Crashes after playing large .mkv file for a few seconds

[promitheas17j]

This tracker is for defects only! For feature requests, see our discussion forum.

OS and Version (please complete the following information):

• Operating System: Arch Linux 6.17.2-arch1-1
• Shotcut Version: Shotcut 25.08.16 installed through the Arch extra repository.

Describe the bug
A clear and concise description of what the bug is.

I have a recording of around 4.5 hours recorded through OBS. The output format is mkv. When I create a new project and import this file into shotcut so I can start editing, I get a crash after less than a minute of simply playing the file in the player.

Steps To Reproduce

1. Start Shotcut
2. Import file
3. Add it to playlist
4. Play the file
5. Will start to lag and eventually crash after a short time

Expected behavior
I should be able to play the file at the very least without it crashing, let alone making basic edits.

Screenshots
If applicable, add screenshots to help explain your problem.

Can't really screenshot the problem, but I'd be happy to provide any additional info like logs if required.

This is all I get if I run shotcut through the terminal:

shotcut
libDeckLinkAPI.so: cannot open shared object file: No such file or directory
---
formats:
  - a64
  - ac3
  - ac4
  - adts
  - adx
  - aea
  - aiff
  - alp
  - amr
  - amv
  - apm
  - apng
  - aptx
  - aptx_hd
  - apv
  - argo_asf
  - argo_cvg
  - asf
  - ass
  - ast
  - asf_stream
  - au
  - avi
  - avif
  - avm2
  - avs2
  - avs3
  - bit
  - caf
  - cavsvideo
  - codec2
  - codec2raw
  - crc
  - dash
  - data
  - daud
  - dfpwm
  - dirac
  - dnxhd
  - dts
  - dv
  - eac3
  - evc
  - f4v
  - ffmetadata
  - fifo
  - filmstrip
  - fits
  - flac
  - flv
  - framecrc
  - framehash
  - framemd5
  - g722
  - g723_1
  - g726
  - g726le
  - gif
  - gsm
  - gxf
  - h261
  - h263
  - h264
  - hash
  - hds
  - hevc
  - hls
  - iamf
  - ico
  - ilbc
  - image2
  - image2pipe
  - ipod
  - ircam
  - ismv
  - ivf
  - jacosub
  - kvag
  - latm
  - lc3
  - lrc
  - m4v
  - mcc
  - md5
  - matroska
  - matroska
  - microdvd
  - mjpeg
  - mlp
  - mmf
  - mov
  - mp2
  - mp3
  - mp4
  - mpeg
  - vcd
  - mpeg1video
  - dvd
  - svcd
  - mpeg2video
  - vob
  - mpegts
  - mpjpeg
  - mxf
  - mxf_d10
  - mxf_opatom
  - null
  - nut
  - obu
  - oga
  - ogg
  - ogv
  - oma
  - opus
  - alaw
  - mulaw
  - vidc
  - f64be
  - f64le
  - f32be
  - f32le
  - s32be
  - s32le
  - s24be
  - s24le
  - s16be
  - s16le
  - s8
  - u32be
  - u32le
  - u24be
  - u24le
  - u16be
  - u16le
  - u8
  - psp
  - rawvideo
  - rcwt
  - rm
  - roq
  - rso
  - rtp
  - rtp_mpegts
  - rtsp
  - sap
  - sbc
  - scc
  - film_cpk
  - segment
  - stream_segment,ssegment
  - smjpeg
  - smoothstreaming
  - sox
  - spx
  - spdif
  - srt
  - streamhash
  - sup
  - swf
  - tee
  - 3g2
  - 3gp
  - mkvtimestamp_v2
  - truehd
  - tta
  - ttml
  - uncodedframecrc
  - vc1
  - vc1test
