is my command
ffmpeg -loop 1 -framerate 24 -t 10 image.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0][1]concat=n=2:v=1:a=1" out.mp4

Also, I have tried 
ffmpeg -loop 1 -framerate 24 -t 10 beach.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0:v][1:a]concat=n=2:v=1:a=1" out.mp4

I am getting following errors
ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
  built with Apple clang version 11.0.0 (clang-1100.0.33.17)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.2.2_2 --enable-shared --enable-pthreads --enable-version3 --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-libsoxr --enable-videotoolbox --disable-libjack --disable-indev=jack
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Input #0, lavfi, from 'anullsrc':
  Duration: N/A, start: 0.000000, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_u8, 44100 Hz, stereo, u8, 705 kb/s
Stream specifier '' in filtergraph description [0][1]concat=n=2:v=1:a=1 matches no streams.

ffmpeg -loop 1 -framerate 24 -t 10 beach.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0:v][1:a]concat=n=2:v=1:a=1" out.mp4
ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
  built with Apple clang version 11.0.0 (clang-1100.0.33.17)
  configuration: --prefix=/usr/local/Cellar/ffmpeg/4.2.2_2 --enable-shared --enable-pthreads --enable-version3 --enable-avresample --cc=clang --host-cflags= --host-ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librubberband --enable-libsnappy --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxvid --enable-lzma --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-librtmp --enable-libspeex --enable-libsoxr --enable-videotoolbox --disable-libjack --disable-indev=jack
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libavresample   4.  0.  0 /  4.  0.  0
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Input #0, lavfi, from 'anullsrc':
  Duration: N/A, start: 0.000000, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_u8, 44100 Hz, stereo, u8, 705 kb/s
Stream specifier ':v' in filtergraph description [0:v][1:a]concat=n=2:v=1:a=1 matches no streams.

**Tags:** ffmpeg


---

## 1 answers

### Answer by username_1 on 2020-04-01. Score: 0

Your command is missing the -i token for the image input, so it should be
ffmpeg -loop 1 -framerate 24 -t 10 -i image.jpg -f lavfi ...

However, for the actual task at hand, the concat filter is not required.
ffmpeg -loop 1 -framerate 24 -t 10 -i image.jpg -f lavfi -t 10 -i anullsrc out.mp4

> **Comments:**
> **username_0**: ffmpeg -loop 1 -framerate 24 -t 10 -i beach.jpg -f lavfi -t 10 -i anullsrc -filter_complex "[0:v][1:a]concat=n=2:v=1:a=1" out.mp4  
> **username_0**: but still I get "Cannot find a matching stream for unlabeled input pad 2 on filter Parsed_concat_0"  
> **username_1**: Edited answer..  
> **username_0**: I need to use the complex filter as there are few more filters I am using in the pipeline, this was just part of it with multiple inputs.  
> **username_1**: Then you should have shown your actual command.  

---

