Adds peripheral code to make it easier to work with a folder/directory containing mixed content. Tested with S8+ (trailer versions 103, 105 & 106). Coded for Python 3.6.5 64 bit.

fix_eoi.py

#!/usr/bin/python

# The Samsung trailer format is based on the implementation from ExifTool
# http://www.sno.phy.queensu.ca/~phil/exiftool/

# Forked off https://gist.github.com/bcyrill to fit a specific use case,
#  bad pano files mixed with other files in a folder/dir
# The "dump" argument was not tested in this fork
# Meant to be run from a batch like the Windows CMD one in the block comment below
"""
echo off
for %%A in (*.jpg) do python fix_eoi.py "%%A"
echo If everything OK, press any key to delete all *_orig.jpg files
set /p answer="Otherwise close this window to prevent loss of originals ..."
del *_orig.jpg
echo on
"""

import mmap
import struct
import os
import sys
import shutil

if (len(sys.argv) < 2) or (len(sys.argv) > 3):
	print("Usage: fix_eoi.py <filename> [dump]")
	exit()

file_fullname = sys.argv[1]

if len(sys.argv) < 3:
	dump = 0
elif sys.argv[2] == "dump":
	dump = 1
else:
	print("Invalid argument")
	print("Usage: fix_eoi.py <filename> [dump]")
	exit()

(file_name, file_ext) = os.path.splitext(file_fullname)
file_basename = os.path.basename(file_fullname)

if file_ext != '.jpg':
	print(file_basename + ': Doesn\'t have Samsung panoramas standard .jpg extension')
	exit()


with open(file_fullname, 'rb') as fh:
	m = mmap.mmap(fh.fileno(), 0, access=mmap.ACCESS_READ)
	b = bytearray(m)
	
	trailer_tail = b[-4:]
	
	if trailer_tail != bytearray(b'SEFT'):
		print('{}: Expected Samsung (b\'SEFT\') trailer but found {}'.format(file_basename, trailer_tail))
		exit()
	# else:
		# print("Found SEFT")
	
	length = struct.unpack_from("<I",b[-8:-4])[0]	
	trailer = b[-(8+length):]
	
	endPos = len(b)
	dirPos = endPos-(8+length)
	
	if trailer[0:4] != bytearray(b'SEFH'):
		print('{}: Expected Samsung (b\'SEFH\') trailer but found {}'.format(file_basename, trailer[0:4]))
		exit()
	# else:
		# print("Found SEFH")
	
	version = struct.unpack_from("<I",trailer[4:8])[0]
	if version not in set([101, 103, 105, 106]):
		print('{}: Expected Samsung trailer version in [101,103,105,106] but found {}'.format(file_basename, version))
		exit()
	
	count = struct.unpack_from("<I",trailer[8:12])[0]
	
	firstBlock = 0
	is_pano = 0
	
	for index in range(0, count):
		entry = 12 + 12 * index;
		
		type = struct.unpack_from("<H",trailer[entry+2:entry+4])[0]
		noff = struct.unpack_from("<I",trailer[entry+4:entry+8])[0]
		size = struct.unpack_from("<I",trailer[entry+8:entry+12])[0]
		
		if firstBlock < noff:
			firstBlock = noff
		
		entryPos = dirPos - noff
		entryLen = size
		
		data = b[entryPos:entryPos+entryLen]
		
		# Validate as the type has to match the SEFH/SEFT entry type
		entry_type = struct.unpack_from("<H",data[2:4])[0]
		if type != entry_type:
			print(file_basename + ': Block type '+ type + ' doesn\'t match entry type ' + entry_type)
			exit()
			
		entry_offset = struct.unpack_from("<I",data[4:8])[0]
		entry_name = data[8:8+entry_offset].decode("utf-8") 
		
		if entry_name == "Panorama_Shot_Info":
			is_pano = 1
		
		entry_data = data[8+entry_offset:]
		
		if dump:
			print("Dumping: %s" % entry_name)
			with open(file_name + '_' + entry_name, 'wb') as f:
				f.write(entry_data)

	if (not is_pano) and (version < 106): #S8+ stopped adding this entry with trailer v106
		print(file_basename + ': Not a Samsung panorama')
		exit()
	
	dataPos = dirPos - firstBlock
	dirLen = endPos - dataPos
	
	eoi = struct.unpack_from(">H",b[dataPos-2:dataPos])[0]
	if eoi == 0xffd9:
		print(file_basename + ': Already has EOI, not a defective Samsung panorama')
		exit()
	else:
		print(file_basename + ': Inserting EOI to correct defective Samsung panorama')
		with open(file_name + '_fix_eoi.jpg', 'wb') as f:
				f.write(b[0:dataPos])
				f.write(bytearray(b'\xff\xd9'))
				f.write(b[dataPos:])
		m.close()
		fh.close()
		shutil.move(file_fullname, file_name + '_orig.jpg')

I made a rust version which can strip the files of the videos and reduce the size in about half. This version merely makes the file a valid JPEG file but the video remains in there. I also made some binaries if somebody is interested: https://github.com/frapa/sampan