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• Overthinking My Search Engine Problem

  31 décembre 2013, par Multimedia Mike — General

  I wrote a search engine for my Game Music Appreciation website, because the site would have been significantly less valuable without it (and I would eventually realize that the search feature is probably the most valuable part of this endeavor). I came up with a search solution that was a bit sketchy, but worked… until it didn’t. I thought of a fix but still searched for more robust and modern solutions (where ‘modern’ is defined as something that doesn’t require compiling a C program into a static CGI script and hoping that it works on a server I can’t debug on).

  Finally, I realized that I was overthinking the problem– did you know that a bunch of relational database management systems (RDBMSs) support full text search (FTS) ? Okay, maybe you did, but I didn’t know this.

  Problem Statement
  My goal is to enable users to search the metadata (title, composer, copyright, other tags) attached to various games. To do this, I want to index a series of contrived documents that describe the metadata. 2 examples of these contrived documents, interesting because both of these games have very different titles depending on region, something the search engine needs to account for :

  system : Nintendo NES
  game : Snoopy’s Silly Sports Spectacular
  author : None ; copyright : 1988 Kemco ; dumped by : None
  additional tags : Donald Duck.nsf Donald Duck
  system : Super Nintendo
  
  game : Arcana
  
  author : Jun Ishikawa, Hirokazu Ando ; copyright : 1992 HAL Laboratory ; dumped by : Datschge
  
  additional tags : card.rsn.gamemusic Card Master Cardmaster
  

  The index needs to map these documents to various pieces of game music and the search solution needs to efficiently search these documents and find the various game music entries that match a user’s request.

  Now that I’ve been looking at it for long enough, I’m able to express the problem surprisingly succinctly. If I had understood that much originally, this probably would have been simpler.

  First Solution & Breakage
  My original solution was based on SWISH-E. The CGI script was a C program that statically linked the SWISH-E library into a binary that miraculously ran on my web provider. At least, it ran until it decided to stop working a month ago when I added a new feature unrelated to search. It was a very bizarre problem, the details of which would probably bore you to tears. But if you care, the details are all there in the Stack Overflow question I asked on the matter.

  While no one could think of a direct answer to the problem, I eventually thought of a roundabout fix. The problem seemed to pertain to the static linking. Since I couldn’t count on the relevant SWISH-E library to be on my host’s system, I uploaded the shared library to the same directory as the CGI script and used dlopen()/dlsym() to fetch the functions I needed. It worked again, but I didn’t know for how long.

  Searching For A Hosted Solution
  I know that anything is possible in this day and age ; while my web host is fairly limited, there are lots of solutions for things like this and you can deploy any technology you want, and for reasonable prices. I figured that there must be a hosted solution out there.

  I have long wanted a compelling reason to really dive into Amazon Web Services (AWS) and this sounded like a good opportunity. After all, my script works well enough ; if I could just find a simple Linux box out there where I could install the SWISH-E library and compile the CGI script, I should be good to go. AWS has a free tier and I started investigating this approach. But it seems like a rabbit hole with a lot of moving pieces necessary for such a simple task.

  I had heard that AWS had something in this area. Sure enough, it’s called CloudSearch. However, I’m somewhat discouraged by the fact that it would cost me around $75 per month to run the smallest type of search instance which is at the core of the service.

  Finally, I came to another platform called Heroku. It’s supposed to be super-scalable while having a free tier for hobbyists. I started investigating FTS on Heroku and found this article which recommends using the FTS capabilities of their standard hosted PostgreSQL solution. However, the free tier of Postgres hosting only allows for 10,000 rows of data. Right now, my database has about 5400 rows. I expect it to easily overflow the 10,000 limit as soon as I incorporate the C64 SID music corpus.

  However, this Postgres approach planted a seed.

