Em seg, 29 de abr de 2019 às 00:06, <xwm...@pku.edu.cn> escreveu: > > > > > > -----原始邮件----- > > 发件人: "Pedro Arthur" <bygran...@gmail.com> > > 发送时间: 2019-04-29 10:42:42 (星期一) > > 收件人: "FFmpeg development discussions and patches" <ffmpeg-devel@ffmpeg.org> > > 抄送: > > 主题: Re: [FFmpeg-devel] [PATCH] libavfilter: Add more operation supports in > > FFmpeg dnn native mode. > > > > I think for training these filters the preferred method is VALID as it > > uses only the data available (without filling the borders) and gives > > the best possible result. > > However for inference usually one expects to output an image with the > > same size of the original (imagine the case of chained filters where > > each one reduces the image by a few pixels, in the end one may have a > > useless output). > > Therefore it makes perfect sense to use different padding methods for > > training/inference. > > > > The clamp_to_edge padding was introduced before the TF backend thus it > > stayed in the native backend even after the introduction of the TF > > backend. > > Indeed the clamp_to_edge is simpler than the other padding methods and > > also gives a slight better result, If I remember correct the student > > which implemented the TF backend did not find an equivalent padding > > method in TF, thats why it uses different paddings. > > > Yes, I think clamp_to_edge is a good method to keep the output with the same > size as input. However, I don't think "VALID" is the best method giving best > possible result. So, for "VALID" mode, maybe we can use the clamp_to_edge > method in the current dnn native mode? And then, we should also add "SAME" > option to support other filters. >
I think it is best to not make any assumptions like VALID => clamp_to_edge, but you can keep it for now. Ideally the model should have a padding layer which the backend properly implements. Currently the TF backend when reading a native model adds this padding layer implicitly, therefore it would be a matter of changing it to have an explicity padding layer in the model. Maybe you can assume VALID => clamp_to_edge, so you can add what you need without changing the SR code and later you implement the explicity padding support and send a PR to the original repo (https://github.com/HighVoltageRocknRoll/sr) properly modifying the model. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
