/* This is the README file for libgphoto2/camlibs/digigr8. This README is an * integral part of the libgphoto2/camlibs/digigr8 library source code and is * distributed with that source code under the LGPL license, a copy of which * license may be seen in the head directory of libgphoto2, in the file * COPYING. * Original of this file copyright Theodore Kilgore, 12/05/05. */ INTRODUCTION: The cameras supported here have a controller chip from S&Q Technologies. They have USB Vendor:Product number 0x2770:0x905c. These cameras are cheap and basic. Their functioning resembles that of the cameras supported by the sq905 camera library, but is a bit different. More recently (07/11/2007) I have discovered a camera with Product ID 0x9050 which will also function with the same driver library. A more specific description of this camera can be found in README.9050. Still more recently, several cameras with USB ID 0x2770:0x913D also came onto the market. These cameras also can be made to function with the same code base, in spite of some differences. They are more specifically described in README.913D. The first camera which I knew of with USB ID 0x2770:0x905C was the Digigr8 from RadioShack. Hence comes the name of this camera library. Several more cameras have since been reported, including one which has the same make/model painted on the plastic case as that of a camera which previously used an sq905 chip and used the sq905 Vendor:Product number instead of this one. SQ Technologies seems to have discontinued the SQ905 and the SQ905C is apparently its successor. For information about additional cameras with the same USB ID, I am totally dependent on reports from users and testers. If you have another 0x2770:0x905c camera and want it to work and it currently does not, then I will be very glad to hear from you. Saying this a different way: further progress with your camera will depend upon your input. If on the other hand your camera does work and is not explicitly listed, I would still like to know about it for the sake of completeness. I will give it an explicit line listing in library.c and I will credit you as the finder of the camera, in the ChangeLog file. WHAT CHIP IS ACTUALLY IN THESE CAMERAS? I do not know. I did not take one apart to look inside. (update) Someone has reported to me that he did take his camera apart, and it really is an SQ905C chip inside. WHAT FEATURES DO THESE CAMERAS HAVE, AND WHAT DOES THIS DRIVER SUPPORT? FEATURE LIST SUPPORTED (Y/N/Part) -- USB connection to computer -- High resolution 640x480, uncompressed Y -- Low resolution 320x240, uncompressed Y -- High resolution 640x480, compressed Y -- Low resolution 320x240, compressed Y -- Ability to "switch" resolution between pictures Y -- Ability to download all pictures on camera Y -- Ability to download the first k pictures, where k is less than the number on the camera Y -- Ability to download individual photos Y (faked, but works) -- Shoot a frame and save image to computer Y -- Internal battery, which recharges through the USB port (some models) ------------------------------------------------------------------------- The following things can be done with button-pushes on the camera: ------------------------------------------------------------------------- -- Frequency filter for use in artificial light. Can be set to cancel 60hz or 50hz interference. -- Delete all, delete last, resolution setting, compression mode setting. -- "Clip" mode will shoot three frames. The camera "sees" these frames as ordinary photos. Also the photo counter on the LED counts them. -- "AVI" mode shoots until the shutter button is released, or until the camera is full. The photo counter on the camera does NOT count the AVI frames as separate items, but thinks all of the frames are part of one photo. Otherwise, the camera in fact sees the frames as ordinary photos, so gphoto2 will give the actual count of all frames, no matter whether photos or part of an AVI clip. Accordingly, gphoto2 will download the AVI frames as if they were ordinary photos and will sequentially number the frames in the course of numbering the photos which come out of the camera. The user can easily create a movie from the AVI frames, using an animation program, such as the "animate" command from the ImageMagick package. The default resolution for AVI frames is always 320x240 regardless of the resolution setting chosen for still photos. AVI mode will use compression if it otherwise happens to be turned on. Notes: The 0x2770:0x9050 and 0x2770:913D cameras differ from the above description in some particulars. Please see the respective README files for details. Almost all known cameras supported by the camlibs/digigr8 have a 640x480 high-resolution setting and a 320x240 low-resolution setting. If your 0x2770:0x905c camera uses another resolution