Hello everyone,
We know from previous posts (https://feedback.techsmith.com/techsmith/topics/problems_with_48_khz_audio) that 48 kHz audio is not supported in Camtasia 8.x. For our company, we use capture technology that can only out put 48 kHz quality. When I saw Camtasia 9 release, I was very hopeful to see something about support on 48 kHz. Our company is looking for justification on the upgrade to Camtasia 9, and full 48k support would be a huge part of that.
I was very excited to pull in some 48 kHz audio (.mp4 files with 1080p video and 48k audio) and hear it play back OK on the timeline! AND even though the project produced at 44.1 kHz, it sounds great. Unfortunately, the audio-video sync drifts when I produce a few of these test .mp4 files -- leading me to think full 48k support is not here yet.
Bottom line question, can someone from TS fill us in on what enhancements were made with respect to 48 kHz audio in v9?
We know from previous posts (https://feedback.techsmith.com/techsmith/topics/problems_with_48_khz_audio) that 48 kHz audio is not supported in Camtasia 8.x. For our company, we use capture technology that can only out put 48 kHz quality. When I saw Camtasia 9 release, I was very hopeful to see something about support on 48 kHz. Our company is looking for justification on the upgrade to Camtasia 9, and full 48k support would be a huge part of that.
I was very excited to pull in some 48 kHz audio (.mp4 files with 1080p video and 48k audio) and hear it play back OK on the timeline! AND even though the project produced at 44.1 kHz, it sounds great. Unfortunately, the audio-video sync drifts when I produce a few of these test .mp4 files -- leading me to think full 48k support is not here yet.
Bottom line question, can someone from TS fill us in on what enhancements were made with respect to 48 kHz audio in v9?
Kevin Mojek, Employee
drbooshkit
Kevin Mojek, Employee
Ideally, I think we'd like our timeline to run at arbitrary frame rates up to 60-fps and have some choice available for the audio format. 48 kHz would seem like a reasonable default these days; I think 44.1 was chosen for CS 6 because that was "CD quality". That is something that is under discussion currently, so I can't comment at this point on when that might show up in a release.
For the specific example that you posted, what I'm seeing on two different machines (Win 7 and Win 8.1) is that the audio and video are out-of-sync almost from the very beginning during preview and production. I've opened an internal bug report on it but so far haven't had a chance to dig into it too far. I think what is happening, though, is a problem with the video stream. It is at a frame rate that is a little odd (29.95 fps) but normally that should not be a problem. Based on the testing I've done so far, it looks like what's happening is we're jumping around a bit trying to find the correct video frame to match the time of the audio. That's very inefficient compared to the normal behavior of mostly stepping through the video frame-by-frame; I think that is the source of the out-of-sync issue in this case. I tried re-encoding the video stream to a constant 30-fps while keeping the audio at 48 kHz and working with that file previewed and produced without sync issues. The webcam you are using is a very common one, so I checked one out from our QA folks and tomorrow I'm planning on seeing if I can reproduce the problem recording with that. If the recording software provides some control over the output format, that may be a temporary workaround for Camtasia not handling these files correctly. Otherwise, having more files to test with should help in narrowing down the decoding problem. I'll report back here once I have some more info.
drbooshkit
The Logitech Webcam Software (v2.80 now) has limited settings for output. So workaround might be finding a different webcam capture tool with more granular settings -- sounds like frame rate might be the key here.
Let me know if I can provide any other assets for testing.
Native 48kHz support would be in top 2 request for our company. #1 is White Balance control : )
Kevin Mojek, Employee
rg
frank.heney
https://en.wikipedia.org/wiki/SMPTE_timecode
rg
frank.heney
rg