Mac

I have noticed a trend lately of computers making an annoying whining sound when they are running at low utilization. This happens with my Dual G5 PowerMac, the Dells I ordered 18 months ago for my staff (before we ditched Dell for HP due to the former’s refusal to sell desktops powered with AMD64 chips instead of the inferior Intel parts), and I am starting to notice it with my MacBook Pro when in a really quiet room.

These machines emit an incredibly annoying high-pitched whine when idling, one that disappears when you increase the CPU load (I usually run openssl speed on the Macs). Probably the fan falls in some oscillating pattern because no hysteresis was put into the speed control firmware. It looks like these machines were tested under full load, but not under light load, which just happens to be the most common situation for computers. The short-term work-around is to generate artificial load by running openssl in an infinite loop, or to use a distributed computing program like Folding@Home.

Load-testing is a good thing, but idle-testing is a good idea as well…

A colleague was asking for some simple advice about all-in-one printer/copier/fax devices and got instead a rambling lecture on my paper workflow. There is no reason the Internet should be exempted from my long-winded rants, so here goes, an excruciatingly detailed description of my paper workflow. It shares the same general outline as my digital photography workflow, with a few twists.

Formats

The paperless office is what I am striving for. Digital files are easier to protect than paper from fire or theft, and you can carry them with you everywhere on a Flash memory stick. As for file formats, you don’t want to be locked in, so you should either use TIFF or PDF, both of which have open-source readers and are unlikely to disappear anytime soon, unlike Microsoft’s proprietary lock-in format of the day.

TIFF is easier to retouch in an image editing program, but:

1. Few programs cope correctly with multi-page TIFFs
2. PDF allows you to combine a bitmap layer to have an exact fac-simile with a searchable OCR text layer for retrieval, TIFF does not.
3. TIFF is inefficient for vector documents, e.g. receipts printed from a web page.
4. The TIFF format lacks many of the amenities designed in a format like PDF expressly designed as a digital replacement for paper.

Generating PDFs from web pages or office documents is as simple as printing (Mac OS X offers this feature out of the box, for Windows, you can print to PostScript and use Ghostscript to convert the PS to PDF.

Please note the bloated Acrobat Reader is not a must-have to view PDFs, Mac OS X’s Preview does a much better job, and on Windows Foxit Reader is a perfectly serviceable alternative that easily fits on a Flash USB stick. UNIX users have Ghostscript and the numerous UI wrappers that make paging and zooming easy..

Acquisition

You should process incoming mail as soon as you receive it, and not let it build up. If you have a backlog, set it aside and start your new system, applicable to all new snail mail. That way the situation does not degrade further, and you can revisit old mail later.

Junk mail that could lead to identity theft (e.g. credit card solicitations) should be shredded or even better, burnt (assuming your local environmental regulations permit this). if you get a powerful enough shredder, it can swallow the entire envelope without even forcing you to open it. Of course, you should only consider a cross-cut shredder. Junk mail that does not contain identifiable information should be recycled. When in doubt, shred. Everything else should be scanned.

Forget about flatbed scanners, what you want is a sheet-fed batch document scanner. It should support duplex mode, i.e. be capable of scanning both sides of a sheet of paper in a single pass. For Mac users Fujitsu ScanSnap is pretty much the only game in town, and for Windows users I recommend the Canon DR-2050C (the ScanSnap is available in a Windows version, but the Canon has a more reliable paper feed less prone to double-feeding). Either will quickly scan a sheaf of paperwork to a PDF file at 15–20 pages per minute.

Filing

Paper is a paradox: it is the most intuitive medium to deal with in the short-term, but also the most unwieldy and unmanageable over time. As soon as you layer two sheets into a pile, you have lost the fluidity that is paper’s essential strength. Shuffling through a pile takes an ever increasing amount of time as the pile grows.

