site_archiver@lists.apple.com Delivered-To: pro-apps-dev@lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=33uxlqoyM5lS/LZN0K6BitnuCCXmRYyJ1psxMHVVZ8k=; b=xkADRkFMVw9YU7bbbGxK9rwNp3Y1IYOXKGXgGV3x3yaGpJx4SPCUKfhQLO85l46TuA fFqfZSyEJHebSgrK0Hbo9D5nvYtz2UEXcXc4ub+aFTOTm1BrTVc2KL4+yUY/bhtOj2yE LlWbRwDj6PL/tsGPdqCSI8w8KIXM3w9zx8wzw= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=trsRqCcw5RCbtboZMqV2T8sziIjji1A+u24nCuXmTKCskYLkw84Cnng42i+VeGjdB4 Lemvp2DKpn7HMkPBx8fQTRjwGEnkWXqvhd90QxDCbnOS+9OXTcjZjh56tALXFbuFISmd 1zJokHpOQVHFiziT0Wl3HfyJLKcRPw32bphew= [Re-sent to the whole list.] Comments below. On Mon, Feb 16, 2009 at 9:52 AM, Ky Hopwood <khopwood@apple.com> wrote:
You have audio that is not in sync with video and are trying to adjust the speed the video to match the audio?
That's about right, but more often I want to adjust the speed of the audio rather than the video.
Is you audio fine at the start, and then drifts linearly , or is completely ok and then at some point goes off?
It has a linear drift that I know to a high degree of precision.
In addition, I gather from what you are saying that you are not really using xml is this workflow, but rather you are using that simply to display the values of the speed keyframes. Is that correct?
XML is in the workflow. I am writing a plugin that helps with synchronization. It retrieves the project XML, analyzes the clips to determine the drift and writes back XML with a time remap speed parameter to compensate. My concerns are that (1) FCP may not respect the full precision of the speed parameter in the XML, (2) even if it does, it may not persist when the project is saved, and (3) if the user looks at the speed in the UI, its value will be corrupted. I'm pretty sure about #2 and #3, but I'm doing an experiment to assess #1 right now and will let you know shortly. Bruce On Mon, Feb 16, 2009 at 9:52 AM, Ky Hopwood <khopwood@apple.com> wrote:
I am not certain I have your scenario correct, so a few questions to verify.
You have audio that is not in sync with video and are trying to adjust the speed the video to match the audio? Is you audio fine at the start, and then drifts linearly , or is completely ok and then at some point goes off?
In addition, I gather from what you are saying that you are not really using xml is this workflow, but rather you are using that simply to display the values of the speed keyframes. Is that correct?
ky
I want to overlay clips from recording devices that are free-running (not jam-synched). Even though most of the clocks are pretty accurate, these are clips of live events that last a long time and over the course of many minutes it is not unusual for them to drift apart from one another by an amount that needs to be corrected. Time remap seems like a good mechanism to adjust things back into sync. But the speed value only seems to be able to retain numbers up to a precision of two decimal places. For example, enter 100.12345 in the user interface and 100.133 is what gets stored in the XML, which is not even rounded properly. The residual error over the length of an hour can be hundreds of milliseconds, which is not acceptable for many synchronization purposes.
I can't figure out if this is an artifact of the user interface or some fundamental limitation. Is there a sneaky way to specify a remap speed with greater precision?
Bruce
_______________________________________________ Do not post admin requests to the list. They will be ignored. Pro-apps-dev mailing list (Pro-apps-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/pro-apps-dev/bruce.sharpe%40gmail.com
This email sent to bruce.sharpe@gmail.com
_______________________________________________ Do not post admin requests to the list. They will be ignored. Pro-apps-dev mailing list (Pro-apps-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/pro-apps-dev/site_archiver%40lists.ap... This email sent to site_archiver@lists.apple.com