Hi Markus, On Tue, 2003-01-28 at 10:42, Markus Nilsson wrote: > You pointed me to the API description, the only documentation I've found however is > /usr/linux/Documentation/video4linux/API.html > which doesn't help me much :( Yes, the MJPEG extensions are described in the 'Zoran' file in Documentation/video4linux/. I've attached it for reference (README). The comments I gave in my other email should help you on the right way, in combination with the MJPEG extensions description. If it doesn't help good enough, please tell me and I'll give some further help if I can. Ronald -- Ronald Bultje <rbultje@xxxxxxxxxxxxxxxxxxx> Linux Video/Multimedia developer
DC10/DC10plus/LML33/Buz Driver for Linux ========================================= by Rainer Johanni <Rainer@xxxxxxxxxx> (for Iomega Buz Driver) Adapted for DC10/DC10plus by Wolfgang Scherr <scherr@xxxxxxxxxxx> Further changes for DC10/DC10plus and LML33 cards by Serguei Miridonov <mirsev@xxxxxxxxx> Current homepage: http://www.cicese.mx/~mirsev/Linux/DC10plus/ Current maintainer: Serguei Miridonov <mirsev@xxxxxxxxx> This is a driver for DC10plus capture cards from Pinnacle Systems Inc., LML33 cards from Linux Media Labs and Buz from Iomega. It also works with many old Miro DC10 cards with SAA7110A TV decoder and ADV7176 TV encoder (please, make sure that your card has these chips, otherwise the driver will not work). The driver is Video4Linux compliant and contains extensions to provide hardware support for full motion MJPEG compression and decompression. Since this driver is a derivative from the driver for Buz Iomega cards written by Dr. Rainer Johanni, http://www.johanni.de/munich-vision/buz/ they both have compatible API. I hope that this API will become a part of V4L standard. Copyright: This driver is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License. Please, check http://www.gnu.org/ for details. No warranty: This software is provided on AN "AS-IS" basis WITHOUT WARRANTY OF ANY KIND. YOU USE IT AT YOUR OWN RISK. CONTENTS ~~~~~~~~ Supported Formats Hardware compression Compiling and Loading the Driver Driver Options Tested applications Programming interface Features for testing Mailing lists Bug Reports Supported Formats ================= Card: DC10/DC10plus LML33/Buz TV standard: NTSC/PAL/SECAM(*) NTSC/PAL Format: Square pixel CCIR.601 640x480 NTSC 720x480 NTSC 768x576 PAL/SECAM(*) 720x576 PAL Frame rates: 30 frames/60 fields per second NTSC 25 frames/50 fields per second PAL/SECAM(*) (*) - SECAM is supported for input only in DC10/DC10plus cards. The output of the recorded SECAM video stream will be in PAL standard. Also, please, note that monitoring of the SECAM input signal at the DC10/DC10plus analog output may not be available. Please, use appropriate application like XawTV to watch full color SECAM video at the card input. Hardware compression ==================== Since the card provides hardware compression, even low end machines can be successfully used for movie capture and playback. I'm testing the driver with with 2.2.16 kernel running on 233 MHz Pentium MMX with 64M RAM on 430TX motherboard and with 10GB IDE drive from Western Digital Corp. On one test run with DC10plus card I've got 0 frames dropped during about 20 minutes of full motion NTSC (I live in Mexico) video capture with fully synchronized audio. The command was lavrec -fa -in -d1 -l -1 -q30 -w /dos/g/capture/Linux/test%03d.avi for recording, and lavplay -n128 /dos/g/capture/Linux/test*.avi for playback. (See lavtools distribution for more information). Typical run of similar test can provide as few as 6-8 dropped frames per half of an hour. You mileage may vary, though. Compiling and Loading the Driver ================================ You should run a 2.2.x kernel in order to use this driver. The driver was also tested with 2.4-test6 kernel, so hopefully it will work with 2.4 kernels too. I would recommend to use only official kernels from www.kernel.org and its mirrors. Kernels supplied with some Linux distributions may be patched in some way to meet specific needs of particular Linux distributor and could be incompatible with this driver. As a driver maintainer, I am not able to follow every unofficial kernel release, and no unofficial kernels will be supported. Besides the files in this directory, the driver needs the 'videodev' and the 'i2c' module from the Linux kernel (i2c-old for 2.4 kernels). In order to get these modules available, enable module support for VIDEODEV and BTTV (which implies i2c) in your 2.2.x kernel configuration. You will find these devices in the menu "Character Devices" in your Kernel Configuration. In newer kernels (2.4) instead of BTTV you should enable support for Iomega Buz cards and for Zoran 36060/36067 chipset. This will include i2c or i2c-old modules and Buz/LML33 driver. However, instead of modules for Buz/LML33 driver from the kernel, use modules from _this_ driver. To compile the driver, just type make. Before you load the driver you must have a video device at major device node 81. If you don't have it yet, do the following (as root!): cd /dev mknod video0 c 81 0 ln -s video0 video If you have more than one card, add more nodes in /dev