For this reason, you want to organize your filing plan in the digital domain as much as possible. Many experts set up elaborate filing plans with color-coded manila folders and will wax lyrical about the benefits of ball-bearing sliding file cabinets. In the real world, few people have the room to store a full-fledged file cabinet.

The simplest form of filing is a chronological file. You don’t even need file folders — I just toss my mail in a letter tray after I scan it. At the end of each month, I dump the accumulated mail into a 6″x9″ clasp envelope (depending on how much mail you receive, you may need bigger envelopes), and label it with the year and month. In all likelihood, you will never access these documents again, so there is no point in arranging them more finely than that. This filing arrangement takes next to no effort and is very compact – you can keep a year’s worth in the same space as a half dozen suspended file folders, as can be seen with 9 months’ worth of mail in the photo below (the CD jewel case is for scale).

There are some sensitive documents you should still file the old-fashioned way for legal reasons, such as birth certificates, diplomas, property titles, tax returns and so on. You should still scan them to have a backup in case of fire.

Date stamping

As you may have to retrieve the paper original for a scanned document, is important to date stamp every page (or at least the first page) of any mail you receive. I use a Dymo Datemark, a Rube Goldberg-esque contraption that has a rubber ribbon with embossed characters running around an ink roller and a small moving hammer that strikes when the right numeral passes by. All you really need is a month resolution so you know which envelope to fetch, thus an ordinary month-year rubber stamp would do as well. Ideally you would have software to insert a digital date stamp directly in the document, but I have not found any yet. A tip: stamp your document diagonally so the time stamp stands out from the horizontal text.

Management

Much as it pains me to admit it, Adobe Acrobat (supplied with the Fujitsu ScanSnap) is the most straightforward way to manage PDF files on Windows, e.g. merge multiple files together, insert new pages, annotate documents and so on. Through web capture OCR, it can create an invisible text layer that makes the PDF searchable with Spotlight. There are alternatives, such as Foxit PDF Page Organizer or PaperPort on Windows, and PDFPen on OS X. Since Leopard, Apple’s Preview app has included most of the PDF editing functionality required, so I take great pains to ensure my Macs are untainted by Acrobat (e.g. unselecting it when installing CS3). See also my article on resetting the creator code for PDF files on OS X so they are opened by Preview for viewing.

Encryption

If you are storing a backup of your personal papers at work or on a public service like Google’s rumored Gdrive, you don’t want third-parties to access your confidential information. Similarly, you don’t want to be exposed to identity theft if you lose a USB Flash stick with the data on it. The solution is simple: encryption.

There are many encryption packages available. Most probably have back doors for the NSA, but your threat model is the ID fraudster rummaging through your trash for backup DVDs or discarded bank statements, not the government. I use OpenSSL’s built-in encryption utility as it is cross-platform and easily scripted (I compiled a Windows executable for myself, and it is small enough to be stored on a Flash card). Mac and UNIX computers have it preinstalled, of course, do man enc for more details.

To encrypt a file using 256-bit AES, you would use the command:

openssl enc -aes-256-cbc -in somefile.pdf -out somefile.pdf.aes

to decrypt it, you would issue the command:

openssl enc -d -aes-256-cbc -in somefile.pdf.aes -out somefile.pdf

OpenSSL will prompt you for the password, but you can also supply it as a command-line argument, e.g. in a script.

Backup

Backing up scanned documents is no different than backing up photos (apart from the encryption requirements), so I will just link to my previous essay on the subject or my current backup scheme. In addition to my external Firewire hard drive rotation scheme, I have a script that does an incremental encryption of modified files using OpenSSL, and then uploads the encrypted files to my office computer using rsync.

Retention period

I tend to agree with Tim Bray in that you shouldn’t bother erasing old files, as the minimal disk space savings are not worth the risk of making a mistake. As for paper documents, you should ask your accountant what retention policy you should adopt, but a default of 2 years should be sufficient (the documents that need more, such as tax returns, are in the “file traditionally” category, in any case).

