36 Replies Latest reply on Jul 15, 2009 7:12 AM by the_wine_snob

    Audio of an HD video is choppy

    EckleySP Level 1

      I've just started importing clips from a Panasonic AG-HMC150 into PE7 - got a new, very fast machine to do so.  It has the new Intel Core i7 CPU 965 running with 3 GB of RAM.   The video is smooth as silk, but the audio starts to play (for a second) then falls silent.  If I stop and start playing the clip, same thing - begins to play then falls silent again.   I have an M-Audio FW410 Audio Interface.  All works fine on old clips that are standard format (not HD).  Note the issue is with editing the clips, not the final rendered product.

       

      Any ideas?

        • 1. Re: Audio of an HD video is choppy
          Paul_LS Level 4

          Nice camcorder and nice computer. It seems strange that it starts to play them and then stops... and that it plays your old clips OK. What audio format are your new AVCHD clips?

          • 2. Re: Audio of an HD video is choppy
            EckleySP Level 1

            I'm not sure of the audio format.  How do I find out?   And, I agree, with this much power and speed - especially with the video being so smooth, I don't understand why I'm getting the dropouts on the audio.   Got to be something in configuration... 

             

            S

            • 3. Re: Audio of an HD video is choppy
              Paul_LS Level 4

              I looked at a review of the camcorder and it says it only supports Dolby AC3 audio which is a supported format for PE7... so I dont really know what is going on.

               

              When you import the clip does it say Conforming audio down in the bottom right of the screen? If so make sure to leave it to complete. One thing to try, with the clip on the timeline, click on it to highlight it then select Clip from the taskbar at the top of the screen, then Audio Options, then Render and Replace. This will replace you audio with a .wav file.

              • 4. Re: Audio of an HD video is choppy
                EckleySP Level 1

                Useful suggestion, (turning audio to WAV files) but the result is the same.  The FW 410 allows you to change buffer sizes - which I've changed up and down the scale - to no avail.   It sounds like a drop-out (something you would expect from a Music Sequencer like Sonar).   In the case of Sonar, it's sometimes a latency.

                 

                Sonar (which I use - I write music too) says:

                 

                ... these audio problems are the result of audio information not being sent to or received from your sound card fast enough or reliably enough. During recording, the sound card sends incoming audio data to the sound card driver, which in turn sends audio data to SONAR to store on hard disk. When playing back, SONAR reads audio data from the hard disk and feeds it to the sound card driver, which in turn passes it to the sound card for audible output. If these activities can't be completed fast enough, or if the communication between SONAR and the sound card driver is broken in some way, recording and/or playback will be disturbed.

                 

                My audio is definately disturbed.  Just don't know why.

                 

                I also moved things around (scratch files) - but in reading about this, it sounds like some changes really doesn't go into effect immediately.   I tired adding a new video to the project to see if the new placement of scratch files would help - it didn't.

                 

                Btw, when I do load a clip, it does conform - blazing speed.  I'm really happy with everything but the audio, and I'm still convinenced that there's something that needs to be tweaked...

                • 5. Re: Audio of an HD video is choppy
                  Paul_LS Level 4

                  Have you made sure your audio drivers are up to date?

                   

                  Also check you ASIO settings under Edit -> Preferences -> Audio Hardware -> ASIO Settings... what is enabled at the top of the list? I suspect your problem may lay in these audio settings as you have a dedicated sound card.

                  • 6. Re: Audio of an HD video is choppy
                    the_wine_snob Level 9

                    Along these lines, one's I/O system (HDD's and controller) can cause problems due to data transfer rates. How are the HDD's on your computer setup and utilized for editing? Do you have any of your HDD's partitioned?

                     

                    If Paul's suggestions for the ASIO settings do not clear this up, next investigate your I/O setup for any bottlenecks. Also, as Paul suggests, make sure to let PE finish creating the CFA and PEK files for your audio.

