May 2022 - FFmpeg-trac - lists.ffmpeg.org

#9750(avfilter:new): overlay filter alpha premultiplied performs brighter on transparent images
by FFmpeg 01 May '22

01 May '22

#9750: overlay filter alpha premultiplied performs brighter on transparent images ------------------------------------+-------------------------------------- Reporter: windowsair | Type: defect Status: new | Priority: normal Component: avfilter | Version: git-master Keywords: | Blocked By: Blocking: | Reproduced by developer: 0 Analyzed by developer: 0 | ------------------------------------+-------------------------------------- == Summary of the bug: I'm using ffmpeg's overlay filter with alpha premultiplied parameter. I noticed that when a completely transparent image was overlay to the background video, the output video was much brighter. In the following demo, I will use RGBA8888 format images for overlay. Its use of RGBA (255,255,255,255,0) indicates full transparency (aka completely transparent white), and the result demonstrates a very noticeable brightening (the expected result should be unchanged, since the image is completely transparent). ps: Using RGBA (0,0,0,0) (aka completely transparent black) also results in a brightened image. == How to reproduce: {{{ % ffmpeg.exe -loglevel debug -i a1.mp4 -i a1.png -filter_complex "[0:v][1:v]overlay=x=0:y=0:alpha=premultiplied[v]" -map "[v]" -c:v:0 libx264 -f mp4 output.mp4 }}} == ffmpeg output {{{ ffmpeg version n5.0.1-3-gb655beb025-20220425 Copyright (c) 2000-2022 the FFmpeg developers built with gcc 11.2.0 (crosstool-NG 1.24.0.533_681aaef) 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 --enable-shared --disable-static --disable-w32threads --enable-pthreads --enable-iconv --enable-libxml2 --enable-zlib --enable-libfreetype --enable-libfribidi --enable-gmp --enable-lzma --enable-fontconfig --enable-libvorbis --enable-opencl --disable-libpulse --enable-libvmaf --disable-libxcb --disable-xlib --enable-amf --enable-libaom --enable- avisynth --enable-libdav1d --enable-libdavs2 --disable-libfdk-aac --enable-ffnvcodec --enable-cuda-llvm --enable-frei0r --enable-libgme --enable-libass --enable-libbluray --enable-libmp3lame --enable-libopus --enable-librist --enable-libtheora --enable-libvpx --enable-libwebp --enable-lv2 --enable-libmfx --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 --disable-vaapi --enable-libvidstab --enable-vulkan --enable-libshaderc --enable- libplacebo --enable-libx264 --enable-libx265 --enable-libxavs2 --enable- libxvid --enable-libzimg --enable-libzvbi --extra- cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-ldexeflags= --extra-libs=-lgomp --extra-version=20220425 libavutil 57. 17.100 / 57. 17.100 libavcodec 59. 18.100 / 59. 18.100 libavformat 59. 16.100 / 59. 16.100 libavdevice 59. 4.100 / 59. 4.100 libavfilter 8. 24.100 / 8. 24.100 libswscale 6. 4.100 / 6. 4.100 libswresample 4. 3.100 / 4. 3.100 libpostproc 56. 3.100 / 56. 3.100 }}} The complete output is given in the file ffmpeg.log -- Ticket URL: <https://trac.ffmpeg.org/ticket/9750> FFmpeg <https://ffmpeg.org> FFmpeg issue tracker

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#9393(trac:new): ban user Balling from trac
by FFmpeg 01 May '22

01 May '22

#9393: ban user Balling from trac -----------------------------------+-------------------------------------- Reporter: richardpl | Type: task Status: new | Priority: critical Component: trac | Version: git-master Keywords: | Blocked By: Blocking: | Reproduced by developer: 0 Analyzed by developer: 0 | -----------------------------------+-------------------------------------- Summary of the bug: User is spamming tickets with pointless entries. -- Ticket URL: <https://trac.ffmpeg.org/ticket/9393> FFmpeg <https://ffmpeg.org> FFmpeg issue tracker

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Re: [FFmpeg-trac] #3356(undetermined:open): feature request: Segment HLS streams on SCTE 35 markers
by FFmpeg 01 May '22

01 May '22

#3356: feature request: Segment HLS streams on SCTE 35 markers -------------------------------------+------------------------------------- Reporter: Adam Thomas | Owner: (none) Type: enhancement | Status: open Priority: wish | Component: | undetermined Version: git-master | Resolution: Keywords: hls bounty | Blocked By: Blocking: | Reproduced by developer: 0 Analyzed by developer: 0 | -------------------------------------+------------------------------------- Comment (by Adrian): Replying to [comment:32 Dennis E. Mungai]: > Replying to [comment:21 jamesdarcy]: > > I am very interested in the solution for this issue and would be willing to add an additional bounty on this issue for AUD $300. > > > > I will want to be able to use this from within an existing c++ that uses ffmpeg libraries. I imagine that that is not an issue. > > > > James > > I'll top this up with 600 AUD. > Getting the HLS and DASH muxers to signal the appropriate SCTE35 CUEs, as shown in this example would be a good start: https://docs.aws.amazon.com/mediaconvert/latest/ug/sample-manifest-scte-35 -enhanced-ad-markers.html > > How can one open a bounty on this? You can pay me directly :) Still interested? I wrote a hls segmenter that cuts segments on SCTE-35 Cues. -- Ticket URL: <https://trac.ffmpeg.org/ticket/3356#comment:33> FFmpeg <https://ffmpeg.org> FFmpeg issue tracker

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