Many combinations of squeezev+easing+reverse produce access violations.

[Qriist]

I had first noticed that there was a critical issue when a file kept coming up corrupt. Ffmpeg wasn't spewing its normal error messages but instead simply exiting abruptly. I started by gathering the error code: -1073741819 (AKA 0xC0000005).

After checking my inputs I managed to narrow down the issue to transition=squeezev not cooperating with reverse=1. I looked at the front page and didn't see anything these lines. Since this seems novel I decided to do a thorough test of as many combinations as was realistic to give you proper comprehensive data. I used default values for all options where possible; I arbitrarily chose steps(4) and cubic-bezier(0.5,1.5,0.5,-0.5) for those since they required a passed value.

Anyways, the results: nearly all failed combinations occur with squeezev, though hblur had an additional single failure. All failures were access violations (as opposed to some other error code). Those error combos and the generating commands are in the table below. I've also attached a comprehensive zip of all the test results for sake of completeness.

ffmpeg-easing-error testing.zip

TRANSITION	EASING	REVERSE	ERROR
hblur	elastic	2	-1073741819
squeezev	back	1	-1073741819
squeezev	back	3	-1073741819
squeezev	bounce	1	-1073741819
squeezev	bounce	3	-1073741819
squeezev	circular	1	-1073741819
squeezev	circular	3	-1073741819
squeezev	cuberoot	1	-1073741819
squeezev	cuberoot	3	-1073741819
squeezev	cubic	1	-1073741819
squeezev	cubic	3	-1073741819
squeezev	'cubic-bezier(0.5,1.5,0.5,-0.5)'	1	-1073741819
squeezev	'cubic-bezier(0.5,1.5,0.5,-0.5)'	3	-1073741819
squeezev	ease	1	-1073741819
squeezev	ease	3	-1073741819
squeezev	ease-in	1	-1073741819
squeezev	ease-in	3	-1073741819
squeezev	ease-in-out	1	-1073741819
squeezev	ease-in-out	3	-1073741819
squeezev	ease-out	1	-1073741819
squeezev	ease-out	3	-1073741819
squeezev	exponential	1	-1073741819
squeezev	exponential	3	-1073741819
squeezev	quadratic	1	-1073741819
squeezev	quadratic	3	-1073741819
squeezev	quartic	0	-1073741819
squeezev	quartic	1	-1073741819
squeezev	quartic	2	-1073741819
squeezev	quartic	3	-1073741819
squeezev	quintic	0	-1073741819
squeezev	quintic	1	-1073741819
squeezev	quintic	2	-1073741819
squeezev	quintic	3	-1073741819
squeezev	sinusoidal	1	-1073741819
squeezev	sinusoidal	3	-1073741819
squeezev	squareroot	1	-1073741819
squeezev	squareroot	3	-1073741819
squeezev	step-end	1	-1073741819
squeezev	step-end	2	-1073741819
squeezev	step-end	3	-1073741819
squeezev	step-start	0	-1073741819
squeezev	step-start	3	-1073741819
squeezev	steps(4)	1	-1073741819
squeezev	steps(4)	2	-1073741819
squeezev	steps(4)	3	-1073741819

ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=hblur:easing=elastic:reverse=2:duration=3:offset=5[vout] -map "[vout]" output\hblur_elastic_2.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=back:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_back_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=back:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_back_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=bounce:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_bounce_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=bounce:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_bounce_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=circular:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_circular_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=circular:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_circular_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=cuberoot:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_cuberoot_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=cuberoot:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_cuberoot_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=cubic:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_cubic_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=cubic:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_cubic_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing='cubic-bezier(0.5,1.5,0.5,-0.5)':reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_'cubic-bezier(0.5,1.5,0.5,-0.5)'_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing='cubic-bezier(0.5,1.5,0.5,-0.5)':reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_'cubic-bezier(0.5,1.5,0.5,-0.5)'_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease-in:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease-in_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease-in:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease-in_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease-in-out:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease-in-out_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease-in-out:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease-in-out_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease-out:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease-out_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=ease-out:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_ease-out_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=exponential:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_exponential_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=exponential:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_exponential_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quadratic:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quadratic_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quadratic:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quadratic_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quartic:reverse=0:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quartic_0.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quartic:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quartic_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quartic:reverse=2:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quartic_2.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quartic:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quartic_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quintic:reverse=0:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quintic_0.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quintic:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quintic_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quintic:reverse=2:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quintic_2.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=quintic:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_quintic_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=sinusoidal:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_sinusoidal_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=sinusoidal:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_sinusoidal_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=squareroot:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_squareroot_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=squareroot:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_squareroot_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=step-end:reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_step-end_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=step-end:reverse=2:duration=3:offset=5[vout] -map "[vout]" output\squeezev_step-end_2.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=step-end:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_step-end_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=step-start:reverse=0:duration=3:offset=5[vout] -map "[vout]" output\squeezev_step-start_0.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=step-start:reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_step-start_3.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=steps(4):reverse=1:duration=3:offset=5[vout] -map "[vout]" output\squeezev_steps(4)_1.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=steps(4):reverse=2:duration=3:offset=5[vout] -map "[vout]" output\squeezev_steps(4)_2.mp4
ffmpeg-easing\ffmpeg-easing.exe -hide_banner -loglevel error -y -i input\input1_lowres.mp4 -i input\input2_lowres.mp4 -filter_complex [0:v][1:v]xfade=transition=squeezev:easing=steps(4):reverse=3:duration=3:offset=5[vout] -map "[vout]" output\squeezev_steps(4)_3.mp4

Sorry the ticket's so complex, but hopefully it was helpful.

