Some technical questions regarding video

[jayfro]

John,


I've taken some videos of my students anywhere from 1/250 to 1/1000 of a second shutter speed with my camcorder. Once I did that I took an individual stroke for each player and took anywhere from 40-60 pictures every 3 one hundredths of a second and put them in order so I could have a slide show that I could print off of my computer. I took the pictures after I put the video taken on my computer by using a NERO software program. Then using quicktime pro I did the same thing with some of the pros you have on this site to get a side by side visual comparison for my students at each stage of the swing.


My question is when I transfer this information to my computer why do I get noticeable blur in the pictures that I print off from my camcorder? Yet I get crystal clear pictures printed off from the videos you have on this site?


It's funny because when I play the 1/1000 of a second videos directly from my camcorder to my television I get little to no blur while going in slow motion and freezing certain parts of the stroke, I just want to be able to print that quality of image off on paper or be able to transfer it to DVD. I've been able to do some cool stuff with pro strokes videos in slow motion by transfering them to DVD and such, but I'm hoping to do even more to visually help my students.


One quick request if possible, any chance we will get some left handed male and female players in the strokes section? I would love to be able to give my left handed students a great look at the best of the best. Thanks John.




JayFro

[lukman41985]

I'm sure John will be putting up Nadal soon. Other than Rafael, there is a dearth of left-handed players on tour. There's Rusedski, Puerta, and hmmm...that's all I can think of...AJ? In the stroke archive, there are a few lefties already: Goran (serve), McEnroe, Connors, LeConte, and Gomez. However, I doubt your juniors will have any interest in modeling senior players!

[vmiller]

My question is when I transfer this information to my computer why do I get noticeable blur in the pictures that I print off from my camcorder?

It could be the lack of progressive scan. I bought my camcorder specifically for tennis, so I did a little research. Progressive scan, which is actually not very common among typical camcorders, maintains each frame as a picture (obviously much better for frame by frame analysis). Most camcorders blur each image so that it looks more seamless when going to the next frame.

[jayfro]

It could be the lack of progressive scan. I bought my camcorder specifically for tennis, so I did a little research. Progressive scan, which is actually not very common among typical camcorders, maintains each frame as a picture (obviously much better for frame by frame analysis). Most camcorders blur each image so that it looks more seamless when going to the next frame.

Thanks for the response.

[johnyandell]

jayfro,

I don't know that software. It sounds puzzling that they aren't clear but I don't have a clue to be honest. Try this: open the student sequence in QT and then export it as an image sequence. You'll get a series of stills of every frame. Try printing that. or the ones you want. In the Stroke Archive we shoot at 1/1000 minimum. If you are seing a little blurr at 250 or 500 that's to be expected.

On the lefty thing, Feliciano Lopez would be good besides the obvious. It's not quite as easy as we may make it appear though. We are filming at multiple events but if the player isn't there or loses, or plays at the same time as other players...we'll you get the idea. In the long run we hope to have everyone. I wouldn't sweat the lefty thing though. Players can automatically translate that. Some softwares like Dartfish let you flip the image if you're really serious about having more "lefty" images.


John

[jayfro]

jayfro,

I don't know that software. It sounds puzzling that they aren't clear but I don't have a clue to be honest. Try this: open the student sequence in QT and then export it as an image sequence. You'll get a series of stills of every frame. Try printing that. or the ones you want. In the Stroke Archive we shoot at 1/1000 minimum. If you are seing a little blurr at 250 or 500 that's to be expected.

On the lefty thing, Feliciano Lopez would be good besides the obvious. It's not quite as easy as we may make it appear though. We are filming at multiple events but if the player isn't there or loses, or plays at the same time as other players...we'll you get the idea. In the long run we hope to have everyone. I wouldn't sweat the lefty thing though. Players can automatically translate that. Some softwares like Dartfish let you flip the image if you're really serious about having more "lefty" images.


