From: "Németh Márton" <nm127@freemail.hu>
To: Thomas Kaiser <thomas@kaiser-linux.li>,
Jean-Francois Moine <moinejf@free.fr>,
Luc Saillard <luc@saillard.org>
Cc: "V4L Mailing List" <linux-media@vger.kernel.org>,
"Németh Márton" <nm127@freemail.hu>
Subject: Re: image quality of Labtec Webcam 2200
Date: Fri, 11 Sep 2009 20:17:51 +0200 [thread overview]
Message-ID: <4AAA944F.1090701@freemail.hu> (raw)
In-Reply-To: <4AA9F7A0.5080802@freemail.hu>
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
next prev parent reply other threads:[~2009-09-11 18:17 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-11 7:09 image quality of Labtec Webcam 2200 Németh Márton
2009-09-11 18:17 ` Németh Márton [this message]
2009-09-12 0:43 ` leandro Costantino
2009-09-12 1:21 ` leandro Costantino
[not found] ` <c2fe070d0909111741l21120025v3f45eb8566d27c7a@mail.gmail.com>
[not found] ` <4AAB3CB5.7090106@freemail.hu>
2009-09-12 14:51 ` leandro Costantino
2009-09-12 18:26 ` Németh Márton
2009-09-13 7:20 ` Jean-Francois Moine
2009-09-13 11:00 ` Németh Márton
2009-09-13 14:42 ` leandro Costantino
2009-09-13 15:59 ` Thomas Kaiser
2009-09-13 18:50 ` Hans de Goede
2009-09-13 18:48 ` Hans de Goede
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