enhancement: multi-resolution stream SSIM/PSNR value calculation about vaapi-fits HOT 5 CLOSED

Same question as in #14 (comment)

from vaapi-fits.

for gstreamer decoding, the input stream is mul-resolution, the output should be mul-resolution too, so to calculate the output ssim, we should support multi-resolution stream SSIM value calculation.
for example:
gst-launch-1.0 -vf filesrc location=./input_mul_res.mpeg2 ! mpegvideoparse ! vaapimpeg2dec ! videoconvert ! vaapisink

we can set case as below, I will implement it later.
mul_res = [(width1, height1, frame1), (width2, height2, frame2),...]

function:

for i in mul_res:
  for j in range(i[2]):
    ...
    ...

from vaapi-fits.

for psnr, the encoded file is specified as NxM resolution in general, so we can ignore multi-resolution psnr calculation at now.

from vaapi-fits.

@uartie can you help have a review about #24

from vaapi-fits.

now gstreamer add parse "videoscale" to make the output as single resolution, so no need multi-res ssim support, close it

from vaapi-fits.