  RDBMS Revelation
  I have 2 RDBMSs available on my hosting plan– MySQL and SQLite (the former is a separate service while SQLite is built into PHP). I quickly learned that both have FTS capabilities. Since I like using SQLite so much, I elected to leverage its FTS functionality. And it’s just this simple :

  CREATE VIRTUAL TABLE gamemusic_metadata_fts USING fts3
  ( content TEXT, game_id INT, title TEXT ) ;
  SELECT id, title FROM gamemusic_metadata_fts WHERE content MATCH "arcana" ;
  
  479|Arcana
  

  The ‘content’ column gets the metadata pseudo-documents. The SQL gets wrapped up in a little PHP so that it queries this small database and turns the result into JSON. The script is then ready as a drop-in replacement for the previous script.

• FFMPEG NVENC encoding with Windows10

  1er mars 2021, par Daniel Bartley

  I had to reinstall windows 10 because windows. I have this exact same code working prior to the reinstall, however after I cant get it to work.

  



  I am using the latest nvidia drivers 416.16
I have VisualStudio and Cuda Toolkit installed
2x 1080TIs

  



  Using ffmpeg 4.0.2 :

  



  T:\ffmpeg\bin\4.0.2\ffmpeg.exe -c:v h264_cuvid -i "T:\Streams\01-ready\2018-10-10 21-19-21.mp4" -i "T:\Streams\10-source\kpg-logo.png" -filter_complex "overlay=10:10" -b:v 24000k -c:v h264_nvenc -c:a copy "T:\Streams\02-encoded\2018-10-10 21-19-21_watermarked.mp4"


  



  Output :

  



  ffmpeg version 4.0.2 Copyright (c) 2000-2018 the FFmpeg developers
  built with gcc 7.3.1 (GCC) 20180722
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  libavutil      56. 14.100 / 56. 14.100
  libavcodec     58. 18.100 / 58. 18.100
  libavformat    58. 12.100 / 58. 12.100
  libavdevice    58.  3.100 / 58.  3.100
  libavfilter     7. 16.100 /  7. 16.100
  libswscale      5.  1.100 /  5.  1.100
  libswresample   3.  1.100 /  3.  1.100
  libpostproc    55.  1.100 / 55.  1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'T:\Streams\01-ready\2018-10-10 21-19-21.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.84.100
  Duration: 00:28:41.71, start: 0.000000, bitrate: 24422 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt470bg/unknown/unknown), 2560x1440, 24130 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 286 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Input #1, png_pipe, from 'T:\Streams\10-source\kpg-logo.png':
  Duration: N/A, bitrate: N/A
    Stream #1:0: Video: png, rgba(pc), 2560x1440 [SAR 2834:2834 DAR 16:9], 25 tbr, 25 tbn, 25 tbc
Stream mapping:
  Stream #0:0 (h264_cuvid) -> overlay:main
  Stream #1:0 (png) -> overlay:overlay
  overlay -> Stream #0:0 (h264_nvenc)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[h264_nvenc @ 000002851a001940] CreateInputBuffer failed: out of memory (10)
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
Conversion failed!
Press any key to continue . . .


  



  Error Message

  



   [h264_nvenc @ 000002851a001940] CreateInputBuffer failed: out of memory (10)
Error initializing output stream 0:0 -- Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height
Conversion failed!
Press any key to continue . . .


  



  Any ideas ?

  



  EDIT :
Still having issues, now even with the simple commands :

  



