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View Full Version : Phone camera quality - photo good, video bad


blubb444
13th December 2012, 01:41
(First off, I don't know if this is the right forum or even site to post in, but I think there are lots of people with the necessary expertise here to clear the issue. After a dozen of searches, Google couldn't help me so it's either just me having that issue or others don't care.)
So I finally got myself a smart phone (Huawei U9200) running Android 4.0.3. Of course I don't expect wonders from it when it comes to the camera quality but there's a huge discrepancy between video and photo quality. The camera is officially rated at 8MP (4:3, 3248x2436). While I don't know if it really has that many independent pixels, it sure has more than enough enough for Full HD (1440x1080 in 4:3) when I'm taking photos with the right lighting and in a stable position. The full image looks very sharp on my 1920x1080 screen and it still looks acceptably sharp when I look at it in 1:1 pixel mode (a.k.a. "100% zoom"/"original size", I'm using IrfanView) Sample image:
http://www.file-upload.net/download-6921925/IMG_20121207_230657.jpg.html (pay attention to the left part of the shadow of the glass)
But here comes the problem: When I'm recording a video in 1920x1080 mode, it looks like it was nearest-neighbour-resized from the original 8MP to 640x480, then cropped to 640x360, blown up to 1920x1080 (bilinear, bicubic or something like that) and finally some strange chromatic aberration added, sample video:
http://www.file-upload.net/download-6921929/VID_20121212_161655.mp4.html (pay attention to the twigs on the left side)
It really looks like every third pixel repeats and I get nearly the same effect (minus the chromatic aberration) when I take a video from my proper HD cam (Panasonic HDC-TM700), load it up in AviSynth, PointResize(640,360) then BicubicResize(1920,1080).
I first thought this was a problem of the stock camera app, but then I installed another one (CameraMX) and it looks exactly the same. That's why I'm thinking that those apps somehow call a pre-defined hardware function which does that NN-resizing, probably because (it's assumed) that it's too CPU-intensive to do a proper resizing from the original 8MP. If that's the case, is it possible to do it in a "software way", i.e. the software would just call the regular (good-looking) photo function 30x/second (or less/lower resolution if the CPU limits it) and then properly scale it to Full HD (or something lower)? Are there apps that do just that? There are a lot of camera apps floating around but they don't mention how exactly they record, I'd be willing to pay a couple €s for a properly working camera app, so if someone knows any, please tell (I don't want to pay for one or multiple apps just to find out that they output the same NN+Chroma AR crap).

Bleck
16th December 2012, 19:54
I had a hand-camera able to take huge pictures, but It recorded 340x240 video or something like that. I think is normal in every phone camera and low-tech cameras.

Asmodian
17th December 2012, 19:23
There could be a lot of reasons this is happening and there is more to capturing video than the sensor in the camera. You also need to encode it to some reasonable format (jpeg) and then save it to the flash memory. Often one of these steps is too slow to do the high frame rates video needs.

It sounds like one of these intermediate steps in your phone is much too slow for video so "shortcuts" are taken when recording video. This is probably part of the phones hardware/firmware and not controllable by the camera app. I have seen cell phone camera firmware updates as part of an OS update, you might see if there is anything for your phone but it is a long shot.

blubb444
22nd December 2012, 19:41
Well I have updated to the newest FW meanwhile and don't see much improvement, but at least the ugly Chroma AR seems to be gone when I choose 640x480 resolution (that could've been so before too), however it's still clearly NN scaled (lots of aliasing on sharp edges).
But it seems I'll have to live with it when it's done via firmware...

setarip_old
26th December 2012, 00:03
@blubb444

Phone cameras are great for the ability to grab unanticipated video. You really shouldn't expect too much in the way of quality - certainly nothing near the quality of a dedicated vid camera...

dadix
29th December 2012, 20:20
Search in internet about "lgcamera" - is a android camera application (with this you can change bitrate of codec up to 100 mbs and audio to 48.0 khz. They have free version and pro version.