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@bcyrill
Created August 28, 2016 14:58
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Python script to inject the EOI marker into panoramic photos created by the S7 camera. In addition the script allows to dump the Samsung specific data that is added to the image
#!/usr/bin/python
# The Samsung trailer format is based on the implementation from ExifTool
# http://www.sno.phy.queensu.ca/~phil/exiftool/
import mmap
import struct
import os
import sys
if (len(sys.argv) < 2) or (len(sys.argv) > 3):
print("Usage: fix_eoi.py <filename> [dump]")
exit()
file = 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)
with open(file, 'rb') as fh:
m = mmap.mmap(fh.fileno(), 0, access=mmap.ACCESS_READ)
b = bytearray(m)
trailer_tail = b[-4:]
if trailer_tail != 'SEFT':
print("No valid Samsung trailer found")
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] != 'SEFH':
print("No valid Samsung trailer found")
exit()
else:
print("Found SEFH")
version = struct.unpack_from("<I",trailer[4:8])[0]
if version != 101:
print("Unknown Samsung trailer 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("Missmatch detected. Aborting!")
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:
print "No Panorama info found"
exit()
dataPos = dirPos - firstBlock
dirLen = endPos - dataPos
eoi = struct.unpack_from(">H",b[dataPos-2:dataPos])[0]
if eoi == 0xffd9:
print("Found EOI")
exit()
else:
print("Inserting EOI")
with open(file_name + '_pano' + file_ext, 'wb') as f:
f.write(b[0:dataPos])
f.write(bytearray(b'\xff\xd9'))
f.write(b[dataPos:])
@frapa
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frapa commented Jul 25, 2021

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

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