uyvy with alpha at half res?

    Jun 21 2013 | 2:17 pm
    hi, just wondering: does anything as "uyvya" exist? like uyvy with an alpha channel at half the resolution? or maybe even something like uyvyaa with the alpha at full res?
    best karl

    • Jun 21 2013 | 6:35 pm
      no alpha with uyvy. check out the hap-alpha option for the hap quicktime codec, and the external.
    • Jun 21 2013 | 10:24 pm
      thanks for your quick reply! hap is cool but unfortunately no option in my case since i work with frame sequences saved as .jxf-files.
      i did however fiddle around with this a little in the meantime and at least in my case this actually does help: i write my clips in an uyvya-fashion to disk (beforehand) and then unpack/pack them into uyvy + alpha when reading. the performance boost is not huge but quite noticable - i guess disk speed is the bottleneck in my setup. with 720p video a single argb-jxf is 3,7 mb vs. 2,3 mb employing this approach. the fact that the alpha channel is only half the resolution is - at least in my setup - not noticable. k