Mpeg4CRT 1.0

Brain Arts Software Solutions

Mpeg4 Crop/Resize Tool 1.0

This program is freeware. You may freely distribute it as is. Use it at your own risk.

What is Mpeg4CRT?

In most cases DVD and DVB videos are encoded with black bars in the picture. For making a high quality Mpeg4 video from such a source you have to get rid of those bars. If you ever had problems finding out what crop and resize settings to use for this, Mpeg4CRT is the tool for you. You only have to mark the actual movie in a DVD screenshot and Mpeg4CRT calculates the settings needed.

For further information on using Mpeg4CRT and encoding Mpeg4 videos visit www.brain-arts.de (German site).

The Crop / Resize Calculator

First you have to capture one or more bitmaps of the DVD or DVB video. Take some pictures where the corners are bright, so you can easily distinguish between the black bars and the actual movie.

This is the point where Mpeg4CRT comes in. Open a bitmap with "Open BMP ..." and select the correct DVD aspect ratio. If you're not sure about this, look what your DVD ripper or player displays. You can change which target resolution the resulting video should have, too.

Now mark the corners of the actual movie with a click in the shown bitmap. You have to mark at least two opposite corners to get a result. Mpeg4CRT displays the area you marked with a dotted line. The area that will be visible using the current settings is visible inside the solid line.

Width and height of the target video (both multiples of 16) and the crop values to get the correct aspect ratio are shown on the right hand side. To give you additional information about your Mpeg4 video, the target aspect ratio and pixel count are shown as well.

The pixel count may differ from the value specified above. You should experiment a little with the target pixel count to get the expected result. Another way of altering the output values is to change the visible part of the DVD movie.

The values calculated by Mpeg4CRT remain until you click on the "Reset" button or open a bitmap with different width or height, so you can use more than one screenshot of a movie to find the best settings.

You can get a first glimpse of how your video would look like by clicking the "Preview" button. The preview shows you what image size and what aspect ratio the target video will have using the current settings. It doesn't give you an idea about the quality of the target video.

If you are satisfied with the settings you can save the calculated values into a text file by clicking the "Save Values ..." button or simply copy them to the clipboard to use them for making your Mpeg4 video.
for further usage.

The Bitrate Calculator

The bitrate calculator of Mpeg4CRT has two modes of operation. You can either calculate the needed bitrate to fill your CDs (default) or calculate how much diskspace your video will need using a given bitrate.

In both modes you have to define the runtime of your video, also the number and bitrate of the audio streams. These values will affect the calculated results.

If you want to calculate the target bitrate for the video stream, you have to type in a value for the diskspace the video may fill. You can either choose a CD size and the number of CDs to use or specify a custom value. The calculated bitrate is shown at the bottom.

If you want to know how big the video will be using a given bitrate, you have to specify this bitrate. Mpeg4CRT will display the size of your target video in megabytes and a suggestion how many CDs of what size should be used, too.