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AN526
Application Notes
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Analog Devices AN526 Application Notes

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a
One Technology Way • P.O. Box 9106 • Norwood, MA 02062-9106 • 781/329-4700 • World Wide Web Site: http://www.analog.com
APPLICATION NOTE
ADV601 Video Codec Frequently Asked Questions
by David Starr
IS THE ADV601 AVAILABLE?
Yes: It is in stock in the warehouse and at our distributors. Not all the distributor people know this yet, but we did ship a good deal of product to them. Prices are per 10,000-piece lots.
WHAT TECHNICAL INFORMATION IS AVAILABLE ON THE WORLD WIDE WEB?
Point your web browser to www.analog.com, the main Analog Devices page. Drop “ADV601” into the search engine to travel to the special ADV601 page. Here you can download the data sheet.
The Data Sheet
The ADV601 data sheet is available from the Norwood Literature Center in the United States (800-262-5643, press 2); in the UK (01932 266 000). It is also available on the ADV601 web page in Adobe Acrobat form.
The FTP Site
Find a hot-link (pointer) to the ftp site where the following ADV601 data is posted.
Application Notes
Ontheair.doc
Hints and kinks learned (while getting the Videolab board to run).
Dspbinwd.doc
Control ADV601 bit rate with an ADSP-21xx family DSP.
Binwidth.zip
Schematics and Pal Code for the Videolab Evaluation Board
A 32-bit wide PCI bus design.
Software Simulator
A software-only demo in file icm.zip.
Download it, unzip it on a Windows the setup.exe. This will give you a nice software com­pression and decompression program that works on still images. It lets you compress as much as you like and shows a side by side, before and after to evaluate quality of the compressed image. Source code for the demo pro­gram is included. It is based on a Video-for-Windows software Codec compatible with standard Windows video programs such as Mediaplayer and Adobe Pre­miere. Use Wavelet image compression with your favor­ite Video-for-Windows tool.
Hardware diagnostic program 601test.
MS-DOS application ideal for debugging new hardware. Easily adapted to new hardware designs.
Windows 95 Drivers 601rpman and 601cman.
[We have] a Windows 95 Plug and Play interrupt service routine (601rpman.vxd) and a bit rate control program (601cman.dll). This is a matched set of low level drivers. Source code is posted.
Raw2avi file converter.
A Windows 95 tool that converts raw ADV601 video to the “audio-visual-interaction” .avi video acceptable to standard video-for-windows programs. Capture video with the Videolab board and edit with your favorite Win­dows application.
IS THERE AN EVALUATION BOARD?
HOW DOES THE VIDEO LOOK AFTER COMPRESSION?
At 10:1 it looks as good as you get at home on good pro­gram material (say a ball game on a bright sunny after­noon). At 30:1 it looks as good as a VHS rental tape. At 200:1 you can still read the numbers on a football player’s shirt. Download the software simulator from the ftp site and see for yourself.
®
95 machine and run
Windows is a registered trademark of Microsoft Corporation.
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WHAT HAPPENS WHEN I PUT THE VIDEOLAB CD-ROM INTO MY PC?
We care about this because it is easy to do the high level install and fail to do the low level install. Low level install (file complete.inf) is supposed to ask if you want to reboot, and you must say “YES” for the install to “take.” Low level install causes the high level install (file setup.exe) to start right after the reboot. If by chance win­dows fails to offer a reboot, do it by hand. You have a better chance to kick off the low level install automati­cally, (Method 1) if you INSTALL THE HARDWARE FIRST. If this fails (incautious mouse clicking can cause Win­dows 95 to skip the low level install, or fail to find the CD­ROM drive) then, Method 2 ,“Add New Hardware,” gives you a second chance.