directory: mknod video1 c 81 1 mknod video2 c 81 2 ... The driver should operate properly with several cards. It was tested with one DC10plus and one LML33 cards installed together and the driver correctly identifies both cards and works with both of them. Currently the driver does not support LML33 and Buz cards installed together in the same system. This will be fixed in future versions. Edit the 'update' script if you want to give the driver special options (see below for options descriptions) and then type (as root) ./update <card_list> to insert all necessary modules into the kernel. <card_list> is a list of cards installed in your system separated by white space. Supported cards are dc10, dc10plus, lml33, and buz. For example, if you have both dc10plus and lml33 cards, please type ./update dc10 lml33 If you want to make full use of the Video for Linux _uncompressed_ grabbing facilities, you must either - obtain and install the "big_physarea patch" for your kernel and set aside the necessary memory during boot time. There seem to be several versions of this patch against various kernel versions floating around in the net, you may obtain one e.g. from: http://www.polyware.nl/~middelin/patch/bigphysarea-2.2.1.tar.gz You also have to compile your driver AFTER installing that patch in order to get it working or - start your kernel with the mem=xxx option, where xxx is your real memory minus the memory needed for the buffers. For doing this add an entry in lilo.conf (if you use lilo): append "mem=xxxM" or add a line in your linux.par file (if you use loadlin): mem=xxxM The second method is by far easier, however it is dangerous if more than one driver at a time has the idea to use the memory leftover by setting the mem=xxx parameter below the actual memory size. Read also below how to use this memory! If you use only MJPEG compressed capture provided by the driver, you should not need large memory areas for DMA. In this case, you will be able to capture and playback movies with lavtools, however you will not be able to use capture features of XawTV and other similar programs (you can still watch video on the screen). Driver Options ============== You are able to customize the behavior of the driver by giving it some options at start time. default_input, default_norm --------------------------- As soon as the driver is loaded, the Buz samples video signals from one of its input ports and displays it on its output. The driver uses the Composite Input and the video norm PAL for this. If you want to change this default behavior, set default_input=1 (for S-VHS input) or default_norm=1 for NTSC or default_norm=2 for SECAM (DC10/DC10plus only). lock_norm --------- This option was introduced to disable norm (TV standard) change by some not well behaving programs. For example, if you have some application which was written by somebody who lives in a country with PAL standard, this program may not have NTSC option and may always try to set the driver to PAL. In this case, you may load the driver with default_norm=1 and lock_norm=1 and the card will be forced to work in NTSC standard only. Options: lock_norm=0 default, TV standard change is enabled; lock_norm=1 TV standard change is disabled but the driver will not notify the application about any error; lock_norm=2 TV standard change is disabled and the driver will notify the program that TV standards other than set by default_norm=X option are not supported. pass_through ------------ When the driver is not in use (device is not opened by any program) and pass_through=0 (default) the driver will set the TV encoder to produce color bar signal at the output. If the driver was loaded with pass_through=1, the color bar will be disabled and input signal will be sent to the output even if the driver not in use. If you have LML33 card and wish the color bar signal at the output, you will also need to set lml33dpath=1 (please, see next section). lml33dpath ---------- LML33 card normally (lml33dpath=0) connects its output to the input using analog switch. Additionally, it also allows real-time monitoring of digitized video using TV monitor connected to the output. This "digital path" option can be enabled setting lml33dpath=1. In this mode, the input is connected only to the TV decoder, digital video data is sent via internal video bus to the TV encoder and resulting analog signal is sent to the output. This mode could be very useful for testing and picture adjustment while watching video at the TV monitor connected to the output. However, because of lack of 75 ohm terminating resistors at TV decoder input, the signal will suffer serious distortions. # These distortions could be eliminated by soldering two 75 ohm resistors # in LML33 card: in parallel to capacitors C73 and C82 (see schematics of # H33 board available at www.linuxmedialabs.com and www.zoran.com). Be # aware, however, that doing so will void card warranty and the card, # after this change, must always be used with loading option lml33dpath=1. # # WARNING: I DID NOT TRY THIS CARD CHANGE YET, THIS IS JUST AN ASSUMPTION # AND I WILL NOT BE RESPONSIBLE FOR ANY DAMAGE ASSOCIATED WITH THIS # CHANGE. IF YOU WISH TO TRY IT, DO IT AT