hex change the dwHeight value inside an .avi via commandline?

[marcorocchini]

Hi

IF the cats. Anyway

please I wonder if does exist a way to change, via commandline in windows, the height value tag of an .avi file like this temp.avi

https://www.swisstransfer.com/d/c6be6f53-50c7-4f8f-87dc-365d232a4f47

so that the height internal tag change from the originally 1088 to 1080

hex change from 4008 into 3808 in 3 points

from


[Attachment 73097 - Click to enlarge]

to


[Attachment 73096 - Click to enlarge]


thanks

[jagabo]

PowerShell

[marcorocchini]

ah yes, but compliCat

[_Al_]

I did what you wanted three changes, no problem to post python script to use in batch or even make an exe to run it with arguments,

but I did those changes in avi header on pos 44, then it seams to be following video stream header bytes 54 (2bytes) and 72 (4bytes) changes, but mediainfo still reports original height 1088. Is that file suppose to be fixed?

[marcorocchini]

oh wowcat

[marcorocchini]

but yes the temp_1080.avi is recognized as 1080 correctly, my mediainfo tell 1088 il the original height but this is not a problem: the height value is 1080

another .avi example:

https://www.swisstransfer.com/d/3d48c3e1-968c-4e1e-96b5-b0333ab94dcd

https://www.swisstransfer.com/d/06d514ec-5fbd-4aa0-b4fc-b750995f8c7b

also this other .avi mjpeg files are intimately 1920x1080 but written in stream copy modee by ffmpeg which however marks them as 1088

[jagabo]

I did what you wanted three changes, no problem to post python script to use in batch or even make an exe to run it with arguments,

but I did those changes in avi header on pos 44, then it seams to be following video stream header bytes 54 (2bytes) and 72 (4bytes) changes, but mediainfo still reports original height 1088. Is that file suppose to be fixed?

MediaInfo reports the same about his source files too, height 1080, original height 1088.

[_Al_]

based on this, this python script was made, you can use this python file in your batch script if you have python installed, usage as python is in there:

import os
import sys

def load_value(avi_path, offset, length):
    with open(avi_path,'rb') as f:
        f.seek(offset,0)
        return int.from_bytes(f.read(length), byteorder='little')

def get_offset(avi_path, string):
    with open(avi_path,'rb') as f:
        offset = 0
        f.seek(0)
        while (buff := f.read(16)):
            if string in buff:
                return offset + buff.index(string) 
            else:
                offset += 16
        else:
            print(f'  avi header with fcc type: "{string.decode()}" not found, avi header not found  in {avi_path}')
            return None

def overwrite_bytes(avi_path, offset, new_integer, length):
    with open(avi_path,'r+b') as f:
        f.seek(offset,0)
        bytes_val = new_integer.to_bytes(length, 'little')
        f.write(bytes_val)

def main(avi_path, new_dwHeight):
    new_dwHeight = int(new_dwHeight)
    avih_offset = get_offset(avi_path, b'avih')
    if avih_offset is not None:
        dwHeight = load_value(avi_path, avih_offset + 44, 4)
        overwrite_bytes(avi_path, avih_offset + 44, new_dwHeight, 4)
        print(f'  avih pos 44: {dwHeight} to {new_dwHeight}  {avi_path}')
    vids_offset = get_offset(avi_path, b'vids')
    if vids_offset is not None:
        dwHeight = load_value(avi_path, vids_offset + 54, 2)
        overwrite_bytes(avi_path, vids_offset + 54, new_dwHeight, 2)
        print(f'  vids pos 54: {dwHeight} to {new_dwHeight}  {avi_path}')
        dwHeight = load_value(avi_path, vids_offset + 72, 4)
        overwrite_bytes(avi_path, vids_offset + 72, new_dwHeight, 4)
        print(f'  vids pos 72: {dwHeight} to {new_dwHeight}  {avi_path}')

if __name__ == '__main__':
    '''
    usage, this should change mjpg avi to height 1080 if using python in cmd prompt:
    python  change_avi_height.py  filename.avi  1080
    '''

    args = []
    for arg in sys.argv[1:]:
        args.append(arg)
    if len(args) < 2:
        raise ValueError('Two arguments needed. First argument is avi filename, second is new height')
    for i, arg in enumerate(args[:2]):
        if i==0:
            if not os.path.isfile(arg) or not arg.lower().endswith('.avi'):
                raise ValueError(f'First argument must be existing avi filepath. Got: {arg}')
        else:
            try:
                int(arg)
            except (TypeError, ValueError):
                raise ValueError(f'Second height argument must be an integer. Got: {arg}')
    print(f'Changing avi header heights for files to: {args[1]}')
    main(*args)

If not having python, you need exe file.
If having python, you can make exe file yourself, install pyinstaller in cmd prompt:

pip install PyInstaller

then use command (make sure there is your current python installed version like 38, 39 or latest 311):

"C:\Users\*** user name ***\AppData\Roaming\Python\Python38\Scripts\pyinstaller.exe"  "*** your path to python file ***\change_avi_height.py" --name "change height in mjpg avi"  -–onefile

then in directory where your change_avi_height.py is you will find dist directory and in there your compiled EXE file you can use in batch scripts, usage is:

"change height in mjpg avi.exe"  "filenami.avi" 1080

zip with that exe file:

[marcorocchini]

[Attachment 73103 - Click to enlarge]

oh wow it works
absoluty useful (but I don't understand how you did it, but everything is fine)

it changes very well

[Attachment 73104 - Click to enlarge]

oh my ***

thanks

[_Al_]

MediaInfo reports the same about his source files too, height 1080, original height 1088.

Samples he provided, temp.avi and temp2.avi does not show original height 1088 though, I might have some old mediainfo version (21.03), not sure.

[marcorocchini]

my old version of mediainfo 0.7.90 over the modify temp.avi report:

Generale
Complete name                            : C:\temp.avi
Format                                   : AVI
Format/Info                              : Audio Video Interleave
Format profile                           : OpenDML
File size                                : 2,65 GiB
Duration                                 : 1 min 34s
Overall bit rate                         : 242 Mb/s
Writing application                      : Lavf59.16.100

Video
ID                                       : 0
Format                                   : JPEG
Codec ID                                 : MJPG
Duration                                 : 1 min 34s
Bit rate                                 : 242 Mb/s
Width                                    : 1.920 pixel
Height                                   : 1.080 pixel
Original height                          : 1.088 pixel
Display aspect ratio                     : 16:9
Frame rate                               : 25,000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:2
Bit depth                                : 8 bit
Scan type                                : Interlacciato
Scan order                               : Top field first
Compression mode                         : Con perdita
Bits/(Pixel*Frame)                       : 4.677
Stream size                              : 2,65 GiB (100%)

I think ffmpeg have at least a "problem": when concatenate multiple .avi mpeg files that are 1920x1080 --> generate a final output strangely 1920X1088

however your programs works fine

[jagabo]

MediaInfo reports the same about his source files too, height 1080, original height 1088.

Samples he provided, temp.avi and temp2.avi does not show original height 1088 though, I might have some old mediainfo version (21.03), not sure.

I was referring to his source images in another thread where he was concatenating two MJPEG AVI files into one. That's the cause of the 1088 line problem in the videos here.

https://forum.videohelp.com/threads/410710-how-to-merge-multiple-avi-mjpeg-files#post2700803