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DLP2010EVM-LC: Input lag

Part Number: DLP2010EVM-LC

Dear TI support

Hello.

I'm looking for a DLP device with high response speed.

I read this document (TI Designs: TIDA-01474) which says DLP470NE runs 120Hz with 1-frame latency.

I also see that DLP2010EVM-LC is designed for high-speed applications. 

Can you tell me which has less input lag? 

I want to reduce the amount of time it takes for input signal to be displayed on the screen.

Thank you.

Kawakami

  • Hi Kotomi,

    Welcome to the TI E2E forums and thank you for your interest in DLP.

    I will look into this and get back to you soon.

    Thank you,

    Chris

  • Hi Kotomi,

    What is the type of application that you are interested in? Is it a display application or Light Control application?

    If it's Light Control application  - assuming that you want to display patterns using external pattern mode - the latency of the pattern display, in this case, will be equal to 1 vsync period.

    Regards,

    Mayank

  • Thank you for your rapid reply.

    What we are planning is to connect a camera directry to the DLP and display video iamges taken by the camera in real-time (with as little delay as possible).

    I suppose DLPs are designed to project RGB888 images.

    Could you tell me whether the framerate is reduced by 1/3 if the video images are captured in 8-bit grayscale (because identical three grayscale images are processed)?

    Or conversely, is there a way to increase framerate threefold? (for example, by making 1 frame of image with three grayscale images)

    I also want to know if grayscale images can be binarized in the settings of GUI or by writting command scripts.

    Thank you.

  • Kotomi-san,

    The DLPC3470 (the controller used with this EVM) supports 8-bit and 1-bit monochrome or RGB patterns in external pattern streaming mode. In these modes, the RGB888 bus used for parallel video is repurposed to transmit the 8-bit or 1-bit monochrome RGB patterns at 120Hz video framerate. In 8-bit mode, for example, this results in an effective framerate of 360Hz for your patterns.

    For more information about configuring the external pattern streaming mode see section 8.3.1.1 in the DLPC3470 datasheet:

    https://www.ti.com/lit/ds/symlink/dlpc3470.pdf

    I hope this helps.


    Regards,

    Philippe Dollo

  • Thank you Mr Dollo,

    Let me confirm my understanding.

    When 8-bit grayscale video images sent from a camera which runs at 120Hz are received, the DLP displays 3 identical images in 1/120 second.
    Am I correct?

    Let me ask one more question.
    Can I convert bit depth of the video images from 8 bit to 1 bit through the GUI?
    I want to binarize grayscale video images which is directly sent from a camera without using an external device.

    Thank you.
    Kotomi Kawakami

  • Kotomi-san,

    Please refer to my below responses - 

    When 8-bit grayscale video images sent from a camera that runs at 120Hz are received, the DLP displays 3 identical images in 1/120 second.
    Am I correct?

    >> Yes, given that you have configured the DLPC to display 8-bit external patterns.

    Can I convert bit depth of the video images from 8 bit to 1 bit through the GUI? 

    >> Yes. if your input frame is an 8-bit pattern - you can display each bit of the pattern with equal timings by configuring the DLPC in external pattern mode to display 1-bit patterns with patterns per frame as 8.

    Regards,

    Mayank

  • Thank you for your replay.

    Please bear with me if I'm wrong.

    For your second response, do you mean that displaying each bit of the pattern is splitting 8-bit-datum into 8 1-bit data?

    What I'm wandering is if it's possible to convert a grayscale image into a binary black-and-white image and display it for example 24 times in a frame (24 doesn't matter though).

    It would be very helpful if you could provide the way to set threshold value for binarization and also run-time for the image processing.

    Thank you,

    Kotomi Kawakami

  • Kotomi-san,

    Please refer to my below responses - 

    1. For your second response, do you mean that displaying each bit of the pattern is splitting 8-bit-datum into 8 1-bit data?

    >> Yes. The below image is an example of how you can configure the external pattern mode to do the same.

    The DLPC will simply convert the input frame into multiple 1-bit patterns as mentioned in the above example. Suppose you want to convert a 24bit frame into 24 1 bit patterns, then you will change the Patterns per frame input parameter as 24.

    I hope this answers all your queries.

    Regards,

    Mayank

     

  • Thank you Mr  Khandelwal,

    Would it be possible to access the video processing functions to edit its source code?

    Thank you,

    Kotomi Kawakami

  • Kotomi-san,

    As this is a closed system, the source code is not open and hence you will not be able to edit it.

    One more point to add - 

    Since external pattern mode is a Light Control mode hence nearly all the video processing blocks of the ASIC are disabled during this mode in order to display the patterns with maximum pixel-level accuracy as possible.

    Regards,

    Mayank