[Libav-user] Question regarding VP9 (AV_CODEC_ID_VP9) - forcing alpha

2021-03-16 Thread David Rappo
Hi, I wrote a small program based on the FFMPEG example doc/examples/demuxing_decoding.c to extract the frames from an input video and save them out as PNG files. This works but the output frames are missing alpha information. In this case the input file is WebM and the decoder used is VP9 (AV_CO

Re: [Libav-user] Question regarding VP9 (AV_CODEC_ID_VP9) - forcing alpha

2021-03-17 Thread Carl Eugen Hoyos
Am Mi., 17. März 2021 um 07:08 Uhr schrieb David Rappo : > const auto codecIdentifier{ AV_CODEC_ID_VP9 }; > auto decoder = avcodec_find_decoder(codecIdentifier); Note that this looks very different from "ffmpeg -c:v libvpx-vp9 -i anim.webm" > Does anybody know how to force FFMPEG to open the inp