title: Why is my image's Bytes per Row more than its Bytes per Pixel times its Width?
body: <p>I'm converting images to a MOV file, and had an interesting thing happen to me.  I logged my bits per color component, bits per pixel, and bytes per row.  Here's my code:</p>
  
  <pre><code>NSLog(@"Image width: %d, Height: %d", CGImageGetWidth(image), CGImageGetHeight(image));
  NSLog(@"BPC: %d \ BPP: %d \ ByPR: %d", CGImageGetBitsPerComponent(image), CGImageGetBitsPerPixel(image), CGImageGetBytesPerRow(image));
  </code></pre>
  
  <p>Here's my output:</p>
  
  <p>Image Width: 300, Height: 300  (everything's as expected)
  BPC: 8   (8 bits per color...so far so good)
  BPP: 32  (32 = 4 components ARGB * 8 bits per color...got it)
  ByPR:1216  (300 px per row * 4 bytes per pixel = 1200 bytes per row)</p>
  
  <p>Why am I logged 1216 bytes per row, and not 1200?  By the way, this isn't just a fluke.  When I create a video based on those numbers for buffer sizes, it works.  When I create it with 1200 bytes per row, I get some messed up aliasing effect.</p>
  
  <p>Thoughts?!</p>