如何创建与原始数据串在Python

Question

magick棒的图像我有一个原始数据字符串，例如像这样：

raw_data = "FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF3300005CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFF9500B158DFFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFB200000003FFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFB100000002FFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFF643040B80FFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF3300002BFFED843913051B59D1FFFFFFFFFFFF03000184FFFF3300002BAB0F00000000000007BBFFFFFFFFFF03000057FFFF330000080100000000000000001DF8FFFFFFFF03000057FFFF330000000042A9D4D08D0D000000ADFFFFFFFF03000057FFFF330000059DFFFFFFFFFFAA00000070FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFA05000051FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF18000045FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF1B000043FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF1B000043FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF1B000043FFFFFFFF03000057" 

我想知道它是如何可能创造一个可视png格式出来的它。

我尝试使用Image class

with wand.image.Image (???) as img:

，但我不知道要放什么东西在括号中。我试过file=raw_data, width=25,height=25,depth=8

无论我尝试它给我一个错误。

任何想法？

Answer 1

您需要将字符串转换为字节，并实现ImageMagick的MagickImportImagePixels C-API方法。

import binascii 
import ctypes 

from wand.api import library 
from wand.image import Image 
from wand.color import Color 

# Map C-API to Python 
# ------------------- 
# magick-image.h 
# WandExport MagickBooleanType MagickImportImagePixels(MagickWand *wand, 
# const ssize_t x,const ssize_t y,const size_t columns,const size_t rows, 
# const char *map,const StorageType storage,const void *pixels) 
library.MagickImportImagePixels.argtypes = (ctypes.c_void_p, 
              ctypes.c_ssize_t, 
              ctypes.c_ssize_t, 
              ctypes.c_size_t, 
              ctypes.c_size_t, 
              ctypes.c_char_p, 
              ctypes.c_int, 
              ctypes.c_void_p) 


# Map enum StorageType 
StorageType = ('undefined', 'char', 'double', 'float', 
       'integer', 'long', 'quantum', 'short') 

# Extend wand.image.Image to implement import_pixels method 
class MyImage(Image): 
    def import_pixels(self, blob, pixel_format='RGBA', pixel_size='char'): 
     storage_type = StorageType.index(pixel_size) 
     library.MagickImportImagePixels(self.wand, 
             0, 
             0, 
             self.width, 
             self.height, 
             pixel_format.encode(), 
             storage_type, 
             blob) 
# Usage 
raw_data_string = 'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF3300005CFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFF9500B158DFFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFB200000003FFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFB100000002FFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFF643040B80FFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFFFF3300002BFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF3300002BFFED843913051B59D1FFFFFFFFFFFF03000184FFFF3300002BAB0F00000000000007BBFFFFFFFFFF03000057FFFF330000080100000000000000001DF8FFFFFFFF03000057FFFF330000000042A9D4D08D0D000000ADFFFFFFFF03000057FFFF330000059DFFFFFFFFFFAA00000070FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFA05000051FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF18000045FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF1B000043FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF1B000043FFFFFFFF03000057FFFF3300002BFFFFFFFFFFFFFF1B000043FFFFFFFF03000057' 
raw_data_bytes = binascii.unhexlify(raw_data_string) 

with MyImage(width=25, height=25, background=Color('WHITE')) as img: 
    img.import_pixels(raw_data_bytes, pixel_format='R', pixel_size='char') 
    img.save(filename='output.png') 

如在评论中指出，你将负责知道/定义通道布局（即RGBA，BGR，ARBG & TC），数据类型尺寸（即字符/ short/int/long或float/double），数据流布局（如interlacing），当然还有预期图像的实际宽度/高度。