Resize frame and read image

Hi All,

I am working on upscaling image 2x,3x,4x etc by applying video effects from a plug-in. I am able read image data from host and upscale the content.

Now I am investigating to display upscaled content on Premiere Po. 

Use case:

1.Open Premiere Pro and open an image file.

2. Select timeline-> Sequence Settings->Change frame size.

Pseudocode: 

static
PF_Err
Render(
PF_InData *in_data,
PF_OutData *out_data,
PF_ParamDef *params[],
PF_LayerDef *outputP)
{
AEGP_SuiteHandler suites(in_data->pica_basicP);
PF_Err err = PF_Err_NONE;
PF_EffectWorld *input = &params[0]->u.ld;
PF_COPY(input, outputP, NULL, NULL); 

If I am trying to read input image using PF_EffectWorld *input = &params[0]->u.ld;, it gives resized frame but the requirement is to read original image data after resizing.

ex. Open a 1920x1080 file.

resize frame to 3840x2160 (2x scale)

then read the original image.

Please suggest, how to read original image after resizing frame.

}

Thanks in advance.