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Spitfire Parade - Crisis
15 mai 2011, par
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Wired NextMusic
14 mai 2011, par
Mis à jour : Février 2012
Langue : English
Type : Video
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14 mai 2011, par
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Langue : français
Type : Video
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13 mai 2011, par
Mis à jour : Février 2012
Langue : English
Type : Video
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Carte de Schillerkiez
13 mai 2011, par
Mis à jour : Septembre 2011
Langue : English
Type : Texte
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Publier une image simplement
13 avril 2011, par ,
Mis à jour : Février 2012
Langue : français
Type : Video
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avfilter : remove deprecated FF_API_LINK_PUBLIC
19 février, par James Almer -
Resizing AVIF images with transparency with FFmpeg [closed]
4 octobre 2024, par CalebmerI'm trying to resize an image with transparency with FFmpeg, however the output looks to only be a resized version of the alpha layer.


When I try to do a noop transform of the AVIF image with an alpha layer :


ffmpeg -i input.avif output.avif



output.avif
appears to be the alpha layer with black representing alpha 0 and white representing alpha 1.

ffprobe input.avif
gives me :

ffprobe version 7.0.2 Copyright (c) 2007-2024 the FFmpeg developers
 built with Apple clang version 15.0.0 (clang-1500.3.9.4)
 configuration: --prefix=/opt/homebrew/Cellar/ffmpeg/7.0.2 --enable-shared --enable-pthreads --enable-version3 --cc=clang --host-cflags= --host-ldflags='-Wl,-ld_classic' --enable-ffplay --enable-gnutls --enable-gpl --enable-libaom --enable-libaribb24 --enable-libbluray --enable-libdav1d --enable-libharfbuzz --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librav1e --enable-librist --enable-librubberband --enable-libsnappy --enable-libsrt --enable-libssh --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 --enable-audiotoolbox --enable-neon
 libavutil 59. 8.100 / 59. 8.100
 libavcodec 61. 3.100 / 61. 3.100
 libavformat 61. 1.100 / 61. 1.100
 libavdevice 61. 1.100 / 61. 1.100
 libavfilter 10. 1.100 / 10. 1.100
 libswscale 8. 1.100 / 8. 1.100
 libswresample 5. 1.100 / 5. 1.100
 libpostproc 58. 1.100 / 58. 1.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'input.avif':
 Metadata:
 major_brand : avif
 minor_version : 0
 compatible_brands: avifmif1miaf
 Duration: N/A, start: 0.000000, bitrate: N/A
 Stream #0:0[0x1]: Video: av1 (libdav1d) (Main) (av01 / 0x31307661), gray(pc), 336x252 [SAR 1:1 DAR 4:3], 1 fps, 1 tbr, 1 tbn (default)
 Stream #0:1[0x2]: Video: av1 (libdav1d) (High) (av01 / 0x31307661), yuv444p(pc, smpte170m/bt709/iec61966-2-1), 336x252 [SAR 1:1 DAR 4:3], 1 fps, 1 tbr, 1 tbn



Seeing there are two streams (the first stream being
gray(pc)
, probably the alpha layer) I next tried :

ffmpeg -i input.avif -map 0:v:1 output.avif



To see the second stream and it gave me the image without any alpha channel. Transparent pixels were black.


Ultimately I want to resize the AVIF file with
ffmpeg -i input.avif -vf "scale=iw/2:-1" output.avif
but that appears to only resize the greyscale alpha channel. Furthermore, this will be part of a script that operates on some AVIF files without an alpha channel and some AVIF files with an alpha channel and I don't know which files have an alpha channel ahead of time.ffmpeg -i input.avif -vf "scale=iw/2:-1" output.avif
works for files without an alpha channel.

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How can I remove silence of a video ? [closed]
23 septembre 2024, par AlexI wanted to automatically remove the silence from some of my videos.


