我有一个代表jpg的numpy数组,而不是文件。因此我必须直接处理数组。我想将这些数据保存到文件中,以便我可以使用常用的jpg查看器进行观看。通常我可以用
来做到这一点pl = pylab.imshow(ds.pixel_array, cmap=pylab.cm.bone)
但是图像信息是在jpg2000中编码的,因此这种方法失败了。我试过pgmagick:
tmp = pgmagick.Image(ds.pixel_array)
logging.info("Info I")
pl = pgmagick.Blob()
tmp.write(pl, 'GRAY')
但不幸的是,这也失败了,numpy-array无法转换为pgmagick-image的错误。有没有其他方法将jpg2000编码的信息转换为PIL-able信息?
更新:
运行以下行
jpg_bytes = ds.pixel_array.astype('uint8').tostring()
导致以下错误:
Data type not understood by NumPy: format='uint12', PixelRepresentation=0, BitsAllocated=12
编辑:完整的功能:
def convert(self, inputpic, outputpic = "", force = False):
if not inputpic or not os.path.isfile(inputpic):
logging.critical("No valid input filename entered, or input file not found. Input filename was " + inputpic)
return INT_ERROR
else:
input_clean = self.cleanEnding(inputpic)
if not outputpic:
outputpic = input_clean + ".jpg"
print "Output pic is " + outputpic
if os.path.isfile(outputpic + ".jpg") and force is False:
logging.critical("Output file is already there, don't want to overwrite it! Output filename was " + outputpic)
else:
if outputpic[:-4] is not ".jpg":
outputpic = outputpic + ".jpg"
try:
ds = dicom.read_file(inputpic, force=True)
except InvalidDicomError:
logging.critical("File " + inputpic + " is not a dicom file!")
return INT_ERROR
#try:
# pl = pylab.imshow(ds.pixel_array, cmap=pylab.cm.bone)
#except:
try:
logging.info("Decoding starts now")
jpg_bytes = "".join(chr(x) for x in ds.pixel_array)
logging.info("Test I")
jpg_bytes = ds.pixel_array.astype('uint8').tostring()
logging.warning("Trying to decode it with pgmagick")
im = pgmagick.Image.open(io.BytesIO(jpg_bytes))
logging.info("Decoding successfull")
#logging.info("Info I")
#pl = pgmagick.Blob()
#tmp.write(pl, 'GRAY')
except Exception as e:
logging.critical("Critical error happened during imshow() with file " + inputpic + " with the following error: " + str(e))
return INT_ERROR
if not os.path.isfile("tmp.png"):
pylab.savefig("tmp.png")
else:
logging.critical("tmp.png is already in this folder, maybe a failed cleanup? Stopping!")
return INT_ERROR
im = Image.open("tmp.png")
bg = Image.new("RGB", im.size, (255,255,255))
bg.paste(im, (0,0), im)
bg.save(outputpic[:-4], quality=95)
os.remove("tmp.png")
return INT_SUCCESS
使用inputpic作为dicom文件。
日志记录文件中的错误在第一个logging.info(logging.info("Decoding starts now")
)之后出现,因此我假设在第三行不再出现在日志文件中之后,从第二行抛出错误。
答案 0 :(得分:2)
假设pixel_array
是一个字节数组,表示JPEG编码的图像(如果是这种情况,则前四个字节 - 幻数 - 将为FF D8 FF E0
。)
您可以使用以下方法将numpy数组转换为字节字符串:
jpg_bytes = ds.pixel_array.astype('uint8').tostring()
您可以使用以下命令加载字节字符串:
import io
from pgmagick import Image
im = Image.open(io.BytesIO(jpg_bytes))
编辑:我错过了“jpg2000”位,所以:
0000 000C 6A50 2020 0D0A 870A
。