Talk:Known problems

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Just noticed - all MJPEG versions of 333 code (at least from v 6.3.4) skip each other frame, so the actual fps is just 1/2 of that of the sensor. Theora version works fine, I also remember fixing that for the 313 cameras. And so far nobody (including me) noticed that (or at least told me).

I'll work full speed on this issue, it is most likely caused by missing interrupts.

--Andrey.filippov 19:10, 21 November 2005 (CST) Found it, will fix shortly. It was because only 2 extra lines were added to frame to accomodate 18x18tiles for 16x16 MCUs (how it was in 313), not 4 for 20x20 tiles. So compressor was waiting for the last 2 lines that came only with the new frame - too late.

So I'll test the fixed code, but still sensor driver need a complete rebuild - it is too messy by now after many modifications fro new sensors and cameras. So now period calculation is not correct when binning is used (and not all the data is in the Micron datasheet as actually binning works for up to 8, not just 3 as they write. We also need to make a cleaner driver as more sensors aree coming soon - and they will have different controls.

--Andrey.filippov 02:10, 22 November 2005 (CST)

Now it is gone --Andrey.filippov 03:57, 22 November 2005 (CST)

--User:Jmf 26 august 2006

3 pictures just to illustrate known problems of CMOS with binning
alt text
alt text
alt text

Vertical lines in binning mode

Yes, it is a known problem. The CMOS sensor in the camera is mounted upside-down, as the board benefited from the fact that 1-2-3MPix sensors by Micron are pin-compatible. The board was designed for 1.3MPix MT9M001 that did have flip-x and flip-y features (as most other CMOS sensors) so there was no problems to mount the sensor 180 degrees - I was just optimizing the PCB layout. In 3MPix sensors these mirroring features where dropped (at least from the datasheet available online on their web site). Fortunately it turned out that it is possible to mirror images (I just tried undocumented bits in different registers), but horizontal binning with horizontal flip (default) does not work.

Quick fix - turn the camera upside-down and unselect mirroring.

--Andrey.filippov 12:42, 26 August 2006 (CDT)

That problem (only for 3MPix sensors, 5 Mpix did not have it) is fixed in the current code of the 353 camera --Andrey.filippov 23:02, 25 January 2011 (UTC)