Remove black bars (matte) from the video

A channel with only one layout and only one source by default uses the aspect ratio of the video input source when the output is streamed. If the input video signal doesn't match the encoded frame aspect ratio of the channel, bars are added to the sides or top and bottom of the encoded stream when the output is streamed and recorded.

If you see bars on your output but would rather have the image fill the whole screen, you can:

  1. Change the output frame size to match the aspect ratio of the video source at the input, see Match output frame size with aspect ratio of input signal.
  2. Stretch the image to fit the output frame size aspect ratio, see Stretch the image.

The color of the bars (matte) is defined by the Background color that is selected using the custom layout editor for the channel, see Custom layout configuration.

For example:

  • Input signal resolution is 720×480 (a 3:2 aspect ratio)
  • encoded resolution is 640×480 (a 4:3 aspect ratio that is narrower than the input resolution)

Borders are added to the top and bottom of the image to preserve the wider ratio of the input.

For example:

  • Input signal resolution is 720×480 (a 3:2 aspect ratio)
  • encoded resolution is 1280×800 (a 16:10 aspect ratio that is wider than the input resolution)

Borders are added to the left and right of the image to preserve the narrower ratio of the input.

Match output frame size with aspect ratio of input signal

The output frame size is automatically matched only for a layout that has one source. If you have layouts with different frame sizes, switching them while live streaming will cause an interruption and restart of the stream. The same thing happens if you change the resolution of your source while streaming. You can change the output frame size on channels to match the aspect ratio of the video source to avoid this problem.

Change the output frame size of a channel to match the aspect ratio of the video source using the Admin panel

  1. Connect to the Admin panel and login as admin, see Connect to Admin panel.
  1. To determine the input port name of the video source that's used in the channel, select the channel from the Channels menu and click Layouts. The custom layout page opens.
  2. Once you have determined the name of the video input source , select the input port for that video source under Inputs menu.

  1. Make note of the input signal resolution.
  2. From the Channels menu, click Encoding for the channel. The Encoding page opens.

  3. You can either check Use current signal resolution as frame size or you can choose the frame size resolution from the list.

    1. If the source resolution appears in the list, you can choose any resolution that's listed on the same line (i.e. with the same aspect ratio).
    2. If the source resolution doesn't appear in the list, calculate the source resolution and enter it in the Frame size fields.

 

TIP: Temporarily check Use current signal resolution as frame size to see the frame size listed in the Frame size fields, then uncheck that check box and manually enter the value in the Frame size fields.

  1. Click Apply.

Stretch the image

You can remove the matte (black bars) by stretching the image to fit your output frame size using the custom layout editor.

  1. Login to the Admin panel as admin, see Connect to Admin panel.
  1. From the Channels menu, select the channel and click Layouts. The custom layout editor page opens.
  2. In the layouts list, select the row for the layout you want.
  3. In the items list below the layout editing area, select the video source. The video source settings appear.
  4. Uncheck Keep aspect ratio when scaling.

  5. In the layout editing area, click and drag to stretch the video source to fill the frame.
  6. Click Save.