ADSP BF609 Processor interfacing SD card timing issue

Hi,

            I am trying to interface sd card with RSI controller in adsp bf609.SD card interfacing is going fine....writing and reading the image data from SD card is done..My application is taking input source from video decoder with frame rate of 25MHZ,resolution 720*576.Every incoming frame within 40ms should be stored in SD card but it is taking 196ms for each frame to be stored in SD card.Can anyone please suggest me how to reduce the timing for each frame to store in SD card.

Thanks and Regards,

Jyothsna Sagili.