YOUR OWN RISK. Please, note that DC10/DC10plus cards always use "digital path" for signal monitoring. Its input and output are both properly terminated and the digitized signal quality does not depend on the connection of the output load. v4l_nbufs, v4l_bufsize ---------------------- In order to make to make full use of the Video for Linux uncompressed picture grabbing facilities of the driver (which are needed by many Video for Linux applications), the driver needs a set of physically contiguous buffers for grabbing. These parameters determine how many buffers of which size the driver will allocate at open (the open will fail if it is unable to do so!). These values do not affect the MJPEG grabbing facilities of the driver, they are needed for uncompressed image grabbing only!!! v4l_nbufs is the number of buffers to allocate, a value of 2 (the default) should be sufficient in almost all cases. Only special applications (streaming captures) will need more buffers and then mostly the MJPEG capturing features of the Buz will be more appropriate. So leave this parameter at it's default unless you know what you do. The things for v4l_bufsize are more complicated: v4l_bufsize is set by default to 128 [KB] which is the maximum amount of physically contiguous memory Linux is able to allocate without kernel changes. This is sufficient for grabbing 24 bit color images up to sizes of approx. 240x180 pixels (240*180*3 = 129600, 128 KB = 131072). In order to be able to capture bigger images you have either to - obtain and install the "big_physarea patch" and set aside the necessary memory during boot time or - start your kernel with the mem=xxx option, where xxx is your real memory minus the memory needed for the buffers. In that case, useful settings for v4l_bufsize are - 1296 [Kb] for grabbing 24 bit images of max size 768*576 - 1728 [Kb] for 32bit images of same size (4*768*576 = 1728 Kb!) You may reduce these numbers accordingly if you know you are only grabbing 720 pixels wide images or NTSC images (max height 480). In some cases it may happen that Linux isn't even able to obtain the default 128 KB buffers. If you don't need uncompressed image grabbing at all, set v4l_bufsize to an arbitrary small value (e.g. 4) in order to be able to open the video device. triton, natoma -------------- The driver tries to detect if you have a triton or natoma chipset in order to take special measures for these chipsets. If this detection fails but you are sure you have such a chipset, set the corresponding variable to 1. This is a very special option and may go away in the future. Tested applications =================== XawTV to watch video on your computer monitor. kwintv the same (you might need to use option lock_norm=1). lavtools To record and playback AVI or Quicktime files. Note: you will need patched version, lavtools-1.2p2 to support new features of this driver. Please visit driver homepage for more info. Broadcast2000 reportedly (I didn't try that) can accept movies recorded by lavrec in Quicktime format for editing and then edited movie can be played back by lavplay program. MainActor 3.5x also can accept movies recorded by lavrec for editing. The driver can to be used by two programs at the same time (please, see warning note below regarding this feature). Using XawTV you can watch what you are recording or playing back with lavtools. I've tested the following sequence and it worked for me: * start xawtv and switch inputs, TV standards, and adjust video (contrast, saturation, etc.). You may also run your favorite audio mixer application to adjust audio inputs. * run lavrec with options: -i<set your input and norm here> (to choose proper input and TV standard) -l -1 (to use audio mixer settings) Other lavrec option can be added at your choice. * watch the movie in xawtv window while recording it as AVI or Quicktime file. * when recording is finished, run lavplay or xlav and watch your clip in xawtv window. * Note: you should not quit xawtv during recording or playing back. If you quit xawtv during recording or playback, another lavtools program will stop and may even crash. I'm not sure that the same will work for you. You can try but, please, be careful. WARNING! This is an experimental feature and I'm not sure if it will be supported in the future. The original driver was not designed to be used like this and it has no protection against any interference between two running programs. THEREFORE, IT IS POTENTIALLY DANGEROUS AND SINCE THE DRIVER OPERATES IN KERNEL SPACE, USING THIS FEATURE MAY CRASH YOUR ENTIRE SYSTEM. Programming interface ===================== This driver should be fully compliant to Video for Linux, so all tools working with Video for Linux should work with (hopefully) no problems. A description of the Video for Linux programming interface can be found at: http://roadrunner.swansea.linux.org.uk/v4lapi.shtml Besides the Video for Linux interface, the driver has a "proprietary" interface for accessing the Buz's MJPEG capture and playback facilities. For a full description of all members and ioctls see "zoran.h" (used to be buz.h or dc10.h in previous versions, so, please, update your programs accordingly). The