How to Crop Videos Using Avidemux

If you need to crop a video because you only need a small area of it, you can achieve this using the free program Avidemux.

In order to get started, you will need to first open the video file in Avidemux. As cropping the video cannot use the same frame data, you will need to re-encode the video. To do this, use the drop-down box under 'Video Output' to select the format you want the encoded video to be in. You can select anything except 'Copy'. 'Mpeg4 AVC (x264)' is the recommended setting, as it is a very common codec. To crop the video, click on the 'Filters' button below that, and click on 'Crop' under 'Available Filters' on the window that pops up.

After double-clicking on 'Crop', a new window will pop up displaying the video. You can adjust the crop using the four number fields in the top left-hand corner of the window, and you can adjust these values finely using the up and down arrows. You can also click and drag the red rubber band in order to set the crop[ that way, and you can use the 'Hide Rubber Band' checkbox to hide the red lines, so you can see exactly what your crop will look like. The 'Auto Crop' button in the top right-hand corner can also be used if you want to remove black bars from your video, it works best if there is a good contrast between the video and the black bars, so you can use the timeline to scrub through the video to find a good frame. Now just click 'Ok' to set your crop. Now just save the video, and it it will encode a cropped version and export it where you want. You can also combine this with other filters as well as only export a segment of it by 

How to Trim Videos Without Re-encoding Using Avidemux

Sometimes you need to trim a long video clip to get a much smaller section, whether you recorded a much longer video and only need a shorter segment, or need a short clip from an already existing video. The problem with trimming videos using traditional video editors is that they require you to re-encode your video, meaning that it takes a long time, especially on low-end computers, and results in a lowering of video quality. Due to these reasons, it can be useful to know how to trim videos without re-encoding, which essentially just takes the data for he frames you want along with its corresponding audio and copies it into a valid video file. Doing this means that it is super quick, only taking as long as it does to read the file from disk and write your new version.

In order to trim videos in Avidemux, first you need to open the video in Avidemux. This can be done either with using the 'File' menu, or by dragging and dropping the video file onto Avidemux. Then you need to select which part of the video you want. This can be achieved by dragging the selector to the part of the video you want to have as the start of your trimmed video. The use the red-coloured button with an 'A' on it. Then, drag the slider to what you want as the end of your video, and click on the button to the right of that 'A' button, which is labelled 'B'. At this point you have selected the part of your original video to use as your trimmed clip.

To export your clip, simply go 'File' then 'Save As'. This will export your video as an .mkv file, but if you want to change the export format, you can use the drop box directly under 'Output Format' on the left-hand side to change this.

How to Resize Batch Files and Command Prompt

While in Windows 10 you can resize command prompt windows however you want, on Windows 7 your options are much more limited, only allowing you to increase the width of the window to less than half the screen. Even though you can't resize it by dragging, you can still use commands to resize the command prompt window, or if you are making batch files and want to resize the window, you can use this simple command:

mode con cols=<width> lines=<height>

Simply replace the text between the '<' and '>' symbols with the width and height (in character width) you want respectively. You will also need to remove the '<' and '>' symbols, otherwise the code will not work. If you only want to change either the width or height of the window, you can use just the cols or lines part of the code after mode con, to just change that.

How to Change the Colour In Batch Files and Command Prompt

If you have ever made batch files or used command prompt on windows, you have probably noticed that the default command prompt window is white text on a black background. If you have ever wondered if there is a way to change these colours, well yes their is thanks to the 'color' command.

To use it, simply type 'color', followed by the two digit colour code representing your background and foreground (text) colours. These digits are the hexadecimal values representing the 16 available colours to choose from, as listed below. A valid example would be to type 'color 25', to set the background to green and the text to purple.

Colour	Code	Colour	Code
Black	0	Grey	8
Blue	1	Light Blue	9
Green	2	Light Green	A
Aqua	3	Light Aqua	B
Red	4	Light Red	C
Purple	5	Light Purple	D
Yellow	6	Light Yellow	E
White	7	Bright White	F

You can get this list in command prompt by using the 'color' command followed by an invalid colour code. Something to note is that if you just want to change the text colour, you an simply use the one digit colour code for that colour, such as using 'color 2' to set the text colour to green.