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I fetch data from 420 TVL camera, and now I just want to see this image, the only thing I need is resolution to draw it on my screen. How can I determine this?

BWP M420MD -- camera, I'm getting DCMI data from decoder TVP5150AM1

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  • \$\begingroup\$ Which camera? Do you have a datasheet for the camera? \$\endgroup\$ – JRE Oct 23 '18 at 13:38
  • \$\begingroup\$ Add in the question \$\endgroup\$ – stronk_kisik Oct 23 '18 at 14:00
  • \$\begingroup\$ Enlish datasheet? \$\endgroup\$ – Alexander von Wernherr Oct 23 '18 at 14:07
  • \$\begingroup\$ @AlexandervonWernherr, couldn't find but I don't think it is matter, decoder datasheet states that resolution 720x525 but I couldn't prove this, because I didn't understand how to correctly read how many pixels I get between to HSCLK. \$\endgroup\$ – stronk_kisik Oct 23 '18 at 14:11
  • \$\begingroup\$ The answers should be in the decoder datasheet. The camera is analog. \$\endgroup\$ – JRE Oct 23 '18 at 15:21
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TVP5150 will give 720 active pixels regardless of input signal. But the horizontal total will be either 864 or 858 pixels depending on signal being PAL or NTSC so that depends on your camera. You get two clocks per pixel as the data output is multiplexed between Y data and C data. C data is also multiplexed between Cb and Cr.

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  • \$\begingroup\$ I'm sorry but in documentation "active pixels per line" -> 720 , "lines per frame" -> 525. Doesn't this mean that resolution is 720x525? \$\endgroup\$ – stronk_kisik Oct 24 '18 at 10:08
  • \$\begingroup\$ No, 525 is the total interlaced lines per full NTSC frame. \$\endgroup\$ – Justme Oct 24 '18 at 18:23
  • \$\begingroup\$ Could you please elaborate this for me? I really doesn't understand why the number of lines are nor equal to the vertical resoultion if lines are interlaced it's just means that there are odd and even fields so number of lines divided by two. And maybe you can help me with my next problem, how should I configure DCMI->ESCR DCMI->ESUR registers for embedded synchronization with SAV EAV codes on STM32H7? I understand that there are should be 4 SAV EAV codes (line start, line end, line start with VB, line end with VB) for each of the fiels, so 8 in total. but there I only can configure 4 of them \$\endgroup\$ – stronk_kisik Oct 25 '18 at 9:53
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    \$\begingroup\$ If it's a NTSC camera, it will output 525 lines, of which 480 or so contain active picture area as and the rest are used for synchronization. \$\endgroup\$ – Justme Oct 25 '18 at 16:54

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