  ffmpeg.exe -y -hwaccel cuvid -c:v h264_cuvid -i "input" -c:v h264_nvenc -preset slow "output.mp4"
ffmpeg version 4.0.2 Copyright (c) 2000-2018 the FFmpeg developers
  built with gcc 7.3.1 (GCC) 20180722
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-bzlib --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth
  libavutil      56. 14.100 / 56. 14.100
  libavcodec     58. 18.100 / 58. 18.100
  libavformat    58. 12.100 / 58. 12.100
  libavdevice    58.  3.100 / 58.  3.100
  libavfilter     7. 16.100 /  7. 16.100
  libswscale      5.  1.100 /  5.  1.100
  libswresample   3.  1.100 /  3.  1.100
  libpostproc    55.  1.100 / 55.  1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'T:\Streams\01-ready\2018-10-15 20-49-44.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf57.84.100
  Duration: 00:00:10.64, start: 0.000000, bitrate: 22978 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709/unknown/unknown), 2560x1440, 24216 kb/s, 60 fps, 60 tbr, 15360 tbn, 120 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 156 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (h264 (h264_cuvid) -> h264 (h264_nvenc))
  Stream #0:1 -> #0:1 (aac (native) -> aac (native))
Press [q] to stop, [?] for help
Output #0, mp4, to 'T:\Streams\02-encoded\2018-10-15 20-49-44.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.12.100
    Stream #0:0(und): Video: h264 (h264_nvenc) (Main) (avc1 / 0x31637661), cuda, 2560x1440 [SAR 1:1 DAR 16:9], q=-1--1, 2000 kb/s, 60 fps, 15360 tbn, 60 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      encoder         : Lavc58.18.100 h264_nvenc
    Side data:
      cpb: bitrate max/min/avg: 0/0/2000000 buffer size: 4000000 vbv_delay: -1
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      encoder         : Lavc58.18.100 aac
[h264_cuvid @ 000001a99033b600] ctx->cvdl->cuvidMapVideoFrame(ctx->cudecoder, parsed_frame.dispinfo.picture_index, &mapped_frame, &pitch, &params) failed -> CUDA_ERROR_UNKNOWN: unknown error
Error while decoding stream #0:0: Generic error in an external library
/* repeated many many times */
[h264_nvenc @ 000001a98fcfc100] Failed locking bitstream buffer: invalid param (8)
video encoding failed: Invalid argument
[aac @ 000001a98fdcd380] Qavg: 64894.355
[aac @ 000001a98fdcd380] 2 frames left in the queue on closing
Conversion failed!
Press any key to continue . . .


  



  Full windows batch file :

  



  @echo off

set ffmpegversion=20181015-c27c7b4-win64-static

set sourcedir=T:\Streams\01-ready
set outputdir=T:\Streams\02-encoded
set finaldir=T:\ffmpeg\mp4-upload

set libdir=T:\ffmpeg\bin\%ffmpegversion%

set introvid=T:\Streams\10-source\kpg-intro-10pec-audio.mp4
set watermark=T:\Streams\10-source\kpg-logo.png
set introvidlen=3.00
set outputbitrate=24000

cd /d %libdir%

if not exist %outputdir% (
    mkdir %outputdir%
)

if not exist %finaldir% (
    mkdir %finaldir%
)

setlocal enabledelayedexpansion
@echo Checking %sourcedir%\*.mp4
for %%f in (%sourcedir%\*.mp4) do ( 
    if not exist "%outputdir%\%%~nf_watermarked.mp4" (
        %libdir%\ffmpeg.exe -i "%%f" -i "%watermark%" -filter_complex "overlay=0:0" -b:v %outputbitrate%k -s 2560x1440 -pix_fmt yuv420p -c:a copy "%outputdir%\%%~nf_watermarked.mp4"
        TIMEOUT 2
    )

    if not exist "%outputdir%\%%~nf_watermarked_ready.mp4" (
        %libdir%\ffmpeg.exe -i "%introvid%" -i "%outputdir%\%%~nf_watermarked.mp4" -an -filter_complex " [0:v]trim=start=0:end=%introvidlen%,setpts=PTS-STARTPTS[firstclip]; [1:v]trim=start=1,setpts=PTS-STARTPTS[secondclip]; [0:v]trim=start=%introvidlen%,setpts=PTS-STARTPTS[fadeoutsrc]; [1:v]trim=start=0:end=1,setpts=PTS-STARTPTS[fadeinsrc]; [fadeinsrc]format=pix_fmts=yuva420p, fade=t=in:st=0:d=1:alpha=1[fadein]; [fadeoutsrc]format=pix_fmts=yuva420p, fade=t=out:st=0:d=1:alpha=1[fadeout]; [fadein]fifo[fadeinfifo]; [fadeout]fifo[fadeoutfifo];[fadeoutfifo][fadeinfifo]overlay[crossfade]; [firstclip][crossfade][secondclip]concat=n=3[output]; [0:a][1:a] acrossfade=d=1 [audio]" -map "[output]" -map "[audio]" -c:v libx264 -c:a aac -b:v %outputbitrate%k -ar 44100 -ab 96k -sn "%outputdir%\%%~nf_watermarked_ready.mp4"
        TIMEOUT 2
    )

