<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; color: rgb(0, 0, 0); font-size: 14px; font-family: Calibri, sans-serif; "><div>Hi,</div><div><br></div><div>I want to encode a synthetically sequence of images into an H.264 video with as little CPU as possible. By synthetically generated I mean that my program is generating the images – so I already know a number of characteristics of each frame. For example I know which parts of each frame differ from the previous frame – i.e. the rectangle containing the pixels that have changed from the previous frame.</div><div><br></div><div>I am trying to work out if there is a way to tell x264 that only pixels within a certain rectangle have changed when encoding each frame. It seems to me that if I could do this then a lot of computation could be saved because it wouldn't be necessary to do anything related to motion estimation. Basically the first frame in my video would be an I-frame and then every subsequent frame would be a P-frame containing only the pixels in the changed rectangle.</div><div><br></div><div>I am more concerned about reducing the CPU overhead than the size of the resulting file.</div><div><br></div><div>Can anyone give me any hints on where to look in the x264 source code to do something like this?</div><div><br></div><div>Thanks,</div><div><br></div><div>Chris.</div></body></html>