- SN9C10x PC Camera Controllers
- Driver for Linux
- =============================
+ SN9C10x PC Camera Controllers
+ Driver for Linux
+ =============================
- - Documentation -
+ - Documentation -
Index
development of this project, despite several requests for enough detailed
specifications of the register tables, compression engine and video data format
of the above chips. Nevertheless, these informations are no longer necessary,
-becouse all the aspects related to these chips are known and have been
+because all the aspects related to these chips are known and have been
described in detail in this documentation.
The driver relies on the Video4Linux2 and USB core modules. It has been
high compression quality (see also "Notes for V4L2 application developers"
and "Video frame formats" paragraphs);
- full support for the capabilities of many of the possible image sensors that
- can be connected to the SN9C10x bridges, including, for istance, red, green,
+ can be connected to the SN9C10x bridges, including, for instance, red, green,
blue and global gain adjustments and exposure (see "Supported devices"
paragraph for details);
- use of default color settings for sunlight conditions;
-------------------------------------------------------------------------------
Name: video_nr
Type: short array (min = 0, max = 64)
-Syntax: <-1|n[,...]>
+Syntax: <-1|n[,...]>
Description: Specify V4L2 minor mode number:
- -1 = use next available
- n = use minor number n
- You can specify up to 64 cameras this way.
- For example:
- video_nr=-1,2,-1 would assign minor number 2 to the second
- recognized camera and use auto for the first one and for every
- other camera.
+ -1 = use next available
+ n = use minor number n
+ You can specify up to 64 cameras this way.
+ For example:
+ video_nr=-1,2,-1 would assign minor number 2 to the second
+ recognized camera and use auto for the first one and for every
+ other camera.
Default: -1
-------------------------------------------------------------------------------
Name: force_munmap
Type: bool array (min = 0, max = 64)
-Syntax: <0|1[,...]>
+Syntax: <0|1[,...]>
Description: Force the application to unmap previously mapped buffer memory
- before calling any VIDIOC_S_CROP or VIDIOC_S_FMT ioctl's. Not
- all the applications support this feature. This parameter is
- specific for each detected camera.
- 0 = do not force memory unmapping
- 1 = force memory unmapping (save memory)
+ before calling any VIDIOC_S_CROP or VIDIOC_S_FMT ioctl's. Not
+ all the applications support this feature. This parameter is
+ specific for each detected camera.
+ 0 = do not force memory unmapping
+ 1 = force memory unmapping (save memory)
Default: 0
-------------------------------------------------------------------------------
+Name: frame_timeout
+Type: uint array (min = 0, max = 64)
+Syntax: <n[,...]>
+Description: Timeout for a video frame in seconds. This parameter is
+ specific for each detected camera. This parameter can be
+ changed at runtime thanks to the /sys filesystem interface.
+Default: 2
+-------------------------------------------------------------------------------
Name: debug
Type: ushort
-Syntax: <n>
+Syntax: <n>
Description: Debugging information level, from 0 to 3:
- 0 = none (use carefully)
- 1 = critical errors
- 2 = significant informations
- 3 = more verbose messages
- Level 3 is useful for testing only, when only one device
- is used. It also shows some more informations about the
- hardware being detected. This parameter can be changed at
- runtime thanks to the /sys filesystem interface.
+ 0 = none (use carefully)
+ 1 = critical errors
+ 2 = significant informations
+ 3 = more verbose messages
+ Level 3 is useful for testing only, when only one device
+ is used. It also shows some more informations about the
+ hardware being detected. This parameter can be changed at
+ runtime thanks to the /sys filesystem interface.
Default: 2
-------------------------------------------------------------------------------
frame header of the most recent requested and captured video frame. The header
is always 18-bytes long and is appended to every video frame by the SN9C10x
controllers. As an example, this additional information can be used by the user
-application for implementing auto-exposure features via software.
+application for implementing auto-exposure features via software.
The following table describes the frame header:
0x04 0xC4 Frame synchronisation pattern.
0x05 0x96 Frame synchronisation pattern.
0x06 0xXX Unknown meaning. The exact value depends on the chip;
- possible values are 0x00, 0x01 and 0x20.
+ possible values are 0x00, 0x01 and 0x20.
0x07 0xXX Variable value, whose bits are ff00uzzc, where ff is a
- frame counter, u is unknown, zz is a size indicator
- (00 = VGA, 01 = SIF, 10 = QSIF) and c stands for
- "compression enabled" (1 = yes, 0 = no).
+ frame counter, u is unknown, zz is a size indicator
+ (00 = VGA, 01 = SIF, 10 = QSIF) and c stands for
+ "compression enabled" (1 = yes, 0 = no).
0x08 0xXX Brightness sum inside Auto-Exposure area (low-byte).
0x09 0xXX Brightness sum inside Auto-Exposure area (high-byte).
- For a pure white image, this number will be equal to 500
- times the area of the specified AE area. For images
- that are not pure white, the value scales down according
- to relative whiteness.
+ For a pure white image, this number will be equal to 500
+ times the area of the specified AE area. For images
+ that are not pure white, the value scales down according
+ to relative whiteness.
0x0A 0xXX Brightness sum outside Auto-Exposure area (low-byte).
0x0B 0xXX Brightness sum outside Auto-Exposure area (high-byte).
- For a pure white image, this number will be equal to 125
- times the area outside of the specified AE area. For
- images that are not pure white, the value scales down
- according to relative whiteness.
- according to relative whiteness.
+ For a pure white image, this number will be equal to 125
+ times the area outside of the specified AE area. For
+ images that are not pure white, the value scales down
+ according to relative whiteness.
+ according to relative whiteness.
The following bytes are used by the SN9C103 bridge only:
--------- ----------
0x0c45 0x6001
0x0c45 0x6005
+0x0c45 0x6007
0x0c45 0x6009
0x0c45 0x600d
0x0c45 0x6024
MI-0343 Micron Technology, Inc.
OV7630 OmniVision Technologies, Inc.
PAS106B PixArt Imaging, Inc.
+PAS202BCA PixArt Imaging, Inc.
PAS202BCB PixArt Imaging, Inc.
TAS5110C1B Taiwan Advanced Sensor Corporation
TAS5130D1B Taiwan Advanced Sensor Corporation
value and is disposed in memory according to the pattern shown below:
B[0] G[1] B[2] G[3] ... B[m-2] G[m-1]
-G[m] R[m+1] G[m+2] R[m+2] ... G[2m-2] R[2m-1]
+G[m] R[m+1] G[m+2] R[m+2] ... G[2m-2] R[2m-1]
...
... B[(n-1)(m-2)] G[(n-1)(m-1)]
... G[n(m-2)] R[n(m-1)]
The algorithm purely describes the conversion from compressed Bayer code used
in the SN9C10x chips to uncompressed Bayer. Additional steps are required to
convert this to a color image (i.e. a color interpolation algorithm).
-
+
The following Huffman codes have been found:
-0: +0 (relative to reference pixel value)
+0: +0 (relative to reference pixel value)
100: +4
101: -4?
-1110xxxx: set absolute value to xxxx.0000
+1110xxxx: set absolute value to xxxx.0000
1101: +11
1111: -11
11001: +20
order):
- Luca Capello for the donation of a webcam;
+- Philippe Coval for having helped testing the PAS202BCA image sensor;
- Joao Rodrigo Fuzaro, Joao Limirio, Claudio Filho and Caio Begotti for the
donation of a webcam;
- Jon Hollstrom for the donation of a webcam;