hyeom@cs.tamu.edu (Heon Y Yeom) (09/07/90)
Hi, Forgive me if my question is something trivial. I have the following problem. We have a video tape recorded on a highway from the side of the road. I need to somehow identify the vehicles passing by without somebody watch the tape for couple hours. I have a relatively simple frame grabber which is able to capture video data 60 times per second with 64 grayscale. What I'd like to do is to move the video to a series of image files and process them. Is there an algorithm to detect moving obect from a series of images ? Graphics and Image processing is new to me and I don't know where to look for. Any help would be greatly appreciated. Thanks! ============================================================================== | Heon Y. Yeom | | (Internet) : hyeom@cssun.tamu.edu | | (Bitnet) : hyy5325@tamvenus | | (Tel) : (409) 845-6211 | | (U.S.mail) : CE/TTI 402, TEXAS A&M Univ. College Station, Tx. 77845 | ==============================================================================
black@beno.CSS.GOV (Mike Black) (09/07/90)
In article <8010@helios.TAMU.EDU> hyeom@cs.tamu.edu (Heon Y Yeom) writes: >Forgive me if my question is something trivial. >We have a video tape recorded on a highway from the side of the road. >I need to somehow identify the vehicles passing by without somebody watch the >tape for couple hours. >I have a relatively simple frame grabber which is able to capture video data >60 times per second with 64 grayscale. What I'd like to do is to move the >video to a series of image files and process them. >Is there an algorithm to detect moving obect from a series of images ? What you want to do Heon is basically a form of frame-to-frame comparison. What you do could depend on what your image hardware is capabile of but would involve this: 1. Since you are working with a static scene a car entering the field of view will cause a variation in intensity in the image. A dark car would decrease the intensity and a light car would increase it. You can subtract all the pixels in one frame from the last frame and examine them for a certain amount of change. i.e. 100 pixels varying more than 10 might work. 2. This involves a lot of number crunching for an image. You may be able to undersample the image to reduce the processing. For example, if a car occupies 1/3 the field-of-view on a 512x512 pixel image, you could examine every 10th line and every 10th pixel and reduce your processing by two orders of magnitude. It simply depends on how large the car is in the image. 3. Your image hardware may already have some of these functions. If you wish to converse further, please e-mail and I'll help you out. Mike... -- ------------------------------------------------------------------------------- : usenet: black@beno.CSS.GOV : land line: 407-494-5853 : I want a computer: : real home: Melbourne, FL : home line: 407-242-8619 : that does it all!: -------------------------------------------------------------------------------
landheim@bbn.com (Greg Landheim) (09/07/90)
In article <8010@helios.TAMU.EDU> hyeom@cs.tamu.edu (Heon Y Yeom) writes: >We have a video tape recorded on a highway from the side of the road. >I need to somehow identify the vehicles passing by without somebody watch the >tape for couple hours. It _sounds_ like you're trying to spy anonymously on people. If that's what you are up to, say so, and you will have my utmost contempt. If you're doing something legitimate, I would like to know what it is.
murray@vs2.scri.fsu.edu (John Murray) (09/10/90)
In article <59350@bbn.BBN.COM> landheim@spcwsa.bbn.com (Greg Landheim) writes: >In article <8010@helios.TAMU.EDU> hyeom@cs.tamu.edu (Heon Y Yeom) writes: >>We have a video tape recorded on a highway from the side of the road. >>I need to somehow identify the vehicles passing by without somebody watch the >>tape for couple hours. > >It _sounds_ like you're trying to spy anonymously on people. If that's >what you are up to, say so, and you will have my utmost contempt. If >you're doing something legitimate, I would like to know what it is. Yeesh, lighten up! You think it's impossible that Heon could be involved in something legitimate (or at least legal?) Example: I understand that at one point the State of Texas was beta- testing an "automatic speeding ticket" system. The setup was basically a doppler radar like the police use, with a (video?) camera, set up in a secure box on the side of a highway. You drive by at excessive speed, the radar detects you, the camera gets a picture of the rear end of your car - your license plate in particular.. and you get a ticket in the mail a week later. Say, I wonder if you could get accurate enough velocity information from successive frames of a video tape, to do this without the radar? Whoops! Better get my patent applications out! Incidentally, the Texas system was shelved. It seems the equipment suddenly started experiencing catastrophic failures. Something to do with large holes or tight clusters of smaller holes in the outer boxes... I love Texas :-} John R. Murray | "They call me Mr. Know-it-all, I am so eloquent. murray@vs2.scri.fsu.edu | Perfection is my middle name! | ...and whatever rhymes with 'eloquent'." - Primus
bdb@becker.UUCP (Bruce D. Becker) (09/11/90)
In article <59350@bbn.BBN.COM> landheim@spcwsa.bbn.com (Greg Landheim) writes: |In article <8010@helios.TAMU.EDU> hyeom@cs.tamu.edu (Heon Y Yeom) writes: |>We have a video tape recorded on a highway from the side of the road. |>I need to somehow identify the vehicles passing by without somebody watch the |>tape for couple hours. | |It _sounds_ like you're trying to spy anonymously on people. If that's |what you are up to, say so, and you will have my utmost contempt. If |you're doing something legitimate, I would like to know what it is. It _sounds_ like *you* have an insufferably suspicious disposition. It is common courtesy to give the benefit of the doubt in this situation - "innocent until proven guilty" probably applies here, at least informally. He's under no obligation to say why he needs this - one can imagine quite a number of legitimate scenarios. You're out of line to prod him this way, especially in a public forum, unless you have clear grounds for your insinuations. Your demand for disclosure is in itself an insult, even when taken separately from your other statements. -- ,u, Bruce Becker Toronto, Ontario a /i/ Internet: bdb@becker.UUCP, bruce@gpu.utcs.toronto.edu `\o\-e UUCP: ...!uunet!mnetor!becker!bdb _< /_ "I still have my phil-os-o-phy" - Meredith Monk