When transcoding some series, I have noticed that some texts within the subtitles are lost.
Not entire tracks are lost, but only individual text passages.
On closer examination, I realized that the problem occurs with graphics-based subtitles (e.g. pgs subtitles). To be precise, if 2 subtitle displays come one right after the other, the duration of the first display is extended by the duration of the second display and the second display disappears.
Example:
Source:
Code: Select all
00:00:06,881 --> 00:00:09,800
Line 0
00:00:09,801 --> 00:00:13,762
Line 1
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00:00:06,881 --> 00:00:13,762
Line 0
I exported the subtitles with "MKVcleaver" and viewed them with "SubRip1.16" as part of my research.
Don't get me wrong, the problem was already in the transcoded .mkv file which I checked with the VLC player.
I have tested it several times with different series and also tried other sources.
Steps to reproduce the problem (If Applicable):
I use the handbrake GUI in the latest version (1.7.3 (2024021000))
I use my own preset, which is based on the "HQ 2160p 4k AV1" preset.
I have customized:
- summary => file format as .mkv
- summary => passthru common metadata
- video=> AV1 10-bit, 18RF, framerate same as source, variable framerate, encoder preset 7
- use all audio/subtitles
Everything else stayed the same.
I also switched between constant and variable for the frame rate.
HandBrake version (e.g., 1.0.0):
1.7.3 (2024021000)
But I had the problem also in 1.7.1.
Operating system and version (e.g., Ubuntu 16.04 LTS, macOS 10.13 High Sierra, Windows 10 Creators Update):
Windows 10/Windows 11 in the last few months.
HandBrake Activity Log ***required*** (see How-to get an activity log)
The log from the "extended" log verbosity level:
https://pastebin.com/gwBXPMsE
(I censored the input/output file with "*****", but it was a .mkv file)
The problem occurs when the following appears in the log, usually several entries with different PTS values:
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sync: subtitle 0x5 time went backwards 0 ms, PTS 882090