Márton Németh wrote: > Hi, > > I have a Labtec Webcam 2200 and I have problems with the image quality > with Linux 2.6.31 + libv4l 0.6.1. I made some experiments and stored > each captured image as raw data and when libv4l was able to convert > then I also stored the result as bmp. > > You can find my results at http://v4l-test.sourceforge.net/results/test-20090911/index.html > There are three types of problems: > a) Sometimes the picture contains a 8x8 pixel error, like in image #9 > http://v4l-test.sourceforge.net/results/test-20090911/index.html#img00009 > b) Sometimes the brightness of the half picture is changed, like in > images #7, #36 and #37 > http://v4l-test.sourceforge.net/results/test-20090911/index.html#img00007 > http://v4l-test.sourceforge.net/results/test-20090911/index.html#img00036 > http://v4l-test.sourceforge.net/results/test-20090911/index.html#img00037 > c) Sometimes the libv4l cannot convert the raw image and the errno > is set to EAGAIN (11), for example image #1, #2 and #3 > > Do you know how can I fix these problems? I investigated the c) point a little bit. When I get a negative return value from the v4lconvert_convert() function then I print out the error message what the v4lconvert_get_error_message() function returns. With the result log file I executed a "grep v4l-convert |sort |uniq" command. All the error messages are coming from the tinyjpeg.c (Small jpeg decoder library): v4l-convert: error decompressing JPEG: error: more then 63 AC components (65) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (66) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (67) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (68) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (69) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (70) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (71) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (72) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (73) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (75) in huffman unit v4l-convert: error decompressing JPEG: error: more then 63 AC components (76) in huffman unit v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x00 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x01 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x02 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x04 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x08 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x09 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x0a v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x10 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x12 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x14 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x1a v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x1b v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x1c v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x1f v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x80 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x82 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x87 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x88 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x89 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x8a v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x8b v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x8c v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x8d v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x8e v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x8f v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x90 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x91 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x92 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x93 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x94 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x95 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x96 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x97 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x99 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x9b v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x9c v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x9d v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x9e v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0x9f v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xa3 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xa5 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xa6 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xa7 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xa9 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xaa v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xab v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xad v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xaf v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xb3 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xb5 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xb7 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xb8 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xb9 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xbc v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xbd v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xbe v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xbf v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xc0 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xc4 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xc6 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xc7 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xc9 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xcb v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xcc v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xcf v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xd1 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xd2 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xd3 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xd4 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xdc v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xdf v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xe5 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xe7 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xe8 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xea v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xeb v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xec v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xf0 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xf2 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xf4 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xf5 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xf8 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xf9 v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xfa v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xfc v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xfe v4l-convert: error decompressing JPEG: Pixart JPEG error: invalid MCU marker: 0xff v4l-convert: error decompressing JPEG: Pixart JPEG error, stream does not end with EOF marker v4l-convert: error decompressing JPEG: unknown huffman code: 0000ff81 v4l-convert: error decompressing JPEG: unknown huffman code: 0000ffec v4l-convert: error decompressing JPEG: unknown huffman code: 0000ffff 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
