ios - GPU Image : Best resolution with Higher FPS -

i using gpu framework, record videos.

@property (nonatomic, strong) gpuimagestillcamera *stillcamera; 

i setting property changes resolution , fps.

self.stillcamera.capturesession.sessionpreset = avcapturesessionpresethigh; 

on iphone6, 6+ , iphone5s getting 1920*1080 30fps.

for ipod5th generation , iphone5, i need 24fps 1920*1080 resolution, same native camera app. getting 8-9fps 1920*1080 resolution.

i have tried value avcapturesessionpreset1920x1080 well.

i have tried,

[self.stillcamera.inputcamera lockforconfiguration:nil];  self.stillcamera.inputcamera.activevideominframeduration = cmtimemake(1, 24); self.stillcamera.inputcamera.activevideomaxframeduration = cmtimemake(1, 24); [self.stillcamera.inputcamera unlockforconfiguration]; 

but not affecting when using self.stillcamera.capturesession.sessionpreset = avcapturesessionpresethigh;

i have tried,

[self.stillcamera setframerate:24]; 

this not working self.stillcamera.capturesession.sessionpreset = avcapturesessionpresethigh;

i have tried function [self configurecameraforhighestframerate:self.stillcamera.inputcamera];as well, apple documentation https://developer.apple.com/library/mac/documentation/avfoundation/reference/avcapturedevice_class/index.html getting fps near 18, 1280*720 resolution,

i need 1920*1080 24fps, on ipod5th , iphone5. please me.

you appriciated. in advance.