Fax

The original question was about fax. OS X can be configured to receive faxes on a modem and email them to you as PDF attachments, at which point you can edit them in Acrobat, and fax it back if required, without ever having to kill a tree with printouts. Windows has similar functionality. Of course, fax belongs in the dust-heap of history, along with clay tablets, but habits change surprisingly slowly.

Update (2006-08-26):

I recently upgraded my shredder to a Staples SPL-770M micro-cut shredder. The particles generated by the shredder are incredibly minute, much smaller than those of conventional home or office grade shredders, and it is also very quiet to boot.

Unfortunately, it isn’t able to shred an entire unopened junk mail envelope, and the micro-cut shredding action does not work very well if you feed it folded paper (the particles at the fold tend to cling as if knitted together). This unit is also more expensive than conventional shredders (but significantly cheaper than near mil-spec DIN level 5 shredders that are the nearest equivalent). Staples regularly has specials on them, however. Highly recommended.

Update (2007-04-12):

I recently upgraded my document scanner to a Fujitsu fi-5120C. The ScanSnap has a relatively poor paper feed mechanism, which often jams or double-feeds. Many reviews of the new S500M complain it also sufffers from double-feeding. The 5120C is significantly more expensive but it has a much more reliable paper feed with hitherto high-end features like ultrasonic double-feed detection. You do need to buy ScanTango software to run it on the Mac, however.

Update (2009-01-21):

I moved recently, and realized I have never yet had to open one of those envelopes. From now on, all papers not required for legal reasons (e.g. tax documents) go straight to the shredder after scanning.

Update (2009-09-08):

The new ScanSnap 1500 has ultrasonic double-feed detection. I bought a copy of ABBYY FineReader Express for the Mac. It used to be only available as bundled software with certain scanners like recent ScanSnaps, or software packages like DEVONthink, but you can now buy it as a standalone utility. It is not full-featured, missing some of the more esoteric OCR functionality of the Windows version, batch capabilities and scripting, but works well, unlike the crash-prone ReadIRIS I had but seldom used.

Update (2009-09-22):

Xamance is a really interesting French startup. Their product, the Xambox, integrates a document scanner, document management software and a physical paper filing system. The system can tell you exactly where to find the paper original for a scanned document (“use box 2, third document after tab 7”). In other words, essentially the same filing system I suggest above, but systematically managed in a database for easy retrieval.

It is quite expensive, however, making it more of a solution for businesses. I have moved on and no longer need the safety blanket of keeping the originals, but I can easily see how a complete solution like this would be valuable for businesses that are required for compliance to keep originals, such as notaries, or even government public records offices.

Credit card receipt slips and business cards are problematic for a paperless workflow. They are prone to jam in scanners, have non-standard layouts so hunting for information takes more time than it should, and are usually so trivial you don’t really feel they are worth scanning in the first place. I just subscribed to the Shoeboxed service to manage mine.They take care of the scanning and for pouring the resulting data in a form that can be directly imported into personal finance or contact-management software. I don’t yet have sufficient experience with the service, but on paper at least it seems like a valuable service that will easily save me an hour a week.

Update (2011-01-13):

I finally broke down and upgraded to a ScanSnap S1500M (we have one at work, and it is indeed a major improvement over the older models). In theory this is a downgrade as the fi-5120C is a business scanner, whereas the S1500M is a consumer/SoHo model, but with some simple customization, the integrated software bundle makes for a much more streamlined workflow: put the paper in the hopper, press the button, that’s it. With the fi-5120C, I had to select the scan settings in ScanTango, scan, press the close button, select a filename, drag the file into ABBYY FineReader, select OCR options, click save, click to confirm I do want to overwrite the original file, then dismiss the scan detection window. One step vs. nine.

