Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

Get image from frame

I am working on a project and need to process image frames acquainted before it goes to display. From the VIP Camera example, I found this:

display = alt_video_display_only_frame_init(// ALT_VIDEO_DISPLAY_SGDMA_NAME, // char* sgdma_name

FRAME_BUF_W, // int width

FRAME_BUF_H, // int height

ALT_VIDEO_DISPLAY_COLOR_DEPTH, // int color_depth

SDRAM_BASE + 0x00800000, // int buffer_location

1 ); // int num_buffers

I wish to process the image obtained in 3D arrays(R,G,B ) but I have difficulty extracting the values from "display" and also how to put back the processed image into "display". Can someone help to guide me? I am quite new in NIOS II, is there any documentation or guide on this alt_video_display library?

Thank You

2 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    13 years ago

    --- Quote Start ---

    Check: http://www.altera.com/literature/an/an527.pdf (http://www.altera.com/literature/an/an527.pdf)

    All of the functions (as far as I can tell) are listed there as well as descriptions for each function.

    --- Quote End ---

    Thank You for the link. It was certainly helpful but I still quite confuse with this function:

    ========

    int alt_video_display_buffer_is_available(alt_video_display* display);

    This function returns the next free frame buffer available for display. The

    function returns a condition code of 0 if an empty buffer is found; any

    other return value indicates failure. The function accepts the following

    parameter:

    ■ display: This variable is a pointer to a data structure that keeps

    track of all of the frame buffer information, including the start

    addresses for all of the frame buffers.

    ========

    It says that it return 0 or other number indicates failure. Then, my question is, where is the frame I want goes? I need the frame to do analysis before display. Thank you.