On 23/11/2017 20:02, John Stebbins wrote:
[...] It's not practical to know the duration of the previous subtitle before writing it because you can't know it till you have seen this empty PGS. Once you've seen the empty PGS, it is often too late to properly interleave the previous PGS in the output file.
I argued that on CELLAR mailing list (this is especially true in the case of live streaming) but did not find consensus about the need to have a different semantic for "clear" compared to "display empty subtitle", so for "clear" you have to use "display empty subtitle" thing as a workaround. It may change in the future.
Your suggestion (0 means up to next frame) however works I believe. I.e. display the "empty" PGS up to the next frame.
Right. I actually don't change the code in the patch, just the reason. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