Update (2012-06-19):

For portable storage of the documents, I don’t bother with manually encrypting the files any more. The IronKey S200 is a far superior option: mil-spec security and hardware encryption, with tamper-resistant circuitry, potted for environment resistance and using SLC flash memory for speed. Sure, it’s expensive, but you get what you pay for (I tried to cut costs by getting the MLC D200, and ended up returning it because it is so slow as to be unusable).

I use Adobe Photoshop CS2 on my Mac as my primary photo editor. Adobe recently announced that the Intel native port of Photoshop would have to wait for the next release CS3, tentatively scheduled for Spring 2007. This ridiculously long delay is a serious sticking point for Photoshop users, specially those who jumped on the MacBook Pro to finally get an Apple laptop with decent performance, as Photoshop under Rosetta emulation will run at G4 speeds or lower on the new machines.

This nonchalance is not a very smart move on Adobe’s part, as it will certainly drive many to explore Apple’s Aperture as an alternative, or be more receptive to newcomers like LightZone. I know Aperture and Photoshop are not fully equivalent, but Aperture does take care of a significant proportion of a digital photographer’s needs, and combined with Apple’s recent $200 price reduction for release 1.1, and their liberal license terms (you can install it on multiple machines as long as you are the only user of those copies, so you only need to buy a single license even if like me you have both a desktop and a laptop).

There is a disaffection for Adobe among artists of late. Their anti-competitive merger with Macromedia is leading to complacency. Adobe’s CEO, Bruce Chizen, is also emphasizing corporate customers for the bloatware that is Acrobat as the focus for Adobe, and the demotion of graphics apps shows. Recent releases of Photoshop have been rather ho-hum, and it is starting to accrete the same kind of cruft as Acrobat (to paraphrase Borges, each release of it makes you regret the previous one). Hopefully Thomas Knoll can staunch this worrisome trend.

Adobe is touting its XMP metadata platform. XMP is derived from the obnoxious RDF format, a solution in search of a problem if there ever was one. RDF files are as far from human-readable as a XML-based format can get, and introduce considerable bloat. If Atom people had not taken the RDF cruft out of their syndication format, I would refuse to use it.

I always scan slides and negatives at maximal bit depth and resolution, back up the raw scans to a 1TB external disk array, then apply tonal corrections and spot dust. One bizarre side-effect of XMP is that if I take a 16-bit TIFF straight from the slide scanner, then apply curves and reduce it to 8 bits, somewhere in the XMP metadata that Photoshop “helpfully” embedded in the TIFF the bit depth is not updated and Bridge incorrectly shows the file as being 16-bit. The only way to find out is to open it (Photoshop will show the correct bit depth in the title bar) or look at the file size.

This bug is incredibly annoying, and the only work-around I have found so far is to run ImageMagick‘s convert utility with the -strip option to remove the offending XMP metadata. I did not pay the princely price for the full version of Photoshop to be required to use open-source software as a stop-gap in my workflow.

Photoshop will embed XMP metadata and other cruft in JPEG files if you use the “Save As…” command. In Photoshop 7, all that extra baggage actually triggered a bug in IE that would break its ability to display images. You have to use the “Save for Web…” command (actually a part of ImageReady) to save files in a usable form. Another example of poor fit-and-finish in Adobe’s software: “Save for Web” will not automatically convert images in AdobeRGB or other color profiles to the Web’s implied sRGB, so if you forget to do that as a previous step, the colors in the resulting image will be off.

“Save for Web” will also strip EXIF tags that are unnecessary baggage for web graphics (and can actually be a privacy threat). While researching the Fotonotes image annotation scheme, I opened one of my “Save for Web” JPEGs under a hex editor, and I was surprised to see literal strings like “Ducky” and “Adobe” (apparently the ImageReady developers have an obsession with rubber duckies). Photoshop is clearly still embedding some useless metadata in these files, even though it is not supposed to. The overhead corresponds to about 1-2%, which in most cases doesn’t require more disk space because files use entire disk blocks, whether they are fully filled or not, but this will lead to increased network bandwidth utilization because packets (which do not have the block size constraints of disks) will have to be bigger than necessary.

