27 Replies Latest reply on Mar 8, 2011 8:00 PM by Colin Brougham

    Reversing AVCCAM footage

    shooternz Level 6

      Has anyone had any issues reversing AVVCAM ( AVCHD) footage in PPRO  CS5?

       

      Issue may just be in playback as I have not got round to exporting it out...but playback is still an issue anyway when a client wants to see the shot reversed while sitting  there!

        • 1. Re: Reversing AVCCAM footage
          Colin Brougham Level 6

          H.264/AVCHD footage was not designed for reverse playback. Rendering a preview is the only way around it. Maybe make a feature request for more heavy-duty on-the-fly rendering for reversed H.264?

          1 person found this helpful
          • 2. Re: Reversing AVCCAM footage
            shooternz Level 6

            Thanx for answer Colin ...dissapointing as it is.

             

            I often shoot stuff with a mind to reverse it.  Ho hum....

             

            I reversed the shot in AEFX and used an intermediate in the sequence.

             

            Guess I have another little adjustment to my workflow.

             

            "AVCHD - devil spawn"

            • 3. Re: Reversing AVCCAM footage
              Colin Brougham Level 6

              Heh... well, devil spawn or not, it's one of the quirks of dealing with this format. You don't have discrete frames as you would with DVCPROHD or AVCIntra, for example. Instead, you have a whole frame followed by a series of partial "predicted" frames. Since the encoders in these cameras are really only able to "look forward," the resulting video streams are encoded such that those whole frames are anchors and references for the frames to follow; when you play in reverse, you don't have a reference frame from which to construct the following (actually, preceding) frames. That's not to say that improvements couldn't be made to the decoding and playback components of Premiere, such that it could sort of "leapfrog" and cache whole and predicted frames to memory, and allow for smoother reversed playback--of course, that's just me talkin', and I ain't no engineer

               

              (Feature request!)

              • 4. Re: Reversing AVCCAM footage
                Bill Gehrke Most Valuable Participant

                Strange, I have recently reversed some AVCHD footage from my Sony HXR-NX5U and did not notice any problems with it.  When I get the editing computer back up again I will look at it.  I do not think I rendered the Timeline, I just played it and then encoded to MPEG2-DVD..

                • 5. Re: Reversing AVCCAM footage
                  the_wine_snob Level 9

                  Craig,

                   

                  Maybe the Feature Request will get you what you want and need? Worth a try.

                   

                  Good luck,

                   

                  Hunt

                  • 6. Re: Reversing AVCCAM footage
                    shooternz Level 6

                    I cant actually render the timeline ( I did try) ....but there is nothing to Render in my little CUDA MPE world!

                    • 7. Re: Reversing AVCCAM footage
                      Colin Brougham Level 6

                      I cant actually render the timeline ( I did try) ....but there is nothing to Render in my little CUDA MPE world!

                       

                      Hmm... if there is any sort of colored bar over the footage, you should be able to render. It's just a matter of using the correct render command: use "Render Effects in Work Area" to render only red bar/non-realtime sections, or use "Render Entire Work Area" to render both yellow and red bar sections. Even stuff that is playing back in realtime will be "force rendered" so that it will have preview files generated and associated with it.

                       

                      Doing something like reversing AVCCAM is sort of a sticky wicket because--especially with hardware MPE--Premiere thinks it can handle it, when the results clearly say otherwise. It is just playing back in reverse in the sequence (or Source Monitor) that should exhibit this issue; encoding to a destination of one sort or another will generate whole frames.

                      • 8. Re: Reversing AVCCAM footage
                        Colin Brougham Level 6

                        Strange, I have recently reversed some AVCHD footage from my Sony HXR-NX5U and did not notice any problems with it.  When I get the editing computer back up again I will look at it.  I do not think I rendered the Timeline, I just played it and then encoded to MPEG2-DVD..

                         

                        I'd be interested to hear what you find with this. I only have tested/worked with Canon T2i and 7D footage (H.264 MOVs) and Panasonic HMC150 (AVCHD MTS) and found the poor reverse playback with both of them. It's possible the NX5U stream is a little different and is more capable of reverse playback. I'm downloading a 720p sample clip right now and will experiment with it.

                        • 9. Re: Reversing AVCCAM footage
                          Jim_Simon Level 8

                          Oh, for an affordable, hand-held AVC-I camera...

                          • 10. Re: Reversing AVCCAM footage
                            shooternz Level 6

                            AVC-I would sort it. No doubt.