Low level install is started one of three ways:
Windows 95 Detects the Hardware
You will see the “Windows has detected new hardware” message. Once Windows 95 sees the hardware, it re­members the card forever, and won’t ask again. You have one only shot at #1, which explains why they have #2 and #3. In all three cases, ALWAYS hit the “have disk” tab. Otherwise, Windows 95 will try to find exist­ing drivers on your hard drive. It sometimes finds old drivers, or drivers for some other product. You don’t want that. Watch the activity LED on the CD-ROM drive. It ought to flash when Windows loads drivers from it. Never let Windows bypass the driver software installation because it will be very difficult to install the drivers later. Windows must offer a choice be­tween “Complete.inf” and “sim_only.inf”. Always select “complete.inf”.
Click On “Add New Hardware” in the Control Panel Click On “Change Driver” in “Device Manager”
Clicking on the Start button will put you into device man­ager, then “Settings,” then “System” (icon of computer with a blue screen) and then the Device Manager tab. Look for “Video Capture and Compression” device. If present, you can do “Change Driver.” If not present, it means you never reached low level install. Try the “Add New Hardware” applet on the “Control Panel” instead.
How Do You Tell Which Install[s] Have Been Done?
The low level install is quick and almost invisible. It puts “ADV601 Video Lab Card” into device manager upon completion. If this is missing, a low level install is re-
quired. A yellow exclamation point (!) on the ADV601 Video Lab Card entry means the low level install ran, but there is a resource conflict. (See below.)
The high level install puts up a flashy blue screen with “ADV601 Videolab 97” in large white 20-point type, with shadows showing under the letters. It also puts the “Videolab” icon on the Start button’s program menu and a shortcut “To the Videolab” on your desktop.
WHAT DO YELLOW EXCLAMATION POINTS IN DEVICE MANAGER MEAN?
Configuration Manager in Windows 95 tries to dole out limited hardware resources to a herd of picky plug and play cards. The four resources are:
1. Memory Addresses
2. IO Port Addresses
3. DMA Channels
4. Interrupt Request Lines (IRQs) Video lab needs only some memory and ONE (1) IRQ. The
average PC has lots of memory, but only 15 interrupt (IRQ) lines, so it’s the IRQ’s that run out. In Windows 95­speak this is called a “resource conflict.” Device Manager will show a yellow exclamation point on the offending device[s] and the Properties Sheet will say “This device is causing a resource conflict,” or “This device is not work­ing,” or other similar comments.
IRQ resource conflicts are fixed either by removing one of the conflictor’s (IRQ hogs) from the machine or moving one of them to a spare IRQ. If you click on the “Computer” icon at the top of the Device manager tree you can see all the IRQ’s. If 0 through 15 (all of them) are in use, some­thing will have to be removed, you are flat out of IRQ’s and there is no way to make any more. On my machine for example, I removed my parallel port (LPT1) to free up IRQ 7 and the 2nd IDE disk controller to free up IRQ 15.
The LPT port and the IDE disk controller are usually inte­grated into the motherboard and you “remove” them in software. If they are real plug-in cards, you can really re­move them by pulling them out of the machine. In the software “removal” case, you have to get into the “CMOS Setup Routine,” which is part of BIOS. On late model Gateway’s, hold down the F1 key at power-up time. Other machines work about the same, but you hold down a different key. The “CMOS Setup Routine” is menu driven and you should be able to disable the un­needed peripherals.
Once you have some wiggle room (a free IRQ or two) start up Windows 95. Get into device manager (Click
Start
, Click Click on Device Manager Tab). Check the devices you just removed. If they still show in the Device Manager win­dow, Device Manager was too smart for its own good. It “saw” the disabled device at boot time and loaded the driver for it, consuming the resource you were trying to
Settings
, Click
Control Panel
, Click
System
,
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free up. Let Device Manager know who is in charge. “Remove” the device. He will whine about it, “Warning: You are about to remove this device from your system,” but be firm with him and click OK.
