C++ ofstream输出到图像文件在Windows上写入不同的数据

Question

我在做一件简单的事情:将存储为字符串的图像文件的数据写入包含该字符串的图像文件。

std::ofstream f("image.jpeg");
f << image_data; // image_data was created using python and copied over, in hex and turned back into ascii

然而，意想不到的事情发生了:

变成:

我不明白为什么会这样。

When I use python2.7 to get the data from the original picture and write it to a new file, it works fine.

When I compile and run my program in ubuntu, the picture comes out fine.

When I write a large text file (larger than the image) into a .txt, the file comes out fine.

It is only jpegs on Windows that fails. The original image I tried was an image from a PGP key packet, which came out with half of the person's head clear and the other half messed up.

编译后的程序并没有弄乱所有的数据，因为就像我上面说的，一些原始图片被显示出来了。此外，图片大小相同，因此至少保留了 jpeg 格式。

发生了什么事？我在 Windows 7 上的 Code::Blocks 中使用 ming2 4.7.2。Windows 是不是疯了？

Answer 1

您必须以二进制模式打开文件:

std::ofstream f("image.jpeg", std::ios::out | std::ios::binary);
//                                            ^^^^^^^^^^^^^^^^