Hello Giles, I did the time measurments for both microcontroler acquisition and bluetooth comunication to the PC.
For the BT transmission duration, I've noticed that the more lines I extracted, the more bytes I had to transmit, so the transmision time increased as expected. For the microcontroler acquisition duration, I was expecting also an increase with the number of lines taken, since more lines needed to be acquired. Instead I get more or less a constant value arround 400ms, for evry camera configuration, with a huje jitter value (standard deviation of the captures is arround 100-150ms). I went to po3030k.h where it is written the frame rates for some camera configurations. Mine is not there ( GRAY (1-8)x480 with zoom of 1,2,4,8 ) but I was expecting it be arround the maximum frame rate (8 fps). Instead I'm getting arround 2 fps with huje jitter. I want to take out the Jitter of the captures and obtain the maximum frame rate that the configurations I am using allow. What should be the durations that I should obtain for microcontroler acquisition with my camera configurations? Regards, Duarte 2011/7/21 Gilles Caprari <g.capr...@ieee.org> > ** > Dear Duarte, > > this example might be an inspiration > http://www.gctronic.com/doc/index.php/E-Puck#Still_images > > usign the zoom basically skips pixels and lines and takes only the one > usefull. Not sure if you mean acquisition from the microcontroller or also > on the PC via bluetooth (BT). In that later case, most of the time required > by the BT communication. > > regards, > Gilles > > > On 20:59, Duarte Dias wrote: > > Hi, > > I am using the e-puck 1176 (VGA camera 480x640 - rotated camera). > > I am capturing some full (480 pixels) horizontal lines (1 to 8 lines) > applying the zoom factor of 1, 2, 4 and 8 (on the x component which in this > epuck camera is the vertical component). > > I assume that if I am capturing 4 horizontal lines with zoom 2 its the > same of capturing 8 lines with zoom 1 (and so one). The zoom just does the > line averaging within groups of 2 lines. > > When I capture the images I am using a timer (TIMER1) to quantify the > capture duration. > > After my experiments from capturing 1 - 8 lines with zoom 1,2,4,8 I have > concluded that the capture time is approximatly constant (between 350 and > 450), no matter the number of lines we take and the zoom we do. > > I have also witnessed a large Jitter between frame captures (the standard > deviation of the frame capture times is arround 150ms!). > > I was expecting a rise of time when I extracted more lines and no Jitter > should exist. Could someone tell me what I could be the cause of this > behaviour (expecially the Jitter behaviour). > > Regards, > Duarte Dias > > > -- > ------------------------ > Dr. Gilles Caprari > GCtronic Sagl, Electronics & Mechatronics > web: www.gctronic.com E-mail: g.capr...@ieee.org > Post: Via Cassarinetta 2, CH-6900 Lugano, Switzerland > Tel: +41 91 630 2149 Fax: +41 43 556 8006 > Mobile: +41 78 601 1113 skype: gillescaprari > >
_______________________________________________ E-puck-user mailing list Eemail@example.com https://mail.gna.org/listinfo/e-puck-user