output option `-f ffmetadata` may stop the filter chain application

[Hunter Hogan]

Summary of the bug:
In some configurations, -f ffmetadata as an output option will prevent the filter chain from being applied.

---

How to reproduce:

% ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -f ffmetadata -c pcm_f32le basic_no_map.ffmeta

But, -filter_complex works:

ffmpeg -hide_banner -i test.wav -filter_complex "astats=measure_perchannel=none:measure_overall=Entropy" -f ffmetadata -c pcm_f32le complex_no_map.ffmeta

As does -f lavfi -i amovie=:

ffmpeg -hide_banner -f lavfi -i "amovie=test.wav,astats=measure_perchannel=none:measure_overall=Entropy" -f ffmetadata -c pcm_f32le lavfi_no_map.ffmeta

---

But, this triad is different:
-filter does not work:

ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -f ffmetadata basic_no_map_no_codec.ffmeta

And -filter_complex gives an error:

ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -c pcm_f32le -f ffmetadata basic_codec_ffmetadata_map_null.ffmeta -map 0 -f null -
[aost#0:0 @ 0000022a8a09aa40] Automatic encoder selection failed Default encoder for format ffmetadata (codec none) is probably disabled. Please choose an encoder manually.

But, -f lavfi -i amovie= works correctly:

ffmpeg -hide_banner -f lavfi -i "amovie=test.wav,astats=measure_perchannel=none:measure_overall=Entropy" -f ffmetadata lavfi_no_map_no_codec.ffmeta

---

The same thing happens with aspectralstats (stdout is empty):

ffmpeg -hide_banner -i test.wav -filter "aspectralstats=measure=mean,ametadata=print:file=-" -f ffmetadata -c pcm_f32le aspectralstats_basic_no_map.ffmeta

---

The same triad with signalstats:
-filter does not work:

ffmpeg -hide_banner -i test/testVideo11sec.mkv -filter "signalstats,metadata=print:file=-" -f ffmetadata signalstats_basic_no_map_no_codec.ffmeta

-filter_complex gives an error:

ffmpeg -hide_banner -i test/testVideo11sec.mkv -filter_complex "signalstats,metadata=print:file=-" -f ffmetadata signalstats_complex_no_map_no_codec.ffmeta
[vost#0:0 @ 000001c885cc8040] Automatic encoder selection failed Default encoder for format ffmetadata (codec none) is probably disabled. Please choose an encoder manually.

-f lavfi -i movie= works:

ffmpeg -hide_banner -f lavfi -i "movie=test/testVideo11sec.mkv,signalstats,metadata=print:file=-" -f ffmetadata signalstats_lavfi_no_map_no_codec.ffmeta

---

The contents of the FFmetadata file sometimes correlates with success or failure.

Success: complex_no_map.ffmeta:

;FFMETADATA1
encoder=Lavf61.3.104
[STREAM]
encoder=Lavc61.7.100 pcm_f32le
[CHAPTER]
TIMEBASE=1/48000
START=132003
END=302400
title=bike\\shed

Failure: basic_no_map.ffmeta:

;FFMETADATA1
encoder=Lavf61.3.104
[CHAPTER]
TIMEBASE=1/48000
START=132003
END=302400
title=bike\\shed

---

Can also reproduce, at a minimum, with:

ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -c pcm_f32le -f ffmetadata basic_codec_ffmetadata_map_null.ffmeta -map 0 -f null -
ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -c pcm_f32le -f ffmetadata basic_codec_map_null.ffmeta -map 0 -f null -
ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -map 0 -f ffmetadata basic_map_no_codec.ffmeta
ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -f ffmetadata basic_map_null.ffmeta -map 0 -f null -
ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -c pcm_f32le -f ffmetadata basic_no_map_codec_first.ffmeta
ffmpeg -hide_banner -i test.wav -filter "astats=measure_perchannel=none:measure_overall=Entropy" -f ffmetadata basic_no_map_no_codec.ffmeta

FFmpeg version:

ffmpeg version N-115666-gae00db87ca-g417957ec5e+3 Copyright (c) 2000-2024 the FFmpeg developers
  built with gcc 14.1.0 (Rev3, Built by MSYS2 project)
  configuration:  --pkg-config=pkgconf --cc='ccache gcc' --cxx='ccache g++' --ld='ccache g++' --extra-cxxflags=-fpermissive --extra-cflags=-Wno-int-conversion --disable-autodetect --enable-amf --enable-bzlib --enable-d3d11va --enable-dxva2 --enable-iconv --enable-lzma --enable-zlib --enable-sdl2 --enable-libmp3lame --enable-libopus --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-libdav1d --enable-libaom --disable-debug --enable-libfdk-aac --enable-fontconfig --enable-libass --enable-libfreetype --enable-libmysofa --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libwebp --enable-libxml2 --enable-libzimg --enable-libshine --enable-gpl --enable-avisynth --enable-libxvid --enable-libopenmpt --enable-version3 --enable-librav1e --enable-libsrt --enable-libgsm --enable-libvmaf --enable-libsvtav1 --enable-chromaprint   libavutil      59. 21.100 / 59. 21.100
  libavcodec     61.  7.100 / 61.  7.100
  libavformat    61.  3.104 / 61.  3.104
  libavdevice    61.  2.100 / 61.  2.100
  libavfilter    10.  2.102 / 10.  2.102
  libswscale      8.  2.100 /  8.  2.100
  libswresample   5.  2.100 /  5.  2.100
  libpostproc    58.  2.100 / 58.  2.100

[Hunter Hogan]

FFreport logs for many examples