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Comparing trigger speed of cameras SX230 and SD1100 / IXUS 80

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Re: Comparing trigger speed of cameras SX230 and SD1100 / IXUS 80
« Reply #10 on: 25 / February / 2012, 21:25:13 »
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Turned Pixel Step up to 50 - debatable whether it improved performance. Most shots were still around 130 but a few got 90, so I think that has to do with variation in each shot more than anything about the pixel step.

Turns out default parameters have it as Y, so that's what I was already using. What do the other ones mean? It says 0U, 1Y, 2V, 3R, 4G, 5B. Default is 1.
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I use the chdk on my SX230 and SD1100 cameras, and I installed them using a Macbook, currently running 10.6.8.

Re: Comparing trigger speed of cameras SX230 and SD1100 / IXUS 80
« Reply #11 on: 25 / February / 2012, 21:30:34 »
What do the other ones mean? It says 0U, 1Y, 2V, 3R, 4G, 5B. Default is 1.
from the motion_detect.h file :
Code: [Select]
purpose of the module:
 implement 2 uBASIC procedures
   md_detect_changes( columns [in], rows [in], pixel_measure_mode,  )
   md_get_cell_change ( col [in], row [in], val [out] )

explanation:

 - for motion detection used array of YUV pixels which are used to display thumbnail picture on LCD

declaration:

function md_detect_changes (

  columns, // input parameter. number of columns to split screen into

  rows, // input parameter. number of rows to split screen into

  pixel_measure_mode, // input parameter.
// 1 - for Y,
    // 2 for U, - (mx3)not sure if this mode required
    // 3 for V, - (mx3)not sure if this mode required
    // 4 for gray, - (mx3)not sure if this mode required
    // 5 for R, - (mx3)not sure if this mode required
    // 6 for G, - (mx3)not sure if this mode required
    // 7 for B - (mx3)not sure if this mode required
// 9 for face detection

  detection_timeout, // input parameter. number of millisecnds to abort detection. detected_cells_count will be 0 for timeout condition

  measure_interval, // input parameter. number of milliseconds between comparison of two pictures

  threshold, // input parameter. difference value for which procedure will trigger detection of changes

  draw_grid, // boolean input parameter.
             // true(1) to draw grid(detected sectors/cells).
             // false(0) - to not display grid/detected sectors

  detected_cells_count, // output parameter. count of cells where pixel values differs enough to trigger motion detection

// clipping. allows to exclude some region from mtion detection triggering
// or use onli selected area to make motion detection
// I'm not sure that following parameters are required but using them anyway

  clipping_region_mode, // input parameter.
// 0 no clipping regions
      // 1 - for excluding selected region from motion detection
      // 2 - use this only region to make motion detection
  clipping_region_column1, // input parameter.
  clipping_region_row1, // input parameter.
   // this is top-left corner of clipping region

  clipping_region_column2, // input parameter.
  clipping_region_row2, // input parameter.
// this is right bottom corner of clipping region
)

Ported :   A1200    SD940   G10    Powershot N    G16

Re: Comparing trigger speed of cameras SX230 and SD1100 / IXUS 80
« Reply #12 on: 25 / February / 2012, 21:36:27 »
Unless I'm missing something, that script still just says the letters Y, U, V, R, etc. I was asking what those letters mean. I tried googling it but its difficult to get useful results for single letters. The wiki page for the motion detect script doesn't seem to explain it either. Sorry if I missed something obvious.
My Flickr Page
I use the chdk on my SX230 and SD1100 cameras, and I installed them using a Macbook, currently running 10.6.8.

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Re: Comparing trigger speed of cameras SX230 and SD1100 / IXUS 80
« Reply #13 on: 25 / February / 2012, 21:49:01 »
Unless I'm missing something, that script still just says the letters Y, U, V, R, etc. I was asking what those letters mean. I tried googling it but its difficult to get useful results for single letters. The wiki page for the motion detect script doesn't seem to explain it either. Sorry if I missed something obvious.
http://en.wikipedia.org/wiki/YUV
http://en.wikipedia.org/wiki/RGB_color_model
 :)


Re: Comparing trigger speed of cameras SX230 and SD1100 / IXUS 80
« Reply #14 on: 25 / February / 2012, 21:53:02 »
Unless I'm missing something, that script still just says the letters Y, U, V, R, etc. I was asking what those letters mean. I tried googling it but its difficult to get useful results for single letters. The wiki page for the motion detect script doesn't seem to explain it either. Sorry if I missed something obvious.
Sorry - the trick to googling them is to realize they are the letters for the YUV or RGB color spaces.

http://en.wikipedia.org/wiki/YUV

http://en.wikipedia.org/wiki/RGB

Basically - AFAIK it lets you pick which colors the motion detection is sensitive to.

Update : Best place to look for details is in the source ... core/motion_detect.c.


« Last Edit: 25 / February / 2012, 21:54:54 by waterwingz »
Ported :   A1200    SD940   G10    Powershot N    G16

 

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