I wrote jpegstrip.c, a short C program to strip out Photoshop’s unnecessary tags, and other optional JPEG “markers” from JPEG files, like the optional “restart” markers that allow a JPEG decoder to recover if the data was corrupted — it’s not really a file format’s job to mitigate corruption, more TCP’s or the filesystem’s. The Independent JPEG Group’s jpegtran -copy none actually increased the size of the test file I gave it, so it wasn’t going to cut it. jpegstrip is crude and probably breaks in a number of situations (it is the result of a couple of hours’ hacking and reading the bare minimum of the JPEG specification required to get it working). The user interface is also pretty crude: it takes an input file over standard input, spits out the stripped JPEG over standard output and diagnostics on standard error (configurable at compile time).

ormag ~/Projects/jpegstrip>gcc -O3 -Wall -o jpegstrip jpegstrip.c
ormag ~/Projects/jpegstrip>./jpegstrip < test.jpg > test_strip.jpg
in=2822 bytes, skipped=35 bytes, out=2787 bytes, saved 1.24%
ormag ~/Projects/jpegstrip>jpegtran -copy none test.jpg > test_jpegtran.jpg
ormag ~/Projects/jpegstrip>jpegtran -restart 1 test.jpg > test_restart.jpg
ormag ~/Projects/jpegstrip>gcc -O3 -Wall -DDEBUG=2 -o jpegstrip jpegstrip.c
ormag ~/Projects/jpegstrip>./jpegstrip < test_restart.jpg > test_restrip.jpg
skipped marker 0xffdd (4 bytes)
skipped restart marker 0xffd0 (2 bytes)
skipped restart marker 0xffd1 (2 bytes)
skipped restart marker 0xffd2 (2 bytes)
skipped restart marker 0xffd3 (2 bytes)
skipped restart marker 0xffd4 (2 bytes)
skipped restart marker 0xffd5 (2 bytes)
skipped restart marker 0xffd6 (2 bytes)
skipped restart marker 0xffd7 (2 bytes)
skipped restart marker 0xffd0 (2 bytes)
in=3168 bytes, skipped=24 bytes, out=3144 bytes, saved 0.76%
ormag ~/Projects/jpegstrip>ls -l *.jpg
-rw-r--r--   1 majid  majid  2822 Apr 22 23:17 test.jpg
-rw-r--r--   1 majid  majid  3131 Apr 22 23:26 test_jpegtran.jpg
-rw-r--r--   1 majid  majid  3168 Apr 22 23:26 test_restart.jpg
-rw-r--r--   1 majid  majid  3144 Apr 22 23:27 test_restrip.jpg
-rw-r--r--   1 majid  majid  2787 Apr 22 23:26 test_strip.jpg

Update (2006-04-24):

Reader “Kam” reports jhead offers JPEG stripping with the -purejpg option, and much much more. Jhead offers an option to strip mostly useless preview thumbnails, but it does not strip out restart markers.

I am writing this on a brand-spanking new Apple MacBook Pro (yes, I know, clumsy name). One of the reasons for my purchase is because I have been spending quite a bit of time in trains lately. Trains are one of the most civilized ways to travel, Caltrain certainly beats being stuck behind the wheel in the gridlock that is U.S. Highway 101. A laptop is a good way to get things done during the 3-hour round-trip to Santa Clara.

My last few laptops were company-issued Windows models. I only ever purchased two laptops before, both Macs, a PowerBook 180c in college (it sported a 68K chip, proof that Apple could have kept the PowerBook moniker on an Intel-powered machine) and one of the original white iBooks in 2001 when they first came out around the same time as Mac OS X. For the last ten years or so, I always managed to have ultra-thin and light models (less than 2kg / 4lb) assigned to me, and the MacBook Pro is certainly heavier than I would like. That said, it has a gorgeous screen and a decent keyboard.

