Issues while recreating a TIFF file with 1D encoded data - c

This is regarding Fax Image compression. Initially I had an Uncompressed TIFF file , I wrote a code to extract its tags and the Image data present in it. Once I extracted the image data I performed 1D modefied Huffman coding/ Run length coding on it to get the encoded compressed data which I have stored in a textfile.
Now I am trying to recreate a TIFF file by modifying the tags appropriately to store the encoded compressed data. I have writen a code to recreate the tiff file and when I open the tiff file with an appliction to view all the tags, I find that all the tags I have put are correctly being read. However, when I use an online tiff viewer I do not get the correct image. I am confident that my encoded data is correct according to the Huffman Runlength tables. Anyone has any idea why I am not able to view the same Image with my compressed tiff file?
Note : I have not used any C libraries such as libtiff, The tiff file is just created by opening a tiff file and writing specific values at different offsets based on the tiff file stucture.
Thank you.
The Original Uncompressed file
The 1D encoded compressed file

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EDIT
PURPOSE OF ALL THIS:
I want to do all this for encryption. As by encrypting a file (using AES) the whole file will become unreadable, corrupt and everything inside will be changed from its place. When I decrypt that file, the file is unable to open. My guess is, as AES decryption algo does not know how to parse the contents recovered from decrypting the encrypted file, in to a new .docx file, thus it is unable to place the contents/structure properly in its place.
I have tried it. Original docx file was of 14 KB, encrypted docx file was of 14 KB as well as the decrypted docx file. But when I try to open the decrypted file, it says file is corrupt. Also I tried to check it in HEX editor. Decrypted file has just 00 bytes after exactly 30 Bytes.
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