  - voc
  - vvc
  - w64
  - wav
  - webm
  - webm_dash_manifest
  - webm_chunk
  - webp
  - webvtt
  - wsaud
  - wtv
  - wv
  - yuv4mpegpipe
  - alsa
  - fbdev
  - oss
  - pulse
  - video4linux2,v4l2
  - xv
...
---
audio_codecs:
  - comfortnoise
  - s302m
  - aac
  - ac3
  - ac3_fixed
  - alac
  - aptx
  - aptx_hd
  - dca
  - dfpwm
  - eac3
  - flac
  - g723_1
  - mlp
  - mp2
  - mp2fixed
  - nellymoser
  - opus
  - real_144
  - sbc
  - truehd
  - tta
  - vorbis
  - wavpack
  - wmav1
  - wmav2
  - pcm_alaw
  - pcm_bluray
  - pcm_dvd
  - pcm_f32be
  - pcm_f32le
  - pcm_f64be
  - pcm_f64le
  - pcm_mulaw
  - pcm_s8
  - pcm_s8_planar
  - pcm_s16be
  - pcm_s16be_planar
  - pcm_s16le
  - pcm_s16le_planar
  - pcm_s24be
  - pcm_s24daud
  - pcm_s24le
  - pcm_s24le_planar
  - pcm_s32be
  - pcm_s32le
  - pcm_s32le_planar
  - pcm_s64be
  - pcm_s64le
  - pcm_u8
  - pcm_u16be
  - pcm_u16le
  - pcm_u24be
  - pcm_u24le
  - pcm_u32be
  - pcm_u32le
  - pcm_vidc
  - roq_dpcm
  - adpcm_adx
  - adpcm_argo
  - g722
  - g726
  - g726le
  - adpcm_ima_amv
  - adpcm_ima_alp
  - adpcm_ima_apm
  - adpcm_ima_qt
  - adpcm_ima_ssi
  - adpcm_ima_wav
  - adpcm_ima_ws
  - adpcm_ms
  - adpcm_swf
  - adpcm_yamaha
  - libgsm
  - libgsm_ms
  - libmp3lame
  - libopencore_amrnb
  - libopus
  - libspeex
  - libvorbis
  - anull
...
---
video_codecs:
  - a64multi
  - a64multi5
  - alias_pix
  - amv
  - apng
  - asv1
  - asv2
  - avrp
  - avui
  - bitpacked
  - bmp
  - cfhd
  - cinepak
  - cljr
  - dnxhd
  - dpx
  - dvvideo
  - dxv
  - exr
  - ffv1
  - ffv1_vulkan
  - ffvhuff
  - fits
  - flashsv
  - flashsv2
  - flv
  - gif
  - h261
  - h263
  - h263p
  - hap
  - huffyuv
  - jpeg2000
  - jpegls
  - ljpeg
  - magicyuv
  - mjpeg
  - mpeg1video
  - mpeg2video
  - mpeg4
  - msmpeg4v2
  - msmpeg4
  - msrle
  - msvideo1
  - pam
  - pbm
  - pcx
  - pfm
  - pgm
  - pgmyuv
  - phm
  - png
  - ppm
  - prores
  - prores_aw
  - prores_ks
  - qoi
  - qtrle
  - r10k
  - r210
  - rawvideo
  - roqvideo
  - rpza
  - rv10
  - rv20
  - sgi
  - smc
  - snow
  - speedhq
  - sunrast
  - svq1
  - targa
  - tiff
  - utvideo
  - v210
  - v308
  - v408
  - v410
  - vbn
  - vc2
  - wbmp
  - wrapped_avframe
  - wmv1
  - wmv2
  - xbm
  - xface
  - xwd
  - y41p
  - yuv4
  - zlib
  - zmbv
  - hdr
  - libaom-av1
  - libjxl_anim
  - libjxl
  - libopenjpeg
  - librav1e
  - libsvtav1
  - libtheora
  - libvpx
  - libvpx-vp9
  - libwebp_anim
  - libwebp
  - libx264
  - libx264rgb
  - libx265
  - libxvid
  - h263_v4l2m2m
  - av1_nvenc
  - av1_qsv
  - av1_amf
  - av1_vaapi
  - av1_vulkan
  - h264_amf
  - h264_nvenc
  - h264_qsv
  - h264_v4l2m2m
  - h264_vaapi
  - h264_vulkan
  - hevc_amf
  - hevc_nvenc
  - hevc_qsv
  - hevc_v4l2m2m
  - hevc_vaapi
  - hevc_vulkan
  - mjpeg_qsv
  - mjpeg_vaapi
  - mpeg2_qsv
  - mpeg2_vaapi
  - mpeg4_v4l2m2m
  - vp8_v4l2m2m
  - vp8_vaapi
  - vp9_vaapi
  - vp9_qsv
  - vnull
...
[1]    3971902 segmentation fault (core dumped)  shotcut

