Video scaling behavior and aspect ratios - MediaConvert

Video scaling behavior and aspect ratios

You can choose how AWS Elemental MediaConvert scales your input video image to the output resolution that you specify by using Scaling behavior.

The following tables show how Scaling behavior, Scaling padding, Height, and Width interact to change the output image.

Default (Fit with padding)

If you choose Default (Fit with padding) for your Scaling behavior, MediaConvert scales your video image to your output resolution. Then, if your input resolution has a different aspect ratio than your output resolution, MediaConvert pads your video image until it matches the dimensions of your output resolution.

For example, if your input file is 1280 pixels by 720 pixels and you specify an output resolution that is 640 pixels by 480 pixels, MediaConvert reduces the image size to 640x360 and then pads the top and bottom of the image so that the final video resolution is 640x480. MediaConvert does not use cropping for the Default scaling behavior.

Key

The following key graphic shows input and output image width, height, cropping, and padding. In this key graphic, input dimensions (on the top and left) are in blue and output dimensions (on the right and bottom) are in red.


                Aspect Ratio Key

The following table shows example image scaling behavior when your input and output resolutions differ. For details about to read the images, reference the previous key graphic.

Condition

Input

Output

Input width less than output width

Input height less than output height

Input width less than output width

Input height greater than output height

Input width greater than output width

Input height less than output height

Input width greater than output width

Input height greater than output height

Stretch to output

If you choose Stretch to output for your Scaling behavior, MediaConvert stretches or shrinks your video image to your output resolution.

For example, if your input image is 200 pixels by 200 pixels and you want an output resolution that is 300 pixels by 400 pixels, MediaConvert increases the size of your input image to 300 pixels by 400 pixels, distorting the proportions of your output image. MediaConvert does not use padding or cropping for the Stretch to output scaling behavior.

Important

If your input resolution has a different aspect ratio than your output resolution, your output image will be distorted when compared to your input image.

Key

The following key graphic shows input and output image width, height, cropping, and padding. In this key graphic, input dimensions (on the top and left) are in blue and output dimensions (on the right and bottom) are in red.


                Aspect Ratio Key

The following table shows example image scaling behavior when your input and output resolutions differ. For details about to read the images, reference the previous key graphic.

Condition

Input

Output

Input width less than output width

Input height less than output height

Input width less than output width

Input height greater than output height

Input width greater than output width

Input height less than output height

Input width greater than output width

Input height greater than output height

Fit

If you choose Fit for your Scaling behavior, MediaConvert scales your input image until it fits inside the dimensions of your output resolution, without exceeding the dimensions of your output resolution.

For example, if your input file is 200 pixels by 200 pixels and you want an output resolution that is 300 pixels by 400 pixels, MediaConvert increases the image to 300 pixels by 300 pixels. MediaConvert does not add padding to your output when you choose Fit.

Key

The following key graphic shows input and output image width, height, cropping, and padding. In this key graphic, input dimensions (on the top and left) are in blue and output dimensions (on the right and bottom) are in red.


                Aspect Ratio Key

The following table shows example image scaling behavior when your input and output resolutions differ. For details about to read the images, reference the previous key graphic.

Condition

Input

Output

Input width less than output width

Input height less than output height

Input width less than output width

Input height greater than output height

Input width greater than output width

Input height less than output height

Input width greater than output width

Input height greater than output height

Fit without upscaling

If you choose Fit without upscaling for your Scaling behavior, MediaConvert decreases the size of your input image until it fits inside the dimensions of your output resolution, without going over any of the dimensions of your output resolution. If your input image is smaller than your output image, MediaConvert does not increase the size of your image.

For example, if your input image is 400 pixels by 400 pixels and you want an output resolution that is 200 pixels by 300 pixels, MediaConvert shrinks your input image to 200 pixels by 200 pixels. MediaConvert does not add padding when you choose Fit without upscaling.

Note

You cannot choose Fit without upscaling when you enable Automated ABR in Apple HLS, DASH, or CMAF output groups.

Key

The following key graphic shows input and output image width, height, cropping, and padding. In this key graphic, input dimensions (on the top and left) are in blue and output dimensions (on the right and bottom) are in red.


                Aspect Ratio Key

The following table shows example image scaling behavior when your input and output resolutions differ. For details about to read the images, reference the previous key graphic.

Condition

Input

Output

Input width less than output width

Input height less than output height

Input width less than output width

Input height greater than output height

Input width greater than output width

Input height less than output height

Input width greater than output width

Input height greater than output height

Fill

If you choose Fill for your Scaling behavior, MediaConvert scales your input image until it fills the dimensions of your output resolution, and crops anything that exceeds the dimensions of your output resolution.

For example, if your input file is 200 pixels by 200 pixels and you want an output resolution that is 300 pixels by 400 pixels, MediaConvert increases the size of your input image to 400 pixels by 400 pixels, crops off the top and bottom 50 pixels, and returns a 300 pixel by 400 pixel file. MediaConvert does not add padding to your output when you choose Fill.

Key

The following key graphic shows input and output image width, height, cropping, and padding. In this key graphic, input dimensions (on the top and left) are in blue and output dimensions (on the right and bottom) are in red.


                Aspect Ratio Key

The following table shows example image scaling behavior when your input and output resolutions differ. For details about to read the images, reference the previous key graphic.

Condition

Input

Output

Input width less than output width

Input height less than output height

Input width less than output width

Input height greater than output height

Input width greater than output width

Input height less than output height

Input width greater than output width

Input height greater than output height