Subjectively so far, it does not seem appreciably slower than my dual-2GHz PowerMac G5. I ran Xbench for a more objective comparison, you can see the benchmark results for more info. Unsurprisingly, the disk I/O is in the desktop’s favor, but the Core Do processor holds its own, and even beats the G5 handily on integer performance benchmarks.

I prefer desktops to laptops, for their superior capacity and peripherals. With its relatively puny 80GB of storage capacity, the laptop (it doesn’t really qualify as a notebook given its physical size) is not going to usurp the G5 soon. It doesn’t even have enough capacity to store my complete music library, for instance. I am not looking forward to the usual hassles of synchronizing two computers. Apple’s synchronization solution requires buying a $499 Mac OS X Server license, and third-party solutions are a bit thin.

Now, Apple is a designer PC company, and you want to protect the casework with a decent amount of padding, but the protective case itself must look sharp. I have always had good experience with Waterfield Designs bags made right here in San Francisco, so I naturally got one of their sleevecases. It is made of high-grade neoprene rubber rather than the foam used by other manufacturers, but in exploring my options, I couldn’t help but notice the dizzying array of choices for design-conscious Mac users. For some reason, Australian companies are over-represented, I counted no fewer than 4 manufacturers:

• Crumpler
• STM

  • Foof

  • Bitolithic

  As for the MacBook Pro itself, it is too soon to tell. One thing you immediately notice is how hot it gets, even though the entire aluminum case should act like one big heat sink. I haven’t played with the built-in iSight yet so I can’t compare its quality with that of the stand-alone iSight I have mounted on my desktop.

  The 512MB of RAM installed are woefully inadequate for a supposedly professional machine, but I would rather not pay Apple’s grossly inflated margins on RAM compared to Crucial. I bumped it up to the full 2GB. This upper limit is kind of disappointing when you come from a 64-bit platform (my desktop has 5.5GB of RAM). Laptops benefit even more than desktops from RAM, as free RAM is automatically used as a disk cache, and reduces the need to fetch data from slow and power-hungry 2.5″ hard drives.

  Update (2006-04-05):

  Don’t try to use Monolingual to strip non-Intel architectures to save some space. You will end up rendering Rosetta unusable… I used to disable Classic, I am not sure I would go that far in only allowing Intel binaries to run on my machine.

  Update (2007-08-02):

  More Australian laptop bag manufacturers:

  • Toffee
  • All the Kings’ Men

One of my cousins works for Symbol, the world’s largest bar code reader manufacturer. The fashionable action today is in RFID, but the humble bar code is relatively untapped at the consumer level. The unexpected success of Delicious Library shows people want to manage their collection of books, CDs and DVDs, and as with businesses, scanning bar codes is the fastest and least error-prone way to do so. Delicious Library supports scanning bar codes with an Apple iSight camera, but you have to wonder how reliable that is.

If you want something more reliable, you need a dedicated bar code scanner. They come in a bewildering array of sizes and shapes, from thin wands to pistol-like models or flat ones like those used at your supermarket checkout counter. For some reason, the bar code scanner world seems stuck in the era of serial ports (or worse, PS/2 keyboard wedges), but USB models are available, starting at $70 or so. They emulate a keyboard – when you scan a bar code, they will type in the code (as printed on the label), character by character so as to not overwhelm the application, and follow with a carriage return, which means they can work with almost anything from terminal-based applications to web pages. Ingeniously, most will allow you to program the reader’s settings using a booklet of special bar codes that perform changes like enabling or disabling ISBN decoding, and so on.