[ddennedy]

You should try using one of our builds to see if it makes a difference.

[ddennedy]

Maybe related to #1731

[promitheas17j]

You should try using one of our builds to see if it makes a difference.

Alright, I'll give it a try and report back if it fixes or if its still present. Thanks for the quick reply.

[bjurd]

I'm having this issue currently with a fresh shotcut install. I drag in a 3(ish) hour long MKV file (1.8gb in size) and sometimes it will crash during playback (laggy stutters then death like OP said) and other times it will crash when dragging into the timelime (presumably during waveform generation).

System Info

$ pacman -Q shotcut
shotcut 25.10.31-1

$ fastfetch
                  -`                     adman@DESKTOP-XXXXXX
                 .o+`                    --------------------
                `ooo/                    OS: Arch Linux x86_64
               `+oooo:                   Host: MS-7E26 (1.0)
              `+oooooo:                  Kernel: Linux 6.17.8-arch1-1
              -+oooooo+:                 Uptime: 2 hours, 42 mins
            `/:-:++oooo+:                Packages: 1334 (pacman)
           `/++++/+++++++:               Shell: bash 5.3.3
          `/++++++++++++++:              Display (SAMSUNG): 3840x2160 @ 1.25x i]
         `/+++ooooooooooooo/`            DE: Xfce4 4.20
        ./ooosssso++osssssso+`           WM: Xfwm4 (X11)
       .oossssso-````/ossssss+`          WM Theme: Default
      -osssssso.      :ssssssso.         Theme: Adwaita [GTK2/3/4]
     :osssssss/        osssso+++.        Icons: elementary [GTK2/3/4]
    /ossssssss/        +ssssooo/-        Font: Sans (10pt) [GTK2/3/4]
  `/ossssso+/:-        -:/+osssso+-      Cursor: Adwaita (16px)
 `+sso+:-`                 `.-/+oso:     Terminal: xfce4-terminal 1.1.5
`++:.                           `-/+/    CPU: AMD Ryzen 7 7800X3D (16) @ 5.05 Gz
.`                                 `/    GPU: AMD Radeon RX 7800 XT [Discrete]
                                         Memory: 8.53 GiB / 62.41 GiB (14%)
                                         Swap: 16.00 KiB / 4.00 GiB (0%)
                                         Disk (/): 533.31 GiB / 1.79 TiB (29%) 4
                                         Disk (/mnt/externalkodi): 2.40 TiB / 3k
                                         Local IP (wg0-mullvad): 10.138.148.59/2
                                         Locale: en_US.UTF-8

I attached gdb and enabled QT logging and was gifted a massive log file: gdb-shotcut.log

[promitheas17j]

I'm having this issue currently with a fresh shotcut install. I drag in a 3(ish) hour long MKV file (1.8gb in size) and sometimes it will crash during playback (laggy stutters then death like OP said) and other times it will crash when dragging into the timelime (presumably during waveform generation).

