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EVAL-ADV7619-7511 Video Evaluation Board to grab a single frame

I am an electronic hobbiest  who works in a telecommunication holding company. I am a beginner in the microprocessors world and want to realize a single frame image grabing project with the help of your EVAL-ADV7619-7511 video evaluation board.

At the moment i am using a Pi 3 and i have a Spartan-3E Starter Board ( I do not have any experience with fpga's yet )

I will have 2 questions about EVAL-ADV7619-7511 video evaluation board and some underlying concept about HDMI receiving:

1.) As it is shown in the Block Diagram of the product it consist of 2 HDMI inputs. What procedure i should follow to grab a single frame from the J2 video jumper pins preferably with the help of Raspberry Pi 3 or Spartan3E gpio pins? 

2.) Let's assume that the HDMI input content is in 4K format. Is this means that the video output pixel clock will automatically synchronized with the input content pixel clock or is it possible to set any video output pixel clock to grab a desired resolution lets say 640x480@60 Hz Industry standard (pixel clock 25.175 MHz) for example.  
Briefly: Is 4K x 2K in --->  640x480@60 Hz (pixel clock 25.175 MHz) out possible?

Thank you!


  • Hi,

     Do you have one of our evaluation board?

     Video output pixel clock will automatically synchronized with the input content pixel clock ?

          Yes,The LLC(Line-Locked output for the pixel data)clock will be the pixel rate
       The LLC is a line locked clock. i.e. it is a clock that is locked to the length of the incoming horizontal line of incoming video.
       The LLC is designed to speed up or slow down in order to compensate for horizontal lines of video that are too long/short.   This prevents video data being lost.
    The LLC is nominally  27 MHz and can vary by +/- 5% to compensate for horizontal lines of video that are too long/short.
    The LLC cannot be programmed to output a fixed 27MHz clock.

    Thanks,

    Poornima

  • 1) The Spartan would need to be connected to the ADV7612 output pin via the jumpers and implement a simple frame buffer to capture one frame.  The the frame could be down loaded in the Raspberry Pi.  The item to look out for is the frame buffer size.  For 480p format the frame buffer size would be 640x480x24 = 7,372,800 bit, more than the Spartan 3 has if I recall correctly.  Of course the ADV7612 output could be set to 4:2:2 format cutting the frame buffer by a third.

    I am not familiar with the Pi 3 features and whether it could read the video stream directly.

    2) The ADV7612 cannot convert formats.  What goes in is what comes out.

    If you are new to video processing I would recommend the book "Video Demystified".  It's a good go to book for anything video related.  Beyond this I would begin reading VESA, CTA and HDMI specifications.  (Or ask questions on this forum)

  • Thank you for your replies. 

    I would greatly appreciated if you can explain the sequential technical detail to successfully buffer one 480p format single frame from which jumpers?

    An explanation example that i am after is something like this: To successfully complete a one full cycle of a 480p format frame; you need to monitor the HS pin until it will go (high/low). When HS pin become desired logical state this means that the horizantal line is started. Every horizantal line is composed of 640 pixels wide. The pixel bits are appeared from jumper pins through D_RX0 ... D_RX36 (in this order) with a clock speed of  LLC(Line-Locked output for the pixel data clock) . You need to sample until the VS pin's logical state become the desired state which means that the next horizantal line is started and this procedure continues until some jumper pin logical state become the desired state which will mean that you have reached the end of a one frame period.

    I hope i could explain what kind of an answer i am after.

    I really read many documents about the topic and  the Video Demystified's HDMI section today but i can not apply any of my understanding into this particular project.

    I am 100% sure if someone can tell me sequential technical detail about how to successfully buffer one single frame from this evaluation board's jumper pins (480p format for example), every documentations will make sense for me afterwards.

    For me theoretical explanations do not make sens until a practical experimentation.


    Yes, PoornimaSubramani my company want to purchase one of this boards if i will tell them i can manage to accomplish this project.

    I just want someone to explain me the sequential states of the jumper pins for a one single frame period (For any video format).

    Thank you!

  • 1) I'd configure the the ADV7612 for the format you want to capture

    2) With the FPGA I'd wait for a Vsync pulse

    3) DE will stay high for one line of active video, capture the line, when DE goes low get ready to capture the next line of video when DE goes high again.

    4) Continue capturing video lines when DE is high unti Vsync goes high.  That would complete one frame of video.

    For the jumpers the controls linles you would be interested in are DE and VS

    The CLK line is the pixel rate used to capture the data.

    Once you get a board, Configure the ADV7612 and scope probe the jumper pins.  It should all become clear then.

  • Thank you very much GuenterL for your answer

  • This question has been assumed as answered either offline via email or with a multi-part answer. This question has now been closed out. If you have an inquiry related to this topic please post a new question in the applicable product forum.

    Thank you,
    EZ Admin
  • Hello,

    I am writing after a long time. I hope I can reach you. What did you do in your project? Did you succeed in capturing video and photos? Can you keep us informed of the latest developments? :)