I found the following command by searching :


ffmpeg -i C:\Users\`*`myusername`*`\Desktop\videowithsielence.mp4 -af silenceremove=1:0:-50dB C:\Users\`*`myusername`*`\Desktop\newvideo.mp4



There isn't any error and this is the following output :


ffmpeg version N-117094-g2bf588f273-20240921 Copyright (c) 2000-2024 the FFmpeg developers
 built with gcc 14.2.0 (crosstool-NG 1.26.0.106_ed12fa6)
 configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-w64-mingw32- --arch=x86_64 --target-os=mingw32 --enable-gpl --enable-version3 --disable-debug --disable-w32threads --enable-pthreads --enable-iconv --enable-zlib --enable-libfreetype --enable-libfribidi --enable-gmp --enable-libxml2 --enable-lzma --enable-fontconfig --enable-libharfbuzz --enable-libvorbis --enable-opencl --disable-libpulse --enable-libvmaf --disable-libxcb --disable-xlib --enable-amf --enable-libaom --enable-libaribb24 --enable-avisynth --enable-chromaprint --enable-libdav1d --enable-libdavs2 --enable-libdvdread --enable-libdvdnav --disable-libfdk-aac --enable-ffnvcodec --enable-cuda-llvm --enable-frei0r --enable-libgme --enable-libkvazaar --enable-libaribcaption --enable-libass --enable-libbluray --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librist --enable-libssh --enable-libtheora --enable-libvpx --enable-libwebp --enable-libzmq --enable-lv2 --enable-libvpl --enable-openal --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopenmpt --enable-librav1e --enable-librubberband --enable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libsvtav1 --enable-libtwolame --enable-libuavs3d --disable-libdrm --enable-vaapi --enable-libvidstab --enable-vulkan --enable-libshaderc --enable-libplacebo --enable-libvvenc --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libzimg --enable-libzvbi --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-libs=-lgomp --extra-ldflags=-pthread --extra-ldexeflags= --cc=x86_64-w64-mingw32-gcc --cxx=x86_64-w64-mingw32-g++ --ar=x86_64-w64-mingw32-gcc-ar --ranlib=x86_64-w64-mingw32-gcc-ranlib --nm=x86_64-w64-mingw32-gcc-nm --extra-version=20240921
 libavutil 59. 37.100 / 59. 37.100
 libavcodec 61. 17.100 / 61. 17.100
 libavformat 61. 6.100 / 61. 6.100
 libavdevice 61. 2.101 / 61. 2.101
 libavfilter 10. 3.100 / 10. 3.100
 libswscale 8. 2.100 / 8. 2.100
 libswresample 5. 2.100 / 5. 2.100
 libpostproc 58. 2.100 / 58. 2.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'C:\Users\*myusername*\Desktop\stille.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 encoder : Lavf61.1.100
 Duration: 00:00:17.60, start: 0.000000, bitrate: 14994 kb/s
 Stream #0:0[0x1](und): Video: h264 (Constrained Baseline) (avc1 / 0x31637661), yuv420p(tv, bt709, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 14915 kb/s, 60 fps, 60 tbr, 15360 tbn (default)
 Metadata:
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
 Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 83 kb/s (default)
 Metadata:
 handler_name : SoundHandler
 vendor_id : [0][0][0][0]
Stream mapping:
 Stream #0:0 -> #0:0 (h264 (native) -> h264 (libx264))
 Stream #0:1 -> #0:1 (aac (native) -> aac (native))
Press [q] to stop, [?] for help
[libx264 @ 000002b596997d00] using SAR=1/1
