Writing to SD card faster FPS


I’m using the H7 plus and following the “image_writer” example to save raw file to sd card. Is there anyway to increase write speed at full resolution ( at least VGA) to increase the FPS achieved ? Due to the high pixel-resolution requirements in my use case I cannot do binning and would like to retain best resolution possible ( at least VGA when using OV7725). Currently, only by windowing to around 256x256 I’m getting close to 30 FPS. When doing VGA (full-resolution ) it drops to 20 FPS. Even though, the typical FPS with H7 plus and OV7725 on simple “helloworld” I get is 60 FPS.

Is there any workaround to increase the FPS for writing to sd card in VGA resolution? It would be a great feature to have this.

I was thinking on-the lines of possibility of using Interrupts to write to sd-card, by saving stream buffer in RAM and subsequently clearing buffer and again writing to sd-card with Interrupts, to get constant (stable) and high-fps .



It’s just requires us to implement double buffering support. I will have this feature in before the end of the year. However, I have to get a new screen interface working before to enable the H7 to drive monitors.

Hi Nyamekye,

As a follow-up to my previous question, can we expect the improved FPS and more stable “image_writer” write speed to sd-card support feature to roll-out soon ? I’m really looking for forward to it and in need of this feature.


I have to update the FIR driver subsystem for the OpenMV Cam Pure Thermal. Once I finish that I will work on adding triple/many buffer support for the camera. This will finally let everyone do smooth video record and make the system run faster at maximum processor utilization.

Great, Thanks a lot for your continuous support !