6 Replies Latest reply on Dec 13, 2008 2:01 AM by Paul_LS

    AVCHD Editing 1920 vs 1440

    ruzun Level 1
      I've been having nothing but trouble with AVCHD clips in Adobe PRE7. I've finally tracked down what clips it can handle and which it can't. Any AVCHD that's 1440x1080, regardless of project settings, regardless of sound and sound settings, regardless of bitrate, is fine. Performance with AVCHD clips shot at 1440x1080 seems fine.

      Any clip shot in 1920x1080, slows PRE7 down to a crawl (usually). It becomes UNUSEABLE. You can import those AVCHD clips but you can't practically edit with them in the project, it simply can't render them and becomes a slideshow, again regardless of sound settings or bitrate or project settings.

      I have a quad core system, and on SOME projects, it will use all 4 cores to render the 1920 clips. Most projects it will not. When it does use all 4 cores to render it renders smoothly. I cannot for the life of me figure out how to "force" it to render using all 4 cores. Once I have a project saved that does this, it seems to always work, but I cannot figure out why it sometimes will only use 2 cores to render, and sometimes it will use all 4.

      The problem I have is with the Sony SR12, the max bitrate you can get with 1440x1080 clips is 9mbps. You get 16mbps with 1920x1080 clips. But it looks like I am forced into shooting 1440 whether i like it or not. It may not be so bad, I don't know how bad motion artifacting will be at that low bitrate with the SR12 at 1440 maybe it's ok, but 9mpbs seems low.

      I just wish PRE7 handled AVCHD clips that are 1920x1080 better. It seems it should, it handles avchd 1440 clips fine in any project.

      Seems like its a bug in the way it handles avchd that it would choke so hard on 1920 input, and perform so well with 1440 clips, from the same camcorder.
        • 1. Re: AVCHD Editing 1920 vs 1440
          Paul_LS Level 4
          Hi Roger, I dont know why you are having such problems with 1920x1080... I have used clips from a number of 1920x1080 AVCHD sources (SR10 same as SR12 but smaller hard drive, HF100)on my Quad Core and get smooth playback without rendering. Compared to 1440x1080 there is more processor usage but not a huge reduction in performance. Are you using the 1920x1080 project presets?
          • 2. Re: AVCHD Editing 1920 vs 1440
            ruzun Level 1
            I have used all project settings, and I have a sample clip from an SR10 as well and it also is very slow. It has to render it on playback, there is always a red line above the clips in the timeline since it doesn't handle AVCHD natively. I'm confused by your statement that you can load AVCHD files into PE7 and have it not render them, it renders all AVCHD clips regardless of project setting or resolution of the clip, unlike HDV which it can handle natively. I always see a red line above all my AVCHD clips in the timeline regardless of project settings or that clips resolution.

            Basically I do sometimes get smooth editing with 1920 clips but it seems almost random. If all 4 cores are utilized it plays back in the project smoothly, if not its a slide show. [edit] I found a way that appears to get all 4 cores in on timeline/sceneline rendering. If I bring up the windows task manager while its playing back the project, the 2 cores that were idle seem to kick in right away. I have no idea why they don't just kick in regardless, sometimes they do, sometimes they don't. I

            Perhaps some conflict with a codec pack is biting me? I'm tempted to get an old hard drive out, do a clean install on it, and see if it gets rid of the problem. It just doesn't want to use all 4 cores reliably unless I do the task manager thing.
            • 3. Re: AVCHD Editing 1920 vs 1440
              Paul_LS Level 4
              I see the red line but I do not need to render the clip to play bsck smoothly while editing it.
              • 4. Re: AVCHD Editing 1920 vs 1440
                Paul_LS Level 4
                Just a few more comments... when I playback 1920x1080 5.1 audio clips, without rendering, so with the red line above them, the processor usage is around 60%... ie all four cores running at 60%. When playing back 1440x1080 clips the processor usage is around 50%, so all four cores running at 50%. What I do notice is that sometimes when it plays from one clip to the next it will stutter for a few seconds (processor usage shoots to 80% and then down to 12% for a few seconds) before resuming normal playback. But this does not happen everytime.

                Note, when I render the clips, ie hit the Enter key, all four cores run at 100%.
                • 5. Re: AVCHD Editing 1920 vs 1440
                  ruzun Level 1
                  I'm running Vista Ultimate 32-bit, could that be screwing with things. I have an NVidia 260gtx (their newest higher end line, second from the current top of the line 280) video card with their latest drivers.

                  I'm almost tempted to get a new case, power supply, motherboard, cpu to just update things and start fresh without installing many 3rd party codecs etc.
                  • 6. Re: AVCHD Editing 1920 vs 1440
                    Paul_LS Level 4
                    Vista 32-bit should be fine with PE7. The video card is not critical for PE7 as it does not use any of the graphics card GPU power during editing/playback.