John

To John and everyone who responded thanks for the information and help you provided. I've still not been able to transfer the video even at 1000fps without seeing two rackets on the forward swing and noticeable blur, but it's still a great tool to be able to compare my students side by side with pros in picture form. My only other question is does it have anything to do with the fact that I'm filming inside for this stuff? I get the same crazy blur when I transfer these videos over to DVD.


My last question is would you suggest Dartfish or silicon coach? I've looked at both websites but I'm not really sure if there is much if any difference between the two products. Thanks again and great job on the backhand article, I've already started using the information in my lessons today with some of my juniors. It's great stuff and the reason why this site is like no other.


JayFro

[johnyandell]

Jayfro,

OK I think I know what is happening. Are you trying to play an AVI (PC) file in Quick Time? You can thank Bill Gates for the problem. Try playing the file in Windows media player. The frame advance isn't good but it should be clear.

You can convert the file to a QT in a (expensive) program like Cleaner Pro. But I have another idea. Beofre you invest in Dartfish or Silicon Coach, check out Motion Pro. It's cheap and doesn't have the viewing problems. You can use it to capture as well as play.

http://www.pdsoftec.com/

I've fooled around with it a bit and they do have great tech support. Can't say I'm an expert so why don't you investigate and be our guinea pig?

John

[vmiller]

JayFro,

I'm no video expert, but I still think your problem is that your camera uses interlaced scanning instead of progressive scanning. I've seen what you're talking about using frame by frame on a camcorder. My camcorder has progressive scan and this doesn't happen.

Here's some text from the Canon website describing the progressive scan in their Optura line of cameras and how it differs from interlaced scanning:

"The Optura is the world's first camcorder to incorporate a progressive scan CCD image sensor that delivers a significant improvement in performance and image quality. Each and every light gathering pixel on the CCD is used to reproduce a full frame video image 60 times per second. In contrast, the conventional interlace-type CCD reproduces only half a full frame, known as a field, in the same amount of time. During playback, the interlace method used on other camcorders combines two field images together, but a time lapse between the fields can cause a disturbing image flicker on the television screen when playback is paused. The Optura's progressive scan CCD eliminates the time lapse between fields by recording a full frame image, making it possible to output, display or even print the most exciting frame of a moving image without any loss in resolution."

This website has another description of the difference and also shows some examples. See if the pictures are similar to what you're seeing. Particlularly the one of the car wheel where you can almost see two of them.

http://www.axis.com/products/video/camera/progressive_scan.htm

Hope that helps.

[jayfro]

JayFro,

I'm no video expert, but I still think your problem is that your camera uses interlaced scanning instead of progressive scanning. I've seen what you're talking about using frame by frame on a camcorder. My camcorder has progressive scan and this doesn't happen.

Here's some text from the Canon website describing the progressive scan in their Optura line of cameras and how it differs from interlaced scanning:

"The Optura is the world's first camcorder to incorporate a progressive scan CCD image sensor that delivers a significant improvement in performance and image quality. Each and every light gathering pixel on the CCD is used to reproduce a full frame video image 60 times per second. In contrast, the conventional interlace-type CCD reproduces only half a full frame, known as a field, in the same amount of time. During playback, the interlace method used on other camcorders combines two field images together, but a time lapse between the fields can cause a disturbing image flicker on the television screen when playback is paused. The Optura's progressive scan CCD eliminates the time lapse between fields by recording a full frame image, making it possible to output, display or even print the most exciting frame of a moving image without any loss in resolution."

This website has another description of the difference and also shows some examples. See if the pictures are similar to what you're seeing. Particlularly the one of the car wheel where you can almost see two of them.

http://www.axis.com/products/video/camera/progressive_scan.htm

Hope that helps.

Thanks for the reply, I'm using the Canon Optura 80 and I'll check to see if I have any options on this issue. Right now I can show my students images that have little to no blur directly on the LCD of the camcorder during the lesson or I can connect to a TV with the cables provided for a direct non blur picture. I'm still hoping to transfer the images to DVD for them without blur. Thanks again.


JayFro

[vmiller]

OK, I didn't realize you were getting clear frames directly from the camera. Looking back, I see that I missed that from your first post. Sorry about that.

