[FFmpeg-trac] #10272(ffmpeg:new): FFMpeg repots error for non-monotonic dts but prints a true assertion.

[FFmpeg]

#10272: FFMpeg repots error for non-monotonic dts but prints a true assertion.
-------------------------------------+----------------------------------
             Reporter:  ethanpet113  |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  ffmpeg       |                  Version:  5.1.2
             Keywords:               |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+----------------------------------
 Summary of the bug:
 I am trying to scan files for anomalies by looking at the output of
 ffmpeg.  Normally I set the verbosity to errors only, but for the benefit
 of the reader I have included the normal output.

 Here is an example of an "error" I am getting:
 **[null @ 0x7fe0d1708880] Application provided invalid, non monotonically
 increasing dts to muxer in stream 1: 7776000 >= 7776000**

 FFMpeg in certain cases will report that dts is non monotonic.
 When it does this it will also assert that x>=x.

 Since it is indeed true that **x>=x** it should not be printing this.  It
 should be searching for **y>=x** but must be looking for **y>x**.
 That or the error message is incorrect and should read **x>x**.  I don't
 know if this value needs to be strictly monotonic or not, and it seems
 neither did whoever wrote this step.


 {{{
 $ffmpeg -i file.mov -codec copy -f null -

 ffmpeg version 5.1.2 Copyright (c) 2000-2022 the FFmpeg developers
   built with Apple clang version 14.0.0 (clang-1400.0.29.202)
   configuration: --prefix=/usr/local/Cellar/ffmpeg/5.1.2_6 --enable-shared
 --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-
 ldflags= --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom
 --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-
 libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-
 librubberband --enable-libsnappy --enable-libsrt --enable-libsvtav1
 --enable-libtesseract --enable-libtheora --enable-libvidstab --enable-
 libvmaf --enable-libvorbis --enable-libvpx --enable-libwebp --enable-
 libx264 --enable-libx265 --enable-libxml2 --enable-libxvid --enable-lzma
 --enable-libfontconfig --enable-libfreetype --enable-frei0r --enable-
 libass --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-
 libopenjpeg --enable-libspeex --enable-libsoxr --enable-libzmq --enable-
 libzimg --disable-libjack --disable-indev=jack --enable-videotoolbox
   libavutil      57. 28.100 / 57. 28.100
   libavcodec     59. 37.100 / 59. 37.100
   libavformat    59. 27.100 / 59. 27.100
   libavdevice    59.  7.100 / 59.  7.100
   libavfilter     8. 44.100 /  8. 44.100
   libswscale      6.  7.100 /  6.  7.100
   libswresample   4.  7.100 /  4.  7.100
   libpostproc    56.  6.100 / 56.  6.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'file.mov':
   Metadata:
     creation_time   : 2005-04-30T15:05:08.000000Z
   Duration: 00:04:03.01, start: 0.000000, bitrate: 259 kb/s
   Stream #0:0[0x1](eng): Audio: qdm2 (QDM2 / 0x324D4451), 32000 Hz, mono,
 s16, 32 kb/s (default)
     Metadata:
       creation_time   : 2005-04-30T15:05:08.000000Z
       handler_name    : Apple Sound Media Handler
       vendor_id       : QDes
   Stream #0:1[0x2](eng): Video: svq3 (SVQ3 / 0x33515653), yuvj420p(pc),
 320x240, 225 kb/s, 29.22 fps, 29.97 tbr, 30k tbn (default)
     Metadata:
       creation_time   : 2005-04-30T15:05:08.000000Z
       handler_name    : Apple Video Media Handler
       vendor_id       : SMI
       encoder         : Sorenson Video 3
 Output #0, null, to 'pipe:':
   Metadata:
     encoder         : Lavf59.27.100
   Stream #0:0(eng): Video: svq3 (SVQ3 / 0x33515653), yuvj420p(pc),
 320x240, q=2-31, 225 kb/s, 29.22 fps, 29.97 tbr, 30k tbn (default)
     Metadata:
       creation_time   : 2005-04-30T15:05:08.000000Z
       handler_name    : Apple Video Media Handler
       vendor_id       : SMI
       encoder         : Sorenson Video 3
   Stream #0:1(eng): Audio: qdm2 (QDM2 / 0x324D4451), 32000 Hz, mono, s16,
 32 kb/s (default)
     Metadata:
       creation_time   : 2005-04-30T15:05:08.000000Z
       handler_name    : Apple Sound Media Handler
       vendor_id       : QDes
 Stream mapping:
   Stream #0:1 -> #0:0 (copy)
   Stream #0:0 -> #0:1 (copy)
 Press [q] to stop, [?] for help
 [null @ 0x7fe0d1708880] Application provided invalid, non monotonically
 increasing dts to muxer in stream 1: 7776000 >= 7776000
     Last message repeated 7 times
 frame= 7102 fps=0.0 q=-1.0 Lsize=N/A time=00:04:03.00 bitrate=N/A
 speed=1.46e+04x
 video:6700kB audio:954kB subtitle:0kB other streams:0kB global headers:0kB
 muxing overhead: unknown

 }}}

 In general playback seems fine as this just occurs at the end of stream
 for some streams written by weird encoders.
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/10272>
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