                             

                            Rendering.  Yes.  I tried all manner of things to try and render that section /clip but PPRO wont render what it doesnt think it has to.

                             

                            As I said ..I did it in AEFX. and created an intermediate but next time ... I will do a test whereby I will transcode the clip to DNxHD  and reverse that in the TL.

                             

                            I presume that will work and be  another simpler solution.

                             

                            I have submitted a feature request.

                            • 11. Re: Reversing AVCCAM footage
                              Jeff Bellune Adobe Community Professional

                              I just rendered a reversed NX5U clip and it's as smooth as silk.

                               

                              -Jeff

                              • 12. Re: Reversing AVCCAM footage
                                shooternz Level 6

                                How did you render it Jeff...and did it playback smoothly in the timeline prior "rendering" ??

                                 

                                When I apply reverse to the clip...the color bar doesnt change at all. Nothing to render according to PPRO.. so it does nothing.

                                • 13. Re: Reversing AVCCAM footage
                                  Bill Gehrke Most Valuable Participant

                                  Here is my NX5U clip in the tumeline and as you said it does not require rendering.  I took a look at the Preview folder and it was empty.  It plays smooth as silk.  This is recorded at 24 Mbps, what is your record rate?

                                   

                                  Reverse-play.jpg

                                  • 14. Re: Reversing AVCCAM footage
                                    shooternz Level 6

                                    My record rate is the same as yours Bill.

                                     

                                    I am going to try some of the other clips and also see if my isue is related to VFR .  We shot some clips at a variable frame rate.

                                     

                                    At least I am getting confirmation that avchd can be reversed  and plays back smoothly in the timeline.

                                     

                                    Now to find out why I cant!

                                    • 15. Re: Reversing AVCCAM footage
                                      Jeff Bellune Adobe Community Professional

                                      Prior to rendering, I had a yellow bar and the footage was dropping a lot of frames playing backwards.  Using Sequence | Render Entire Work Area, I got the clip to render.

                                       

                                      -Jeff

                                      • 16. Re: Reversing AVCCAM footage
                                        Colin Brougham Level 6

                                        Craig,

                                         

                                        Did you read what I said about using the "Render Entire Work Area" command? That will force a render of even yellow bar sections.

                                         

                                        I did a quick test on my workstation: HMC150 and NX5U clips play back in reverse (either clip reversed or just playing in reverse) smoothly for a few seconds, and then start to jump and stutter. CPU utilization is higher in reverse; I'm running an i7-930 OC'ed at 4.0GHz and 24GB of RAM. It's definitely not smooth, but workable.

                                         

                                        Playing in reverse or speed reversing an Canon 7D clip or some random AVCHD from (I think) a Panasonic TM700 just falls to pieces. Both show yellow bars, and force rendering works fine.

                                         

                                        At least I am getting confirmation that avchd can be reversed  and plays back smoothly in the timeline.

                                         

                                        Yes, if you pre-render it or have a monster CPU like Bill does; I wouldn't expect you to find much joy unless you really overcrank your CPU, or replace it all together. Decoding H.264 is a CPU-heavy task; throwing the car in reverse makes that even more difficult.

                                        • 17. Re: Reversing AVCCAM footage
                                          shooternz Level 6
                                          Did you read what I said about using the "Render Entire Work Area" command? That will force a render of even yellow bar sections

                                           

                                          Yep...absolutely did try that.

                                           

                                          My experience is exactly the sme as you described.

                                           

                                          CTI hesitates a little...plays foward o.k...then stutters and buggers around.  Not cool or wsorkeable.

                                           

                                          Anyway ..for now..I have the DNxHD intermediate  work around so I am not too sweated.

                                          • 18. Re: Reversing AVCCAM footage
                                            Colin Brougham Level 6

                                            Yep...absolutely did try that.

                                             

                                            So, did it work or no?

                                             

                                            Anyway ..for now..I have the DNxHD intermediate  work around so I am not too sweated.

                                             

                                            That's what I'd do, though there is probably no need to go to AE. Just drop the clip in its own sequence (even drop it on the New Item button), reverse it, and export from Premiere to whatever DI you want to use (DNxHD is fine). That way, you're not hopping between programs, and you can queue 'em up to AME in the background if you have a few to process.

                                            • 19. Re: Reversing AVCCAM footage
                                              shooternz Level 6

                                              Nothing worked to get an avchd file reversed and playing back smoothly on the time line.

