FFmpeg: Exporting subtitle stream to .ass file

Question

What I'm trying to do is exporting the subtile stream of a MKV-file to a ASS-subtitle-file. I'm not really experienced with ffmpeg so I'm sorry if I miss something obvious

This is what I've got so far:

ffmpeg -i input.mkv -map 0:7 -c:s ass output_subtitle.ass

But when I try to run it, it gives me the error "Only SUBTITLE_ASS type supported"

Solution 1

try this

ffmpeg -i input.mkv -map 0:{subtitle_stream_index} -c copy output_subtitle.ass

assuming the subtitle stream index is 7 from your question then the command will be

ffmpeg -i input.mkv -map 0:7 -c copy output_subtitle.ass

Solution 2

You should try this: ffmpeg -i input.mkv -vn -an -codec:s:0.7 ass output_subtitle.ass assuming you have found out the stream identifier to be 0:7.

Comments

[Kard Nails]

By the way, why not use str?

[Kard Nails]

Lighter, simpler, more widely supported and it's not like ass has that much to offer that str hasn't. Unless you want some really fancy formatting.

[YourMJK]

Well, how do you define "fancy formatting"? The subtitle got a custom font and color :D

[Elisa Cha Cha]

Please include the complete ffmpeg console output.

[YourMJK]

Too long to post here...

[Elisa Cha Cha]

Nobody has said that before. You may, of course, omit multiple repeating lines. If you are unsure just provide the first ~50 and last ~50 lines.

[YourMJK]

Well I found a line that may be interesting: [matroska,webm @ 0x7fb421018600] Could not find codec parameters for stream 7 (Subtitle: hdmv_pgs_subtitle): unspecified size Consider increasing the value for the 'analyzeduration' and 'probesize' options'

[YourMJK]

And the last lines: Chapter #0.1: start 325.575250, end 612.278333 Metadata: title : Chapter 02 […] (Lots of chapters) Stream #0:0(eng): Subtitle: ass Metadata: title : Untertitel Stream mapping: Stream #0:4 -> #0:0 (pgssub -> ass) Press [q] to stop, [?] for help [ass @ 0x7fb422417c00] Only SUBTITLE_ASS type supported. Subtitle encoding failed

[YourMJK]

Thanks for the answer but somehow it still gives me the same error. Maybe it is relevant that the subtitle stream has a pgssub codec?

[Kard Nails]

Have you tried to export str instead?

[YourMJK]

Yes, I did but it leaves me with a new error: "Error while opening encoder for output stream #0:0 - maybe incorrect parameters such as bit_rate, rate, width or height" Command I used: ffmpeg -i input.mkv -vn -an -codec:s:0.7 srt output_subtitle.srt

[YourMJK]

Wait, I'm confused. Is it "SRT" or "STR"?!