[Mjpeg-users] y4mstabilizer bugs
I recently took some really unsteady video (walking on sand, partially zoomed in; we're talking the bridge of the Enterprise after a direct hit shaky) and decided to test the limits of y4mstabilizer. It seems to be up to the task in theory (if one doesn't mind much of a given frame being off-screen), but I have run into some bugs related to the large offsets. I'm working on 640x480 progressive video in this case, and the required motion compensation can easily exceed 200 pixels in any direction. If I use a small radius with y4mstabilizer (say the 15 pixel default) then it tends to segfault as soon as the motion is greater than that, which is to say right away. I can keep things going longer by increasing the radius a lot, but sometimes in the 200-235 pixel range I get immediate segfaults anyway. Then if I use a radius of 236 or more, y4mstabilizer no longer operates correctly, but after the first few frames just shows a fixed corner of the video. The first type of segfault (from too large a motion) is the most important, and I've narrowed it down to the motion estimation code, specifically gmotion() or motion(). I'll track it down myself eventually, but I thought I'd throw it out there in case someone more familiar with the code wanted to take a crack at it. I can provide example video sequences. Dan - Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Mjpeg-users mailing list Mjpeg-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mjpeg-users
Re: [Mjpeg-users] y4mstabilizer bugs
Dan Scholnik wrote: > I recently took some really unsteady video (walking on sand, partially > zoomed in; we're talking the bridge of the Enterprise after a direct > hit shaky) and decided to test the limits of y4mstabilizer. It seems > to be up to the task in theory (if one doesn't mind much of a given > frame being off-screen), but I have run into some bugs related to the > large offsets. I'm working on 640x480 progressive video in this case, > and the required motion compensation can easily exceed 200 pixels in > any direction. If I use a small radius with y4mstabilizer (say the 15 > pixel default) then it tends to segfault as soon as the motion is > greater than that, which is to say right away. I can keep things going > longer by increasing the radius a lot, but sometimes in the 200-235 > pixel range I get immediate segfaults anyway. Then if I use a radius of > 236 or more, y4mstabilizer no longer operates correctly, but after the > first few frames just shows a fixed corner of the video. A pixel adjustment of greater than 200? Wow!! I never anticipated anything THAT shaky! Are you following the recommended filter sequence? (progressive, 444 input?) > > The first type of segfault (from too large a motion) is the most > important, and I've narrowed it down to the motion estimation code, > specifically gmotion() or motion(). I'll track it down myself > eventually, but I thought I'd throw it out there in case someone more > familiar with the code wanted to take a crack at it. I can provide > example video sequences. It sure seems to be a bug. It should be easy to isolate, since it should only need a couple of input frames. If you make them available, then I will see what I can do. Please provide some y4m sequences that illustrate the two problems, along with your calling parameters. The shorter the sequences that illustrate the problems, the better. I must tell you that in two weeks, I will be taking a one-month business trip. I will try to work on it while I am out, but time will be limited. Thanks. Jim Macropol - Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Mjpeg-users mailing list Mjpeg-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mjpeg-users
Re: [Mjpeg-users] y4mstabilizer bugs
On Tue, 11 Jul 2006, Dan Scholnik wrote: > I recently took some really unsteady video (walking on sand, partially > zoomed in; we're talking the bridge of the Enterprise after a direct... ... > pixel default) then it tends to segfault as soon as the motion is > greater than that, which is to say right away. I can keep things going > The first type of segfault (from too large a motion) is the most > important, and I've narrowed it down to the motion estimation code, > specifically gmotion() or motion(). I'll track it down myself ... Interesting! I also am seeing a segfault in y4mstabilizer. Had a VHS tape that was a little unstable (shakey in the vertical direction - tape jitter, etc) - no where near 200 pixels though. After 41 frames of still (black screen leadin) y4mstabilizer segfaults on the first non-black frame. Even more strangely this only seems to happen on PPC based systems, on a AMD64 system no segfault. I've saved a 500 frame sample which triggers the behaviour - maybe when I get back from vacation I'll have time to poke around in the code (the area of segfault is in the gmotion() routine it seems). Cheers, Steven Schultz - Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Mjpeg-users mailing list Mjpeg-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mjpeg-users
[Mjpeg-users] [OT] CMX 3600
Hi all Is there any chance someone has a tool (or knows a tool) that would translate a SMIL script into a edl CMX3600 file ? Thanks a lot E - Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 ___ Mjpeg-users mailing list Mjpeg-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mjpeg-users