I'll double check when I get home, but I think my camera is the Optura 30 and I'm using an older version of Ulead VideoStudio to transfer the video to PC. I'm able to create a .avi file that I can step through in quicktime with each frame being a clear picture. I don't know much about this kind of software, and I don't really like what I'm using, but it at least gets the job done.

Maybe you're doing something wrong with the Nero software? There's a forum on www.camcorderinfo.com that you might be able to get better help from. You may also want to do some searching on golfers using camcorders to record their swings. When I was researching cameras, I found more helpful information relating to golf.

Good luck and let me know if you find better software.

[jayfro]

OK, I didn't realize you were getting clear frames directly from the camera. Looking back, I see that I missed that from your first post. Sorry about that.

I'll double check when I get home, but I think my camera is the Optura 30 and I'm using an older version of Ulead VideoStudio to transfer the video to PC. I'm able to create a .avi file that I can step through in quicktime with each frame being a clear picture. I don't know much about this kind of software, and I don't really like what I'm using, but it at least gets the job done.

Maybe you're doing something wrong with the Nero software? There's a forum on www.camcorderinfo.com that you might be able to get better help from. You may also want to do some searching on golfers using camcorders to record their swings. When I was researching cameras, I found more helpful information relating to golf.

Good luck and let me know if you find better software.

Well thanks for the help once again, I was able to transfer and save video by creating an AVI file and from that I played the videos in the quicktime player. In the quicktime player itself going frame by frame I don't get any blur, but when I printed off the pictures from quicktime I got double rackets and the same blur from racket head speed. I guess I'll just keep searching for an answer because I would love to be able to print off non blurred picture sequences and also put these on DVD without blur. My only other answer was that maybe filming indoors was part of the problem. The video I've been trying to print off was filmed at 1/1000 indoors. Thanks again.


Edit: I played around with it some more and I was able to use those AVI files and transfer them to DVD and they can be paused with little to no blur. I was also able to get those pictures from the AVI files to print out but they are very dark. Thanks again for all the help, I appreciate it and so will my students.


JayFro

[jerryo]

Cam Corder

What is the make and model of the camcorder that you are using. We are planning to purchase one for our clinics and this information will be helpful

Thanks.

jerryo

[vmiller]

I'm not sure who you're asking, but mine is the Canon Optura 20. I got it almost two years ago and I don't think it's available any more, but the Optura line is still available.

It has met all my needs for tennis. The frame by frame is clear and the display screen is big enough to watch the video on court. The only complaint I have is that the frame by frame controls are only on the remote.

[jayfro]

What is the make and model of the camcorder that you are using. We are planning to purchase one for our clinics and this information will be helpful

Thanks.

jerryo

The camcorder I have is the Canon Elura 80. Which can be found at the link below, I purchased it about 4 months ago.

http://www.circuitcity.com/ssm/Canon-Camcorder-Elura-80-/sem/rpsm/oid/116767/rpem/ccd/productDetail.do

[MotionPro]

double images in video clips

Hi, this is David Hill, the president of PDSOFTEC and the primary author of the MotionPro video analysis software. I caught sight of this thread in a google search I ran and thought I would drop in to help.

I can tell you the double-images (two tennis racquets, or two arms...) are artifacts of video interlacing, and the program you are viewing or printing with simply does not know how to "deinterlace" it. This is a very common experience when using firewire video.

I invite you to take John Yandel up on his suggestion (earlier in this thread) to try MotionPro! This software will allow you to view video clips (deinterlaced by default!), break them out into individual frames automatically, to copy/print the images directly, etc etc. You can also do side by side comparison, and much much more. To view Quicktime movies you will need a free Quicktime codec called "alternate quicktime" to view the videos in MotionPro! If you don't have it, just drop me a note and I'll point you to it.

I'm not here to spam you folks, but please feel free to email me directly or to post here on this forum if you have specific questions I can help you with.

Thanks,

David Hill
President

https://www.pdsoftec.com