tex2img

A texture decompression C++-extension for Python.

1. Installation
2. Notes
3. Functions
4. Sources

Installation

pip install tex2img

or download/clone the git and use

python setup.py install

Notes

• etcpack causes a segfault on linux systems, so linux systems will use basisu under the hood for etc instead

Functions

All functions accept only args and aren't able to handle kwards atm.

basisu_decompress

Decompresses data to RGBA via basisu's unpack_block function.

Args: (compressed data: bytes, width: int, height: int, format: int)

Returns: bytes

Formats:

| Format | Mode | Note | |--------|------------------------------|-----------------------------------------------| | 0 | cETC1 | ETC1 | | 1 | cETC1S | ETC1(subset:diff colors only, no subblocks) | | 2 | cETC2_RGB | ETC2 color block | | 3 | cETC2_RGBA | ETC2 alpha block followed by ETC2 color block | | 4 | cETC2_ALPHA | ETC2 EAC alpha block | | 5 | cBC1 | DXT1 | | 6 | cBC3 | DXT5(DXT5A block followed by a DXT1 block) | | 7 | cBC4 | DXT5A | | 8 | cBC5 | 3DC / DXN(two DXT5A blocks) | | 9 | cBC7 | | | 10 | cASTC4x4 | | | 11 | cPVRTC1_4_RGB | | | 12 | cPVRTC1_4_RGBA | | | 13 | cATC_RGB | | | 14 | cATC_RGBA_INTERPOLATED_ALPHA | | | 15 | cFXT1_RGB | | | 16 | cPVRTC2_4_RGBA | | | 17 | cETC2_R11_EAC | | | 18 | cETC2_RG11_EAC | |

decompress_astc

Decompresses raw astc-compressed data to RGBA.

Args: (compressed data: bytes, image width: int, image height: int, block_width: int, block_height: int, isSRGB: False)

Returns: bytes

decompress_atc

Decompresses raw atc-compressed data to RGB(A).

Args: (compressed data: bytes, width: int, height: int, alpha: bool)

Returns: bytes

alpha = False for ATC_RGB alpha = True for ATC_RGBA

decompress_pvrtc

Decompresses raw pvrtc-compressed data to RGBA.

Args: (compressed data: bytes, width: int, height: int, do2bit_mode: 0)

Returns: bytes

decompress_etc

Decompresses raw etc-compressed data to RGB(A).

Args: (compressed data: bytes, width: int, height: int, format: int)

This function has a memory leak, so it might crash if you use it on too many images at once (~500+). The basisu_decompress function also supports the most common ETC formats, so it is a good alternative.

Formats:

| Format | Mode | |--------|----------------------------------| | 0 | ETC1_RGB_NO_MIPMAPS | | 1 | ETC2PACKAGE_RGB_NO_MIPMAPS | | 2 | ETC2PACKAGE_RGBA_NO_MIPMAPS_OLD | | 3 | ETC2PACKAGE_RGBA_NO_MIPMAPS | | 4 | ETC2PACKAGE_RGBA1_NO_MIPMAPS | | 5 | ETC2PACKAGE_R_NO_MIPMAPS | | 6 | ETC2PACKAGE_RG_NO_MIPMAPS | | 7 | ETC2PACKAGE_R_SIGNED_NO_MIPMAPS | | 8 | ETC2PACKAGE_RG_SIGNED_NO_MIPMAPS | | 9 | ETC2PACKAGE_sRGB_NO_MIPMAPS | | 10 | ETC2PACKAGE_sRGBA_NO_MIPMAPS | | 11 | ETC2PACKAGE_sRGBA1_NO_MIPMAPS |

crunch_get_texture_info

Retrieves texture information from the CRN file.

Args: (data: bytes)

Returns: dict

crunch_get_level_info

Retrieves mipmap level specific information from the CRN file.

Args: (data: bytes, mipmap_leve: int)

Returns: dict

crunch_unpack_level

Transcodes the specified mipmap level to a destination buffer.

Args: (data: bytes, mipmap_level: int)

Returns: bytes

Sources

ATC & ASTC

The complete BinomialLLC/basis_universal is used and supported. It's default for the ATC and ASTC decompression.

ETC

The whole source of Ericsson/ETCPACK is used for the ETC decompression.

PVRTC

PVRTDecompress.cpp and PVRTDecompress.h of powervr-graphics/Native_SDK are used for the PVRTC decompression.

crunch

A mixed version of BinomialLLC/crunch and Unity-Technologies/crunch is used.

The Unity fork doesn't yield correct results for the original modes, so the BiomialLLC version is used for all modes besides ETC, which was created byUnity.