H.264 for Blu-ray setting in Compressor
The built-in H.264 for Blu-ray setting in Compressor (in the Create Blu-ray destination) uses the H.264 for Blu-ray transcoding format. This format encodes H.264 elementary stream files for Blu-ray and AVCHD DVD authoring.
Note: You can also create custom settings that use the H.264 for Blu-ray transcoding format. However, the built-in H.264 for Blu-ray setting (in the Settings pane) analyzes your source media and assigns optimal properties to ensure the best possible transcoding results.
The properties of built-in and custom settings that use this transcoding format are located in the General inspector and Video inspector (described below).
Note: The built-in H.264 for Blu-ray setting encodes only a video file. To encode the accompanying audio, use the Dolby Digital audio setting. The easiest way to do this is to apply the Create Blu-ray destination to your source file, which adds the appropriate video and audio settings to your job.
Displays the setting name and transcoding format, as well as an estimated output file size. When you add a setting to a job or change the setting’s properties, this summary is automatically updated.
Name: Displays the name of the setting.
Description: Displays the description of the setting.
Extension: Displays the extension of the output file (.264).
Allow job segmenting: This checkbox is dimmed because job segmenting is not available for this setting.
Default location: Choose an item from the pop-up menu to set the default save location for transcoded files.
Stream Usage: Use the pop-up menu to set whether the output file is transcoded for Blu-ray Disc or AVCHD.
This area contains one property:
Set duration to: Sets the processing algorithm used to adjust the frame rate during transcoding. Select one of the following options:
[Percentage] of source: Modifies the output clip’s speed by a percentage of the source clip’s speed. Enter a value in the percentage field or choose a preset value from the adjacent pop-up menu (with a down arrow).
[Total duration]: Sets the duration of the clip. Enter a timecode duration in the field or click the arrows to increase or decrease the time.
So source frames play at [frame rate] fps: Nondestructively changes the playback speed of the clip, without discarding frames or creating new frames. This setting has no effect unless the “Frame rate” value in the Video inspector is different from the source file’s frame rate. For example, if you add a 10-second source file with a frame rate of 24 fps to Compressor, set the “Frame rate” property in the Video inspector to 25 fps, then select “So source frames play at 25 fps” in the General inspector, the duration of the transcoded clip (at 25 fps) is 9 seconds and 15 frames.
For more information, see Retime video and audio using Compressor.
Pixel aspect ratio: For settings that use the H.264 format, the pixel aspect ratio is automatically set to Square.
Frame rate: Use this pop-up menu to set the playback rate (the number of images displayed per second) of the output file. See Retiming options in Compressor.
Field order: For settings that use the H.264 format, the field order is automatically set to Progressive (complete frames are scanned).
Color space: Use this pop-up menu to convert the source media to a new color space. The default setting is Automatic, which allows Compressor to choose the best color space based on the selected preset. You can also choose a manual setting to override the default.
Automatically select bit-rate: Select this checkbox to have Compressor automatically compute the best bit rate for the output file, based on the duration of the source file. If the checkbox is not selected, you can set the average and maximum bit rates by dragging the “Average bit rate” and “Maximum bit rate” sliders or entering values in the text fields.
Multi-pass: Select this checkbox to turn on multi-pass encoding that uses additional analysis of video frames to produce a high-quality output file. For faster (single-pass) transcoding, turn this feature off by deselecting the checkbox.
Cropping and padding
Customize the final cropping, sizing, and aspect ratio using the Cropping & Padding properties. Cropping removes video content from an image. Padding scales the image to a smaller size while retaining the output image’s frame size. For more information about these properties, see Intro to modifying frame size in Compressor.
Cropping: This pop-up menu sets the dimension of the output image. The custom option allows you to enter your own image dimensions in the fields; other options use predetermined sizes. The Letterbox Area of Source option detects image edges and automatically enters crop values to match them. This is useful if you want to crop out the letterbox area (the black bars above and below a widescreen image) of a source media file.
Padding: This pop-up menu sets the scaling of the output image while retaining the output image’s frame size. The custom option allows you to enter your own scaling dimensions in the fields; other options use predetermined dimensions.
The following properties set the processing algorithm used by Compressor during the transcoding process. For more information about using these controls, see Retime video and audio using Compressor and Modify timing and frame rate in Compressor.
Resize filter: This pop-up menu sets the resizing method. There are several options:
Nearest Pixel (Fastest): Samples the nearest neighboring pixel when resizing an image. This option provides the fastest processing time, but it is more likely to show aliasing artifacts and jagged edges.
Linear: Adjacent pixel values are averaged using a linear distribution of weights. Produces fewer aliasing artifacts than Nearest Pixel, with a small increase in processing time.
Gaussian: Adjacent pixel values are averaged using a gaussian distribution of weights. This provides a medium trade-off between processing time and output quality.
Lanczos 2: Adjacent pixel values are averaged using a truncated sinc function. This option is slower than Gaussian but provides sharper results.
Lanczos 3: Similar to Lanczos 2 but averages more pixel values. This option is slower than Lanczos 2 but may produce better results.
Bicubic: Adjacent pixel values are averaged using a bicubic function. The processing time and output are most similar to Lanczos 2 and Lanczos 3.
Anti-aliased (Best): Provides the highest output quality, but can take substantially longer to process.
Retiming Quality: This pop-up menu sets the retiming method. There are four options:
Fast (Nearest Frame): Linearly interpolates frames using nearest neighbor frames.
Good (Frame Blending): Blends neighboring frames using a filter to produce good-quality interpolation.
Best (Motion Compensated): Uses optical flow to interpolate using areas of movement between neighboring frames to produce high-quality output.
Reverse Telecine: Removes the extra fields added during the telecine process to convert the film’s 24 fps to NTSC’s 29.97 fps. Choosing this item disables all the other Quality controls. See Use reverse telecine in Compressor.
Adaptive details: Select this checkbox to use advanced image analysis to distinguish between noise and edge areas during output.
Anti-aliasing level: Sets the softness level in the output image. Double-click the value and then manually enter a new value or drag the slider to the right to increase softness. This property improves the quality of conversions when you’re scaling media up. For example, when transcoding SD video to HD, anti-aliasing smooths jagged edges that might appear in the image.
Details level: Sets the amount of detail in the output image. Double-click the value and then manually enter a new value or drag the slider to set the value. This sharpening control lets you add detail back to an image being enlarged. Unlike other sharpening operations, the “Details level” property distinguishes between noise and feature details, and generally doesn’t increase unwanted grain. Increasing this value may introduce jagged edges, however, which can be eliminated by increasing the “Anti-aliasing level” slider.
Dithering: When selected, adds a certain type of noise to images to prevent large-scale distracting patterns such as color banding. If your image has excessive noise after rendering, deselect this checkbox.
For a list of available video effects in Compressor, and instructions on how to add a video effect to a setting, see Add and remove effects in Compressor.