def get_fps(f):
f.seek(0)
mp4.find_atom(f, b'moov')
moov = mp4.parse_atom(f)
for trak in moov.find(b'trak'):
if trak.find(b'vmhd'):
video_trak = trak
break
else:
raise Exception('FPS: No video track found')
stts = video_trak.find(b'stts')[0]
mdhd = video_trak.find(b'mdhd')[0]
stts_entries = struct.unpack('>I', stts.data[4:4 + 4])[0]
sum_samples = 0
sum_delta = 0
for i in range(stts_entries):
offset = 8 + i * 8
num_samples = struct.unpack('>I', stts.data[offset:offset + 4])[0]
sum_samples += num_samples
sum_delta += num_samples * struct.unpack(
'>I', stts.data[offset + 4:offset + 8])[0]
denom = round(sum_delta / sum_samples)
numer = struct.unpack('>I', mdhd.data[12:12 + 4])[0]
return numer, denom
def set_fps(f, numer, denom):
f.seek(0)
mp4.find_atom(f, b'moov')
moov_offset = f.tell()
moov = mp4.parse_atom(f)
for trak in moov.find(b'trak'):
if trak.find(b'vmhd'):
video_trak = trak
break
else:
raise Exception('FPS: No video track found')
stts = video_trak.find(b'stts')[0]
mdhd = video_trak.find(b'mdhd')[0]
stts_entries = struct.unpack('>I', stts.data[4:4 + 4])[0]
num_samples = 0
for i in range(stts_entries):
offset = 8 + i * 8
num_samples += struct.unpack('>I', stts.data[offset:offset + 4])[0]
stts.data[offset + 4:offset + 8] = struct.pack('>I', denom)
mdhd.data[12:12 + 8] = struct.pack('>II', numer, num_samples * denom)
f.seek(moov_offset)
f.write(moov.flatten())
import mp4
import sys, struct, shutil, os
outname = os.path.basename(sys.argv[1])
name, ext = os.path.splitext(outname)
outname = name + '_org_fps' + ext
print(outname)
f = open(sys.argv[1], 'rb')
mp4.find_atom(f, b'moov')
moov_offset = f.tell()
moov = mp4.parse_atom(f)
for trak in moov.find(b'trak'):
if trak.find(b'vmhd'):
video_trak = trak
break
else:
sys.exit(1)
#stsz = video_trak.find(b'stsz')[0]
stts = video_trak.find(b'stts')[0]
mdhd = video_trak.find(b'mdhd')[0]
#num_samples = struct.unpack('>I', stsz.data[8:8+4])[0]
#stts.data[4:] = struct.pack('>III', 1, num_samples, 1001)
stts_entries = struct.unpack('>I', stts.data[4:4 + 4])[0]
num_samples = 0
for i in range(stts_entries):
offset = 8 + i * 8
num_samples += struct.unpack('>I', stts.data[offset:offset + 4])[0]
stts.data[offset + 4:offset + 8] = struct.pack('>I', 1000)
def parse_time(t):
t = t.split(':')
ts = 0
for i, p in enumerate(reversed(t)):
ts += float(p) * 60**i
return ts
if len(sys.argv) > 3:
bb_offset1, bb_time1, bb_offset2, bb_time2 = map(parse_time,
sys.argv[3:3 + 4])
else:
bb_offset1 = parse_time(sys.argv[3])
bb_time1, bb_offset2, bb_time2 = None, None, None
mp4.find_atom(fin, b'moov')
moov = mp4.parse_atom(fin)
fin.seek(0)
mdat_data_size = mp4.find_atom(fin, b'mdat') - mp4.ATOM_HEAD_SIZE
mdat_data_offset = fin.tell() + mp4.ATOM_HEAD_SIZE
#print(moov)
# video_trak = None
# audio_trak = None
# for trak in moov.find(b'trak'):
# if trak.find(b'vmhd'):
# video_trak = trak
# elif trak.find(b'smhd'):
# audio_trak = trak
#