[scriptituk]

Wow! You really expose my inadequate Windows testing.

I can see the problems with blur & squeeze built-in transitions:

• elastic & back easings cause Progress overshoots which need clipping for Xfade because it accesses plane data without limit checks
• sqeezev & squeezeh have a divide-by-zero scenario when Progress is zero
• plain vanilla ffmpeg never sets Progress to zero, it's minimum value is 1/num_duration_frames
• the easing and reverse options do cause Progress to equal zero

Please can you send me the output from ffmpeg-easing.exe -buildconf.

Many thanks for your time on this. It forces an overshoot strategy and protection traps for built-in transitions.

[Qriist]

Wow! You really expose my inadequate Windows testing.

No worries at all, can't test what you don't have. :D

• sqeezev & squeezeh have a divide-by-zero scenario when Progress is zero

it's interesting squeezeh didn't appear in the test fails. Perhaps this particular scenario is caught elsewhere?

Many thanks for your time on this. It forces an overshoot strategy and protection traps for built-in transitions.

The pleasure is mine. I really appreciate you troubleshooting for a system you don't even use. 😅

Please can you send me the output from ffmpeg-easing.exe -buildconf.

You got it!

ffmpeg version 8.0.1-scriptituk/ffmpeg-makexe Copyright (c) 2000-2025 the FFmpeg developers
  built with clang version 21.1.7
  configuration: --extra-version=scriptituk/ffmpeg-makexe --prefix=/opt/scriptituk/clang64 --shlibdir=/opt/scriptituk/clang64/so --target-os=mingw32 --arch=x86_64 --cc=clang --cxx=clang++ --disable-static --enable-shared --disable-debug --disable-ffplay --disable-doc --enable-dxva2 --enable-d3d11va --enable-d3d12va --enable-frei0r --enable-gmp --enable-gnutls --enable-gpl --enable-iconv --enable-libaom --enable-libass --enable-libbluray --enable-libcaca --enable-libdav1d --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libharfbuzz --enable-libjxl --enable-libmodplug --enable-libmp3lame --enable-libopencore_amrnb --enable-libopencore_amrwb --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libssh --enable-libsoxr --enable-libspeex --enable-libsrt --enable-libtheora --enable-libvidstab --enable-libvorbis --enable-libx264 --enable-libx265 --enable-libxvid --enable-libvpx --enable-libwebp --enable-libxml2 --enable-libzimg --enable-libzvbi --enable-openal --enable-pic --enable-runtime-cpudetect --enable-swresample --enable-version3 --enable-zlib --enable-libvpl --enable-liblc3 --enable-librav1e --enable-librsvg --enable-libsvtav1 --enable-libshaderc
  libavutil      60.  8.100 / 60.  8.100
  libavcodec     62. 11.100 / 62. 11.100
  libavformat    62.  3.100 / 62.  3.100
  libavdevice    62.  1.100 / 62.  1.100
  libavfilter    11.  4.100 / 11.  4.100
  libswscale      9.  1.100 /  9.  1.100
  libswresample   6.  1.100 /  6.  1.100

  configuration:
    --extra-version=scriptituk/ffmpeg-makexe
    --prefix=/opt/scriptituk/clang64
    --shlibdir=/opt/scriptituk/clang64/so
    --target-os=mingw32
    --arch=x86_64
    --cc=clang
    --cxx=clang++
    --disable-static
    --enable-shared
    --disable-debug
    --disable-ffplay
    --disable-doc
    --enable-dxva2
    --enable-d3d11va
    --enable-d3d12va
    --enable-frei0r
    --enable-gmp
    --enable-gnutls
    --enable-gpl
    --enable-iconv
    --enable-libaom
    --enable-libass
    --enable-libbluray
    --enable-libcaca
    --enable-libdav1d
    --enable-libfontconfig
    --enable-libfreetype
    --enable-libfribidi
    --enable-libgme
    --enable-libgsm
    --enable-libharfbuzz
    --enable-libjxl
    --enable-libmodplug
    --enable-libmp3lame
    --enable-libopencore_amrnb
    --enable-libopencore_amrwb
    --enable-libopenjpeg
    --enable-libopus
    --enable-librtmp
    --enable-libssh
    --enable-libsoxr
    --enable-libspeex
    --enable-libsrt
    --enable-libtheora
    --enable-libvidstab
    --enable-libvorbis
    --enable-libx264
    --enable-libx265
    --enable-libxvid
    --enable-libvpx
    --enable-libwebp
    --enable-libxml2
    --enable-libzimg
    --enable-libzvbi
    --enable-openal
    --enable-pic
    --enable-runtime-cpudetect
    --enable-swresample
    --enable-version3
    --enable-zlib
    --enable-libvpl
    --enable-liblc3
    --enable-librav1e
    --enable-librsvg
    --enable-libsvtav1
    --enable-libshaderc

Exiting with exit code 0