[libx264 @ 000002b596997d00] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX FMA3 BMI2 AVX2
[libx264 @ 000002b596997d00] profile High, level 4.2, 4:2:0, 8-bit
[libx264 @ 000002b596997d00] 264 - core 164 - H.264/MPEG-4 AVC codec - Copyleft 2003-2024 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deblock=1:0:0 analyse=0x3:0x113 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 me_range=16 chroma_me=1 trellis=1 8x8dct=1 cqm=0 deadzone=21,11 fast_pskip=1 chroma_qp_offset=-2 threads=18 lookahead_threads=3 sliced_threads=0 nr=0 decimate=1 interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1 b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scenecut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=23.0 qcomp=0.60 qpmin=0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
Output #0, mp4, to 'C:\Users\*myusername*\Desktop\Aufzeich.mp4':
 Metadata:
 major_brand : isom
 minor_version : 512
 compatible_brands: isomiso2avc1mp41
 encoder : Lavf61.6.100
 Stream #0:0(und): Video: h264 (avc1 / 0x31637661), yuv420p(tv, bt709, progressive), 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 60 fps, 15360 tbn (default)
 Metadata:
 handler_name : VideoHandler
 vendor_id : [0][0][0][0]
 encoder : Lavc61.17.100 libx264
 Side data:
 cpb: bitrate max/min/avg: 0/0/0 buffer size: 0 vbv_delay: N/A
 Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 128 kb/s (default)
 Metadata:
 handler_name : SoundHandler
 vendor_id : [0][0][0][0]
 encoder : Lavc61.17.100 aac
[out#0/mp4 @ 000002b594b08800] video:2969KiB audio:180KiB subtitle:0KiB other streams:0KiB global headers:0KiB muxing overhead: 0.825545%
frame= 1055 fps=236 q=-1.0 Lsize= 3174KiB time=00:00:16.54 bitrate=1571.3kbits/s speed= 3.7x
[libx264 @ 000002b596997d00] frame I:5 Avg QP:14.66 size:136185
[libx264 @ 000002b596997d00] frame P:351 Avg QP:18.48 size: 6338
[libx264 @ 000002b596997d00] frame B:699 Avg QP:25.92 size: 191
[libx264 @ 000002b596997d00] consecutive B-frames: 1.5% 6.1% 73.1% 19.3%
[libx264 @ 000002b596997d00] mb I I16..4: 61.0% 21.9% 17.2%
[libx264 @ 000002b596997d00] mb P I16..4: 0.2% 0.1% 0.0% P16..4: 4.8% 0.8% 0.8% 0.0% 0.0% skip:93.4%
[libx264 @ 000002b596997d00] mb B I16..4: 0.0% 0.0% 0.0% B16..8: 2.0% 0.0% 0.0% direct: 0.0% skip:98.0% L0:75.0% L1:22.4% BI: 2.5%
[libx264 @ 000002b596997d00] 8x8 transform intra:22.8% inter:38.2%
[libx264 @ 000002b596997d00] coded y,uvDC,uvAC intra: 57.3% 73.0% 56.4% inter: 1.0% 1.0% 0.1%
[libx264 @ 000002b596997d00] i16 v,h,dc,p: 31% 25% 32% 12%
[libx264 @ 000002b596997d00] i8 v,h,dc,ddl,ddr,vr,hd,vl,hu: 24% 21% 42% 2% 2% 2% 2% 3% 3%
[libx264 @ 000002b596997d00] i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 33% 31% 22% 2% 2% 2% 2% 2% 3%
[libx264 @ 000002b596997d00] i8c dc,h,v,p: 41% 32% 13% 13%
[libx264 @ 000002b596997d00] Weighted P-Frames: Y:0.3% UV:0.0%
[libx264 @ 000002b596997d00] ref P L0: 68.2% 7.2% 20.4% 4.2% 0.0%
[libx264 @ 000002b596997d00] ref B L0: 79.0% 18.8% 2.2%
[libx264 @ 000002b596997d00] ref B L1: 98.4% 1.6%
[libx264 @ 000002b596997d00] kb/s:1382.74
[aac @ 000002b596a4f680] Qavg: 21440.516



But the new video is exactly the same as the first one. I also tried changing the 50dB number but that didn't work either... My question is "Why ?" and "How can I fix this ?"...