                     

                    Good luck,

                     

                    Hunt

                    • 7. Re: Audio of an HD video is choppy
                      EckleySP Level 1

                      Under Audio (preferences), both boxes are checked.

                       

                      Play audio while scrubbing and Minimum Time Interval Thinning is set at 20 milliseconds.

                       

                      The FW 410 is selected on the Audio Hardware tab.  Audio Output Mapping looks OK.

                       

                      Under Project Settings (General), the sample rate is 48000 Hz and can't be changed - this matches that set on the audio interface (FW410), so as far as the obvious settings go, things look 'normal'.

                      • 8. Re: Audio of an HD video is choppy
                        EckleySP Level 1

                        I'm not sure how to setup the hard drives for 'editing' - or to optimpize them.   The video files themselves are stored on a 1 TB internal drive.  The application files are stored on an internal 320 GB drive (OS is on the C drive).   I have another 500 GB internal that I use for 'rendering'.   All are setup to "Enable Write Caching".

                         

                        None are partitioned that I know of.  That's about the extent of my gray matter on hard drives.

                         

                        Scott

                        • 9. Re: Audio of an HD video is choppy
                          EckleySP Level 1

                          I think before doing much more, I'm going to check for updates for the FW410.  I think I'm using the most current driver, but not sure.  I'll check firmware as well - but the M-Audio website is down at the moment.

                           

                          Think I'll go hit golf balls for a while...

                           

                          that always helps,

                           

                          S

                          • 10. Re: Audio of an HD video is choppy
                            Paul_LS Level 4

                            I dont know if you have an onboard sound card but you could temporarily revert to that to see if PE7 audio then works... it would then show a set up issue with your sound card.

                             

                            Also what outputs are enabled in the ASIO settings and what is at the top of the list?

                            • 11. Re: Audio of an HD video is choppy
                              the_wine_snob Level 9

                              It looks like you have a good I/O setup:

                              C:\ OS and programs

                              D:\ Media

                              E:\ Rendered material

                               

                              (Drive letters could be different on your exact system, but it points to 3 physical HDD's, which is a good thing and the setup is a good one)

                               

                              Unless your "media drive" is via a very slow connection (or of a slow speed), things should be fine from that end.

                               

                              I think we can rule this out, as your problem.

                               

                              Now, let's hope that Paul is zeroing in on the problem via drivers.

                               

                              I'll keep thinking. Good luck.

                               

                              Hunt

                              • 12. Re: Audio of an HD video is choppy
                                windowman Level 1

                                This FW device has always been problematic. It's a $400 paper weight.

                                • 13. Re: Audio of an HD video is choppy
                                  EckleySP Level 1

                                  OK.  Spent an hour hitting balls and making putts.

                                   

                                  I disabled the FW410 and enabled the on-broard soundcard.  Then held my breath.

                                   

                                  Same result (good thing, I think).

                                   

                                  And, I do have the latest driver.

                                   

                                  Since I get the same condition with the other soundcard, I guess I can assume the issue is not with the FW410.

                                   

                                  I'm running out of options.

                                  • 14. Re: Audio of an HD video is choppy
                                    Paul_LS Level 4

                                    I still think it is your Asio settings/Output mapping, but I dont know how they would be set up for a soundcard. When you go to Edit>Preferences>Audio Hardware>ASIO Settings. What is enabled in the top list... it should be Speakers. If not try deselecting the other options and select Speakers.

                                    • 15. Re: Audio of an HD video is choppy
                                      windowman Level 1

                                      A couple of things:

                                       

                                      First off 3-gigs of ram isn't really very much for editing AVCHD. Several NLE venders are recommending as much as 8.

