Hi, On 11/08/2009 02:29 PM, Németh Márton wrote:
Hi, I have some problem that libv4l cannot decode all image coming from the Labtec Webcam 2200. There are some cases when no image at all can be decoded. This case can be reproduced always for example by setting the camera to test mode to produce a color test bar. The raw data arrives from the driver (41472 bytes, see attached) and v4lconvert_convert() returns -1 and the errno is set to EAGAIN. In this case the v4lconvert_get_error_message() reports the following error message: v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xff
See: libv4lconvert/tinyjpeg.c, lines 1611-1620 for some info on the magical byte pixart puts between Huffman data blocks. The 0xff value probably is normal for the test mode, so I would start with trying to change the MCU test to also except 0xff as a valid MCU marker Regards, hans
Steps to reproduce: 1. get 13327:19c0469c02c3 from http://linuxtv.org/hg/v4l-dvb/ 2. apply the patch http://www.spinics.net/lists/linux-media/msg11841.html 3. apply the patch http://www.spinics.net/lists/linux-media/msg11842.html 4. compile and install the new driver 5. plug Labtec Webcam 2200 6. start capturing 7. execute "v4l2-dbg --set-register=0x72 9", this will switch on the color test card of the webcam. Current result: v4lconvert_convert() always return -1 and errno is EAGAIN until the olor test card is not switched off with "v4l2-dbg --set-register=0x72 0". How would you start to fix this? Regards, Márton Németh
-- 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
