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1
2 ***********************************************************
3 * EasyCAP USB 2.0 Video Adapter with Audio, Model DC60 *
4 * and *
5 * EasyCAP002 4-Channel USB 2.0 DVR *
6 ***********************************************************
7 Mike Thomas <rmthomas@sciolus.org>
8
9
10
11SUPPORTED HARDWARE
12------------------
13
14This driver is intended for use with hardware having USB ID 05e1:0408.
15Two kinds of EasyCAP have this USB ID, namely:
16
17 * EasyCAP USB 2.0 Video Adapter with Audio, Model DC60,
18 having input cables labelled CVBS, S-VIDEO, AUDIO(L), AUDIO(R)
19
20 * EasyCAP002 4-Channel USB 2.0 DVR, having input cables labelled
21 1, 2, 3, 4 and an unlabelled input cable for a microphone.
22
23
24BUILD OPTIONS AND DEPENDENCIES
25------------------------------
26
27Unless EASYCAP_DEBUG is defined during compilation it will not be possible
28to select a debug level at the time of module installation.
29
30If the parameter EASYCAP_IS_VIDEODEV_CLIENT is undefined during compilation
31the built module is entirely independent of the videodev module, and when
32the EasyCAP is physically plugged into a USB port the special files
33/dev/easycap0 and /dev/easysnd1 are created as video and sound sources
34respectively.
35
36If the parameter EASYCAP_IS_VIDEODEV_CLIENT is defined during compilation
37the built easycap module is configured to register with the videodev module,
38in which case the special files created when the EasyCAP is plugged in are
39/dev/video0 and /dev/easysnd0.
40
41During in-tree builds the following should should be defined whenever the
42parameter EASYCAP_IS_VIDEODEV_CLIENT is defined:
43
44EASYCAP_NEEDS_V4L2_DEVICE_H
45EASYCAP_NEEDS_V4L2_FOPS
46EASYCAP_NEEDS_UNLOCKED_IOCTL
47
48If the build is performed out-of-tree against older kernels the parameters
49to be defined depend on the kernel version in a way which will not be
50discussed here.
51
52
53KNOWN RUNTIME ISSUES
54--------------------
55
56(1) Intentionally, this driver will not stream material which is unambiguously
57identified by the hardware as copy-protected. Normal video output will be
58present for about a minute but will then freeze when this situation arises.
59
60(2) The controls for luminance, contrast, saturation, hue and volume may not
61always work properly.
62
63(3) Reduced-resolution S-Video seems to suffer from moire artefacts.
64
65
66INPUT NUMBERING
67---------------
68
69For the EasyCAP with S-VIDEO input cable the driver regards a request for
70inputs numbered 0 or 1 as referring to CVBS and a request for input
71numbered 5 as referring to S-VIDEO.
72
73For the EasyCAP with four CVBS inputs the driver expects to be asked for
74any one of inputs numbered 1,2,3,4. If input 0 is asked for, it is
75interpreted as input 1.
76
77
78MODULE PARAMETERS
79-----------------
80
81Three module parameters are defined:
82
83debug the easycap module is configured at diagnostic level n (0 to 9)
84gain audio gain level n (0 to 31, default is 16)
85bars 0 => testcard bars when incoming video signal is lost
86 1 => testcard bars when incoming video signal is lost (default)
87
88
89SUPPORTED TV STANDARDS AND RESOLUTIONS
90--------------------------------------
91
92The following TV standards are natively supported by the hardware and are
93usable as (for example) the "norm=" parameter in the mplayer command:
94
95 PAL_BGHIN, NTSC_N_443,
96 PAL_Nc, NTSC_N,
97 SECAM, NTSC_M, NTSC_M_JP,
98 PAL_60, NTSC_443,
99 PAL_M.
100
101In addition, the driver offers "custom" pseudo-standards with a framerate
102which is 20% of the usual framerate. These pseudo-standards are named:
103
104 PAL_BGHIN_SLOW, NTSC_N_443_SLOW,
105 PAL_Nc_SLOW, NTSC_N_SLOW,
106 SECAM_SLOW, NTSC_M_SLOW, NTSC_M_JP_SLOW,
107 PAL_60_SLOW, NTSC_443_SLOW,
108 PAL_M_SLOW.
109
110
111The available picture sizes are:
112
113 at 25 frames per second: 720x576, 704x576, 640x480, 360x288, 320x240;
114 at 30 frames per second: 720x480, 640x480, 360x240, 320x240.
115
116
117WHAT'S TESTED AND WHAT'S NOT
118----------------------------
119
120This driver is known to work with mplayer, mencoder, tvtime, zoneminder,
121xawtv, gstreamer and sufficiently recent versions of vlc. An interface
122to ffmpeg is implemented, but serious audio-video synchronization problems
123remain.
124
125The driver is designed to support all the TV standards accepted by the
126hardware, but as yet it has actually been tested on only a few of these.
127
128I have been unable to test and calibrate the S-video input myself because I
129do not possess any equipment with S-video output.
130
131This driver does not understand the V4L1 IOCTL commands.
132
133
134UDEV RULES
135----------
136
137In order that the special files /dev/easycap0 and /dev/easysnd1 are created
138with conveniently relaxed permissions when the EasyCAP is plugged in, a file
139is preferably to be provided in directory /etc/udev/rules.d with content:
140
141ACTION!="add|change", GOTO="easycap_rules_end"
142ATTRS{idVendor}=="05e1", ATTRS{idProduct}=="0408", \
143 MODE="0666", OWNER="root", GROUP="root"
144LABEL="easycap_rules_end"
145
146
147MODPROBE CONFIGURATION
148----------------------
149
150The easycap module is in competition with the module snd-usb-audio for the
151EasyCAP's audio channel, and its installation can be aided by providing a
152file in directory /etc/modprobe.d with content:
153
154options easycap gain=16 bars=1
155install easycap /sbin/rmmod snd-usb-audio; /sbin/modprobe --ignore-install easycap
156
157
158ACKNOWLEGEMENTS AND REFERENCES
159------------------------------
160This driver makes use of information contained in the Syntek Semicon DC-1125
161Driver, presently maintained at http://sourceforge.net/projects/syntekdriver/
162by Nicolas Vivien. Particularly useful has been a patch to the latter driver
163provided by Ivor Hewitt in January 2009. The NTSC implementation is taken
164from the work of Ben Trask.
165