Recherche avancée

Sur d’autres sites (7611)

• avcodec/ac3enc : Avoid copying samples

  14 avril 2024, par Andreas Rheinhardt

  avcodec/ac3enc : Avoid copying samples
  Only the last 256 samples of each frame are used ;
  
  the encoder currently uses a buffer for 1536 + 256 samples
  
  whose first 256 samples contain are the last 256 samples
  
  from the last frame and the next 1536 are the samples
  
  of the current frame.
  
  Yet since 238b2d4155d9779d770fccb3594076bb32742c82 all the
  
  DSP functions only need 256 contiguous samples and this can
  
  be achieved by only retaining the last 256 samples of each
  
  frame. Doing so saves 6KiB per channel.
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
  

  • [DH] libavcodec/ac3enc.c
  • [DH] libavcodec/ac3enc.h
  • [DH] libavcodec/ac3enc_template.c

• FFMPEG Streaming Issue - "Connection Failed : I/O Error"

  25 avril 2023, par 1080Jake

  For a fun project I wanted to see if I could create an SRT stream from an active SDI input (1080i59.94) on a BMD Decklink Quad card. Whenever I try to execute my syntax, I get the following prompt "Connection to srt ://127.0.0.1:1234 failed : I/O error"
Is there anyway to use a debug mode and get more details about what is causing this ? I am very new to FFMPEG and obviously clueless. This is the syntax I am trying to execute -

  


  C:\Users\01>ffmpeg -f decklink -i "DeckLink Quad (8)" -c:v libx265 -preset ultrafast -b:v 5000k -f mpegts srt://127.0.0.1:1234


  


  Full printout here -

  


  C:\Users\01>ffmpeg -f decklink -i "DeckLink Quad (8)" -c:v libx265 -preset ultrafast -b:v 5000k -bufsize 3000k -f mpegts srt://127.0.0.1:1234
ffmpeg version n6.0-ffmpeg-windows-build-helpers Copyright (c) 2000-2023 the FFmpeg developers
  built with gcc 10.2.0 (GCC)
  configuration: --pkg-config=pkg-config --pkg-config-flags=--static --extra-version=ffmpeg-windows-build-helpers --enable-version3 --disable-debug --disable-w32threads --arch=x86_64 --target-os=mingw32 --cross-prefix=/home/runner/work/ffmpeg-stable-autobuild/ffmpeg-stable-autobuild/sandbox/cross_compilers/mingw-w64-x86_64/bin/x86_64-w64-mingw32- --enable-libcaca --enable-gray --enable-libtesseract --enable-fontconfig --enable-gmp --enable-libass --enable-libbluray --enable-libbs2b --enable-libflite --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopus --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvo-amrwbenc --enable-libvorbis --enable-libwebp --enable-libzimg --enable-libzvbi --enable-libmysofa --enable-libopenjpeg --enable-libopenh264 --enable-libvmaf --enable-libsrt --enable-libxml2 --enable-opengl --enable-libdav1d --enable-cuda-llvm --enable-gnutls --enable-libsvtav1 --enable-libvpx --enable-libaom --enable-nvenc --enable-nvdec --extra-libs=-lharfbuzz --extra-libs=-lm --extra-libs=-lshlwapi --extra-libs=-lmpg123 --extra-libs=-lpthread --extra-cflags=-DLIBTWOLAME_STATIC --extra-cflags=-DMODPLUG_STATIC --extra-cflags=-DCACA_STATIC --enable-amf --enable-libmfx --enable-gpl --enable-frei0r --enable-librubberband --enable-libvidstab --enable-libx264 --enable-libx265 --enable-avisynth --enable-libaribb24 --enable-libxvid --enable-libdavs2 --enable-libxavs2 --enable-libxavs --extra-cflags='-mtune=generic' --extra-cflags=-O3 --enable-static --disable-shared --prefix=/home/runner/work/ffmpeg-stable-autobuild/ffmpeg-stable-autobuild/sandbox/cross_compilers/mingw-w64-x86_64/x86_64-w64-mingw32 --enable-nonfree --enable-libfdk-aac --enable-decklink
  libavutil      58.  2.100 / 58.  2.100
  libavcodec     60.  3.100 / 60.  3.100
  libavformat    60.  3.100 / 60.  3.100
  libavdevice    60.  1.100 / 60.  1.100
  libavfilter     9.  3.100 /  9.  3.100
  libswscale      7.  1.100 /  7.  1.100
  libswresample   4. 10.100 /  4. 10.100
  libpostproc    57.  1.100 / 57.  1.100
[decklink @ 000002ad2785a6c0] Autodetected the input mode
[decklink @ 000002ad2785a6c0] Found Decklink mode 1920 x 1080 with rate 29.97(i)
Guessed Channel Layout for Input Stream #0.0 : stereo
Input #0, decklink, from 'DeckLink Quad (8)':
  Duration: N/A, start: 0.000000, bitrate: 995869 kb/s
  Stream #0:0: Audio: pcm_s16le, 48000 Hz, 2 channels, s16, 1536 kb/s
  Stream #0:1: Video: rawvideo (UYVY / 0x59565955), uyvy422(top first), 1920x1080, 994333 kb/s, 29.97 tbr, 1000k tbn
[srt @ 000002ad2a870dc0] Connection to srt://127.0.0.1:1234 failed: I/O error
srt://127.0.0.1:1234: I/O error


  


  Instead of using an SDI input from my BMD card, I also tried to use a local mp4 file on my PC but I get the same prompt. Note - I am running FFMPEG on a Windows 10 PC.

  


• encode 3 different mp4 video to a standard, then join them without encoding [closed]

  10 novembre 2023, par Joe Cook

  I've found many topics on this but none seem to work fully. when I encode them, they look like specs are equal, but when I join them they stutter and freeze.

  


  outputa.mp4 2304/1536    9.7 frame/rate   security camera no audio
outputb.mp4 1140/720   29.91 frame/rate   phone portrait
outputc.mp4 1920/1080  29.91 frame/rate   phone landscape


  


  padding looks good, and resolution is the same, joining stutters/freezes

  


  'ffmpeg\bin\ffmpeg -y -i outputc.mp4 -vf "[in]scale=iw*min(2304/iw\,1536/ih):ih*min(2304/iw\,1536/ih)[scaled]; [scaled]pad=2304:1536:(2304-iw*min(2304/iw\,1536/ih))/2:(1536-ih*min(2304/iw\,1536/ih))/2[padded]; [padded]setsar=1:1[out]" -c:v libx264 -c:a copy temp\output3.mp4'


  


  padding looks good, and resolution is the same, framerate same, joining stutters/freezes

  


  'ffmpeg\bin\ffmpeg -y -i output3.mp4 -vf "scale=2304:1536:force_original_aspect_ratio=decrease,pad=2304:1536:(ow-iw)/2:      (oh-ih)/2,setsar=1:1,fps=fps=30,settb=AVTB,setpts=PTS-STARTPTS" -vcodec libx264 -pix_fmt yuv420p outputc.mp4'


  


  when I join it stutters and freezes

  


  'ffmpeg -f concat -safe 0 -i list.txt -c:v copy -c:a copy output.mp4'