Detect Orientation of Video and auto rotate if needed

问题

I am looking to see if its possible to get the device orientation of a video to check and see if its needs to be rotated in PHP with ffmpeg.

Is this even possible? I have done it easy enough with images, but I have not found anything so far to help with this.

回答1:

Device orientation is a client side property, and PHP is strictly server-side. Quickly googling led me to this page, which has an example for the iPhone. The author offers this function, which is called on page load:

function updateOrientation(){  
    var contentType = "show_";  
    switch(window.orientation){  
        case 0:  
            contentType += "normal";  
            break;  

        case -90:  
            contentType += "right";  
            break;  

        case 90:  
            contentType += "left";  
            break;  

        case 180:  
            contentType += "flipped";  
            break;  
    }  
    document.getElementById("page_wrapper").setAttribute("class", contentType);  
}  

CSS is defined to handle styling for .show_normal, .show_right, .show_left and .show_flipped

.show_normal,  
.show_flipped{  
   width:320px;  
}  
.show_left,  
.show_right{  
    width:480px;  
}  

If you need the value for the orientation in PHP, you can send the value of window.orientation to a script via AJAX. There is also an event: window.onorientationchange that gets fired whenever the orientation changes. I believe both of those properties on the window are available for both iPhone and Android devices.

回答2:

exiftool -Rotation <filename>

来源：https://stackoverflow.com/questions/11000107/detect-orientation-of-video-and-auto-rotate-if-needed