setting, then it might still work. There is some similarity with the sq905 cameras, and I kept that part of the code here. Specifically, if the camera has 352x288 and 176x144 resolution settings, these might work but are not tested (Note added July 2007: the code for 352x288 _does_ continue to work; see below). If your camera does not work due to unknown resolution settings, then the new resolution settings need to be listed in digigr8.c in digi_get_picture_width (). Please report any such problem. I will ask you to run a gphoto2 command in debug mode and we can easily find the information we need -- which information, understand, I do not possess unless you share it with me. The pictures obtained on the uncompressed settings can often be superior to those obtained using the software which came with the camera, but not always. Generally, considering that they are cheap, low resolution cameras, these cameras give relatively good pictures. The digigr8 cameras can also function as webcams, but that is outside the scope of gphoto2. HARDWARE LIMITATIONS AND CONSTRAINTS The SQ905C chip, like the SQ905 before it, is a minimalist controller chip; if any of its functionality at all were removed, it would probably be impossible to use it to run a digital camera. To program around the limitations of the chip, therefore, is a special challenge. Here are some examples. 1. The manufacturer's driver will do nothing but to download all photos on the camera, and display them, keeping temporary copies in C:\TEMP, to be deleted when the camera access program is closed. After downloading everything, then, the OEM program allows the user to "select" and to "save" any or all of the photos which have, in fact, already been downloaded (indeed the displayed "thumbnails" came from the files in C:\TEMP, too). Now, gphoto2 does not operate thus, has preconceived notions about how any respectable camera should act, and regards such a primitive camera controller chip as an untamed beast. Thus, many of the gphoto2 functions will not work unless, through a bit of fakery which involves downloading data and throwing it away and on some occasions resetting the camera, this primitive behavior is somewhat improved. That all has to be done in the driver, with fakery invisible to the user. These remarks apply not only to getting thumbnails, but also to many other gphoto2 options as well. See item 2. 2. The camera's data storage provides only sequential access, not random access. In other words, it acts as though it were a tape drive instead of a disk. Worse, it's like a tape drive with no fast forward and no rewind controls. The constraints which this places are obvious. It means for example that to download all the photos on the camera to display thumbnails requires the camera to be reset afterwards, because that is the only way to do the "rewind" required before any of the photos can be accessed again. It also menas that "gphoto2 -p 2" would NOT download the second photo on the camera, unless the support for it is so written as to download the first photo, then the second photo, and to process only the second one, having consigned the data from the first photo to /dev/null. The camera simply cannot do better. The gphoto2 -p 2 command option does work, of course, but only because the necessary jury-rigging has been built into the download function. 3. Considering the way the communication protocols of these cameras seem to work, it would seem nearly impossible to copy any data to the camera for storage and transport. The camera clearly does not have files on it, only data addresses. And the camera does not keep time. For similar reasons, it would also seem impossible to delete a photo from the camera by action of software on the computer. The camera itself supports two choices for deletion: delete the last photo taken, or delete all. Each action is performed by an appropriate sequence of button pushes on the camera. WHAT GUI FRONTENDS DOES THIS CAMERA LIBRARY SUPPORT? Gtkam seems to work well for me with this library, and also flphoto. Some of the other various frontends do not seem to work quite so well for me. But one of them may work nicely for you, and you are hereby encouraged to try whichever one is your favorite. If you want to use either gtkam or digikam, you are encouraged to read the camera's manual (in gtkam, right-click on the name of the camera in the left panel, after starting the program and having chosen the correct camera). NOTES 1. The program is set up to put out pictures in PPM or raw format. The OEM program offers JPEGs. If the user desires JPEG output, then that can easily be done on Linux, using other software which exists independently from libgphoto2. 