Do I spot a pattern here? We know the Gemini SP5509 is a 5MP camera module, as advertised. Yet, NO photo I have taken with it, has seemed to contain anywhere near 5MP worth of actual detail. In some thread, I think we even half joked that perhaps they were, by mistake, capturing, and interpolating, a frame from the viewfinder video stream, which would likely be 1440x1080, as the display is 1080 pixels tall and the sensor has a 4:3 aspect ratio.
What if... it is, actually,
worse? What if the default behavior of the "MediaTek Camera Application", which appears in the EXIF for Gemini rear camera photos too, for whatever silly reason, is to demosaic by clumping photosites together 2x2 and then interpolate back up to the advertised resolution? It would be CPU-friendly for sure, so it would reasonably be decently fast even on really low end hardware. It could perhaps be a factory fallback default, that the device maker is supposed to change.
That would give 24MP Cosmo photos 6MP worth of details, stretched back to 24MP and Gemini photos 1.25MP (1280x960) worth of details, stretched back to 5MP. It would be really bonkers, but it does kind of match the amount of detail that seems to come out of the Gemini rear camera.
In [a href=\'index.php?showtopic=35308\']this post[/a], I posted a photo of a page of text, from Gemini rear camera. I repeated my experiment with that picture today, reducing it to 50%, both ways, which, thanks to the crude code in Windows MS-paint, throws away half the pixels, both ways. Then I zoomed it to 200%, and - again - apparently NO detail was lost... The reduced and zoomed in picture was, to me,
exactly as readable as the 5MP image. If anything, the processed image felt less objectionable, as it was fairly sharp and detailed, for a 1.25MP image, that is, while the 5MP image feels a tad out of focus.
Here's a composite example: (please click to see all the pixels)
Never mind the language (it's a fragment of an article about a local toy store). The left half is a completely unprocessed crop from the Gemini rear camera, warts and all. The right half, has been shrunk down, by throwing away every other pixel, both ways, and then scaled back by doubling the remaining pixels both ways. I saved it as a PNG, so I've added no other artifacts. No, they're not identical. The technically inclined can subtract one half of the image from the other and the result won't be completely black, but with the naked eye, can you spot ANY difference in the amount of detail?
I'm getting that sinking feeling in my stomach, that I might, regretfully, be on to something here... They shouldn't be THAT similar, lest the left half was created by stretching something that was half the resolution to begin with... On the other hand, maybe this suggests the SP5509 isn't QUITE as bad as we all think. Maybe it's just really craptastic image processing, that turns it into a glorified 1.25MP camera. Maybe, in theory, it would somehow be possible to get somewhat better pictures out of the SP5509 and, by extension, out of whatever module the Cosmo is using?