Ffprobe не отражает изменения размеров mp4 ⇐ Python

[Anonymous]

я пытаюсь редактировать ширину и высоту mp4 без масштабирования
я делаю это, редактируя поля tkhd и stsd

• exiftool покажет новую ширину и высоту, но ffprobe нет

before:
$ exiftool $f | egrep -i 'width|height'
Image Width : 100
Image Height : 100
Source Image Width : 100
Source Image Height : 100
$ ffprobe -v quiet -show_streams $f | egrep 'width|height'
width=100
height=100
coded_width=100
coded_height=100

следующий вывод файла Python:
[ftyp] size:32
[mdat] size:196933
[moov] size:2057
- [mvhd] size:108
- [trak] size:1941
- - [tkhd] size:92
Updated tkhd box: Width: 100 -> 300, Height: 100 -> 400
- - [mdia] size:1841
- - - [mdhd] size:32
- - - [hdlr] size:44
- - - [minf] size:1757
- - - - [vmhd] size:20
- - - - [dinf] size:36
- - - - - [dref] size:28
- - - - [stbl] size:1693
- - - - - [stsd] size:145
Updated stsd box #1: Width: 100 -> 300, Height: 100 -> 400
- - - - - [stts] size:512
- - - - - [stss] size:56
- - - - - [stsc] size:28
- - - - - [stsz] size:924
- - - - - [stco] size:20

снова запускаем exiftool и ffprobe:
$ exiftool $f egrep -i 'width|height'
Image Width : 300
Image Height : 400
Source Image Width : 300
Source Image Height : 400
$ ffprobe -v quiet -show_streams $f | egrep 'width|height'
width=100
height=100
coded_width=100
coded_height=100

import sys, struct

def read_box(f):
offset = f.tell()
header = f.read(8)
if len(header) < 8:
return None, offset
size, box_type = struct.unpack(">I4s", header)
box_type = box_type.decode("ascii")
if size == 1:
size = struct.unpack(">Q", f.read(8))[0]
elif size == 0:
size = None
return {"type": box_type, "size": size, "start_offset": offset}, offset

def edit_tkhd_box(f, box_start, new_width, new_height, depth):
f.seek(box_start + 84, 0) # Go to the width/height part in tkhd box
try:
old_width = struct.unpack('>I', f.read(4))[0] >> 16
old_height = struct.unpack('>I', f.read(4))[0] >> 16
f.seek(box_start + 84, 0) # Go back to write
f.write(struct.pack('>I', new_width = parent_size:
break
box, box_start = read_box(f)
if not box:
break
box_type, box_size = box["type"], box["size"]
print(f'{"- " * depth}[{box_type}] size:{box_size}')

if box_type == "tkhd":
edit_tkhd_box(f, box_start, new_width, new_height, depth)
elif box_type == "stsd":
edit_stsd_box(f, box_start, new_width, new_height, depth)

# Recursively parse children if it's a container box
if box_type in ["moov", "trak", "mdia", "minf", "stbl", "dinf", "edts"]:
parse_and_edit_boxes(f, new_width, new_height, depth + 1, box_start + box_size)

if box_size is None:
f.seek(0, 2) # Move to the end of file
else:
f.seek(box_start + box_size, 0)

if __name__ == '__main__':
if len(sys.argv) != 4:
print("Usage: python script.py ")
else:
with open(sys.argv[1], 'r+b') as f:
parse_and_edit_boxes(f, int(sys.argv[2]), int(sys.argv[3]))


Подробнее здесь: https://stackoverflow.com/questions/787 ... sion-edits