[FFmpeg-trac] #11469(ffmpeg:closed): ffmpeg_demux: readrate plays "catch up" if output is blocked, then later resumed

[FFmpeg]

#11469: ffmpeg_demux: readrate plays "catch up" if output is blocked, then later
resumed
-------------------------------------+-------------------------------------
             Reporter:  Wallboy      |                    Owner:  Gyan
                                     |  Doshi <ffmpeg@…>
                 Type:  defect       |                   Status:  closed
             Priority:  normal       |                Component:  ffmpeg
              Version:  git-master   |               Resolution:  fixed
             Keywords:  demuxer      |               Blocked By:
  readrate                           |
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
Comment (by jb_alvarado):

 @Gyan, this patch breaks `-re` and `-readrate 1`. When I use now
 `-readrate 1` or `-re` I get a speed around ~0.5. Here is a full output:


 {{{
 ./ffmpeg -re -i '/home/jb/Videos/Punkt Licht Trailer ASI HD FINAL.mp4' -f
 null -
 ffmpeg version N-118534-g6232f416b1 Copyright (c) 2000-2025 the FFmpeg
 developers
   built with gcc 14 (GCC)
   configuration: --prefix=/home/jb/dev/github/compile-ffmpeg-osx-
 linux/local --disable-debug --disable-shared --disable-doc --enable-gpl
 --enable-version3 --enable-runtime-cpudetect --enable-avfilter
   libavutil      59. 57.100 / 59. 57.100
   libavcodec     61. 33.102 / 61. 33.102
   libavformat    61.  9.107 / 61.  9.107
   libavdevice    61.  4.100 / 61.  4.100
   libavfilter    10.  9.100 / 10.  9.100
   libswscale      8. 13.100 /  8. 13.100
   libswresample   5.  4.100 /  5.  4.100
   libpostproc    58.  4.100 / 58.  4.100
 Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/jb/Videos/Punkt Licht
 Trailer ASI HD FINAL.mp4':
   Metadata:
     major_brand     : mp42
     minor_version   : 0
     compatible_brands: mp42mp41
     creation_time   : 2021-10-28T07:40:48.000000Z
   Duration: 00:01:19.08, start: 0.000000, bitrate: 21036 kb/s
   Stream #0:0[0x1](eng): Video: h264 (High) (avc1 / 0x31637661),
 yuv420p(tv, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 20691 kb/s, 25
 fps, 25 tbr, 25k tbn (default)
     Metadata:
       creation_time   : 2021-10-28T07:40:48.000000Z
       handler_name    : ?Mainconcept Video Media Handler
       vendor_id       : [0][0][0][0]
       encoder         : AVC Coding
   Stream #0:1[0x2](eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz,
 stereo, fltp, 317 kb/s (default)
     Metadata:
       creation_time   : 2021-10-28T07:40:48.000000Z
       handler_name    : #Mainconcept MP4 Sound Media Handler
       vendor_id       : [0][0][0][0]
 Stream mapping:
   Stream #0:0 -> #0:0 (h264 (native) -> wrapped_avframe (native))
   Stream #0:1 -> #0:1 (aac (native) -> pcm_s16le (native))
 Press [q] to stop, [?] for help
 Output #0, null, to 'pipe:':
   Metadata:
     major_brand     : mp42
     minor_version   : 0
     compatible_brands: mp42mp41
     encoder         : Lavf61.9.107
   Stream #0:0(eng): Video: wrapped_avframe, yuv420p(tv, progressive),
 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 25 fps, 25 tbn (default)
     Metadata:
       encoder         : Lavc61.33.102 wrapped_avframe
       creation_time   : 2021-10-28T07:40:48.000000Z
       handler_name    : ?Mainconcept Video Media Handler
       vendor_id       : [0][0][0][0]
   Stream #0:1(eng): Audio: pcm_s16le, 48000 Hz, stereo, s16, 1536 kb/s
 (default)
     Metadata:
       encoder         : Lavc61.33.102 pcm_s16le
       creation_time   : 2021-10-28T07:40:48.000000Z
       handler_name    : #Mainconcept MP4 Sound Media Handler
       vendor_id       : [0][0][0][0]
 [out#0/null @ 0x2e29a240] video:849KiB audio:14828KiB subtitle:0KiB other
 streams:0KiB global headers:0KiB muxing overhead: unknown
 frame= 1977 fps= 14 q=-0.0 Lsize=N/A time=00:01:19.08 bitrate=N/A
 speed=0.556x
 }}}
-- 
Ticket URL: <https://trac.ffmpeg.org/ticket/11469#comment:6>
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