System Info

$ pacman -Q shotcut
shotcut 25.10.31-1

$ fastfetch
                  -`                     adman@DESKTOP-XXXXXX
                 .o+`                    --------------------
                `ooo/                    OS: Arch Linux x86_64
               `+oooo:                   Host: MS-7E26 (1.0)
              `+oooooo:                  Kernel: Linux 6.17.8-arch1-1
              -+oooooo+:                 Uptime: 2 hours, 42 mins
            `/:-:++oooo+:                Packages: 1334 (pacman)
           `/++++/+++++++:               Shell: bash 5.3.3
          `/++++++++++++++:              Display (SAMSUNG): 3840x2160 @ 1.25x i]
         `/+++ooooooooooooo/`            DE: Xfce4 4.20
        ./ooosssso++osssssso+`           WM: Xfwm4 (X11)
       .oossssso-````/ossssss+`          WM Theme: Default
      -osssssso.      :ssssssso.         Theme: Adwaita [GTK2/3/4]
     :osssssss/        osssso+++.        Icons: elementary [GTK2/3/4]
    /ossssssss/        +ssssooo/-        Font: Sans (10pt) [GTK2/3/4]
  `/ossssso+/:-        -:/+osssso+-      Cursor: Adwaita (16px)
 `+sso+:-`                 `.-/+oso:     Terminal: xfce4-terminal 1.1.5
`++:.                           `-/+/    CPU: AMD Ryzen 7 7800X3D (16) @ 5.05 Gz
.`                                 `/    GPU: AMD Radeon RX 7800 XT [Discrete]
                                         Memory: 8.53 GiB / 62.41 GiB (14%)
                                         Swap: 16.00 KiB / 4.00 GiB (0%)
                                         Disk (/): 533.31 GiB / 1.79 TiB (29%) 4
                                         Disk (/mnt/externalkodi): 2.40 TiB / 3k
                                         Local IP (wg0-mullvad): 10.138.148.59/2
                                         Locale: en_US.UTF-8

I attached gdb and enabled QT logging and was gifted a massive log file: gdb-shotcut.log

Are you using an official build or the package from the AUR? Asking because I see you also use arch linux. If youre using the AUR version, could you try one of the official builds and report back your results? Ive been meaning to do it myself as well, but life (job applications, studying for job position tests, family stuff) hasn't given me the chance to try one of the official builds yet.

[ddennedy]

From the log's backtrace, here is the part that gets to Shotcut:

#25 QAbstractItemModel::dataChanged
    (this=this@entry=0x555556c0b480, _t1=..., _t2=..., _t3=...)
    at /usr/src/debug/qt6-base/build/src/corelib/Core_autogen/include/moc_qabstractitemmodel.cpp:658
#26 0x0000555555678216 in MultitrackModel::audioLevelsReady
    (this=<optimized out>, index=...)
    at /usr/src/debug/shotcut/shotcut/src/models/multitrackmodel.cpp:2611
        roles = {<QListSpecialMethods<int>> = {<QListSpecialMethodsBase<int>> = {<No data fields>}, <No data fields>}, d = {d = 0x55555a1d98e0, ptr = 0x55555a1d98f0, size = 1}}

Everything above that is in Qt. Basically, this is about when waveform data is done and being transferred into QML, which it uses for the timeline.

Try not adding it to the Playlist or Timeline. Trim it in the player before adding it to either of those to see if the problem is gone. Does it work OK with a similarly prepared file that is short?

I test my builds occasionally with long (1 - 2 hours) videos. I may not volunteer to test many hours and/or Arch's package. I just tested three 2+ hour movies placed on the timeline in today's daily build without issue. It is normal that playback is more choppy or UI is more laggy while it is generating waveforms in the background, and hours of video prolongs your exposure to that. Maybe you want to wait for that to complete.

[bjurd]

It is in fact an issue with the AUR package. Using the AppImage from Github works fine. Whoever maintains the AUR package must've messed something up.

EDIT: Actually NOT the AUR package, I got it from this