Hi Laurent, Laurent Pinchart wrote on 2013-06-18: >> If I use omap3isp-live to capture a stream on my beagleboard, the first >> time I start the app, the picture has always a green taint. The second >> time I start the app, the picture is good. As the camera is reset by a >> gpio upon device open, probably the CCDC or previewer is not >> initialized correctly? @Laurent: As I am unable to test it with another >> cam, does this also happen with your hardware or is it a problem >> specific to the mt9p031? > > Last time I've tested my MT9P031 sensor with the Beagleboard-xM there > was no such issue. If I test it with yavta, it works also from the very first start. So there must be an issue in my (adapted) omap3-isp-live. > >> The second problem is similiar to your problem: >> omap3isp-live has (thanks to Laurent) a built in snapshot-mode. So I >> am doing the following: >> 1. Streaming video, picture looks good on the second start 2. Taking a >> snapshot: The video stream will turn off, the isp-pipe reconfigured. >> Then the stream will be turned back on and the captured image will be >> written to memory. >> 3. The captured image will now be displayed, but the image is corrupted: >> Wrong colors and cut in half: >> https://www.dropbox.com/s/ijk1nq8nrhlobfd/bad-snapshot.jpg >> 4. It doesn't help to skip a few buffers, also the 3rd buffer looks bad. >> 5. Additional problem: The CCDC can't be stopped properly (omap3isp >> omap3isp: Unable to stop OMAP3 ISP CCDC) and sometimes the isp locks >> up completely. >> >>> So I used the register 0x0B (Restart), bit 0 (abandon the current >>> frame and restart from the first row) set to 1 each time the >>> function s_stream is called. >> >> The finding so far: If I do a frame-restart (the register 0x0b on >> mt9p031) upon stream-on, the CCDC can be stopped properly and the >> snapshot looks pretty good. BUT the colors are still messed up. If I >> then switch to streaming again, the colors sometimes turn to good but >> sometimes the picture is purple tainted. @Andrei: What have you done to >> get good colors? The color problem goes away nearly completely, if I do a power-off and on in the mt9p031_s_stream function. It then happens only 1 out of 10 times. At least an improvement ;) I have the feeling, that the CCDC doesn't get all data on a stream restart and that causes a buffer corruption. Probably the sensor doesn't start outputting from the beginning (even with a frame restart). Any ideas on this? Regards, Florian -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
