Motion issue with Flash encoding at DVinfo.net

Joshua Clarke · January 25th, 2009, 03:00 PM

I have been encoding a few videos from an HDV source into Flash (.flv) using Premiere Pro 2.0's Adobe Media Encoder. The quality is fine, but when I play back using Adobe's Flash Player, I notice there are problems with motion. The best way I can describe it is, in scenes of moderate to heavy motion, a horizontal line will appear where it's almost as if what is above the line is out of sync with what is below the line. The line will only appear for a frame or so, and then disappear. However, this goes on for however long there is a degree of motion, appearing in various parts of the frame. I've tried to take a screenshot of the problem, but either cannot get it or the problem occurs only during playback.

Any suggestions on how to fix this?

Graham Hickling · January 25th, 2009, 10:37 PM

Do you still get the same effect if you play it back on another computer?

Andy Wilkinson · January 25th, 2009, 11:41 PM

From you're description this is a pretty common issue with all Flash and can be seen all over the web.

Horizontal panning (especially of a complex scene) will typically give this "break" where one half or one third (or whatever) of the picture seems to lag behind the remainder for a fraction of a second. This effect is (unfortunately) totally normal for Flash and is the price we pay for accessible web video encoded with relatively small amounts of data.

Joshua, I went through a similar "is it something I've done wrong" problem solving procedure when I first started doing web video (especially after Stage6 folded as they used the DivX rather than Flash encoding and that does not seem to exhibit this fault).

But Flash is universal and DivX is not and that's just the way it is. If you want the world to view your videos then Flash is the way to go, faults and all.

Also, for videos I "shoot for web" I tend to adjust my shooting style to avoid too much (or too fast) horizontal panning as this triggers the fault described. It's all about knowing the limitations and working as best you can within them to get a great product!

Joshua Clarke · January 26th, 2009, 03:16 PM

Andy, great information. Thank you very much.

Unfortunately, when we shot this we knew what the final delivery was, but we didn't know in what format. I was figuring .wmv, with which I've never had a problem. The web designer that was hired is the one who pushed for Flash, so that's what we had to go with. Thanks again for the info and I'll keep what you said in mind.

Graham, yes, unfortunately it shows up on two systems.

January 25th, 2009, 03:00 PM	#1
Joshua Clarke Regular Crew Join Date: Jul 2006 Location: Philadelphia, PA Posts: 88	Motion issue with Flash encoding I have been encoding a few videos from an HDV source into Flash (.flv) using Premiere Pro 2.0's Adobe Media Encoder. The quality is fine, but when I play back using Adobe's Flash Player, I notice there are problems with motion. The best way I can describe it is, in scenes of moderate to heavy motion, a horizontal line will appear where it's almost as if what is above the line is out of sync with what is below the line. The line will only appear for a frame or so, and then disappear. However, this goes on for however long there is a degree of motion, appearing in various parts of the frame. I've tried to take a screenshot of the problem, but either cannot get it or the problem occurs only during playback. Any suggestions on how to fix this? __________________ Section 1 Films

January 25th, 2009, 11:41 PM	#3
Andy Wilkinson Inner Circle Join Date: Sep 2007 Location: Cambridge UK Posts: 2,853	Motion Horizontal Breaking with Flash Video From you're description this is a pretty common issue with all Flash and can be seen all over the web. Horizontal panning (especially of a complex scene) will typically give this "break" where one half or one third (or whatever) of the picture seems to lag behind the remainder for a fraction of a second. This effect is (unfortunately) totally normal for Flash and is the price we pay for accessible web video encoded with relatively small amounts of data. Joshua, I went through a similar "is it something I've done wrong" problem solving procedure when I first started doing web video (especially after Stage6 folded as they used the DivX rather than Flash encoding and that does not seem to exhibit this fault). But Flash is universal and DivX is not and that's just the way it is. If you want the world to view your videos then Flash is the way to go, faults and all. Also, for videos I "shoot for web" I tend to adjust my shooting style to avoid too much (or too fast) horizontal panning as this triggers the fault described. It's all about knowing the limitations and working as best you can within them to get a great product! __________________ Andy K Wilkinson - https://www.shootingimage.co.uk Cambridge (UK) Corporate Video Production

January 26th, 2009, 03:16 PM	#4
Joshua Clarke Regular Crew Join Date: Jul 2006 Location: Philadelphia, PA Posts: 88	Andy, great information. Thank you very much. Unfortunately, when we shot this we knew what the final delivery was, but we didn't know in what format. I was figuring .wmv, with which I've never had a problem. The web designer that was hired is the one who pushed for Flash, so that's what we had to go with. Thanks again for the info and I'll keep what you said in mind. Graham, yes, unfortunately it shows up on two systems. __________________ Section 1 Films

January 25th, 2009, 10:37 PM	#2
Graham Hickling Trustee Join Date: May 2004 Location: Knoxville, Tennessee Posts: 1,669	Do you still get the same effect if you play it back on another computer?