According to sources from SamMobile, Samsung's next-generation flagship, the Galaxy S6, along with its cousin the Galaxy S6 Edge, will use Samsung's own 20MP sensor on the back, as well as the 5MP front-facing camera that was used in the Galaxy Alpha last year.
Samsung started using its own sensor at the high-end last year in the Galaxy S5, although from most reports it performed slightly worse than the Sony camera inside the Galaxy Note 4. It seems Samsung wants to try again, but this time with a 20MP sensor rather than a 16MP one.
The new camera will also get Optical Image Stabilization, according to the rumor. Although OIS has been embraced more quickly by other companies, Samsung has been one of the laggards in this area. OIS is an important camera component because it's highly effective against camera shake, which also makes the device better at capturing images in lower-light environments.
It's not clear yet whether Samsung itself will provide the 20MP module for both the Galaxy S6 and the Galaxy S6 Edge. There could be supply issues that could impede the adoption in the Galaxy S6, although even if that's the case, Samsung could probably source a 20MP sensor from Sony.
Samsung has used Sony's sensors in most of its flagships so far, and Sony has been putting 20MP cameras in its own devices for some time now, so there shouldn't be any 20MP camera shortages.
Late last year Sony announced a new 20MP sensor that has 192 focus points, but it's not clear whether that camera will arrive in time for the Galaxy S6 or if Sony will even give other companies early access to it. Sony may prefer using that sensor in its Xperia Z4 or future flagship smartphones of its own. On the other hand, Sony isn't doing so well financially right now, so it could sell that camera to Samsung if the company wants it.
Such high resolution cameras can bring much more details to pictures, but that comes to the detriment of image processing and low-light performance. Lower resolution cameras tend to do better in low-light, and image processing is also much faster because the processor has to deal with much less data. It will be interesting to see how Samsung deals with the processing of 20MP pictures. There haven't been too many complaints about Sony's phones, and chips have gotten even faster since then, which should make image processing quicker.
According to the new rumors, Samsung will also take full advantage of the overhauled camera APIs in Android 5.0 by introducing a "Pro" mode for its camera app. The Pro mode will allow users to choose between three focus modes, including a manual mode. Lollipop has also enabled the ability to save images in the non-compressed RAW format, and the Galaxy S6 camera app is likely to support the feature as well.
The Galaxy S6 and Galaxy S6 Edge are expected to be officially unveiled in March.