                                       

                                      Second, is this a dedicated computer for NLE work? I doubt it or you'd be using a more expensive NLE program. At any rate, I would go into Windows "Sounds" and disable all Windows sounds. This will stop things like those goofy bells whenever a program finishes rendering and that sort of thing. A lot of times those sounds are only 8-bit and will often be a different resolution than the one you're editing at, so suddenly your soundcard has switched to a different bit depth or resolution without your telling it to. If you soundcard has an option to "lock the sample rate" then I would make use of that while working with audio or video programs.

                                       

                                      Third, make sure Windows manages your virtual memory. If you've set it yourself, then when you need more page file you may not be able to get what the NLE needs, whereas if you let Windows manage it for you it'll take whatever it wants and this is better for working with video. (It's not like the old days with Windows 98 when we set it ourselves).

                                       

                                      Fourth, try separating the audio from the video in Premiere and placing the audio on a different track. Also try deleting the video from the timeline and playing the audio by itself to see if it plays okay without the video.

                                       

                                      Fifth, if nothing else works you can always convert the AVCHD material to something else before working with it. It's a pain, but you may have to.

                                      • 16. Re: Audio of an HD video is choppy
                                        EckleySP Level 1

                                        When I select ASIO Settings, it simply opens the FW410 Control Panal.

                                         

                                        The mixer, output settings must be 'correct', otherwise I would hear anything... right?

                                         

                                        Just one other clue - when I:  Clip/Audio Options/Render and Replace...  the WAV file appears in my project 'list' with the video file(s).   When I double click on the WAV item, it opens in a Audio Preview dialog box and plays - very happily - just fine.

                                         

                                        So, it would appear to be a resource issue - since the issue occurs when the video is also playing...  you agree?

                                         

                                         

                                        And, I've had the FW410 for years - so I didn't pay 400.00 USD, but I'm wondering if another 'card' might not fix the whole problem.

                                         

                                        Scott

                                        • 17. Re: Audio of an HD video is choppy
                                          windowman Level 1

                                          Well you already tried the mobo soundcard and got the same result so I doubt the soundcard is causing the problem. That you can play the sound file correctly the way you did just now without the video tells us its a software issue or possibly a memory issue. Have you monitored system resources while playing? Try bringing up Task Manager and watching the performance tab for your CPU and page file usage while playing the video from the timeline. My best guess is that your box is simply running out of steam.

                                          • 18. Re: Audio of an HD video is choppy
                                            EckleySP Level 1

                                            Agreed, but I need a paper weight.

                                             

                                             

                                            CPU Usage while playing the clip stays under 20 percent about 99 percent of the time.  The PF Usage varies between 1.6 and 1.7 GB.

                                             

                                            There is other data -

                                             

                                            Commit Charge (Peak is 1841812),

                                            Kernel Memory (Paged is 59800; nonpaged is 14568),

                                            Physical Memory (System Cache 1528056, Available 1432292)

                                             

                                            No idea what these numbers mean, except the CPU Usage of 20 percent, sounds great.

                                            • 19. Re: Audio of an HD video is choppy
                                              EckleySP Level 1

                                              On this note:

                                               

                                              First off 3-gigs of ram isn't really very much for editing AVCHD. Several NLE venders are recommending as much as 8.

                                               

                                              Here's the 64 thousand dollar question.  I'm running WIndows XP (SP3).  A 32 bit O/S.  So how much RAM can it actually use?

                                               

                                               

                                               

                                              Second, is this a dedicated computer for NLE work? I doubt it or you'd be using a more expensive NLE program. At any rate, I would go into Windows "Sounds" and disable all Windows sounds.

                                               

                                              I've donet this - it's a requirement of not only PE3 but Cakewalk's Sonar - I write music too, so no - don't want any whoops or bells interferring with my stuff.

                                               

                                              If you soundcard has an option to "lock the sample rate" then I would make use of that while working with audio or video programs.

                                               

                                              Don't see an option for this.

                                               

                                               

                                              Third, make sure Windows manages your virtual memory. If you've set it yourself, then when you need more page file you may not be able to get what the NLE needs, whereas if you let Windows manage it for you it'll take whatever it wants and this is better for working with video. (It's not like the old days with Windows 98 when we set it ourselves).

