nemesis <nam### [at] gmailcom> wrote:
> light_source { 3*<1,3,1> 1 area_light x,z,2,2 adaptive 0 jitter }

  That reminds me of a conversation I had in another forum where someone
basically made the claim that if you double the resolution of a video (in
both axes, making each frame have 4 times as many pixels), encoding it to
x264 would require four times as much bitrate in order to preserve the same
quality as the original (because, you know, four times as many pixels equal
four times the needed bitrate).

  I countered that in my experience scaling up the video and then encoding
it requires next to no upscaling of the bitrate in order to preserve the
same visual quality. (Claiming that quadrupling the amount of pixels would
require quadruple amount of bitrate is as silly as claiming that quadrupling
the size of a text file would make it compress to four times the size of the
original text file compressed.)

  He was determined to prove me wrong, so he took an original 256x192 pixels
video (showing gameplay of a console game) and scaled it up to 1600x1200
and encoded it to x264 with the same bitrate (and seemingly without
fine-tuning any other parameters). The end result had slightly more visual
artifacts than the original.

  The original question was whether it would be possible to double the
resolution of the video without enlarging file size, and he "proved" my
affirmative allegation wrong by taking a video and making it over *six*
times larger, resulting in *slightly* more visual artifacts.

  (Amusingly, while he tried to prove my allegation wrong, he inadvertedly
also succeeded in proving wrong the allegation that doubling the video
resolution would require four times as much bitrate to preserve the same
visual quality. He made the video over six times larger and with the same
bitrate there were only slightly more visual artifacts.)

-- 
                                                          - Warp

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