HTML5 has a lot of new features. One of the coolest but not often utilized is the new <video> element. It allows pages to embed video files without requiring the user to download a plugin. By default YouTube videos use HTML5 if the user's browser supports it, and use Flash otherwise. Read More...

Google Fusion tables is a database system integrated with Google Maps and Google Chart Tools. It's designed to allow visualization, collaboration, and sharing of data, emphasizing central storage to prevent versioning problems, robust sharing, collaboration, and permissions tools to control who can see what, and who can change what. Read More...

We've covered almost everything we need to create QR Codes. The next thing we need is version information blocks. The version information blocks simply tell the reader what version the symbol is, and therefore how many modules wide and tall it is. Table 11 shows the top-right version of each version information block. Review Part 2 to see the positioning; in particular, remember to mirror these along the NW-SE axis to place them in the lower-left position. Read More...

Now that we've got the data and error correction sorted out, we're almost ready to place it in the symbol. As seen in Part 2, the data and error correction modules basically go everywhere that isn't taken up by something else. The reason we're not quite ready to place it is that we haven't established the locations of the alignment patterns. Read More...

I had planned on holding off the error correction until later, but it really fits better right here. Before error correction is done, the data that we've generated must be broken down into "code words", which are just 8-bit bytes. All we have to do is take our "bit stream" from the last tutorial, and break it into 8-bit sections. Each one is represented by a number in the range 0 to 255. Read More...

Now we'll cover how the data is encoded. There are several steps involved. First, the encoding method is chosen, then the raw data is converted to binary based on the encoding method, then the error correction algorithm is applied, and then the data is placed in the symbol. Finally a mask is selected and applied. For now I'll cover the encoding methods, and conversion to binary, and save the rest for later. Read More...

The next important thing we'll look at is the structure of a QR code. The below diagram shows names of the different sections of a QR symbol. Then I'll go over each one in more detail. Keep in mind that below if I mention one copy of something being the original and another a duplicate, it's just for the convenience of thinking about it that way - since the data is the same, it makes no difference which is placed first. Below I indicate what information is stored in the different sections, but I don't get into detail on how that information is encoded. I'll explain that in later weeks, and add in links as I complete the different sections. Read More...

Recently I undertook a task to develop a QR Code generator. I was surprised to find how difficult it was to find complete information on the QR Code specification. Most of what I found only explained part of the puzzle. So my new endeavor is to completely explain the spec. I want a skilled developer to be able to create a QR Code generator just by reading these tutorials. So I'll spend the next few weeks covering everything there is to know about QR Code generation. Read More...

While it may not have the reach of Apple's iOS when considering other classes of devices, Android is the most popular smartphone platform in the United States. So if you're creating a smart phone app, Android is the way to go (or of course you can publish for multiple platforms). Further, if you ask me, which you sort of did by reading this post, Android is the most well-designed platform from a developer's perspective. Now that I've convinced you to develop for Android, here are a few steps to get you there. Read More...