Re: getInputBitmap:withInfo:atTime: produces darker images in FCP
Re: getInputBitmap:withInfo:atTime: produces darker images in FCP
- Subject: Re: getInputBitmap:withInfo:atTime: produces darker images in FCP
- From: Stonewall Ballard <email@hidden>
- Date: Mon, 3 Nov 2008 17:40:30 -0500
Paul,
This is very odd. It turned out that the darkening happens only with
certain clips, in particular, the one I was using to test my plugin.
This darkens in both your test plugin and mine.
I cut a 1 sec. section out of it and put it here:
<http://stonetics.com/GammaExhibit.mov>. About 3.9MB.
I don't know why this one is different. I made it in AE by adding
noise to an ArtBeats freebie movie. The original clip from ArtBeats
does not show this effect. It's compressed using Photo JPEG, though.
This clip is DV/DVCPRO NTSC. Other clips with the same compressor that
I tried do not show the darkening.
I also found that using R408 pixels bypassed the problem.
Can you tell why this clip is darkened when fetched by the Temporal
API? I suppose it could be something mangled in this clip, but I don't
see what it is.
Thanks.
- Stoney
On Nov 3, 2008, at 4:37 PM, Paul Schneider wrote:
Hi Stoney,
This isn't a known problem, and I can't reproduce it with a simple
test plugin. Here's the plugin I'm using to test:
<TemporalAPI.zip>
I believe that one difference between FCP and Motion is that if you
request a non-existent frame (a frame that is before the start of
the media or after the end), Motion will clamp to the nearest
available frame while FCP will return an all-zero bitmap. Are you
averaging multiple frames together? That could produce darker
frames if some of the images aren't there.
- Paul
On Oct 31, 2008, at 7:46 PM, Stonewall Ballard wrote:
IN FCP 6.0.4, [temporalApi getInputBitmap: &bitmap withInfo:
renderInfo atTime: renderInfo.frame] in a renderOutput: call,
produces a significantly darker image than the FxBitmap in
inputImage. This is with software rendering, and any quality
setting. Motion produces the same image in both cases.
I'm using RGB pixels.
I see in the SDK Overview, that Motion 3.0.2 has fixed a bug "Image
Well Gamma Shift", which sounds related.
Is this a known bug? Is there a workaround? Does this happen with
YUV pixels too?
TIA for any advice.
- Stoney
--
Stonewall Ballard
email@hidden http://stoney.sb.org/
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Pro-apps-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden
--
Stonewall Ballard
email@hidden http://stoney.sb.org/
_______________________________________________
Do not post admin requests to the list. They will be ignored.
Pro-apps-dev mailing list (email@hidden)
Help/Unsubscribe/Update your Subscription:
This email sent to email@hidden