Constructing a float32 value from four uint8 bytes

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I am trying to read depth values from the topic /camera/depth/image_rect_color. The message is of the type sensor_msgs/Image and prints out 8 bit data (uint8) as elements of an image array. Since the image is encoded as 32FC1, I need to combine four of these elements to obtain depth information of a single pixel. A stack overflow answer contains the following code:

float f;
uchar b[] = {b3, b2, b1, b0};
memcpy(&f, &b, sizeof(f));
return f;

Is this the right approach to construct a float32 value from 4 bytes of uint8 values, without any data loss ?