Please add subtitle support

ExNihilo

New member
Watching several foreign videos, but when I cut a scene/add, all text streams are lost when saving the edited video, rendering the entire video useless to me.

Source:


Or maybe I'm doing something wrong here.
 

cp2

Member
Only certain types of subtitles are supported and then ONLY in certain container types.

""https://videoredo.net/msgBoard/index.php?threads/saving-without-teletext-subtitle-stream.36696/""

I think that Handbreak can "burn in" subtitles (?)
I use TMPGEnc Video Mastering to burn in subtitles but that costs.
I can confirm that Handbrake will burn in sub-titles. I use this when there is foreign audio subtitle. TV broadcasts display these always but some files have them as a separate track. You can't guarantee that any playback device you use will access such tracks so I burn them in.
 

Otter

Member
If you are editing a video with sync'd subs, any edits will throw off whatever comes after the edit and it will get worse with each additional cut.
Each line has as timecode telling when it should be displayed. If you cut from the video, the time codes will still be the same and lines will display at the original time, no longer matching the audio and video
VRD would have to compute and rewrite the timecodes attached to each line displayed and resync all lines in each and every segment differently. Then combine into one synced file or sub stream to mux.
Problem is made worse due to the variety of encoding formats for used for subs.

I've never seen a utility attempt it. There are ones that can do a simple resync with a constant offset, but nothing to deal with multiple different offsets within the same file.

I've done it a couple times, but it was a real time-consuming PITA.
Had to extract/convert subs to plain text .SRT file, then break it up into separate text files with only the subs for each edit segment, then use a utility to offset the timings within each file to sync up with the edit segments, then recombine the text files back into a single SRT and mux it with the other streams using MKVToolNix. PITA!

Don't see why the steps I did couldn't be scripted into VRD, that is what it does now with the video and audio after edits are made, but I think the developers are pretty busy as it is.
 
Last edited:

Danr

Administrator
Staff member
ExNihilo, VideoReDo doesn't support text sub-streams in an MKV file. Can you upload a sample and we will look at what it will take to support.

Otter, For the subtitles are do support we do re-write the time codes. Can you provide more info about what situations this doesn't occur?
 

Otter

Member
DanR, I must be missing something. I've never seen anything in VRD about supporting subtitles.

With a video containing UTF-8, S_TEXT plain text subs loaded, if I go to the Main Menu, no tab has any mention of subs.
I've been thru the program Options and not found any subtitle settings.
Dropping the "Tools, Select Stream" down only lists Video & Audio streams present in the video - no sub stream.
Using "Show Program Info" again lists only V & A - no subs.
Doing either a Fast Recode or full recode yields a file without subs being kept.
Nothing I'm seeing in any Profile is an option dealing with Subs.

What am I not seeing?

Specs for sample file with subs not recognized by VRD:

Format : Matroska
Format version : Version 4
File size : 839 MiB
Duration : 1 h 32 min
Overall bit rate : 1 264 kb/s
Encoded date : UTC 2020-01-06 23:43:32
Writing application : mkvmerge v41.0.0 ('Smarra') 64-bit
Writing library : libebml v1.3.9 + libmatroska v1.5.2

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L3.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference : 4 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 1 h 32 min
Bit rate : 1 067 kb/s
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.046
Stream size : 708 MiB (84%)
Default : Yes
Forced : No
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709

Audio
ID : 2
Format : AAC Main
Format/Info : Advanced Audio Codec
Codec ID : A_AAC-1
Duration : 1 h 32 min
Bit rate : 192 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 SPF)
Compression mode : Lossy
Delay relative to video : 250 ms
Stream size : 129 MiB (15%)
Language : English
Default : Yes
Forced : No

Text
ID : 3
Format : UTF-8
Codec ID : S_TEXT/UTF8
Codec ID/Info : UTF-8 Plain Text
Duration : 1 h 32 min
Bit rate : 102 b/s
Count of elements : 2129
Stream size : 69.1 KiB (0%)
Default : Yes
Forced : No
 

Danr

Administrator
Staff member
Otter, that's what I said. We support teletext and EIA captioning and DVB subtitles. We don't currently support text subtitles.
 

JerryB

Member
For what it's worth, I have a system for editing files in VideoRedo that leads to an MKV file with subtitle support but it requires multiple steps and software products.

1) Process original file in VideoRedo to identify and mark material to be included and excluded in the final output.
2) Output the marked processed file from step 1 as a Transport Stream (match source). This creates a video file that retains appropriately timed subtitle information.
3) WIthout closing VideoRedo or changing any of the marked cutpoints, reoutput the processed file from step 1 as an HEVC MKV file. This creates a video file without any subtitle data. However the audio and video in this file directly match the subtitle information in the file produced in step 2.
4) Use CCExtractor GUI to extract the subtitle data from the file produced in step 2 to an srt file.
5) Use MKVToolNix-GUI to combine the mkv file (lacking subtitles) from step 3 and the extracted subtitle srt file from step 4 into a new MKV file that now contains the appropriate time-matched subtitles.

Although steps 2, 4, and 5 are additional steps that are needed to create an MKV file from VideoRedo with retained subtitle information, they are all very fast so they have minimal effect on overall processing time.
 

Danr

Administrator
Staff member
JerryB, Thanks for the workflow. Can you upload a small mkv sample to us with subs. Thanks.
 

JerryB

Member
I uploaded a 1-minute sample HEVC MKV file with subtitles that I created to folder 37184. Of note, the subtitles display appropriately when the file is played in VLC and/or Plex but not in VideoRedo which I suspect is due to the current version of VideoRedo not knowing how to handle an srt file in an MKV container. The subtitles do display in VideoRedo using the TS version of the file.
 
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