2. As of 01/20/2008, all raw files downloaded from these cameras will have a "footer" of length 16 bytes. This footer consists of the line from the camera's allocation table, which gives some information about the photo. The information includes a code for the resolution and compression setting and some information which may be useful in the future relating to color and lighting. Unfortunately, the meaning of the color and lighting information is not well enough understood to be useful at this time, but it may be useful in the future, so why not preserve the information? 3. The gamma setting (actually seems to be one over gamma) used for the construction of PPM image files has been obtained by trial and error. It seems to work very well for outdoor pictures, but the setting is a compromise between what happens with outdoor photos and what happens with indoor photos. Conceivably, the program could support a choice between two or more gamma settings, optimizing for different conditions. 4. A still-experimental postprocessing routine is added, to provide some sharpening and color correction for different lighting conditions. The routine can easily be turned off if one wishes, and because it is experimental you may so wish. To disable it, just comment out the line in get_file_func ( ) in library.c where the function digi_postprocess ( ) is called. Then do "make install" to install your change. 5. An experimental program for processing raw files into finished photos is available now, in gphoto2/trunk/playground/raw_converters/sq_raw_converter Please try this program. If the results are good, I will incorporate the routines used there directly into libgphot02/camlibs/digigr8. I like the results, but they need testing. 6. The "High Compression" setting uses an unpublished compression algorithm. However, after serious effort the decompression seems to work pretty well. There are at this time (01/20/2008) no known issues with it. 7. Please get back to me with reports about other SQ cameras (any cameras with Vendor number 0x2770), with their specifications (what it says in the OEM manual about resolution and number of pictures, as well as make and model, and whether it works or not with any libgphoto2 driver or not, would be enough), and with a log file if it seems it is supposed to work but there are problems. A NOTE ON CAPTURE AND ON CHANGING THE RESOLUTION SETTING FOR CAPTURE These cameras will perform "gphoto2 --capture-preview" which means, to shoot a frame and download it to the computer immediately. On the 0x9050 camera, the same USB command which trips the shutter will simultaneously delete all frames on the camera. On the 0x905C cameras, capture works, but will not affect whatever is on the camera. The default resolution setting for capture with all these cameras is 320x240. For those cameras which will do 640x480 resolution in still photo mode, there is a tweak which can cause the camera to do the capture at 640x480 as well. It is as follows: Look through the code in camlibs/library.c for the capture function. You will see a USB command in which the digit 0x1440 appears. Change that to 0x2840 and re-compile and re-install. It is also possible to get 160x120 resolution, but that is not so interesting. Evidently, the "40" means to do capture, and the previous two digits are the resolution setting in hexadecimal, with the final "0" removed. For example, 640=0x280 -> 0x2840 and 320=0x140 -> 0x1440 (which, again, is the default setting). I am not sure what would happen if the resolution setting here is too high for the camera (the known 0x9050 camera will only do 352x288 at max resolution in still mode, for instance). Therefore, this tweak is not implemented. However, it does work for me with those cameras for which it works. It should be repeated, too, that this tweak is not documented by any manufacturer and is not available in the OEM driver for any of these cameras. WARRANTY? Absolutely not. No warranty. Never. Not responsible for any actual or potential damage or consequences to anyone or to the equipment of anyone for using this program, whether the alleged damage or alleged consequences are claimed to be real, imaginary, direct, collateral, for pain and suffering, or are claimed to be inflicted upon any "third party" who is not the user or installer of the program. The program has been written for my pleasure and to broaden and deepen my knowledge of computer hardware and software. The program has not been written with the immediate expectation of financial gain or profit on my part, nor has it been commissioned for pay. It is presumed that any end-user of this program will have access to the source code of the program and can judge for himself or herself whether he/she wishes to use it or not, or can consult someone with appropriate expertise to make such a judgment. Theodore Kilgore 12/05/05 (revised 12/29/05, 03/28/07, 06/25/07, 07/16/07, 07/23/07, 01/21/08, 01/22/08)