Perfect synchronization is lost after ~5 minutes. Re-sync every 5 minutes.

Writing eng subtitles to subtitles.srt...
00:00:00,583 (0.64) - 00:00:00,625 (5.73) <skipped: too quick>
00:00:00,709 (0.33) - 00:00:00,750 (24.02) <skipped: too quick>
00:00:01,376 (2.54) - 00:00:01,584 (5.09) <skipped: too quick>
00:00:05,588 (4.73) - 00:00:07,257 (5.09) Traceback (most recent call last):
File "meltsub.py", line 263, in
extract_subs(f, softsub_video, hardsub_video, pos_diff_sec)
File "meltsub.py", line 228, in extract_subs
text = ocr(sub_frame)
File "meltsub.py", line 114, in ocr
p.stdin.write(buf)
BrokenPipeError: [Errno 32] Broken pipe

It seems to work but when it detects the subtitle it generates an error:

clover@Aqours:~/sub-ocr/meltsub-master$ python3 meltsub.py
...
00:00:15,306 (4.44) - 00:00:15,390 (5.41) <skipped: too quick>
00:00:15,432 (4.44) - 00:00:16,057 (5.19) Traceback (most recent call last):
File "meltsub.py", line 261, in
extract_subs(f, softsub_video, hardsub_video, pos_diff_sec)
File "meltsub.py", line 227, in extract_subs
text = ocr(sub_frame)
File "meltsub.py", line 113, in ocr
p.stdin.write(buf)
BrokenPipeError: [Errno 32] Broken pipe

Other info:

clover@Aqours:$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 18.04.1 LTS
Release: 18.04
Codename: bionic
clover@Aqours:$ python3 --version
Python 3.6.7
clover@Aqours:~$ tesseract -v
tesseract 4.0.0-beta.1
leptonica-1.75.3
libgif 5.1.4 : libjpeg 8d (libjpeg-turbo 1.5.2) : libpng 1.6.34 : libtiff 4.0.9 : zlib 1.2.11 : libwebp 0.6.1 : libopenjp2 2.3.0

Found AVX2
Found AVX
Found SSE