invalid start byte / subtitle encoding (...) text to text or bitmp to bitmap

[mavhamm]

Hi, great program!

Recently I haven't been able to make it work on any new downloads. I'm on Windows10, using v1.3.1

Here's the info on this mkv: https://prnt.sc/pfuBqRiW-Ngp
Here is the srt: https://www.mediafire.com/folder/bg354za9xfn7q/condenser_issue_2023-01

Log when it uses the internal subtitle file

Could not extract subtitle with ffmpeg: b'Subtitle encoding currently only possible from text to text or bitmap to bitmap\r\n'
Traceback:
Traceback (most recent call last):
  File "condenser.py", line 353, in main
  File "condenser.py", line 184, in get_srt
  File "condenser.py", line 161, in extract_srt
Exception: Could not extract subtitle with ffmpeg: b'Subtitle encoding currently only possible from text to text or bitmap to bitmap\r\n'

Log when it uses the external srt subtitle

'utf-8' codec can't decode byte 0x92 in position 0: invalid start byte
Traceback:
Traceback (most recent call last):
  File "condenser.py", line 357, in main
  File "condenser.py", line 211, in condense
  File "condenser.py", line 72, in extract_periods
  File "lib\site-packages\pysrt\srtfile.py", line 153, in open
  File "lib\site-packages\pysrt\srtfile.py", line 181, in read
  File "C:\Users\xerca\AppData\Local\Programs\Python\Python37\lib\collections\__init__.py", line 1127, in extend
  File "lib\site-packages\pysrt\srtfile.py", line 204, in stream
  File "C:\Users\xerca\AppData\Local\Programs\Python\Python37\lib\codecs.py", line 714, in __next__
  File "C:\Users\xerca\AppData\Local\Programs\Python\Python37\lib\codecs.py", line 645, in __next__
  File "C:\Users\xerca\AppData\Local\Programs\Python\Python37\lib\codecs.py", line 558, in readline
  File "C:\Users\xerca\AppData\Local\Programs\Python\Python37\lib\codecs.py", line 504, in read
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x92 in position 0: invalid start byte

[ercanserteli]

It seems that your mkv's subtitle stream type is PGS which stands for Presentation Graphic Stream Subtitle Format, and since it is a bitmap (image) format ffmpeg can't extract it to a srt file that condenser can read. This is something I can't support for now, but I welcome anyone who would like to implement a solution with a pull request.

The second problem with the srt file has to be a different problem, but it seems the file on mediafire got deleted. If you are still interested, I would be happy if you could re-upload the problematic srt file.