The problem with tethered bar code readers is, they are not very convenient if you are trying to catalog items on a bookshelf or read in UPC codes in a supermarket. Symbol has a unit buried deep inside its product catalog, the CS 1504 consumer scanner. This tiny unit (shown below with a canister of 35mm film for size comparison) can be worn on a key chain, although I would worry about damaging the plastic window. Most bar code readers are hulking beasts in comparison. It has a laser bar code scanner: just align the line it projects with the bar code and it will chirp once it has read and memorized the code. The memory capacity is up to 150 bar code scans with timestamps, or 300 without timestamps. The 4 silver button batteries (included) are rated for 5000 scans — AAA would have been preferable, but I guess the unit wouldn’t be so compact, but it is clear this scanner was not intended for heavy-duty commercial inventory tracking purposes.

I bought one to simplify the process of listing books with BookCrossing (even though their site is not optimized for bar code readers), but you have other interesting uses like finding out more about your daily purchases such as nutritional information or whether the company behind them engages in objectionable business practices. I can also imagine sticking preprinted bar-coded asset tracking tags on inventory (e.g. computers in the case of an IT department), and keeping track of them with this gizmo. People who sell a lot of books or used records through Amazon.com can also benefit as Amazon has a bulk listing service to which you can upload a file with barcodes. An interesting related service is the free UPC database.

Mac OS X driver available.

The scanner ships without any software. Symbol mostly sells through integrators to corporations that buy hundreds or thousands of bar code scanners for inventory or point of sale purposes, and they are not really geared to be a direct to consumer business with all the customer support hassles that entails. There are a number of programs available, mostly for Windows, but they don’t seem to have that much by way of functionality to justify their high prices, often as expensive as the scanner itself.

Symbol does make available a SDK to access the scanner, including complete documentation of the protocol used for the device. While you do have to register, they do not make you go through the ridiculous hoops you have to pass to access to the Photoshop plug-in SDK or the Canon RAW decoding SDK. The supplied libraries are Windows-only, however, so I wrote a Python script that works on both Windows and Mac OS X (and probably most UNIX implementations as well, although you will have to use a serial port). The only dependency is the pySerial module.

By default, it will set the clock on the scanner, retrieve the recorded bar codes, correct the timestamps for any drift between the CS 1504’s internal clock and that of the host computer, and if successful clear the unit’s memory and dump the acquired bar codes in CSV format to standard output. The script will also decode ISBN codes (the CS 1504 does not appear to do this by itself in its default configuration). As it is written in Python, it can easily be extended, although it is probably easier to work off the CSV file.

The only configuration you have to do is set the serial port to use at the top of the script (it should do the right thing on a Mac using the Prolific driver, and the Windows driver seems to always use COM8 but I have no way of knowing if this is by design or coincidence). The program is still very rough, specially as concerns error recovery, and I appreciate any feedback.

A sample session follows:

ormag ~>python cs1504.py > barcodes.csv
Using device /dev/cu.usbserial...  connected
serial# 000100000003be95
SW version NBRIKAAE
reading clock for drift
clock drift 0:00:01.309451
resetting scanner clock... done
reading barcodes... done (2 read)
clearing barcodes... done
powering down... done

ormag ~>cat barcodes.csv
UPCA,034571575179,2006-03-27 01:08:48
ISBN,1892391198,2006-03-27 01:08:52

Update (2006-07-21):

At the prompting of some Windows users, I made a slightly modified version, win_cs1504.py, that will copy the barcodes to the clipboard, and also insert the symbology, barcode and timestamp starting on the first free line in the active Excel spreadsheet (creating one if necessary).

Update (2007-01-20):

Just to make it clear: I hereby place this code in the public domain.

Update (2009-11-06):

For Windows users, I have put up videos describing how to install the Prolific USB to serial driver, Python and requisite extensions, and how to use the program itself.

• Installing prerequisites
• Setting up the USB-Serial adapter
• Using the script

Update (2012-07-05):

I moved the script over to GitHub. Please file bug reports and enhancement requests there. Fatherhood and a startup don’t leave me much time to maintain this, so I make no promises, but this should allow people who make fixes to contribute them back (or fork).