    if not exist "%finaldir%\%%~nf.mp4" (
        COPY "%outputdir%\%%~nf_watermarked_ready.mp4" "%finaldir%\%%~nf.mp4"
        TIMEOUT 2
    )
)

PAUSE


  


• FFMPEG intermittent failures reading live RTMP stream

  22 janvier 2019, par stevendesu

  The Command

  I’m attempting to read a live RTMP stream and save the result to a file with the following command :

  ffmpeg -re -rtmp_live live -y -i "rtmp://<server>/<app>/<stream>" -c copy -f flv /tmp/dump.flv
  
  </stream></app></server>

  I run this command then after 10-15 seconds I kill the process and check /tmp/dump.flv. I’m trying to do this for stream diagnostic purposes (determine the encoding, bitrate, resolution, pixel format, and key frame interval of the live stream)

  This command works about 25-50% of the time. When it works FFMPEG takes about 5 seconds to connect to the stream, then it begins dumping data to disk. After I kill the process, I can find a couple of megabytes of video data in /tmp/dump.flv which can be probed using ffprobe.

  When the command fails, it goes into one of two failure states :

  Failure State 1

  stderr is flooded with a series of messages about "missing picture in access unit with size X", and the output file /tmp/dump.flv is created but contains 0 bytes

  ffmpeg version 3.4.4-1~16.04.york0 Copyright (c) 2000-2018 the FFmpeg developers
  
    built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.10) 20160609
  
    configuration: --prefix=/usr --extra-version='1~16.04.york0' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  
    libavutil      55. 78.100 / 55. 78.100
  
    libavcodec     57.107.100 / 57.107.100
  
    libavformat    57. 83.100 / 57. 83.100
  
    libavdevice    57. 10.100 / 57. 10.100
  
    libavfilter     6.107.100 /  6.107.100
  
    libavresample   3.  7.  0 /  3.  7.  0
  
    libswscale      4.  8.100 /  4.  8.100
  
    libswresample   2.  9.100 /  2.  9.100
  
    libpostproc    54.  7.100 / 54.  7.100
  
  [NULL @ 0x55b72d568920] pps_id 381 out of range
  
  [AVBSFContext @ 0x55b72d5692c0] Invalid NAL unit 0, skipping.
  
      Last message repeated 1 times
  
  [h264 @ 0x55b72d568920] Invalid NAL unit 0, skipping.
  
      Last message repeated 1 times
  
  [h264 @ 0x55b72d568920] no frame!
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2200
  
  [AVBSFContext @ 0x55b72d5692c0] Invalid NAL unit 0, skipping.
  
      Last message repeated 2 times
  
  [h264 @ 0x55b72d568920] Invalid NAL unit 0, skipping.
  
      Last message repeated 2 times
  
  [h264 @ 0x55b72d568920] no frame!
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 3171
  
  [AVBSFContext @ 0x55b72d5692c0] Invalid NAL unit 0, skipping.
  
  [h264 @ 0x55b72d568920] Invalid NAL unit 0, skipping.
  
  [h264 @ 0x55b72d568920] no frame!
  
  [NULL @ 0x55b72d568920] missing picture in access unit with size 80572
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 1560
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2608
  
  [h264 @ 0x55b72d568920] non-existing PPS 0 referenced
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2734
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2885
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 77739
  
  [h264 @ 0x55b72d568920] non-existing PPS 254 referenced
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 3360
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2804
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 3051
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 3067
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 77693
  
  [h264 @ 0x55b72d568920] non-existing PPS 0 referenced
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2421
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2779
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2442
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2678
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 76877
  
  [h264 @ 0x55b72d568920] sps_id 15 out of range
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 1342
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2412
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 2238
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 3550
  
  [h264 @ 0x55b72d568920] missing picture in access unit with size 3075
  
  ...
  