                                               

                                              I've not touched this - so I hope Windows is managing this.

                                               

                                               

                                              Fourth, try separating the audio from the video in Premiere and placing the audio on a different track. Also try deleting the video from the timeline and playing the audio by itself to see if it plays okay without the video.

                                               

                                              Interesting - when I unlink the Video/Audio, and delete the Video, the audio sounds fine; no skips or dropouts.  Simply moving the audio to another track doesn't help (when played with the video).

                                               

                                               

                                               

                                               

                                              Fifth, if nothing else works you can always convert the AVCHD material to something else before working with it. It's a pain, but you may have to.

                                               

                                              The video camera can record in the formats of:  1080/60i;

                                                                                                                   1086030i

                                                                                                                   1080/24i

                                                                                                                   720/60i

                                                                                                                   720/30i

                                                                                                                   720/24i

                                               

                                              I can change it to record at 1080/30i...  you think that would make a difference?

                                              • 20. Re: Audio of an HD video is choppy
                                                EckleySP Level 1

                                                Also - what's an NLE?

                                                • 21. Re: Audio of an HD video is choppy
                                                  windowman Level 1

                                                  It looks like you're doing okay in the horsepower department (keeping in mind that you aren't running any effects yet), and 3-gigs is the RAM limit with your system.

                                                   

                                                  NLE - non-linear editing i.e. a computer rather than a tape based editor. Premiere, Final Cut Pro, Avid, Vegas etc. are all non-linear editing systems. So when someone asks what NLE you're using they simply want to know what video editing program you have.

                                                   

                                                  Your page file is probably fine if you've never touched it.

                                                   

                                                  When I say you might need to convert the clips I mean to something like HDV. I don't use HDV for anything, but by all accounts here it works very well with Premiere Elements. The best tool for the conversion I'm aware of is canopus procoder 3, but it's expensive. Elecard Converter is a little cheaper. AVCHD UpShift is yet another. Maybe someone here knows of a free converter.

                                                   

                                                  Another format that would be better to convert to would be DVCPro HD. I don't know any converters that do it, but I don't use it myself. There's probably someone else here that can give you a few names.

                                                  • 22. Re: Audio of an HD video is choppy
                                                    EckleySP Level 1

                                                    Thanks for all the help.  I'll continue the tweaking and see if I have the same issue with the other formats recorded with the same camera.  If I stumble (and I mean that literally) on anything good, I'll post it here...

                                                     

                                                    Scott

                                                    • 23. Re: Audio of an HD video is choppy
                                                      the_wine_snob Level 9

                                                      Sorry. NLE is (NonLinear Editor, like Premiere, or Vegas or Final Cut Pro [FCP]). Sometimes I get carried away with the jargon, and forget that everyone doesn't speak the same language, as I do. I also have to remember that I am from Mississippi, where English is a second language! [Grin] Fortunately, that does not come into play on the Adobe fora, but you should see the puzzled looks on Chowhound.

                                                       

                                                      Hunt

                                                      • 24. Re: Audio of an HD video is choppy
                                                        the_wine_snob Level 9

                                                        In your case, XP-Pro, 3-4 GB of RAM is about as good as it gets. I am also a fan of setting a static Page File (Windows Virtual Memory), and use 2.5 - 3x the physical RAM. In my case, the Page File is 12GB, and is spread over two physical HDD's (this took experimentation, and is different on my NLE workstation, than it is on my laptop). Yes, it's overkill for much of the work, but then I have many extra TB's of HDD space, so I do not mind having more than is necessary for many operations, so long as I have it, when needed.

