tex2img

a texture decompression C++-extension for Python


Keywords
astc, atc, pvrtc, etc, crunch, c-extension, texture, texturepacker
License
MIT
Install
pip install tex2img==0.9.1

Documentation

tex2img

PyPI supported Python versions Win/Mac/Linux MIT Build Status (Travis) Build Status (Github)

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.