Settings that You Specify When You Create an Elastic Transcoder Preset

The preset that you want to use as a starting point for your new preset. Elastic Transcoder copies the values from the preset that you select into the fields for the new preset. You can choose either one of the default Elastic Transcoder presets or a preset that you created.

The name of the preset. We recommend that the name be unique within the AWS account, but uniqueness is not enforced. The maximum length is 40 characters.

A description of the preset. The maximum length is 255 characters.

The container type for the output file.

The video codec for the output file.

The profile that you want to use for the output file. When the video codec is H.264, Elastic Transcoder supports the following profiles:

For more information about H.264 profiles, see Profiles in the Wikipedia entry "H.264/MPEG-4 AVC."

When the video codec is VP8, Elastic Transcoder supports values of 0, 1, 2, and 3.

The H.264 level that you want to use for the output file. Select the applicable value.

For more information about levels, see Levels in the Wikipedia entry "H.264/MPEG-4 AVC."

The maximum number of previously decoded frames to use as a reference for decoding future frames. If you enter a value greater than the recommended value based on the values that you specified for Max Height, Max Height, and Level, Elastic Transcoder displays a message that contains the recommended value. For a detailed explanation, including the calculation that Elastic Transcoder performs, see MaxReferenceFrames in the topic Create Preset.

The maximum number of frames between key frames. Key frames are fully encoded frames; the frames between key frames are encoded based, in part, on the content of the key frames. The value is an integer formatted as a string; valid values are between 1 and 100000, inclusive. A higher value results in higher compression but may also discernibly decrease video quality.

For more information about key frames, see the Wikipedia entry Video compression picture types.

Whether to use a fixed value for Fixed Number of Frames Between Keyframes:

The bit rate of the video stream in the output file, in kilobits/second. If you specify auto, Elastic Transcoder uses variable bitrate encoding to optimize the bitrate and to maintain a consistent quality for each frame of the output.

Valid values for the video bit rate depend on the value that you chose for Codec:

The frames per second for the video stream in the output file. Select the applicable value.

If you specify auto, Elastic Transcoder uses the detected frame rate of the input source. If you specify a frame rate, we recommend that you perform the following calculation:

Frame rate = maximum recommended decoding speed in luma samples/second / (<xref linkend="preset-settings-video-max-width" xrefstyle="select: nopage"/> * <xref linkend="preset-settings-video-max-height" xrefstyle="select: nopage"/>)

where maximum recommended decoding speed in luma samples/second is less than or equal to the maximum value listed in the following table, based on the value that you specified for Level.

The maximum width of the output video in pixels. If you specify auto, Elastic Transcoder uses 1920 (Full HD) as the default value. If you specify a numeric value, enter an even integer between 128 and 4096.

For more information, see Max Height.

The maximum height of the output video in pixels. If you specify auto, Elastic Transcoder uses 1080 (Full HD) as the default value. If you specify a numeric value, enter an even integer between 96 and 3072.

If you specified H.264 for Codec We recommend that you specify values for Max Width and Max Height so the product of the two values is less than or equal to the applicable value in the following table.

Specify one of the following values to control scaling of the output video:

The following table shows possible effects of Sizing Policy settings on the output video:

When you set PaddingPolicy to Pad, Elastic Transcoder may add black bars to the top and bottom and/or left and right sides of the output video to make the total size of the output video match the values that you specified for Max Width and Max Height. For more information, see the table at Sizing Policy.

The value that Elastic Transcoder adds to the metadata in the output file. If you set Display Aspect Ratio to auto, Elastic Transcoder chooses an aspect ratio that ensures square pixels. If you specify another option, Elastic Transcoder sets that value in the output file.

The audio codec for the output file. This value must be AAC.

The sample rate of the audio stream in the output file, in Hz. If you want Elastic Transcoder to automatically detect the sample rate of the input file and use that value for the output file, select auto. If you want to specify the sample rate, select the applicable value.

The bit rate of the audio stream in the output file, in kilobits/second. Enter an integer between 64 and 320, inclusive.

The number of audio channels in the output file. If you want Elastic Transcoder to automatically detect the number of audio channels in the input file and use that value for the output file, select auto. If you want to specify the number of audio channels in the output file, select the applicable value.

The format of thumbnails, if any. Valid formats are jpg and png.

You specify whether you want Elastic Transcoder to create thumbnails when you create a job. For more information, see Thumbnail Filename Pattern in the topic Settings that You Specify When You Create an Elastic Transcoder Job.

The number of seconds between thumbnails. Specify an integer value.

The maximum width of thumbnails in pixels. If you specify auto, Elastic Transcoder uses 1920 (Full HD) as the default value. If you specify a numeric value, enter an even integer between 32 and 4096.

The maximum height of thumbnails in pixels. If you specify auto, Elastic Transcoder uses 1080 (Full HD) as the default value. If you specify a numeric value, enter an even integer between 32 and 3072.

Specify one of the following values to control scaling of thumbnails:

The following table shows possible effects of Sizing Policy settings on thumbnails:

When you set PaddingPolicy to Pad, Elastic Transcoder may add black bars to the top and bottom and/or left and right sides of thumbnails to make the total size of the thumbnails match the values that you specified for thumbnail Max Width and Max Height settings. For more information, see the table at Sizing Policy.