                                                         

                                                        One thing that we've not talked of is other programs and Processes, that might be running and taking CPU cycles. Since you edit Audio, I'd guess that you keep the loaded programs and running Processes to a minimum, i.e. shutting down AV, anti-spyware and pop-up blockers. How about the running Processes? Take a look at the Processes in Task Manager. You might be surprised. I use EndItAll2 to eliminate all of the unnecessary ones, when doing NLE work.

                                                         

                                                        One last thought. If this is an ASIO issue (does not sound like it is), you might try ASIO4All. Just install it, and then set the Preferences for PE to point to it, as it will appear in the list of ASIO choices. Might be worth a try.

                                                         

                                                        Otherwise, I don't have any other ideas, but will add any that pop into the feeble mind.

                                                         

                                                        Good luck,

                                                         

                                                        Hunt

                                                        • 25. Re: Audio of an HD video is choppy
                                                          Paul_LS Level 4

                                                          OK, hit the Enter key on your keyboard to render the clip and then see if the audio plays back smoothly. I wonder if it is as simple as this. You say when you unlink the video/audio and delete the video the audio plays back with no skips or jumps. I thought from your initial description that the audio played for a few seconds and then stopped. If you are getting skipping/jumping it sounds more like you just need to render the video.

                                                           

                                                          Although with an i7 processor I should of thought you had enough horesepower to play the video without rendering.

                                                          • 26. Re: Audio of an HD video is choppy
                                                            EckleySP Level 1

                                                            Yes, somewhere in this thread, I think I mentioned this is only an issue when editing the clip(s).  If I render it to a DVD or file, it sounds fine.   Given the choice between having choppy sound and good video, and choppy video and good sound, I'll take the former.  Still, I paid some cash to have this system built (custom), so it not performing to it's peak ability does not make me happy.

                                                             

                                                            I suppose I could go the whole 64 bit route.  PE7 I don't think will run in that environment - so there's even more money to be laid out for another app.

                                                            • 27. Re: Audio of an HD video is choppy
                                                              Paul_LS Level 4

                                                              When I say render i do not mean exporting the clip. To play a "non-native" clip (as in your case AVCHD is not edited natively in PE7) back in PE7 you need to hit the Enter key to render the clip for playback from the timeline. Did you try this?

                                                              • 28. Re: Audio of an HD video is choppy
                                                                EckleySP Level 1

                                                                (OK, I'll need to read up on this).

                                                                 

                                                                The short story is that that worked.

                                                                 

                                                                It would seem (after a little experimentation) that what I hear after rendering is a separate file that is created and, that if I apply effects afterward, I'm back to hearing the clip again - edited, not rendered.  After applying the effects, I can render it again.  (etc.)

                                                                 

                                                                I've been using this software for a year and didn't know about this feature.  Until now, I guess I didn't need it.

                                                                 

                                                                Still, I assume with large projects, if you render the clips you are happy with, and edit those that need work, the software and user get along better and each is 'happier'.  Is that the idea?  

                                                                • 29. Re: Audio of an HD video is choppy
                                                                  windowman Level 1

                                                                  "It would seem (after a little experimentation) that what I hear after rendering is a separate file that is created and, that if I apply effects afterward, I'm back to hearing the clip again - edited, not rendered.  After applying the effects, I can render it again."

                                                                   

                                                                  By Jove he's got it!

                                                                  • 30. Re: Audio of an HD video is choppy
                                                                    Paul_LS Level 4

                                                                    Yes, once you add any effects, transitions or titles to a clip then it will need to be re-rendered.

                                                                     

                                                                    Glad we got to the bottom of it.

                                                                    • 31. Re: Audio of an HD video is choppy
                                                                      EckleySP Level 1

                                                                      "He can be taught!"

                                                                       

                                                                      Again, thanks for all the insight.

