Backslashes cannot be escaped by backslashes in any ASS renderer, but unless followed by a few specific characters it is just printed as a regular character. Insert a word-joiner character after a backslash to break up the active sequences without changing the visual output. Also the existing \{ and \} escapes are specific to libass only. --- The patch assumes UTF-8 encoding in ff_ass_bprint_text_event (WebVTT requires UTF-8 per sepc). If we cannot assume a particular encoding, please advise how to best insert a word-joiner character in the correct encoding. --- libavcodec/ass.c | 5 ++++- libavcodec/webvttdec.c | 2 +- 2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/libavcodec/ass.c b/libavcodec/ass.c index 725e4d42ba..461e110ca4 100644 --- a/libavcodec/ass.c +++ b/libavcodec/ass.c @@ -157,8 +157,11 @@ void ff_ass_bprint_text_event(AVBPrint *buf, const char *p, int size, /* standard ASS escaping so random characters don't get mis-interpreted * as ASS */ - } else if (!keep_ass_markup && strchr("{}\\", *p)) { + } else if (!keep_ass_markup && strchr("{}", *p)) { av_bprintf(buf, "\\%c", *p); + } else if (!keep_ass_markup && *p == '\\') { + // append word-joiner U+2060 as UTF-8 to break up sequences like \N + av_bprintf(buf, "\\\xe2\x81\xa0"); /* some packets might end abruptly (no \0 at the end, like for example * in some cases of demuxing from a classic video container), some diff --git a/libavcodec/webvttdec.c b/libavcodec/webvttdec.c index 0093f328fa..8cb739697a 100644 --- a/libavcodec/webvttdec.c +++ b/libavcodec/webvttdec.c @@ -37,7 +37,7 @@ static const struct { {"<i>", "{\\i1}"}, {"</i>", "{\\i0}"}, {"<b>", "{\\b1}"}, {"</b>", "{\\b0}"}, {"<u>", "{\\u1}"}, {"</u>", "{\\u0}"}, - {"{", "\\{"}, {"}", "\\}"}, // escape to avoid ASS markup conflicts + {"{", "\\{"}, {"}", "\\}"}, {"\\", "\\\xe2\x81\xa0"}, // escape to avoid ASS markup conflicts {">", ">"}, {"<", "<"}, {"‎", ""}, {"‏", ""}, // FIXME: properly honor bidi marks {"&", "&"}, {" ", "\\h"}, -- 2.30.2 _______________________________________________ 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".