ioctls for that interface are as follows: BUZIOC_G_PARAMS BUZIOC_S_PARAMS Get and set the parameters of the buz. The user should always do a BUZIOC_G_PARAMS (with a struct buz_params) to obtain the default settings, change what he likes and then make a BUZIOC_S_PARAMS call. BUZIOC_REQBUFS Before being able to capture/playback, the user has to request the buffers he is wanting to use. Fill the structure zoran_requestbuffers with the size (recommended: 256*1024) and the number (recommended 32 up to 256). There are no such restrictions as for the Video for Linux buffers, you should LEAVE SUFFICIENT MEMORY for your system however, else strange things will happen .... On return, the zoran_requestbuffers structure contains number and size of the actually allocated buffers. You should use these numbers for doing a mmap of the buffers into the user space. The BUZIOC_REQBUFS ioctl also makes it happen, that the next mmap maps the MJPEG buffer instead of the V4L buffers. BUZIOC_QBUF_CAPT BUZIOC_QBUF_PLAY Queue a buffer for capture or playback. The first call also starts streaming capture. When streaming capture is going on, you may only queue further buffers or issue syncs until streaming capture is switched off again with a argument of -1 to a BUZIOC_QBUF_CAPT/BUZIOC_QBUF_PLAY ioctl. BUZIOC_SYNC Issue this ioctl when all buffers are queued. This ioctl will block until the first buffer becomes free for saving its data to disk (after BUZIOC_QBUF_CAPT) or for reuse (after BUZIOC_QBUF_PLAY). BUZIOC_G_STATUS Get the status of the input lines (video source connected/norm). This ioctl may be subject to change. For programming example, please, look at lavrec.c and lavplay.c code in lavtools-1.2p2 package (URL: http://www.cicese.mx/~mirsev/DC10plus/) and the 'examples' directory in the original Buz driver distribution. Additional notes for software developers: The driver returns maxwidth and maxheight parameters according to the current TV standard (norm). Therefore, the software which communicates with the driver and "asks" for these parameters should first set the correct norm. Well, it seems logically correct: TV standard is "more constant" for current country than geometry settings of a variety of TV capture cards which may work in ITU or square pixel format. Remember that users now can lock the norm to avoid any ambiguity. Features for testing ==================== When loaded, the driver creates a /proc/zoranX entry for each card: using 'cat /proc/zoran0' for your first card you can see the contents of ZR36057/67 chip registers. It is also possible to modify the contents of some registers directly. WARNING: modified contents is not stored in the driver memory, if you restart any program which uses this driver or even change position or cause redraw of a window of xawtv or other program, the original registers contents will be restored by the driver. However, it can be used to change ZR36067 registers on the fly for fine tuning and then to include these changes into driver code. This feature is very limited and still requires some documentation. However, if you are impatient, look at zoran_procfs.c code and (IMPORTANT!) read ZR36057/67 manual. To set TopField bit, for example, you need to type as root: echo TopField=1 > /proc/zoranX # change X to 0 for your first card, # 1 for second and so on... If you use this feature and have found some interesting result, please, let me know. Mailing lists ============= There are two mailing lists available to discuss application issues and suggest driver improvements: 1. A mailing list buz-linux was set up to discuss Iomega Buz driver. Since this driver is derivative of that driver, you can also post your questions and suggestions there. Subscribe with a message (with "subscribe" in the subject) to buz-linux-subscribe@xxxxxxxxxxxxx Unsubscribe with a message (with "unsubscribe" in the subject) to buz-linux-unsubscribe@xxxxxxxxxxxxx The mailing list archive can be found at http://buz.webmages.com/list/. 2. Video4Linux mailing list is set for more general discussions related to uncompressed video capture, V4L and V4L2 API, many Video4Linux applications, etc. to subscribe to this mailing list, please, visit https://listman.redhat.com/mailman/listinfo/video4linux-list Bug Reports =========== If you have found a bug, please, do the following: 1. Edit first line of zoran.c file and set DEBUGLEVEL to 3; 2. Recompile the driver and install it running update script in the driver directory; 3. Run the application(s) which you used when you had found a suspisious behavior; 4. When application stops, look at you /var/log/messages file (or whatever file you use to log kernel messages) and copy all lines related to the driver activity to a separate file in the same order of their appearence in your log file. 5. Mail a message to <mirsev@xxxxxxxxx> with a subject "Linux DC10(plus)/LML33/Buz driver bug report" with a detailed description of your problem, kernel version, application name and attach that file with kernel messages as plain text (please, don't attach it using base64, uuencode, or any other encoding). If you have a Buz card, please, also mail the same message to Wolfgang Scherr <scherr@xxxxxxxxxxx>
