This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMS320DM8127: for Dm8127, why cpu access a tiler memory buffer (720*1280) with virtual-cpu address will give a more low performance

Part Number: TMS320DM8127

Hi all. We have a requirement for a 90 rotation on dm8127. this main processing path as below: 1. Sensor->ISS(1280*720)->output tiler with rotated 90,so the output buffer is 720*1280 2. for captured input 720*1280 buffer ->do image process alg->still output 720*1280 3. use hdvpss->LCD(720*1280) now we have a performance issue about access tiler memory for our alg. In our alg when cpu access a linearly line(720 data) with the 90 tiler memory address who is a cpu_viraddress from a tiled address, but in really, the data is not linearly stored in SDRM/DDR, is that right? so we think. when this access will miss cache, so this is the main reason lead to a low performance. so what is the purpose of tiler except rotated, is only giva a high performance for macro-process, such as video encode/decode? OC, we also want to know how to make VPSS do a 90 rotation, is there any app or demo to be reference, maybe this a more simple way? in our RDK, I can't find any demo about using vpss to act a rotation.

  • Hi all.
    We have a requirement for a 90 rotation on dm8127.
    this main processing path as below:
    1. Sensor->ISS(1280*720)->output tiler with rotated 90,so the output buffer is 720*1280
    2. for captured input 720*1280 buffer ->do image process alg->still output 720*1280
    3. use hdvpss->LCD(720*1280)
    now we have a performance issue about access tiler memory for our alg.
    In our alg when cpu access a linearly line(720 data) with the 90 tiler memory address who is a cpu_viraddress from a tiled address, but in really, the data is not linearly stored in SDRM/DDR, is that right?
    so we think. when this access will miss cache, so this is the main reason lead to a low performance. so what is the purpose of tiler except rotated, is only giva a high performance for macro-process, such as video encode/decode?
    OC, we also want to know how to make VPSS do a 90 rotation, is there any app or demo to be reference, maybe this a more simple way?
    in our RDK, I can't find any demo about using vpss to act a rotation.
  • I will notify the IPNC RDK team for help.

    Regards,
    Pavel