                                                                      • 32. Re: Audio of an HD video is choppy
                                                                        the_wine_snob Level 9

                                                                        Great! The key phrase in Paul's comment is "non native... " Everything, that is not DV-AVI Type II and 48KHz 16-bit Audio needs to be Rendered to play properly. With very traditional Audio source files, like 44.1KHz 16-bit, that is what the CFA file (Conformed Audio) is for - it's basically a "render" to 48KHz 16-bit. (The PEK file is the Waveform Display file, to allow one to see the Waveform.) With non-traditional Audio, the Render (Enter key) takes care of this, as both the Video (if needed) and the Audio are Rendered to conform to DV-AVI Type II and 48KHz 16-bit Audio. One can accomplish the same thing with the Audio file(s) with Render/Replace, which converts to a PCM/WAV 48KHz 16-bit file. Pretty much the same with a Video file. However, as Paul states, any change will require re-Rendering. These changes could be a Color Correction, a Luma correction, a Title (that is super-imposed on the Video), a PiP (Picture in Picture) Clip added, a Transition, etc. These change what is viewed, and need to be accounted for with a Render.

                                                                         

                                                                        Now, Rendering is not necessary for perfect output - just perfect (or near perfect) monitoring. Normally, I do not Render, unless I've got a.) non-traditional footage, or b.) really need to see, as perfectly as is possible, an Effect. When doing a lot of Effects experimentation, I'll position the WAB (Work Area Bar) over that Clip(s) and Render each change, so I can study how the Effect looks. I might Render that section 20 times, as I explore various Effects and settings, until I am satisfied with the results. If I'm just doing Cross-Dissolves (other than checking for proper Handles), I'll leave the file un-Rendered.

                                                                         

                                                                        Thanks for hanging in there, and also reporting back with your success. Your question/problem will likely help many others down the line. Many countless hundreds of folk drop in with a problem, search the forum a bit, find their answer and head off to continue editing. We never even know that they are here, but it's threads, like your's, that help them find the answers to their problems.

                                                                         

                                                                        Hunt

                                                                        • 33. Re: Audio of an HD video is choppy
                                                                          EckleySP Level 1

                                                                          Hunt.  What in the world do you do for a living....  ?

                                                                           

                                                                           

                                                                           

                                                                          Having said (all) that... (1)  I expect perfection.  I expect with this machine and this software - which I believe advertises compatability with these files - it should play the audio seamlessly with the video.  And, (2) On a good day, I hear 75-80 percent of the audio - meaning about 30 percent drops out.  (On a bad day, 50 percent)  That's enough to determine where to cut, insert, apply an effect - whatever.  So, it's not an issue of usability, it's one of not meeting expectations.

                                                                           

                                                                          And with all meaningful journeys, it is not the end that matters but what is learned and created along the way.

                                                                          • 34. Re: Audio of an HD video is choppy
                                                                            Paul_LS Level 4

                                                                            I agree, with your processing power you should be able to play AVCHD files without audio drop outs even without rendering. Maybe after adding effects, color-correction you would need to render... but not clips just placed on the timeline. I do not see these issues with my Quad Core 2.4GHz processor. However I use the machine exclusively for editing... so no anti-virus, no internet... nothing running in the background.

                                                                            • 35. Re: Audio of an HD video is choppy
                                                                              EckleySP Level 1

                                                                              OK -

                                                                               

                                                                              When you initially create a project, you (apparently) have to say what format the clips are in.  I didn't do that, so I've been importing 1920x1080 clips into a 'standard' (format) project.   That's a problem.  When I create a project with the same specifications (1920 x 1080) as the clips I'm importing, the problem seems to be resolved...

                                                                               

                                                                              Just an FYI.

                                                                              • 36. Re: Audio of an HD video is choppy
                                                                                the_wine_snob Level 9
                                                                                When you initially create a project, you (apparently) have to say what format the clips are in.

                                                                                 

                                                                                That is the correct way to do it. The Project settings match the specs. of the Imported footage. In Export/Share, one sets the output specs.

                                                                                 

                                                                                Good luck,

                                                                                 

                                                                                Hunt