Screen Size and Bitrate

Software name : Avidemux
Software version : 2.4

The screen size and bitrate you use really depends on what you want to do with the video file you are creating. There are some simple things to keep in mind:

The higher the bitrate the larger the actual size of your video. This means that if you use a very high bitrate then it will be slower to download - this may or may not make a difference to you. You may want to try and imagine what kind of internet connection your audience may have. If they have fast connections then the final file size isn't as important. The final choice is yours and it usually means balancing a compromise of quality vs download time.

The actual size (height and width) of the movie will also affect file size. Additionally of course, the height and width affect the playback experience for the viewer. The larger you make the height and width‚ the easier it is to watch, but the bigger the file size. The compromise you strike is also one of judgement.

If, for example, you want the video to be downloaded over an internet connection but you want it to retain a good quality image then perhaps choosing the following might be a good idea :

1. 300 kp/s bittrate
2. 320 (width) x 240 (height) size

If you want a high quality Internet TV file then 640 x 480 and 1000 kp/s (or higher) is more suitable.

The decision is yours as to the most appropriate height and width, bitrate, and resulting file size. Let's assume you have made that decision and look at how to change the bitrate and height/width.

Changing Bitrate

Click on the Configure button on the left of the Avidemux interface.

You will see a pop up window appear

Make sure the 'Encoding mode' is set to Two Pass - Average bitrate from the drop-down menu. Change the setting in the text box ('Dual pass, avg bitrate') to 300. Then click on 'OK'.

Change Screen Size

Now click on Video and choose Filters:

Choose the transform tab on the left, this should be the default view :

Then double click on Resize and a pop up window will appear.

So, let's assume we wish to change the video to 320 (wide) by 240 (high). Enter '320' in the text box next to 'Width' and '240 ' into the text box next to 'Height'. Next choose the correct aspect ratio (the shape of your video file - normally 4:3) from the 'Source' and 'Destination' drop down menus. Then when you are finished press 'OK'

Click 'Close' to return to the main screen.

When you save the file the video will be resized.­