Dragging markers to change image size is the essential feature in all picture editor apps. Lots of programmers know how to implement the drag and change size feature. But very little people know the mechanism behind the simple formula. In this tutorial, we will talk about how to calculate the final width and height of the image after dragging the right bottom markers.
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How to Backup and Mirror a Subversion Repository
Subversion has been used as my project version control system for years. Backup and restore subversion data will be a critical issue. Here are three ways to create a full mirror of a Subvrsion repository:
- File Copy: treat the repository like any other filesystem and recursively copy it to the mirror location.
- Dump/Load: Use svnadmin dump and svnadmin load.
- Hotcopy: Use svnadmin hotcopy.
Change GIF File Color
GIF format was introduced in 1987. It is widely used on Websites because it is the simplest way to implement the animations with a very small size. It is supported by all the browsers. Compare with the flash, it doesn’t need any plugin to play the animation in the web browser and it is very small in size.
GIF has two format, GIF87a and GIF89a. GIF87a is the original version of GIF format and GIF89a is the enhanced version, which supports for animation delays, transparent background and storage of application-specific metadata. By looking at the first six bytes of the GIF file, we can recognize the two versions by ASCII code, “GIF87a” and “GIF89a” respectively.
Playing GIF format is a very interesting job. Today I will show you how to change color of a GIF file. To replace the color of GIF files, we need to find out the color code first. Here is GIF animation which I am downloading from the internet. I downloaded it several months ago, so I forgot the original location.
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How to Backup Your DVR Record
Many people subscribe the DVR services, such as DirecTV, TiVo and Dash Network, etc. All these TV service providers have their own DVR receivers with different models. And they are not compatible with each other. That means you can not use TiVo DVR to receive the signals from DirecTV. Sometimes, it is worse than that. After you cancel the services, you even can not watch the TV shows in the DVR. So it is quite important to backup your DVR records in DVD or in your computers as mp4 or AVI videos.
To achieve this job, you need an S-Video cable, a DVD recorder or a computer with capture card. If you prefer to back up your DVR records to the DVD disk directly, you will not need a computer. You just connect the DVR output with the DVD recorder input with the S-Video, and press the play button to start the analogue backup. And if you choose to backup DVR to Computer, you need to connect DVR to computer’s capture card and the left processes are the same.
There is only one problem I need to mention. This way is a real time recording, which means it will take your one hour if your TV show is one hour. But it will be a very tough job if you have 100 hours TV shows need to be backup.
Wireless TV Internet Connection Kit
Today, we can access the internet everywhere, and without any cable pain. With the big wireless technology development, we can get faster speed, bigger bandwidth without cable connections. The biggest change in our life is that we don’t need to connect many cables in our home theater any more. We can build our wireless home theater with a very low cost by Wireless TV Internet Connection Kit.
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