PySquish

pysquish.cpp

// Squish bindings for python 
// http://stackoverflow.com/questions/10972595/dxt-compression-for-python
// modify Stardrad

#include <squish.h>
#include "pysquish.h"


extern "C" {
    void CompressMasked(u8 const* rgba, int mask, void* block, int flags) {
        squish::CompressMasked(rgba, mask, block, flags);
    }

    void Compress(u8 const* rgba, void* block, int flags) {
        squish::Compress(rgba, block, flags);
    }

    void Decompress(u8* rgba, void const* block, int flags) {
        squish::Decompress(rgba, block, flags);
    }

    int GetStorageRequirements(int width, int height, int flags) {
        return squish::GetStorageRequirements(width, height, flags);
    }

    void CompressImage(u8 const* rgba, int width, int height, void* blocks, int flags) {
        squish::CompressImage(rgba, width, height, blocks, flags);
    }

    void DecompressImage(u8* rgba, int width, int height, void const* blocks, int flags) {
        squish::DecompressImage(rgba, width, height, blocks, flags);
    }
}

pysquish.hpp

// Squish bindings for python 
// http://stackoverflow.com/questions/10972595/dxt-compression-for-python
// modify Stardrad

#ifndef PYSQUISH
#define PYSQUISH
typedef unsigned char u8;
extern "C"
{
#define DllExport    __declspec( dllexport )

    DllExport void CompressMasked(u8 const* rgba, int mask, void* block, int flags);
    DllExport void Compress(u8 const* rgba, void* block, int flags);

    DllExport void Decompress(u8* rgba, void const* block, int flags);

    DllExport int GetStorageRequirements(int width, int height, int flags);

    DllExport void CompressImage(u8 const* rgba, int width, int height, void* blocks, int flags);

    DllExport void DecompressImage(u8* rgba, int width, int height, void const* blocks, int flags);
}

#endif // !PYSQUISH

pysquish.py

# Squish bindings for python 
# http://stackoverflow.com/questions/10972595/dxt-compression-for-python

from ctypes import CDLL, c_int, byref, create_string_buffer
import os.path

libsquish_path = os.path.join(os.path.split(os.path.abspath(__file__))[0], 'libsquishc.so')
libsquish = CDLL(libsquish_path)


DXT1 = 1 << 0 
DXT3 = 1 << 1 
DXT5 = 1 << 2 

COLOR_ITERATIVE_CLUSTER_FIT = 1 << 8    
COLOR_CLUSTER_FIT = 1 << 3    
COLOR_RANGE_FIT = 1 << 4
WEIGHT_COLOR_BY_ALPHA = 1 << 7


GetStorageRequirements = libsquish.GetStorageRequirements
GetStorageRequirements.argtypes = [c_int, c_int, c_int]
GetStorageRequirements.restype = c_int

def compress_image(rgba, width, height, flags):
    rgba = create_string_buffer(rgba)

    c = GetStorageRequirements(width, height, flags)
    buffer = create_string_buffer(c)

    libsquish.Compress(byref(rgba), byref(buffer), c_int(flags))

    return buffer.raw

def decompress_image(block, width, height, flags):
    block = create_string_buffer(block)

    c = width*height*4
    rgba = create_string_buffer(c)

    libsquish.DecompressImage(byref(rgba), c_int(width), c_int(height), byref(block), c_int(flags))

    return rgba.raw