Unswizzling/Untiling Xbox 360 textures (Call of Duty 4 Modern Warfare)

[0x6D6F]

Semi related to this post but thought I'd make a new post instead of bumping that thread. I am completely new to image formats and currently down a rabbit hole learning about all shorts of shenanigans like swizzling and tiling. I am trying to view a texture a texture dumped from memory from the Xbox 360 version of COD4. Based on other metadata I know the width and height is 1024, 512. I am unsure of the format but I am fairly sure it is DXN or DXT1 DDS image. I don't have the DDS header of the pixel data so I have prepended a DXT1 header for myself.

This is what it looks like without any work except for the prepended DDS header.


My python script which was generated from this c++ untile example takes this image and gives me this output:


Python script

from pathlib import Path


def xg_address_2d_tiled_x(block_offset, width_in_blocks, texel_byte_pitch):
    aligned_width = (width_in_blocks + 31) & ~31
    log_bpp = (texel_byte_pitch >> 2) + (
        (texel_byte_pitch >> 1) >> (texel_byte_pitch >> 2)
    )
    offset_byte = block_offset << log_bpp
    offset_tile = (
        ((offset_byte & ~0xFFF) >> 3)
        + ((offset_byte & 0x700) >> 2)
        + (offset_byte & 0x3F)
    )
    offset_macro = offset_tile >> (7 + log_bpp)

    macro_x = (offset_macro % (aligned_width >> 5)) << 2
    tile = (((offset_tile >> (5 + log_bpp)) & 2) + (offset_byte >> 6)) & 3
    macro = (macro_x + tile) << 3
    micro = (
        (((offset_tile >> 1) & ~0xF) + (offset_tile & 0xF))
        & ((texel_byte_pitch << 3) - 1)
    ) >> log_bpp

    return macro + micro


def xg_address_2d_tiled_y(block_offset, width_in_blocks, texel_byte_pitch):
    aligned_width = (width_in_blocks + 31) & ~31
    log_bpp = (texel_byte_pitch >> 2) + (
        (texel_byte_pitch >> 1) >> (texel_byte_pitch >> 2)
    )
    offset_byte = block_offset << log_bpp
    offset_tile = (
        ((offset_byte & ~0xFFF) >> 3)
        + ((offset_byte & 0x700) >> 2)
        + (offset_byte & 0x3F)
    )
    offset_macro = offset_tile >> (7 + log_bpp)

    macro_y = (offset_macro // (aligned_width >> 5)) << 2
    tile = ((offset_tile >> (6 + log_bpp)) & 1) + ((offset_byte & 0x800) >> 10)
    macro = (macro_y + tile) << 3
    micro = (
        (
            (offset_tile & ((texel_byte_pitch << 6) - 1 & ~0x1F))
            + ((offset_tile & 0xF) << 1)
        )
        >> (3 + log_bpp)
    ) & ~1

    return macro + micro + ((offset_tile & 0x10) >> 4)


def xbox_360_convert_to_linear_texture(data, pixel_width, pixel_height):
    dest_data = bytearray(len(data))
    block_pixel_size = 4
    texel_byte_pitch = 8

    width_in_blocks = pixel_width // block_pixel_size
    height_in_blocks = pixel_height // block_pixel_size

    for j in range(height_in_blocks):
        for i in range(width_in_blocks):
            block_offset = j * width_in_blocks + i
            x = xg_address_2d_tiled_x(block_offset, width_in_blocks, texel_byte_pitch)
            y = xg_address_2d_tiled_y(block_offset, width_in_blocks, texel_byte_pitch)
            src_byte_offset = (
                j * width_in_blocks * texel_byte_pitch + i * texel_byte_pitch
            )
            dest_byte_offset = (
                y * width_in_blocks * texel_byte_pitch + x * texel_byte_pitch
            )

            if dest_byte_offset + texel_byte_pitch > len(dest_data):
                continue
            dest_data[dest_byte_offset : dest_byte_offset + texel_byte_pitch] = data[
                src_byte_offset : src_byte_offset + texel_byte_pitch
            ]

    return dest_data


filename = "viewhands_marine_gloves_col"

dumped_image_data = bytearray(Path(filename).read_bytes())

pixel_width, pixel_height = 1024, 512

linear_texture_data = xbox_360_convert_to_linear_texture(
    dumped_image_data[0x80:], pixel_width, pixel_height
)


dumped_image_data[0x80:] = linear_texture_data

with open("generated_" + filename, "wb") as f:
    f.write(dumped_image_data)

The untiling code looks to have worked but my source and generated images have weird colours, I think perhaps I am missing something or may be using the wrong DDS header but frankly I have no idea what I am doing at this moment. Any help would be appreciated!

Here is the source file with the prepended DDS header.