  (after hitting Ctrl+C:)
  
  Input #0, flv, from 'rtmp://<server>/<app>/<stream>':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf57.83.100
  
    Duration: 00:00:00.00, start: 5285.919000, bitrate: N/A
  
      Stream #0:0: Video: h264 (Constrained Baseline), yuv420p, 1920x1080, 2543 kb/s, 24 fps, 24 tbr, 1k tbn, 48 tbc
  
  Output #0, flv, to '/tmp/dump.flv':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf57.83.100
  
      Stream #0:0: Video: h264 (Constrained Baseline) ([7][0][0][0] / 0x0007), yuv420p, 1920x1080, q=2-31, 2543 kb/s, 24 fps, 24 tbr, 1k tbn, 1k tbc
  
  Stream mapping:
  
    Stream #0:0 -> #0:0 (copy)
  
  Press [q] to stop, [?] for help
  
  frame=    0 fps=0.0 q=-1.0 Lsize=       0kB time=00:00:00.00 bitrate=N/A speed=   0x
  
  video:0kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown
  
  Exiting normally, received signal 2.
  
  </stream></app></server>

  Failure State 2

  The message "No start code is found." is displayed and FFMPEG immediately terminates after less than a half-second. When this happens the file /tmp/dump.flv is not created.

  ffmpeg version 3.4.4-1~16.04.york0 Copyright (c) 2000-2018 the FFmpeg developers
  
    built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.10) 20160609
  
    configuration: --prefix=/usr --extra-version='1~16.04.york0' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  
    libavutil      55. 78.100 / 55. 78.100
  
    libavcodec     57.107.100 / 57.107.100
  
    libavformat    57. 83.100 / 57. 83.100
  
    libavdevice    57. 10.100 / 57. 10.100
  
    libavfilter     6.107.100 /  6.107.100
  
    libavresample   3.  7.  0 /  3.  7.  0
  
    libswscale      4.  8.100 /  4.  8.100
  
    libswresample   2.  9.100 /  2.  9.100
  
    libpostproc    54.  7.100 / 54.  7.100
  
  [NULL @ 0x56274b0be920] missing picture in access unit with size 3710
  
  [AVBSFContext @ 0x56274b0bf2c0] No start code is found.
  
  rtmp://<server>/<app>/<stream>: could not find codec parameters
  
  Input #0, flv, from 'rtmp://<server>/<app>/<stream>':
  
    Metadata:
  
      major_brand     : isom
  
      minor_version   : 512
  
      compatible_brands: isomiso2avc1mp41
  
      encoder         : Lavf57.83.100
  
    Duration: 00:00:00.00, start: 0.000000, bitrate: N/A
  
      Stream #0:0: Video: h264, none, 2543 kb/s, 24 fps, 1k tbn
  
  Output #0, flv, to '/tmp/dump.flv':
  
  Output file #0 does not contain any stream
  
  </stream></app></server></stream></app></server>

  What I’ve tried

  • Adding or removing -re to try and limit the input frame rate to the source frame rate
  • Adding or removing -rtmp_live live
  • Adding or removing -timeout 5 (or any other timeout value)
  • Using RTMP URL parameters (e.g. -i "rtmp://<server>/<app>/<stream> live=1 timeout=5"</stream></app></server>)

  Does anyone know why this command’s success is so intermittent or how I can get more consistent results ?

  Alternate Acceptable Solution

  The only reason I’m using ffmpeg to dump the stream to a temporary file at all is because I plan to perform multiple tests on the file (at least two at the moment — one to get the encoding, and another to get the key frame interval). By downloading the stream I reduce bandwidth usage and reduce runtime. However it’s perfectly acceptable to forego ffmpeg and just use ffprobe directly on the RTMP URL if this would help.

  Note that I did try this and I get the same two failure states with ffprobe