Now, from the start button click on “Help.” In the help menu click on the “Contents” tab, then Open the Troubleshooting book. Click on “If you have a hardware conflict.” This starts the “Wizard,” which gives you step­by-step coaching to move conflicting IRQs around until they no longer clash. IRQ assignments are changed on the “Resource” tab of the device properties sheet. You often have to change the “Setting Based On” box from “Basic Configuration 0001” to something else like, “Ba­sic Configuration 0002,” before Device Manager will let you make any changes.
Device Manager should offer to reboot when you are done. Take him up on this and reboot. If Device Manager forgets to ask you to reboot, do it anyhow to make the changes stick. Upon reboot, device manager may “dis­cover” the hardware you just “removed” and will load the drivers you just removed. This doesn’t hurt because the devices you care about (Videolab) have a priority on resources and newly discovered devices lose out. On some machines the unused parallel port shows up with a resource conflict exclamation point. (Last card into the machine is a loser). My sound card, fax modem and Video lab card show “OK” and work properly.
CAN I JUST COPY THE .EXE FILES TO C: AND RUN THE VIDEOLAB CARD?
No. Under Windows 95, no ordinary program (.exe file) is allowed to perform I/O instructions or change the memory management hardware of the CPU. The Videolab card is memory mapped and requires memory management changes before a program can “see” the card in address space.
In all cases, you want Windows 95 to get the driver and the install script from CD-ROM. Always choose the “Have Disk” option. Be careful that Windows 95 is loading new drivers from your floppy disk and not reloading the old drivers from hard disk. Windows 95 saves the install script (and perhaps the old drivers) in hidden locations on the hard drive.
After a driver install (using complete.inf), you must reboot Windows 95 before the new vxd becomes effec­tive. The old vxd has been loaded into memory at boot time and remains in control until you reboot. Windows 95 SOMETIMES prompts you to reboot, and SOMETIMES fails to prompt you. ALWAYS REBOOT.
The complete.inf script ONLY loads the vxd onto your system. The application programs (601Test, SOFTVCR and the rest) are loaded by running setup.exe on the in­stall diskette. The CD-ROM will automatically run setup.exe when you stick it in the drive if the “auto insert notification” feature of Windows 95 is active. Alterna­tively, you can start setup.exe from the “ADD/Remove Programs” applet in “Control Panel,” or you can click on setup.exe in Explorer or you can Run D:setup.exe from the start button.
Bottom line. To run VideoLab on a new PC,
1. Get the latest Videolab Software Diskette. We im­prove the software day by day, so it pays to get the very best.
2. Power down the CPU, and insert the VideoLab card and power up.
3. Windows will report “New hardware detected” and ask for a diskette.
4. After the complete.inf script ends, run the setup.exe program from the delivery CD-ROM to install the ap­plication programs. After both the vxd and the ap­plication program installs are done, then reboot.
Only specially constructed (privileged) programs (“vxd’s” in Windows 95-speak) are allowed to do the heavy lifting necessary to operate the Videolab card. Videolab comes with such a vxd (601rpman.vxd), and it must be installed in a special way or it won’t work. The “vxd” and Windows 95 have to be formally introduced to each other. The script for this introduction is a file on the install diskette named Complete.inf. The script says
1. Delete the old version of the vxd and the DLL’s.
2. Make some entries in the Registry connecting hard­ware device 0601 to driver 601rpman.vxd.
3. Copy the new version onto hard disk from floppy disc.
WHAT IS THE SOFTWARE SIMULATOR?
We have a software simulator customers can use to evaluate quality of the compressed image. It runs on Windows 95 machines and can be downloaded from the FTP site (file icm.zip).
Copy icm.zip onto your Windows 95 machine, decom­press it with pkunzip and then execute the setup.exe pro­gram that comes out of the zip file. This will install the software ADV601 Codec and a test program that gives you a side by side comparison of any image before or after compression. It can handle windows .bmp files of the right size. You must have Windows 95 on your machine.
The simulator package consists of a Video-for-Windows compliant software Codec (adv601.dll) and a simple ap­plication program (icmapp.exe). You have to run the setup file to install the software Codec. Once you do this
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