[FFmpeg-trac] #5910(undetermined:new): AAC to PCM conversion inserts extra silence in the beginning
FFmpeg
trac at avcodec.org
Thu Oct 27 12:03:08 EEST 2016
#5910: AAC to PCM conversion inserts extra silence in the beginning
-------------------------------------+-------------------------------------
Reporter: | Owner:
jwilhelmsson | Status: new
Type: defect | Component:
Priority: normal | undetermined
Version: unspecified | Resolution:
Keywords: aac pcm | Blocked By:
Blocking: | Reproduced by developer: 0
Analyzed by developer: 0 |
-------------------------------------+-------------------------------------
Comment (by jwilhelmsson):
It seems so, yes. I asked our server guy to install the latest, and all
files convert exactly the same way. Here's the output for the seven second
movie clip:
{{{
ffmpeg -i g_7s.aac -c:a pcm_s24le -ar 48k g_7s_ffmpeg.wav
ffmpeg version N-82143-gbf14393 Copyright (c) 2000-2016 the FFmpeg
developers
built with gcc 4.7.3 (Gentoo 4.7.3-r1 p1.4, pie-0.5.5)
configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64
--docdir=/usr/share/doc/ffmpeg-9999/html --mandir=/usr/share/man --enable-
shared --cc=x86_64-pc-linux-gnu-gcc --cxx=x86_64-pc-linux-gnu-g++
--ar=x86_64-pc-linux-gnu-ar --optflags='-march=core2 -mtune=generic -O2
-pipe' --disable-static --enable-avfilter --enable-avresample --disable-
stripping --disable-indev=v4l2 --disable-outdev=v4l2 --disable-indev=alsa
--disable-indev=oss --disable-indev=jack --disable-outdev=alsa --disable-
outdev=oss --disable-outdev=sdl --enable-version3 --enable-nonfree
--enable-bzlib --disable-runtime-cpudetect --disable-debug --disable-
gcrypt --disable-gnutls --disable-gmp --enable-gpl --enable-hardcoded-
tables --enable-iconv --disable-lzma --enable-network --disable-openssl
--enable-postproc --disable-libsmbclient --disable-ffplay --disable-sdl2
--disable-vaapi --disable-vdpau --disable-xlib --disable-libxcb --disable-
libxcb-shm --disable-libxcb-xfixes --enable-zlib --disable-libcdio
--disable-libiec61883 --disable-libdc1394 --disable-libcaca --disable-
openal --disable-opengl --disable-libv4l2 --disable-libpulse --enable-
libopencore-amrwb --enable-libopencore-amrnb --enable-libfdk-aac --enable-
libopenjpeg --disable-libbluray --disable-libcelt --disable-libgme
--enable-libgsm --disable-mmal --disable-libmodplug --disable-libopus
--disable-libilbc --disable-librtmp --disable-libssh --enable-
libschroedinger --enable-libspeex --enable-libvorbis --disable-libvpx
--disable-libzvbi --disable-libbs2b --disable-chromaprint --disable-
libebur128 --disable-libflite --disable-frei0r --disable-libfribidi
--disable-fontconfig --disable-ladspa --enable-libass --enable-libfreetype
--disable-librubberband --disable-libzimg --disable-libsoxr --enable-
pthreads --disable-libvo-amrwbenc --enable-libmp3lame --disable-libkvazaar
--disable-nvenc --disable-libopenh264 --disable-libsnappy --enable-
libtheora --disable-libtwolame --disable-libwavpack --disable-libwebp
--enable-libx264 --disable-libx265 --enable-libxvid --disable-x11grab
--disable-amd3dnow --disable-amd3dnowext --disable-aesni --disable-avx
--disable-avx2 --disable-fma3 --disable-fma4 --disable-sse3 --disable-
ssse3 --disable-sse4 --disable-sse42 --disable-xop --cpu=core2 --disable-
doc --disable-htmlpages --enable-manpages
libavutil 55. 35.100 / 55. 35.100
libavcodec 57. 65.100 / 57. 65.100
libavformat 57. 57.100 / 57. 57.100
libavdevice 57. 2.100 / 57. 2.100
libavfilter 6. 66.100 / 6. 66.100
libavresample 3. 2. 0 / 3. 2. 0
libswscale 4. 3.100 / 4. 3.100
libswresample 2. 4.100 / 2. 4.100
libpostproc 54. 2.100 / 54. 2.100
[aac @ 0x88b2b0] Estimating duration from bitrate, this may be inaccurate
Input #0, aac, from 'g_7s.aac':
Duration: 00:00:07.01, bitrate: 320 kb/s
Stream #0:0: Audio: aac (LC), 48000 Hz, stereo, fltp, 320 kb/s
Output #0, wav, to 'g_7s_ffmpeg.wav':
Metadata:
ISFT : Lavf57.57.100
Stream #0:0: Audio: pcm_s24le ([1][0][0][0] / 0x0001), 48000 Hz,
stereo, s32, 2304 kb/s
Metadata:
encoder : Lavc57.65.100 pcm_s24le
Stream mapping:
Stream #0:0 -> #0:0 (aac (native) -> pcm_s24le (native))
Press [q] to stop, [?] for help
size= 1974kB time=00:00:07.01 bitrate=2304.1kbits/s speed= 297x
video:0kB audio:1974kB subtitle:0kB other streams:0kB global headers:0kB
muxing overhead: 0.005046%
}}}
--
Ticket URL: <https://trac.ffmpeg.org/ticket/5910#comment:7>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker
More information about the FFmpeg-trac
mailing list