                                               

                                               

                                              DNxHD...heres how I work it if I need an intermediate.

                                               

                                              I simply drag the source file(s) (.mts) directly into AME and select my custom DNxHD preset , export or queue and bingo.

                                               

                                              It works great and is as fast as all get out.

                                              • 20. Re: Reversing AVCCAM footage
                                                Bill Gehrke Most Valuable Participant

                                                My clip is only three plus seconds long.  Later I will try a longer clip.

                                                • 21. Re: Reversing AVCCAM footage
                                                  Colin Brougham Level 6

                                                  Nothing worked to get an avchd file reversed and playing back smoothly on the time line.

                                                   

                                                  That's weird; something is wrong with your install if you can't force a render of yellow bar sections.

                                                   

                                                  I simply drag the source file(s) (.mts) directly into AME and select my custom DNxHD preset , export or queue and bingo.

                                                   

                                                  Oh. Sheesh. Silly me That's much easier

                                                  • 22. Re: Reversing AVCCAM footage
                                                    Colin Brougham Level 6

                                                    My clip is only three plus seconds long.  Later I will try a longer clip.

                                                     

                                                    I could get about 3-5 seconds of smooth playback before things started to breakdown. I suspect that CS5 isn't capable of rendering and caching enough frames on-the-fly to maintain smooth playback in reverse with this sort of material.

                                                     

                                                    It's interesting; if you open up Task Manager to the Performance tab, you can watch the CPU utilization climb for a few moments before playback, and then suddenly drop to almost nothing just before the end of the clip. Even on my workstation, that spool up period takes longer when playing a clip in reverse.

                                                    • 23. Re: Reversing AVCCAM footage
                                                      Bill Gehrke Most Valuable Participant

                                                      Gentlemen, you are correct in that Premiere CS5 is not capabile of playing back a lenghty AVCHD reversed clip without rendering. I guess my first short (3 second) clip was about the maximum.  I just pulled up a 3+ minute clip, got rid of the audio, reversed it and definitely had problems with yellow playback.  Here is what the Resource Monitor looked like:

                                                       

                                                      Resource-Monitor.jpg

                                                       

                                                       

                                                      After I rendered the Work Area, I got the green bar and as Jeff said, then it played beautifully.  Notice one thing from above, the CPU usage was only about 50 % on my hex core CPU.  Apparently the coding could be optimized to make this CPU intensive process more efficient.  Disk usage was very low.

                                                       

                                                      Message was edited by: Bill Gehrke

                                                      1 person found this helpful
                                                      • 24. Re: Reversing AVCCAM footage
                                                        shooternz Level 6

                                                        Devil Spawn.....CONFIRMED by Bill.

                                                         

                                                        Wonder why I cant render it?

                                                         

                                                         

                                                        • 25. Re: Reversing AVCCAM footage
                                                          Colin Brougham Level 6

                                                          Wonder why I cant render it?

                                                           

                                                          Stupid question time: you've got the section marked off with the work area bar, right?

                                                          • 26. Re: Reversing AVCCAM footage
                                                            shooternz Level 6

                                                            Hell yeah.

                                                             

                                                            I have gotten so used to not rendering stuff .... that I have forgotten what it looks like when it happens!

                                                             

                                                            EDIT

                                                             

                                                            I am such a *******. I have got it sorted and working now.

                                                             

                                                            Dont know if I can even make this confession ...the shame of it......

                                                             

                                                             

                                                             

                                                            oh well....here goes...for the greater good of the forum.. and other klutzes like me

                                                             

                                                            I was rendering by ENTER key and also by Render Effects in Work Area (from the menu)  and the WAB was covering the section.

                                                             

                                                            I totally ignored 'Render Entire Work Area'  despite CB  and Jeff B telling me to do exactly that.

                                                             

                                                            DOH...doh...doh........!

                                                             

                                                            slinks away , quietly closing the door behind himself.

                                                            • 27. Re: Reversing AVCCAM footage
                                                              Colin Brougham Level 6

                                                              It's cool, man... it's cool.

                                                               

                                                              ...

                                                               

                                                              BWA HA HA HA HA HA!

                                                               

                                                              ...

                                                               

                                                              *wipes tear*

                                                               

                                                              Phew, needed that

                                                               

                                                              Aaaaanyway, glad you're cooking now. And really, make a feature request for better performance in reverse (and forward, for that matter) with AVCHD. It's not going away any time soon.